A Changing Perception of Taste Perception

Previous Ingredients sections have discussed individual basic tastes—sweet, salty, sour, bitter, and umami. But when you try to write about all of them in one article, your view of them—or to put it more precisely, your perception of taste perception—changes rather dramatically.

For starters, when I first conceived of this article several months ago, I visualized four quadrants, one for each basic taste, and off to the side, like a satellite, one for umami. Since then, I realized that my view was probably as antiquated as those of individuals who once saw the earth to be flat. In truth, these basic tastes, when applied to a formulation, are very interrelated—having complex relationships with each other, creating enhancements, masking effects, synergies, and exciting flavor combinations.

A chef would probably call the final product food and the process cooking and leave the discussion at that. But I can’t help wondering, especially when considering the numerous ingredient and research developments that are occurring in the area of taste perception, whether the food formulator has taken full advantage of these developments and the benefits they offer. After all, recognizing that the earth is not flat is only the first step—although it is a big step because it requires a changing perception.

Also, when I first conceived of this article, I thought I would be writing solely about ingredients that impart a specific basic taste—you know, sweeteners, salt, acidulants, etc. I quickly realized how wrong I was. A number of ingredients do not necessarily provide the basic taste, but still impact the taste perception. These include colors, gums, aroma compounds, flavor enhancers, and so on.

Furthermore, I realized that the other senses, especially smell, can play an important role in the perception of taste. The Nobel Prize in Physiology or Medicine for 2004 was awarded to two researchers for their work with odorant receptors and the organization of the olfactory system. Their discoveries are helping to clarify how the sense of smell works. Of particular relevance to this article, an understanding of these findings could have an impact on food development, especially in the area of taste perception. Later in this article I’ll be discussing this development in more detail.

This article will also be looking at other cutting-edge research developments involving genetics, including how flavor preferences can contribute to obesity or, if that knowledge is used correctly, how flavor preferences may also help address that problem. Work is also being done with “supertasters”—those individuals born with a genetic trait that makes them very sensitive to tastes.

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And finally, it was easy to see that these new developments related to taste perception can be applied to the development of a number of new or existing products that can help address health problems such as obesity and diabetes, as well as help introduce mainstream consumers to exciting products from a variety of cultures, ranging from Hispanic to Asian. In addition to creating these new opportunities, hopefully these developments—some of which were the result of decades of research—will help food formulators rediscover their benefits, as well as reacquaint them with approaches taken by other cultures.

Because the ingredients territory related to the basic tastes is so broad, I have tried to organize the following developments around the specific roles they play in taste perception. Some of these developments will involve salt, sweeteners, umami-active substances, acidulants, colors, gums, flavors, flavor enhancers, and many others, including the findings of various research projects in genetics and different approaches that product developers and ingredient suppliers are taking, ranging from more traditional methods such as encapsulation to biotechnological and molecular approaches.

The article will end with a few thoughts on different taste combinations and how they When how they impact taste perception.

With that, here are a wide range of developments that I hope something of which will appeal to everyone’s tastes:

Salt and Taste Perception. When writing about the basic taste salty, the first ingredient that comes to mind is, of course, salt. What I find interesting here, especially in relation to this article, is the number of ways that salt can enhance the perception of the basic tastes, and, as a result, play an important role in food products being developed today. These food products might include lower-sodium foods, calcium-fortified products, Hispanic and other spicier foods, foods having contrasting tastes such as sweet and salty, foods that use flavor enhancers and masking agents, snack coatings, and many other examples, where the important role of salt, and specifically its ability to affect taste perception, may be overlooked.

Here are just a few examples that a food formulator might want to consider when developing some of the above products:

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From both the outside and inside of a food product, salt can have an impact on taste perception. When used as a topping, salt can enhance the perception of saltiness. By adhering to the surface of the product—e.g., a potato chip—salt can provide a clean quick taste, as it dissolves instantly on the tongue. Furthermore, as a topping, a smaller amount of salt would be needed to accomplish that function. Sodium’s mobility or immobility in a food system—how it binds or doesn’t bind—can also affect whether it is perceived to be more salty or less salty in a system. Furthermore, calcium, which offers nutritional benefits, especially in a fortified product, can also interact with sodium and affect perception of taste. 

As has been discussed in previous Ingredients sections, the level of salt can suppress bitterness so that more sweetness can come through in a finished product. In some applications, salt can enhance sweetness, while in other applications, it can help mask or reduce the sweetness levels. Because of salt’s special abilities, it can play an important role in helping to modulate the flavors of future food products.

A product that I mentioned in the past, Morton’s® Hot Salt, may also signal future developments. As you may recall, this product consists of salt, red peppers, and the smoky hot flavor of chipotle. While this product is a good illustration of combining heat and saltiness, one can’t help but wonder, “Why stop there?” Is it possible to create other products such as “sweet salt” or “cool salt” or “sour salt”?

When considering the plausibility of the previous point, keep in mind that a new line of products which combine nutritional components into a seasoning format has been introduced by Double K, LLC, P.O. Box 6573, Springfield, VA 22150 (phone 703-455-6595; fax 703-455-6596; www.grainy.net). One of the products, of special interest here, is Grainy® Nutritional Salt made with the added nutrients of grains and beans which offer potential health benefits. According to the ingredient label, this product consists of oat bran, barley, wheat bran, whole millet, whole wheat, rice, pinto beans, garbanzo beans, lentils, adzuki beans, black beans, and sea salt. Other Grainy® seasonings (including Nutritional Pepper) are made by a patented process which blends assorted grains, beans, garden vegetables, soy products, protein products, fresh fruits, and various herbs. 

The properties that different salt forms can offer may have an impact on taste perception as well. For example, at the 2004 IFT Annual Meeting + Food Expo®, a dendritic salt called Star Flake® was highlighted by Morton Salt, 123 N. Wacker Dr., Chicago, IL 60606 (phone 312-807-2000; fax 312-807-2899; www.mortonsalt.com). The high-purity, food-grade sodium chloride is produced in vacuum pans from chemically purified brine to which a crystal-modifying agent is added. The resultant crystals are porous, star-shaped modified cubes with special physical properties, including high specific surface area, rapid dissolution rate and flowability, high liquid adsorptive capacity and caking resistance, and low apparent density.

The salt is said to combine the most useful features of vacuum-granulated salt and grainer flake salt. Unlike the cubical crystals of vacuum salt or the flat, irregular crystal aggregates of grainer salt, dendritic crystals are branched or star-like in shape. Like vacuum salt, dendrites are concentric, yet they exhibit the low-density, high-specific surface area, and rapid dissolution properties of fine grainer flake salt. A special feature is the cavitation or macro-porosity of the crystal.

Of special interest here is how some of these properties can influence taste perception. For instance, dendritic salt exhibits excellence adherence properties, while other forms of salt might roll or bounce off certain surfaces, with much less retention. Also, dendritic salt exhibits a rapid dissolution rate.

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Cargill Salt, P.O.Box 5621, Minneapolis, MN 55440 (phone 888-385-7258; fax 952-984-8715; www.cargillsalt.com) notes that the size and shape of the individual crystals of its salt products can give salt its special properties, which would include those that would affect taste perception. For example, its Alberger® brand has high-purity crystals with a hollowed-out pyramidal structure. This distinctive crystal helps provide excellent blendability, rapid solubility, high absorption, and low bulk density. The company also creates custom solutions with salt that would meet particular taste and texture specifications.

There have also been ingredient blends recently introduced that can have an impact in the area of salt and taste perception.

For example, a potassium chloride taste modifier called NeutralFres® has been developed by Prime Favorites, Inc., 31 Grove Ave., Morris Plains, NJ 07950 (phone 973-455-0600; fax 973-455-601). The natural ingredient formulation, when blended with potassium chloride at about 2%, is said to remove the metallic, bitter taste of potassium chloride. The blended potassium chloride product is designed to reduce or eliminate sodium chloride in packaged foods such as soups, gravies, sauces, marinades, or other convenience items requiring reconstitution. It may also be used in canned or bottled prepared foods.

A range of salt reducers has been introduced by the Carbery Group, Ballineen, Country Cork, Ireland (phone 353-23-47222; www.carbery.com). According to the company, the salt reducers are said to deliver a rich savory taste and help reduce salt usage significantly. Application solutions have been developed for sauces, snacks, and ready meals.

Before we move on to the next section, I think a point needs to be emphasized here. Although some of the studies involving salt’s functionality were conducted more than 10 years ago, the results that they found are not only extremely timely (remember the wide range of products mentioned in the first paragraph of this section on salt), but also can be easily overlooked. Some of these studies—for example, those on salt and binding—can provide particularly useful methods (or “tricks” if you wish to use a more creative expression) that can help overcome certain challenges that food formulators are faced with, either in the area of taste perception, or in other functionality areas.

Colors and Taste Perception. According to Gale D. Myers, Manager, Application Development, Sensient Food Colors, St. Louis, Mo., past studies have indicated that color can affect the threshold concentration at which the basic tastes (sweet, salty, sour, and bitter) are perceived, especially by older adults. For example, in a sweet product, the more intense the color, the more sweetness was reported by participants (although there was no difference in the sweetness of the products tested). Cakes with intensified yellow were perceived as having too much lemon flavoring, even though it actually contained no lemon flavoring. Reduced-orange-flavored drinks that had red color added to them were perceived to be sweeter and possess a stronger aroma. 

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Although these studies were conducted several years ago, their implications in the area of product development are still being discovered or rediscovered by food formulators. I think we saw several examples of this in last month’s Ingredients section on confectionery products. In particular, color can play an important role in the development of candies with super-sour or super-hot flavors. As Myers noted, the trend is to market more flavorful or extreme-flavored foods, and what better way to make the introduction to the market than by increasing the color content of the product. As the intensity of color increases, the intensity of flavor perception increases.

While Myers was primarily addressing the use of color in confections, I couldn’t help wondering if those same principles might also play a potential role in the developing of products that address health issues such as obesity. A possible idea for a future article might be “Color and Obesity.” Think about it for a moment. If color can influence the taste (and even odor) of foods—e.g., as noted above, impacting the perception of sweetness—it may play an important role in future product reformulating.

So far we’ve discussed colors that can impact taste perception without providing a basic taste, such as sweetness. How about an ingredient that can be effective in accomplishing both ends? All-natural grain ingredients that are effective colorants are available from Briess Malt & Ingredients Co., 625 S. Irish Rd., Chilton, WI 53014-0229 (phone 920-849-7711; fax 920-849-4277; www.briess.com). The ingredients, Maltoferm® malt extracts are available in a range of colors. The color extracted from barley has been malted at extreme temperatures to develop colors from golden to black. At one end of the ingredients line is Maltoferm® A-6000, a black malt extract that adds color but no flavor when used in small amounts. At the lightest end is Maltoferm 10000 which adds light golden color along with a malty flavor and aroma. Applications include bagels, bakery products, bars, beverages, cereal, granola, confections, icings, sauces, pizza crust, and many other products.

Genetic Research and Taste Perception. The Nobel Prize in Physiology or Medicine for 2004 has been jointly awarded to researchers Richard Axel and Linda B. Buck for their discoveries of “odorant receptors and the organization of the olfactory system.” The winning of this award may prove to have particular significance for the topic of this month’s Ingredients section because the olfactory system is of prime importance in food tastes. When something tastes really good, it is primarily activation of the olfactory system which helps us to detect the qualities we regard as positive.

In a series of pioneering studies since 1991, the researchers have clarified how the human olfactory system works. Using molecular techniques to decipher the olfactory system, they discovered a large family of about 1,000 genes that give rise to an equivalent number of olfactory receptor types. These receptors are located on the olfactory receptor cells, which occupy a small area in the upper part of the nasal epithelium and detect the inhaled odorant molecules.

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According to their research, each olfactory receptor cell possesses only one type of odorant receptor, and each receptor can detect a limited number of odorant substances. The human olfactory receptor cells are therefore highly specialized for a few odors. The cells send thin nerve processes directly to distinct micro domains, glomeruli, in the olfactory bulb, the primary olfactory area of the brain. Receptor cells carrying the same type of receptor send their nerve processes to the same glomerulus. From these micro domains in the olfactory bulb, the information is relayed further to other parts of the brain, where the information from several olfactory receptors is combined, forming a pattern. Therefore, we can consciously experience, for example, the smell of a lilac flower in the spring and recall this olfactory memory at other times.

As taste and smell are very interrelated, these discoveries may be of particular importance to ingredient suppliers in the area of taste perception. The researchers put it very eloquently—almost poetically—when they noted that most odors are composed of multiple odorant molecules, and each odorant molecule activates several odorant receptors. This leads to a combinatorial code forming an “odorant pattern” somewhat like the colors in a patchwork quilt or in a mosaic. This is the basis for our ability to recognize and form memories of approximately 10,000 different odors. Logically, if flavor and aroma specialists can unlock or better understand this pattern, that can have a major impact in formulating, especially in the area of taste perception.

The timing of this award is perfect when considering several of the developments described in this month’s Ingredients section. Ingredient and flavor companies are taking increasingly sophisticated approaches, such as molecular or biochemical, to taste perception. Thus, we’re seeing the development of compounds that can inhibit the bitter taste response. Or the creation of flavors that duplicate nuances that previously were not able to be captured. Or the development of new flavor enhancers and masking agents (see the August Ingredients section). Understanding the findings of the two researchers in the area of odors and how the human olfactory system is organized may help fuel new developments in taste perception.

A unique odor can trigger distinct memories from childhood or from emotional moments—positive or negative—later in life. The lilac example is a positive one. However, a single clam that is not fresh can leave a memory that stays with us for years, and prevent us from ingesting any dish, however delicious, with clams in it. This raises several interesting questions that I think would include psychological dimensions as well as physiological ones.

Recognizing that odors can trigger distinct memories can have an impact on how future foods are formulated. Perhaps the incorporation or synergistic enhancement of certain pleasant aromas and tastes can help consumers eat foods that are more healthy and pose less risk factors. Or, taking the clam example, alternative foods can be created that take advantage of different taste combinations and their interactions with each other. Reformulating foods with an understanding of smells and how they can impact taste perception may become increasingly important when trying to address the obesity problem or simply trying to create foods that will attract the consumer and not turn the person off because of some unforeseen factor.

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Gums and Taste Perception. Gums can perform a number of functions, including having an impact on taste perception in a range of foods. Furthermore,the fact that gums are generally neutral in taste means that they will not add any flavors of their own which can negatively affect the taste of the product. In an interview with Terry Van Winkle, Vice President of Sales, TIC Gums, 4609 Richlynn Dr., Belcamp, MD 21017 (phone 410-273-7300; fax 410-273-6469; www.ticgums.com), several of these properties were discussed.

Winkle explained that in beverages, for example, gums can improve mouthfeel and flavor perception, adding a lingering character to the product without adding viscosity. “Even if you don’t get a viscous sensation,” said Winkle, “you may get a lingering in the back of the mouth, or back on the tongue, so that you can get a perception of enhanced flavor or intensified flavor.”

In a savory application, such as a sauce or gravy, gums can also play an important role in flavor impact by reducing the amount of solids in a starch based system. According to Winkle, using 4–5% starch in a sauce or gravy might have a masking effect on the flavor. However, by reducing the starch to 1–2% and adding 0.5% gum, you can get the same viscosity and textural characteristics with less masking of the flavor itself.

Winkle also emphasized that the functionality of gums combined with the expertise of a culinary chef can help create products that address current trends in the marketplace. In particular, gum systems can help boost soluble dietary fiber levels and reduce the “net carbs” of the formulation. If you will recall, at the 2004 IFT Food Expo, the company’s research chef Walter Zuromski prepared and served several low-carbohydrate soups thickened with gums as replacers for traditional starches.

In a related story, TIC recently developed a gum syrup that functions similarly to corn syrup. Called TIC Pretested®Ticaloid® LC Corn Syrup Replacer, this gum acacia-based system provides 85% dietary fiber. In addition to keeping net carbs at a low level, soluble dietary fiber has also proven to be an important part of a healthful diet. The gum system has also been shown to work well with artificial sweeteners, proteins, nutraceuticals, and other ingredients common in nutrition bars and certain low-carb products.

Sweeteners and Taste Perception. Over recent months, a variety of sweetener developments have been introduced. In addition to imparting levels of sweetness, these ingredients are said to provide functionality benefits as well as health benefits which may be applicable in the areas of low-carbohydrate formulating, the addressing of the obesity problem, or the creation of foods for diabetics. The November 2003 Ingredients Section discussed in detail many new sweeteners, especially their synergistic properties, and you might want to review that article.

A year later, there continues to be interesting developments either in sweeteners themselves or in flavorings and other ingredients that are being promoted as providing sweetness with health benefits. We saw some of these developments at the 2004 IFT Food Expo. And at recent food shows, such as IBIE, AACC, and SupplySide West, several developments were launched. This section will provide a brief update on some of these developments and their use in formulating. At these shows, several prototypes were highlighted that demonstrated the impact that these ingredients has on taste perception.

Here are a few examples:

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• A citrus-derived natural sweetener available in concentrations from 100 to 600 times as sweet as sucrose was introduced at SupplySide West by The Arnhem Group, 25 Commerce Dr.,Cranford, NJ 07016 (phone 908-709-4045; fax 908-709-9221; www.arnhemgroup.com).

Called Oh! So Sweet™, the non-hydroscopic ingredient is said to impart a natural sweet flavor with a pleasant aftertaste, and enhance the taste, texture, and quality of a variety of reduced calorie foods. It has excellent solubility in water; is acid and heat stable; and has a pH of 6 in a 30% solution.

Potential applications for the ingredient, which provides no calories, no cholesterol, and very low carbohydrates, includes, in the beverage area, carbonated beverages, juices, flavored waters, milk products, light beers, coolers, and high-protein sports drinks. It may also be used in baked goods and baking mixes, ready-to-eat breakfast cereals, fillings and relishes, hard candies, frozen dairy desserts, hard candies, diabetic and healthcare products, and other applications.

It is also available in table-top packets in a consumer version. Each packet is reportedly the equivalent of two teaspoons of sugar.

The product may be classified as a natural flavor, spice, or natural extract.

• Ingredients that impart a sweet taste—a new golden syrup flavoring and new sweet brown sugar flavorings—have been developed by TasteTech Ltd., Wilverley Industrial Estate, 813/815 Bath Rd., Brislington, Bristol, BS4 5NL, United Kingdom.

The golden syrup flavorings are suitable for adding into many bakery applications, such as muffins, cookies, and Danish pastries. Other applications include hot cereals, hot drinks, puddings, cereal coatings, and sauces. According to a company representative, “Very low levels of these flavorings can also be used as sweeteners for low-calorie products, which opens up more doors for experimentation.”

The new sweet brown sugar flavorings are suitable for adding to a range of products such as cakes, confectionery items, biscuits, and breakfast bars. Available in liquid or spray-dried forms, the flavors are said to provide a healthier alternative, especially in bakery applications.

• A range of natural sweeteners for reformulating beverages so that they contain less sugar while maintaining taste has been introduced by Cargill, Inc., P.O. Box 5625, Minneapolis, MN 55440 (phone 952-742-6000; fax 952- 742-7393; www.cargill.com). Marketed under the name Special Fx, the sweeteners are said to reduce calories 33% or more without artificial or high-intensity sweeteners, while delivering the same taste profile. Delivering more sweetness with fewer calories, they are available in a range of formulations, including in combination with high-intensity sweeteners.

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In a second story, USDA has determined that trehalose may be used as a flavor enhancer in non-standardized, ready-to-eat meat and poultry products.

Cargill Health & Food Technologies had submitted study data about its Ascend™ trehalose to USDA, showing its use in several meat products. According to the data, trehalose reduces or eliminates the metallic, bitter, and astringent off-flavors associated with ingredients such as sodium phosphate, salt, potassium lactate, and sodium diacetate.

According to a company representative, “this new classification broadens the opportunities for the use of Ascend trehalose, both as a flavor enhancer and yield optimizer, in meat applications such as roast beef. In addition, ongoing plant trials are underway to identify additional benefits that trehalose may bring to meat and poultry products.”

• Ingredients that provide soluble fiber and sweetness were highlighted at AACC by Roxlor International, 1300 N. Market St., Ste. 401, Wilmington, DE 19801 (phone 302-778-4166; fax 302-778-4170; www.roxlor.com). Marketed under the name BakeFlora™ and BakeFlora HP, these functional ingredients consist of a synergistic combination of the prebiotic fiber inulin and a proprietary mung bean extract.

According to the company, the ingredients allow a reduction, or in some applications, the removal of sugar from formulations. They have a sweetness equivalent to sucrose and are often used in conjunction with sugar alcohols where they as act as flavor and mouthfeel enhancers for maltitol, sorbitol, and mannitol. They can readily be used by themselves to provide sweetness and bulking to products, as well as significantly improve the texture and mouthfeel of the products. In addition, they can provide finished products with increased soluble fiber content.

Potential applications include bakery products, ice cream and yogurt products, beverages, chocolates and hard candies, and meal replacement bar formulations.

• A natural and malty-flavored sweetener is produced by Briess Malt & Ingredients Co., 625 S. Irish Rd., Chilton, WI 53014-0229 (phone 920-849-7711; fax 920-849-4277; www.briess.com). Highlighted at the 2004 IFT Food Expo, the ingredient consists of malted barley, wheat, milk bicarbonate of soda, and salt. It can be used to flavor and sweeten such products as baked goods, bagels, sweet snacks, cappuccino, flavored milk drinks, confections, cereals, bars, and other products.

• New formulations for flour tortillas that have a reduced glycemic load and are lower in net carbohydrates are now available from Danisco Sweeteners, 440 Saw Mill River Rd., Ardsley, NY 10502 (phone 800-255-6837; www.danisco.com/sweeteners). These tortillas are made with Litesse® polydextrose, which is 1 kcal/g and adds fiber without affecting taste or mouthfeel.

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Flavor Aroma Compounds and Taste Perception. Producing reconstituted orange juice that tastes as good as the fresh-squeezed product is the goal of USDA’s Agricultural Research Service scientists in Winter Haven, Fla. The key is finding the blend of flavor compounds—more than 40 of them—that impart the taste that most consumers prefer. An article, “New Ways to Make Condensed O.J. Taste More Like Fresh,” was published in the September 2004 issue of Agricultural Research.

According to the article, the researchers are developing information about the thresholds of so-called flavor-impact aroma compounds that make fresh orange juice taste so good. A threshold is described as the minimum level at which a compound can be detected by smell or taste.

“Your taste buds may be on your tongue, but aroma compounds are perceived by the olfactory bulb in your nose. It’s accessed through the front of the nose or through the back of your throat when food enters the mouth,” said research leader Elizabeth Baldwin. “This combined orthonasal (smelling through the front of the nose) and retronasal (the aroma going to the nose through the back of the throat) olfactory testing is really important to those in the citrus industry who are trying to formulate flavors.”

Traditionally, juice processors generally squeeze the fresh oranges and use an evaporator to remove much of the water. (Condensed juice is easier and cheaper to transport or to freeze.) While the evaporative process also strips off the aroma compounds responsible for the juice’s fresh-squeezed taste, processors capture and blend these compounds into “flavor pack” mixtures. Later, juice-processing companies purchase and add these flavor packs back to frozen, concentrated juice, along with water, before marketing the reconstituted juice. The researchers are trying to develop higher-quality flavor packs that more closely mimic fresh orange juice flavor. Making less-expensive juice with fresh-squeezed flavor would improve the desirability of U.S.-processed orange juice and help it compete in the global marketplace.

To improve the flavor of orange juice, it is necessary to unravel the interactions between all the compounds in juice, which is a complex mixture. In addition to flavor compounds, juice contains sugars, acids, pulp, pectin, salts, and phenolic compounds, which can influence the perception of flavor. To understand interactions among the compounds and how they affect flavor perception, the researchers identified odor and taste thresholds of compounds considered to be important contributors to orange juice flavor. The researchers mixed the compounds into deodorized juice rather than water, and solicited the help of some 50 nonprofessional taste testers to evaluate reconstituted juices containing various orange juice flavor compound mixtures. From these results, the researchers are hoping to develop flavors that duplicate the taste of fresh orange juice for use in reconstituted juices.

The article notes that juice companies such as Tropicana, Coca-Cola North America, Florida’s Natural, and Cargill Citro-America have shown interest in the project and have offered to help find sources of orange juice aroma compounds. Several flavor companies have also been supportive.

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Bitter Blockers and Taste Perception. On September 16, 2004, Linguagen Corp., a leader in the field of taste technology, received a letter from the Food and Drug Administration indicating that it does not have any questions regarding the GRAS status of the company’s bitter blocker adenosine monophosphate (AMP). The patented compound that inhibits the bitter taste response would normally travel from the tongue to the brain—consequently stopping the brain from ever perceiving the bitter element in a food and beverage product. To put it another way, the natural compound inhibits taste buds from receiving “messages” that are translated to the brain and interpreted as bitter.

Previous issues of Food Technology have written about this bitter blocker. For example, a feature article on page 24 of the May 2004 issue focused on a biotechnological approach to the development of these novel taste modifiers. Furthermore, Ingredients sections such as those in August 2004 and July 2003 have discussed its flavor-enhancing properties and the impact that it can have in the area of food formulating.

Although we’ve covered this compound in previous issues, its relevance to this month’s ingredients topic is obvious, and worth updating for several reasons.

First, with the GRAS status accepted by FDA, the bitter blocker now has the green light to be used as a flavor enhancer in chewing gum, coffee and tea, snack foods, soups and sugar, and salt substitutes.

Second, the discovery of such a compound to control bitterness may prove more effective than conventional approaches that rely on masking bitterness with sweeteners or flavor additives. The company’s technology can identify the chemical compounds that impart bitterness to prepared foods, such as soups and sauces. Specific bitter blockers will improve flavor, without the need to add large amounts of salt or sugar.

Third, because the company biochemical approach toward understanding the mechanisms of taste, its research may lead to significant future developments in other taste areas. The company has also made major advances into understanding the perception of sweetness and creating novel compounds that will substitute for or enhance the sweetness of sugar.

For more information about these developments, write to Linguagen Corp., 2005 Eastpark Blvd., Cranbury, NJ 08512-3515 (phone 609-860-1500; fax 609-860-5900; www.linguagen.com).

Umami and Taste Perception. Umami, the perceived taste of glutamate, was the subject of a symposium held at the 2004 IFT Annual Meeting. (See side bar on page 61 for highlights.) It has been described as the fifth taste, distinct from the traditional taste qualities of sweet, sour, salty, and bitter—a view supported by research work identifying a taste receptor which enables humans to taste amino acids such as monosodium glutamate. And although the Japanese concept of umami is difficult to translate, words such as “savory,” “brothy,” “meaty,” “pungent” and “deliciousness” have been associated or equated with it. Furthermore, as Asian influences increasingly impact food formulating, the impact of umami (if not its understanding in the American vocabulary) will continue to grow—a key point, I think, in this article.

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There are two main categories of umami substances: amino acids such as monosodium glutamate and nucleotides such as IMP and GMP. Many common foods such as tomatoes, eggs, seafoods, and especially fermented foods, including cheese, fish products, and soy sauce, contain active umami substances.

“The ability to taste amino acids guides us to proteins, which themselves have no taste,” noted a taste researcher at Saarland University, Homburg, Germany, who was recently quoted in Nature. Glutamate, for example, is a common amino acid giving high-protein food its meaty, “umami” flavor.

Interestingly, not all amino acids are the same. Glycine and alanine have a sweet taste, valine and leucine have a bitter taste, and aspartic acid and glutmate have sour and umami tastes. Though called a bitter amino acid, valine has a slightly sweet taste as well. Combination of amino acids with their respective tastes is a key determinant for the taste of food. Relationships between amino acids and taste have been explored since the discovery of glutamate as a umami ingredient. Determination of amino acids contained in foods revealed that the taste we perceive largely depends on the kinds and amounts of the amino acids.

Particularly significant is the fact that umami substances are synergistic—when used in combination, their taste is amplified. (See the February 2004 Ingredients section for a discussion of proteins and amino acids.) According to researchers, this synergism creates a desirable taste which helps motivate individuals to eat a balanced diet, including the consumption of essential amino acids. Umami substances in certain foods such as aged meats and fish can help make vegetables taste better.

As I noted in a previous Ingredients section on flavor enhancers, many studies are looking at the synergistic abilities of flavor-enhancing substances, and how these abilities amplify flavor enhancement. Future studies will probably underscore how these synergies work. Interestingly, many of the traditional descriptors used when talking about “umami,”although not incorrect, may still prove to be somewhat limiting because we’re actually talking about synergy—or the equation 1 + 1 = 3 that mathematically doesn’t make much sense. As such, it can be difficult sometimes to pinpoint precisely the kinds of tastes that will emerge in the final product.

Furthermore, to make things even more complicated, the basic tastes are very interrelated. For example, just as salt can suppress bitterness so that more sweetness comes through in the finished product, so can umami affect the other tastes by suppressing or enhancing them, depending on the dosage level used. For example, according of the International Glutamate information Service, the worldwide organization of glutamate associations and a source of up-to-date information about glutamate and its many benefits, research has shown that people find food with low levels of salt much more acceptable when a small amount of MSG is added. One study evaluated people’s responses to different versions of a clear soup, with and without MSG and with different levels of salt. Without the addition of MSG, the soup did not become palatable until the salt concentration reached 0.75%. With MSG, however, the soup was palatable with a salt concentration of only 0.4%.

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Because the basic tastes, including umami, are so related to each other, each potentially having an impact on the other and consequently on the overall product, perhaps the way we view the basis tastes as a unit should be reviewed. The visual concept of umami as sort of a distinct satellite to the basic tastes which themselves are distinct should be revised (as probably every chef and food formulator probably knows anyway). In a product formulation, the different tastes, especially as they relate to each other, are not that simple or distinct. Rather, many complex relationships between the different tastes are possible, as well as a broad range of taste combinations—sweet and salty, salty and sour, cool and sweet, hot and umami, and so on.

Perhaps the most mind-blowing aspect of umami (sort of like going through that portal in 2001: A Space Odyssey) is that some studies are suggesting that the experience of umami is a result of glutamic acid working synergistically with olfactory sensors (i.e., those old taste buds are being helped along by a sense of smell). If so, put that into context with the Nobel Prize-winning research work on odorant receptors and the organization of the olfactory system, and the possible implications as they relate to food formulating are really exciting. And if you want to take it to still another dimension, some researchers, especially those from other cultures, associate umami with emotional, spiritual, or mystical qualities. God and umami? I’m not sure about that, but certainly as we saw in the Nobel Prize–winning research, certain smells (and tastes) can bring back certain memories, which can have both positive and negative implications. These implications can then have an influence on our psychological—or spiritual—make-up. So next time you formulate with umami-producing substances, keep all that in mind.

Not too surprising, several ingredient developments are being promoted as offering a umami taste or enhancement of taste. Here are just a few examples:
• A yeast-based ingredient for taste enhancement was introduced under the name Umamex™-XLM by Kerry Bio-Science, A Kerry Company, 5115 Sedge Blvd., Hoffman Estates, IL 60192 (phone 800-263-8799; www.kerryamericas.com).

The latest addition to the company’s taste-enhancement range of yeast specialties, the ingredient reportedly provides a clean flavor profile, low-yeasty impact, and controlled time-release of flavor for a wide variety of savory applications and processing conditions. According to the company, it is designed specifically to enrich the taste profiles of soups, sauces, ready-to-use meals and noodle seasonings, while delivering mouth-watering effect. At the 2004 IFT Food Expo, the ingredient’s umami effect was demonstrated in a prototype application, Crispy Crab Rangoon.

• A new flavor that contributes “kokumi,” a Japanese term meaning a mixture of different tastes or mouthfeel characteristics, is available from Riken Vitamin Co., Ltd., 800 E. Northwest Hwy., Ste. 724, Palatine, IL 60074 (phone 847-705-2126; fax 847-705-7024; www.rikenvitamin.com). Called Belex Super 1000, the product is suitable for use in frozen foods, soups, sauces, dressings, snacks, and various other processed foods. According to the company, the product encompasses the basic tastes as well as umami.

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• A wheat-derived ingredient providing umami properties is available under the name NFE-S from Kikkoman International, Inc., Industrial Dept., P.O. Box 429784, San Francisco, CA 94142-0784 (phone 415-956-7750; fax 415-391-1842; www.kikkoman-usa.com). Made from fermented wheat protein, it is produced using specific microorganisms and enzymes in a natural fermentation process similar to the process used to make naturally brewed soy sauce. The resulting product is then spray-dried to yield a powdered flavor enhancer that is high in amino acids, particularly glutamic acid and short-chain peptides. The powdered ingredient, which has a neutral, light golden tan color and a mild aroma, is said to give a clean, balanced, brothy umami flavor to a variety of applications. It may be used to heighten or round out the flavors of seasoned poultry, meat products, seafood, soups, snack mixes, marinades, and other products.

• Umami-active ingredients for a variety of applications are available from Ajinomoto Food Ingredients LLC, Country Club Plaza, West 115 Century Rd., Paramus, NJ 07652-1450 (phone 201-261-1789; fax 201-261-6871; www.ajiusafood.com). Ajinomoto, which moderated the symposium, “Old Story, New Twist: Umami and Amino Acids,” presented at the 2004 IFT Annual Meeting, produces Ajinomoto Monosodium Glutamate (also called Ajinomoto Umami), for use as a flavor enhancer in such processed foods as meat, poultry, and vegetable entrees; soups, sauces, and gravies; and snacks. The company reportedly has the only MSG-producing facility in the U.S. It also offers Ajitide Nucleotides (IMP, I+G) for use as flavor enhancers.

Genetic Research and Taste Perception– Part 2. In this article, we are looking at a number of ingredients that can have an impact on taste perception—whether they actually impart a particular taste sensation (e.g., salt) or do not impart a taste sensation (e.g., color). Now consider the possibilities of combining an understanding of these ingredients with some genetic research currently being conducted, and we may find that we have—or will have—some very interesting results.

According to Monell Chemical Senses Center’s newsletter (Summer 2004), genetic research has an important role in the investigation of flavor preferences that may contribute to the over consumption of food, and subsequently in the genesis of obesity. Some variations in body weight and food and drink preferences come from the unique experiences of each person, such as environment, food availability, or culture. Additional variability between individuals is inherited from parents.

Research is being done to locate and identify the specific DNA variants that contribute to these individual differences. Such research, for example, has helped Monell scientists to identify the Sac gene, a human receptor for sweet taste. This research is said to be essential to understanding how individuals perceive, select, and consume food, offering potential solutions for those at risk for obesity and other health-related problems.

When combining the above genetic research with studies on the uses of salt, sweeteners, colors, gums, and other ingredients in impacting taste perception, it’s possible that we’re collecting useful information that can then be applied to the development or reformulation of food products that might better confront obesity and health problems related to it.

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Flavors and Taste Perception. A new line of flavors which are said to capture the nuances that are not identified through traditional analytical methods has been launched by Takasago International Corp., USA Flavor Div., 4 Volvo Dr., Rockleigh, NJ 07647 (phone 201-767-9001; fax 201-784-7277; www.takasago.com). The flavors, first discussed in the October 2004 Ingredients section, are called Vivid Flavors™ because their true-to-life tastes are created through an entirely unique way of identifying the precise chemical composition of the flavor that the company wants to replicate.

According to company representatives, the development of the flavors was the result of a global effort, integrating all of Takasago’s technologies, including ingredients based on the company’s chiral chemistry. “Chiral compounds can be created to be identical to those found in nature, and therefore, allow the flavorist to create the subtleties found in aroma and taste characteristics that maximize the perception of the flavor, particularly in their use in complex food and beverage applications.”

The line of flavors, which deliver the tastes of real fruit, includes peach, Concord grape, Fuji apple, strawberry, and raspberry. Of particular relevance to this article, however, is the fact that new flavors are currently being developed (and according to one source will soon be launched) that will duplicate savory and sweet tastes using the method that was applied to the initial fruit flavors. Such flavors will create new opportunities in the area of taste perception as well broaden application use.

In a related story, at the company’s Sensoral Center of Excellence, researchers are studying materials that stimulate the trigeminal cavity, a complex system within the human body. The term “trigeminal” refers to a pair of nerves that rise from the cerebellum and separate into three separate nerve divisions in the face, oral cavity, and nasal cavity. The system has been found to function as a key element of the body’s ability to recognize and identify sensory properties of certain components of foods and substances approved for use as flavor ingredients. It sounds like the work being done there will have impact in the area of taste perception.

Acidulants and Taste Perception. A powdered product, natural L (+) lactic acid on a calcium lactate carrier, has been introduced under the name Purac Powder by Purac America, Inc., Ste. 100, 111 Barclay Blvd., Lincolnshire, IL 60069 (phone 800-423-0457; fax 847-634-1992; www.pam.com). Because the ingredient is available in a convenient, high-quality powder form, its applications have been extended to include a wide range.It offers flavoring opportunities for cheese and other dairy-flavored foods, seasonings for sour cream and onion potato chips, dry mixes for dips and salsas, gravies, instant noodle soups, soy- or stock-based mixes, and acid sanding of soft candies.

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The stable, free-flowing powdered ingredient at low concentrations reportedly has the same mild sourness that is associated with lactic acid in its liquid form. However, when applied in sour sandings for soft candies, the powder provides an extreme sour boost. A mix of 10–15% powder, combined with 85–90% sanding sugar, generates a direct sour boost in acid-sanded gums. In the October 2004 Ingredients section, I mentioned how intensely sour candy has become increasingly popular for younger tastes, and ingredients such as this one would probably be applicable for that category.

When you think of lactic acid, degree of sourness probably comes first to mind, so the above examples are probably not that surprising. However, lactic acid can also have an impact on other taste perceptions, especially in Asian dishes. For example, a Chinese sweet-and-sour sauce an demonstrate that lactic acid enhances the overall flavor and particularly the sweet-tomato and the salty-onion components. Studies have shown that it’s possible to replace some monosodium glutamate with lactic acid powder. Lactic acid can also be used to enhance the creamy and cheese notes in a cheese sauce or dairy seasonings.

Encapsulated Ingredients and Taste Perception. A variety of encapsulated ingredients which overcome functionality challenges while providing basics tastes are available from Balchem Corp., 52 Sunrise Pk. Rd., New Hampton, NY 10958 (phone 877-222-8811; fax 845-326-5717; www.balchem.com). The following applications were all highlighted at the International Baking Industry Exhibition (IBIE).

Encapsulated ingredients used on product surfaces offer protection against high-moisture conditions and freeze-thaw abuse. For example, encapsulated pretzel salt and encapsulated nonpareils offer advantages over conventional products. According to the company, a high-melt coarse salt, compared to raw salt, shows excellent performance in freezer-to-oven parbaked pretzel dough, while the shelf life of decorated products can be extended with encapsulated nonpareils which retain their shape and color in these conditions. Pretzels with Bakeshure pretzel salt and muffins topped with Bakeshure decorative sugar were featured.

In confectionery applications, a thin coating can be applied to the surface of a sour candy; this prevents moisture pickup while dissolving in the mouth for an acid burst. While acidulants are integral to the extremely popular sour candy category, they are also highly vulnerable to production and storage factors. With Confecshure encapsulation, which uses partially hydrogenated vegetable oil, flavor and shelf life can be maximized while taking sour to a whole new level. Highlighted were sanded candy with encapsulated acids.

The company recently introduced Confecshure Burst, an encapsulated ingredient which delivers a popping sensation coupled with a discrete and distinct flavor that complements or contrasts the flavor of the base product.

Vitashure encapsulated ingredients may be used in fortified applications to mask undesirable flavors, such as bitter off-notes, and odors associated with certain nutrients. The encapsulation technology controls release of the wellness ingredients, protects the ingredients from degradation and undesirable interactions, brings improved stability and longer shelf life, and delivers consistent nutritional performance. Fortified cookies with Vitashure nutrients were displayed.

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Antimicrobials and Taste Perception. An antimicrobial which is said to have very little effect on the taste and texture of the application has been introduced by A&B Ingredients, Inc., 24 Spielman Rd., Fairfield, NJ 07004 (phone 973-227-1390; fax 973-227-0172; www.abingredients.com). Marketed under the name Mirenat®-N, the antimicrobial is said to be heat and pH stable, and can be used in a broad variety of processed foods such as meat products, ready-to-eat foods, and juice beverages.

According to the manufacturer, a much lower dosage of the product is needed in comparison to other antimicrobials, and therefore it has very little effect on the taste and texture of the original product. It does not impact the sodium or acidity of the food in which it is used and will not be affected by most food processes, including UHT and pasteurization. The product is highly effective in controlling a wide range of microorganisms, including Salmonella, Listeria monocytogenes, Escherichia coli, Lactobacillus, and numerous other pathogens, bacteria, molds, and yeast.

Genetic Research and Taste Perception–Part 3. Earlier, this article discussed some genetic research work being done at the Monell Center which may have relevance in the area of taste perception. In the February 24, 2003, issue of the Washington Post, an interesting article discussed research being done with “supertasters”—individuals born with a genetic trait that makes them extremely sensitive to certain tastes.

According to the article, these supertasters provide researchers with a window into understanding how the sense of taste works. Furthermore, work is being done to determine whether these individuals “are more or less prone to certain diseases because their hypersensitivity to certain flavors makes them more or less likely to eat foods that can increase or decrease risk of disease.” For example, their strong aversion to bitter tastes may make them avoid certain vegetables which can lessen their risk for cancer. On the other hand, their distaste for fat and alcohol may make them less likely to develop heart disease.

This research may lead someday to doctors’ testing patients’ sensitivity to certain tastes, and based on the results, helping develop diets that are more palatable to them. Although this article focused on supertasters—a small segment of the population—I found this article interesting because some of the results or approaches used might also apply to the general population. For example, someday an individual (younger the better) may be tested to determine a number of factors, including taste preferences and risks for certain diseases. Based on the profile developed, improved counseling in nutrition can be given and food guide pyramids can be customized to meet the needs of that specific individual. In that sense, supertasters may help pioneer that future frontier. Also, as the article pointed out, the ultimate goal would be to provide diets that are more palatable to the supertasters. That should also be the ultimate goal for the general populace, and in that sense, ingredient suppliers can play an important role in reformulating foods to meet both the taste and health needs of individuals, whether they’re supertasters or not. If you take such a perspective, the title of the article, “Could Health Risks Be Nipped in the Taste Buds?” poses a very interesting question in relation to future formulating.

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Having lived in Chicago most of my life, I frequently feel that we do not have four seasons, but actually 12—one for each month, with the weather of each month overlapping that of the previous one. And sometimes nature has its jokes, offering combinations that are not always satisfying to the finished product—our life experience—and not always entirely expected. I have come to view the basic tastes and the exploration of them in product development much the same way as I view Chicago’s wheather. Interesting question in relation to future formulating.

After having written this article, have come to realize again that when talking about the basic tastes, we have a lot more than four (or five, if you count umami, as I think you should) tastes to consider. In fact, if I was writing a book about new developments in the area of taste perception, each chapter would be about a different taste combination: sweet and salty; sweet and sour; hot and sour; sweet and bitter; umami and salty; umami and sweet; salty, sweet, and bitter; and. . . so on.

And in each category, one would have to consider how the other senses as well as other ingredients in the formulation impact taste perception and the overall quality of the finished product. And just like Mother Nature sometimes gives Chicagoans a drought in rainy April or very cold weather in humid June, so does a food formulator sometimes arrive at an unexpected result. Hopefully, like Mother Nature, he or she quickly gets back on the right track.

The point here is that the basic tastes have complex relationships in a formulation—not only with themselves but with other ingredients as well. And, of course, other factors such as the sense of smell or the use of ingredients, such as gums, colors, flavors, and flavor enhancers, while they do not necessarily provide a basic taste sense, still can have a major impact on taste perception.

While combining contrasting flavors or basic tastes is not really new (I was eating sweet-and-sour pork when I was a kid), I think we’re seeing more and more food development work being done in this area. For example, the summer 2004 newsletter published by TreeTop, Ingredients Div., P.O. Box 248, Selah, WA 98942-0248 (phone 800-367-6571; www.treetop.com) focused on contrasting flavors, such as plum, ginger, mango, and hot peppers, in frozen dinner entrees. With a broad selection of fruits available to product developers, many have enhanced the sensory experiences of frozen entrees by layering a blend of fruit notes with other spicy ingredients. The newsletter noted that Mintel Global New Products Database posted 106 new product introductions in the retail meal or prepared meats category that used apple as an ingredient to enhance the savory experience.

In last month’s Ingredients section on confections, we saw a number of different taste combinations. Ideally, the developments described in this month’s Ingredients section will help shed further light on this and other aspects of the taste perception area. And in upcoming Ingredients sections, we’ll be seeing more examples of taste combinations and the work being done in the field of taste perception.

Some of these developments may help change the way we traditionally view the basic tastes, the roles they play in food formulating, and the ingredients used that will impact the overall taste perception of the final product.

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Symposium highlights umami and amino acids
Umami and amino acids was the subject of a symposium held at the 2004 IFT Annual Meeting. The symposium, “Old Story, New Twist: Umami and Amino Acids,” was cosponsored by the IFT oxicology and Safety Evaluation Div. and Food Laws & Regulations Div., and was moderated by a representative of Ajinomoto USA, Inc.

Attendees were updated on scientific research regarding the umami taste receptor; the human perception of umami; and food safety, metabolism, and worldwide regulatory status of amino acids and umami substances. It would be impossible to summarize the entire symposium, so the following are highlights of the presentations.

• Jacqueline B. Marcus, Food & Nutrition Consultant, Northfield,Ill., spoke on culinary applications of flavor enhancement in product development. She noted that while Asian cuisine is based on traditional umami-rich ingredients for deliciousness, American/European cuisine has few traditional umami ingredients, but rather favors fat for richness and fullness. According to a quote by a chef, “Westerners have a lineal palate, set up on sweet and salty taste with few counterpoints and harmonies. In Asian cuisine, however, you use all tastes at the same time. You’re eating circularly. You must train your mind to go after flavor characteristics and look for flavors in different parts of your mouth.”

Marcus discussed the practical aspects of umami, which includes providing a home-made flavor; intense, rounded-out flavors, and a savory taste. It can drive appetite for protein-rich foods, highlight sweetness, lessen bitterness, and contribute to sodium reduction. It can be particularly effective in sodium-reduced foods and diets. Some examples of umami-rich foods that Americans would quickly recognize would include Caesar salad/dressing; pizza and pasta; French fries and catsup; fish sauce/fish paste; and fresh sweet peas and corn. The enhanced smell and taste of umami-rich ingredients stimulates the palate implies strong flavors and increases tasty, nutritious food choices.

Umami-active ingredients can affect taste perception in a number of ways. For example, soy sauce can enhance sweetness in bitter foods-balance acidic taste, and increase umami in tomato products. Parmesan cheese can bring out sweetness in bitter foods and add depth to sour dishes. Anchovies/smoked fish can bring out sweetness in pasta, butter, and bitter foods such as cauliflower, zucchini, and fennel, and boost umami when added to steak, fish, poultry, and tomato sauce. Addition of tomatoes or tomato sauce can bring out sweet, sour, and salty tastes, while balancing bitter taste. Sweet foods increase perception of acidity in wine

As a flavor partner, umami can create something new or superior to the original product. For example, the taste of a standard seafood bisque can be enhanced by combining seafood (with umami) and fortified wine and umami-rich mushrooms.

As a flavor layerer, umami can help different flavors peak at different times. A umami-enhanced cocktail sauce can be created by adding wasabi, soy sauce, and lemon to a tomato-based sauce. Umami is boosted for a hot/savory unified finish.

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As a flavor balancer, umami highlights flavors by contrasting, canceling, or balancing. Umami-rich ingredients balance strong ingredients, mellow sharpness, and highlight hot/savory/sweet taste. These benefits were shown in formulations containing Chinese five-spice powder, Asian sauce (with umami), and sugar, as well as garlic, ginger, soy sauce (with umami), and sugar.

As a flavor catalyst, umami provides backbone flavor, and keeps primary flavors from disappearing. Aged beef and truffles (both with umami) provide backbone flavor while lifted by lemon and salt.

• Kees de Graaf, Wageningen University, Netherlands, spoke on chemosensory sensitivity, flavor enhancement, and food intake in the elderly. Inadequate dietary intake is common in the elderly, especially for those living in institutions such as nursing homes. One potential cause of inadequate intake is a loss in appetite related to an impairment of the sense of taste and the sense of smell. One strategy to compensate for the taste and smell losses is to amplify the chemosensory signals in the food. Earlier studies showed that the elderly prefer higher concentrations of taste and smell substances in foods. De Graaf reported on the results of a study which determined whether the addition of appropriate flavors, monosodium glutamate alone, or a combination of MSG and appropriate flavors resulted in an increased food intake, a better nutritional status, and a better quality of life in nursing home elderly.

• Sue C. Kinnamon, Colorado State University, Fort Collins, Col., and Rocky Mountain Taste and Smell Center, University of Colorado Health Science Center, Denver, Colo., spoke on identification and characteristics of umami taste receptors.

T1R1 + T1R3 is the umami receptor that exhibits nucleotide potentiation. In humans, this receptor is highly tuned to glutamate, but in rodents it is broadly tuned to amino acids. Additional receptors likely contribute to umami taste. These include the putative truncated glutamate receptors, mGluR4 and mGluR1, as well as additional receptors for nucleotides.

Umami taste receptors couple to a heterotrimeric G protein consisting of α-gustducin and its partners β3 and γ13. Gustducin decreases intracellular cAMP, while its partners stimulate PLC to cause increases in intracelluar Ca²⁺ These increases presumably lead to transmitter release and activation of gustatory afferent fibers.

• E.T. Rolls, Dept. of Experimental Psychology, University of Oxford, England, spoke on representation of umami taste and the human brain. Single-neuron recordings in primates (macaques) show that there is a representation of umami taste which can be activated by monosodium glutamate, glutamic acid, or inosine 5'-monophosphate in the mouth, in the primate primary and secondary taste cortex.

• John D. Fernstrom, University of Pittsburgh School of Medicine, spoke on the safety and regulatory status of umami substances. He noted that clinical studies have failed to identify a reproducible syndrome in humans reporting sensitivity to MSG. Moreover, reproducible, dose-related adverse effects of MSG have not been found in such individuals, following double-blind, oral dosing at high levels. Consequently, ongoing research and review continue to support the safety of the amino acid in the food supply.

Next month’s Ingredients section will look at how strategic alliances with ingredient suppliers are affecting the product development landscape.

by DONALD E. PSZCZOLA
Senior Associate Editor
[email protected]