Donald Pszczola

Donald E. Pszczola

If there were zodiac signs for ingredients, proteins might well merit one. While officially we might be in the Age of Aquarius, from an ingredients perspective, I would say we’re definitely in the Age of Proteins. And based on the many developments (both functional and health-related) that this article will cover, I think I can safely say that this age is only beginning—one might call it the dawning of the age of proteins.

Meat stocks in a variety of forms can provide a valuable source of protein as well as a traditional, home-made flavor.Proteins are the principal material—or building blocks—of which animals such as we humans are made. Chemically, proteins are complex organic compounds made up chiefly of amino acids. Proteins in the food are broken down into amino acids by digestion. They are then absorbed and distributed by the blood-stream to the body cells, which rebuild these amino acids into body proteins. Each specific protein performs a specific function in the body. Generally speaking, these functions include the formation of new tissues from infancy to adulthood; maintenance of body tissues; regulation of body processes; milk production; and production of energy. Proteins also function as hormones, enzymes, and antibodies.

Since humans cannot make proteins the way plants do, they need to eat animals or plants to get the necessary protein to provide the vital materials for the growth and repair of their bodies. According to one of my reference sources, The Oxford Companion to Food, proteins which contain all the essential amino acids in the proportion in which they are needed are more valuable as foods than those which lack or do not have enough of a vital component. As such, foods of animal origin are generally considered more valuable than foods of plant origin. However, by eating a balanced diet, it is also possible for different foods to complement each other, providing together the necessary amino acids that the body needs.

Because of their importance to human health, proteins have played a major role in food formulation. However, there are several reasons why proteins are taking more of the spotlight these days. One obviously has to due with the increasing emphasis on developing high-protein, low-carbohydrate food products. Since next month’s Ingredients section will be discussing a range of ingredients that might find application in these kinds of foods, I will not be focusing too much on that point in this article. It isn’t difficult to guess, though, that such an emphasis is having an impact—short-term or longer—on product development.

With the current emphasis on the formulation of high-protein, low-carbohydrate food products, a number of studies which have looked at the health benefits of proteins are being reinvigorated as well. For example, the Whey Institute, Eden Prairie, Minn., released a research update of recent whey protein studies demonstrating benefits to human health. Areas that these studies looked at included weight management, breast cancer, muscle loss among the elderly, and prostate cancer. These studies will probably spark other studies, and not surprisingly, expand the use of protein ingredients such as whey in product formulation. See the Nutraceuticals & Functional Foods sections for ongoing and detailed coverage of the health benefits of proteins.

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An interest in health is not the only impetus for the use of proteins in product development, however. The functionality of proteins also plays an important part in the success of these ingredients. For example, proteins can have an impact on gelation, viscosity, film formation, water control, taste, and many other areas that are important to the formulation.

Furthermore, new advancements in technology are helping to customize these ingredients, making them applicable for specific applications for which otherwise they might not have been suitable. For example, meat applications will require characteristics of proteins that are different from those of beverages or nutrition bars. Consequently, proteins are being fractionated, isolated, concentrated. Their availability is being enhanced by new extraction and purification methods. They are being modified by various traditional and not-so-traditional treatments. And new sources of proteins are being looked at which technologies can unlock. This is certainly a very exciting time for protein technology, which will help spur new ingredients for product development.

Many of the developments discussed in this article will focus on the functionality of proteins. I will also be including in this “protein portfolio” some health-related developments, especially as they relate to the functionality of the product. We will be looking at proteins from a variety of sources, including eggs, grains, dairy, fish, soy, and others. Included in our roundup will be new developments in gelatin, which is protein-based, made by boiling down bones, skin, and meat trimmings, all containing collagen.

With that, let’s review some of the significant protein developments over the past 18 months:

Gelatin Replacer Wins FIE Award. A protein-containing whipping and stabilizing agent for the preparation of ready-to-eat aerated desserts earned FI Europe’s first-place award for “Most innovative food ingredient 2003.” Called Textrion Gel 01, the ingredient has been especially developed for the creation of gelatin-free chocolate or vanilla mousse by DMV International, P.O. Box 13, 5460 BA Veghel, The Netherlands (phone 31-413-372-222; fax 31-413-343-695; www.dmvinternationalcom).

The ingredient, which consists of an emulsifier, vegetable fat, glucose syrup, and milk protein (5.5%), is said to enable the manufacturer to create gelatin-free mousse with the physical stability and sensory properties of mousse containing gelatin. During processing of the mousse, the ingredient shows similar shear and temperature reversible properties as gelatin. It provides milk-based mousse with a smooth texture, fine air bubbles, a good melting behavior in the mouth, and a bland taste.

A report, “Textrion Gel 01: The Next Generation in Gelatin Replacement,” is available, along with information regarding legal status, labeling, application, and handling.

In addition to the award-winning ingredient, the company supplies a whole range of functional products for ready-to-eat desserts, including topping bases for mousses and a series of economical milk-solid nonfat sources for sweet desserts.

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Vatless Cheesemaking Captures Whey Proteins. A new cheesemaking process which can capture valuable milk proteins has been developed by researchers at Cornell University, Ithaca, N.Y. The process is said to leverage a combination of membrane filtration systems and coagulators instead of the traditional vats that cheesemakers have relied on.

The “vatless” system facilitates the production of Mozzarella-type cheese on a continuous basis, enabling cheesemakers to meet growing consumer product demand while capturing the pure milk proteins that are becoming increasingly valuable in nutraceutical applications.

In the traditional vat process, 9 lbs of whey and 1 lb of cheese are produced from 10 lb of milk. Cheesemakers then process the whey to create functional ingredients for food manufacturing, such as whey protein concentrate, isolates, and others. Using microfiltration and a coagulator, lead researcher Syed Rizvi was able to efficiently produce a mozzarella-type cheese from a smaller quantity of microfiltered and concentrated skim milk.

According to Rizvi, “with the microfiltration process, dairy processors can filter liquid milk to remove serum proteins prior to using the milk in cheesemaking. Depending on whether the goal of the process is to make a concentrated milk-derived ingredient rich in protein, or to separate individual components from the milk, the filters can be adjusted accordingly, yielding a customized fluid permeate and a customized retentate.”

The microfiltration process produced a high-concentrate casein retentate, to which was added rennet and a starter culture. The resulting cheesemilk was then pumped into a coagulator, and the curd was cooked, salted, and stretched.

Emerging research indicates that milk-derived proteins may prove beneficial for weight management and the regulation of food intake, hypertension, and muscle metabolism. New and improved fractionation methods, such as the microfiltration process, provide a means to isolate the healthful components in milk and incorporate them into the new products that consumers are beginning to demand.

In a related story, the Dairy Council Digest (November/December 2003) provided a detailed look at the emerging health benefits of whey. Whey protein consists of several different proteins, including beta-lactoglobulin, alpha-lactalbumin, immunoglobulins, bovine serum albumin, lactoferrin, and lactoperoxidase, as well as glycomacropeptide, a casein-derived protein in cheese whey. As a result of new technologies, a variety of biologically active amino acids, peptides, and fractions can be isolated from whey protein.

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The digest noted that findings from in vitro, experimental, and limited human studies suggest beneficial bioactivities of whey and whey components. Several whey proteins, including lactoferrin and its peptide derivative lactoferricin, have been shown to inhibit the activity of a diverse range of microorganisms, including some harmful foodborne pathogens. Specific whey proteins also exhibit antiviral activity against human immunodeficiency virus and other viruses, and stimulate the immune response to a variety of antigens. An anti-cancer activity has been described for whey components such as protein (e.g., lactoferrin, lactoperoxidase, alpha-lactalbumin, and conjugated linoleic acid in whey lipids).

For more information about these developments, write to Dairy Management, Inc., 10255 W. Higgins, Rosemont, IL 60018 (phone 847-803-2000; fax 847-803-2077; www.doitwithdairy.com).

New Source for Proteins. Innovative technology for extracting protein isolates from canola/rapeseed meal has been developed by Burcon NutraScience Corp., 1946 W. Broadway, Vancouver, B.C., Canada V6J 1Z2 (phone 604-733-0896; fax 604-7333-8821). The successful commercialization of this process may offer an alternative source for protein ingredients that exhibit valuable nutritional, functional, or nutraceutical properties.

A research and development company, Burcon NutraScience Corp., used the extraction process to separate protein from fiber and other components in the canola meal, yielding the world’s first commercial canola proteins called Puratein® and Supertein®. The company expects that these proteins will have special functional qualities that will make them useful as food ingredients, and that they will possess special amino acid profiles that differentiate them from soy- and animal-based proteins.

Initial analysis of the canola protein isolates indicated foaming and whipping properties, gel-forming ability, water-and fat-binding properties, and emulsification qualities, making them potentially useful in cakes and pastries, veggie burgers, protein drinks, protein bars, and many other food products. One of the protein ingredients, Supertein, also exhibited good solubility in an acidic setting such as fruit juice, and has stable, low-level viscosity.

Physical characteristics of the protein ingredients include a golden color, little or no odor, slightly grainy flavor when dry, and a slight tangy taste in liquids. The ingredients are free-flowing powders that are not expected to require refrigerated storage.

The company recently announced that it has entered into a licensing and development agreement with Archer Daniels Midland Co. to commercialize protein ingredients extracted from canola. The licensing and development agreement outlines the process by which the two companies will carry out the final development of the technology to produce the canola protein isolates, as well as special grades of the products and their derivatives. The agreement contemplates that ADM will develop applications for the products, obtain regulatory approvals, construct one or more full-scale production facilities, and have the exclusive right to produce, promote, market, and sell products worldwide.

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Beverage Fortified with Hydrolyzed Protein. A black cherry beverage prototype fortified with a hydrolyzed whey protein called Grande Ultra 8020 was developed by Grande Custom Ingredients Group, 301 E. Main St., Lomira, WI 53048 (phone 920-269-7188; fax 920-269-1445; www.grandecig.com). The company is reportedly able to hydrolyze the proteins for improved absorption and digestibility with minimum bitterness and a mild flavor.

Whey proteins marketed under the Ultra line are produced using an exclusive three-step cold filtration process, and include Grade A, instantized, reduced-lactose, and heat-stable versions. Applications include beverages, bars, and many processed foods. Samples and formulas are available.

Also available from the company is the Grande Bravo line of functional whey proteins for use in bakery applications such as cookies, brownies, cakes, muffins, cheesecakes, pies, and fresh and frozen doughs. These whey proteins are said to help improve shelf life and freeze-thaw stability, yield low-fat or reduced-fat products, improve texture, and increase volume. In these bakery formulations, they can extend specific ingredients such as cream cheese, replace or reduce ingredients such as milk solids, eggs, and shortening/oil, or be used in addition to the other ingredients.

Wheat Proteins Help Improve Dough. A specially formulated line of wheat protein isolates for bakery products is available under the name Arise™ from MGP Ingredients, Inc., P.O. Box 130, Atchison, KS 66002-0130 (phone 913-367-1480; fax 913-367-0192; www.mgpingredients.com). The ingredients are designed to enhance the production and performance of dough in a variety of systems—fresh, par-baked, refrigerated, or frozen.

Arise 5000 is promoted for use in frozen and refrigerated dough systems to help control water migration during the freeze-thaw process, increase freshness, and extend shelf life in finished goods. Because of its film-forming properties, it can serve as a moisture and fat barrier to enhance the crispness of bakery products.

Arise 6000 possesses high extensibility and provides excellent rheology modification, making it suitable as a functional protein for use in par-baked bread, frozen bread dough, and other applications. It can improve color, crust, and texture, and provide better, more consistent loaf symmetry.

The company makes available a variety of other wheat protein ingredients. Wheat gliadin is the protein fraction of wheat gluten soluble in 70% alcohol at room temperature. It is very extensible and delivers film-forming properties.

HWG™ 2009 is a mildly hydrolyzed wheat protein that provides good solubility and neutral flavor. Rich in peptide-bonded glutamine, it has applications in nutritional products and, when incorporated into dough systems, can reduce mix time.

The company also continues to expand its line of Wheatex textured wheat proteins. Produced in multiple sizes and shapes ranging from small, crumb-like particles to shredded pieces and large flakes, these ingredients are sold principally for use in meat replacement and meat extension applications. They can also be used in the production of protein-enhanced snack foods and other grain-based products.

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Milk Proteins Enhance Texture of Bars. Milk proteins, developed to improve the quality of protein-enhanced bars, are available from Kerry Ingredients, 100 E. Grand Ave., Beloit, WI 53511 (phone 608-363-1200; fax 608-363-1670; www.kerryingredients.com). The ingredients, marketed under the names Ultranor ST and Optimal ST, are prepared using a modified ultrafiltration process that alters the protein structure to minimize water absorption, producing a softer-textured bar and extended shelf life.

Ultranor ST is a casein-dominated milk protein concentrate that contains 80% protein with a casein-to-whey ratio of 95:5, which enhances bar nutrition and produces a softer bar matrix. It maintains a softer texture and increases shelf life in bars while allowing reduction of glycerine inclusion by up to 30%. The ingredient is isolated from fresh nonfat milk, making it a virtually lactose-free dairy ingredient containing 2.7% natural-milk calcium, which is more easily absorbed by the body than some other calcium sources.

Optimal ST, concentrated from fresh whey, contains a minimum of 75% protein and 10% lactose. It has less gelling capability and lower water-binding capacity compared to standard whey protein concentrates, resulting in a softer bar over prolonged shelf life.

Both ingredients possess a clean, slightly milk taste and will not mask other flavors. They deliver functional benefits, even when used in combination with one or more other protein sources, which allows for greater flexibility in product development and label declarations.

Applications for these ingredients include extruded and baked bars, such as meal-replacement, sports-nutrition, and weight-loss products. In cracker-type snacks, the proteins can produce softer dough for better extrusion and extended shelf life by minimizing atmospheric moisture absorption during storage.

Formulations Demonstrate Functionality of Whey Proteins. New technical advancements make it possible to precisely determine specific biological and functional attributes of whey protein ingredients. Their characteristics such as foaming, gelation, and emulsification or the potential role they play in areas such as blood pressure control can help increase the value of a variety of foods. Several prototype formulations which demonstrate this value are available from Davisco, 11000 W. 78th St., Ste. 210, Eden Prairie, Mn 55344 (phone 952-914-0400; fax 952-914-0887; www.leadingthewhey.com).

For example, a Mocha-Flavored Protein Beverage Mix may be formulated with a Bioactive Peptide System™ called BioZate 1. The clean-flavored whey protein isolate with bioactive peptides is suitable for nutritional applications such as this beverage, with each 30-g serving containing 20 g of the ingredient. Research has shown that it can significantly reduce blood pressure in hypertensive rats. Furthermore, a dose of 20 g of the ingredient appears to reduce both systolic and diastolic blood pressure in untreated borderline hypertensives.

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A Whey Protein Fortified Instant Oatmeal (Maple Brown Sugar) is made with Instantized BioZate 1, a protein that is readily dispersible and which contributes 10 g of protein per 52-g serving. It offers the same health benefits as the previous ingredient. A second cereal formulation, Whey Protein Fortified Instant Oatmeal (Vanilla Cinnamon) is formulated with Instantized BiPro®, a whey protein isolate which is readily dispersible; has a clean, bland flavor, and contributes 10 g of protein per 52-oz serving.

Whey Protein Chips (Parmesan Flavor) are fortified with BiPro®, a whey protein isolate which can help create a healthier snack. It contributes 10 g of protein per 28-g serving. Like its instantized form, it has a clean, bland flavor.

Whey Protein Breath Strip is formulated with BiPro whey protein isolate, which has excellent film-forming properties. These film-forming properties can be modified to achieve the desired finished product. Both soluble and insoluble films can be made with the ingredient, depending on the processing conditions. The clean, bland flavor of the ingredient is compatible with all flavor systems.

New Proteins from Down Under. A proprietary line of dairy ingredients, said to be manufactured in Australia under strict quality control conditions, has been introduced under the name Natra by Erie Foods International, Inc., 401 7th Ave., Erie, IL 61250 (phone 309-659-2233; fax 309-659-2822; www.eriefoods.com). The ingredients include milk and whey protein concentrates and isolates, casein, lactoferrin, colostrum, and milk calcium.

Studies have shown the health benefits of the two newest additions, lactoferrin and colostrum. Lactoferrin, which has the ability to build immunity and fight disease, may be used in infant formulas, health foods, supplements, and other products. Colostrum is rich in components which improve the immune system and gastrointestinal health, and can act as an antibacterial and antiviral agent.

The company’s brochure, Engineered Protein Solutions, discusses the multifunctionality of milk proteins and how they can be tailored to meet the specific needs of food formulators. Milk proteins exhibit capacity for emulsification, water binding, stabilization, heat stability, viscosity, solubility, body, and mouthfeel. These properties allow food products to be developed to reduce fat and cholesterol.

New Innovations in Soy and Whey Proteins. Several innovations based on proteins derived from soy, whey, or a combination of them have been introduced by Protient, Inc., 1751 W. Country Rd. B, Ste. 200, Saint Paul, MN 55113 (phone 651-638-2600; fax 651-697-0997; www.protient.com).

A water-filtered soy protein isolate called SPI 6200 has low viscosity and high dispersibility, making it suitable in beverage dry mix applications such as protein shakes. Because of its lower water-holding capacity, it may also be used in nutrition bar applications. Furthermore, according to the manufacturer, the ingredient has a bland flavor profile that is free of beany or bitter notes, allowing manufacturers to formulate without masking agents.

A whey protein hydrolysate, marketed under the name Prolong 90™, may be used as a bar-softening agent. It is said to deliver superior nutrition with minimal off-flavors and bitterness.

An extruded product combining two protein isolates, whey and soy, was recently launched. Called Crisp 50 Whey + Soy, it provides superior nutritional profile, appearance, texture, and taste for use in bars, snack mixes, confectionery, cereals, and general nutrition supplements.

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Whey Proteins Used to Make Crunchy Snack. Researchers at USDA’s Eastern Regional Research Center in Wyndmoor, Pa., recently filed a patent on a twin-screw extruder process which is making possible crunchy snacks formulated with whey proteins.

The researchers wanted to improve the nutritional profile of puffed snack foods by extruding corn flour with concentrated forms of whey. Most crunchy snacks are made from high-starch products such as corn flour. By using whey in the formulation, protein levels in expanded products such as breakfast cereals, corn puffs, cheese curls, and energy bars can be increased from the traditional average of about 2–5% to 35%.

At first, the researchers found that the use of whey protein isolate reduced the crunchiness, color, and texture of extruded snack foods. However, they were able to change the temperature and moisture in the extruder so that the whey protein isolate blended well with corn flour to make the snacks crunchier.

The new snacks could meet the needs of health-conscious consumers and the process used has reportedly, drawn the interest of food companies.

Proteins Function as Fat Replacers. Protein ingredients that retain flavor, juiciness, succulence, and texture in low-fat food products was recently unveiled by Flavex Protein Ingredients, a division of The Arnhem Group, 25 Commerce Dr., Cranford, NJ 07016 (phone 908-709-4045; fax 908-709-9221; www.flavexprotein.com). These ingredients are intended for inclusion in value-added meat, poultry, cheese, seafood, marinades, sauces, gravies, soups, and spice blends.

A protein-based ingredient, marketed under the name Aquagel, can function as a replacer for fat in meat products, baked goods, and confectionery products. The ingredient, made by a patent-pending process, is free of cholesterol and allergens.

“Current concerns about the health effects of trans-fatty acids and saturated fats in food systems should make Aquagel an important development for food processors and health-conscious consumers,” said a company representative.

A second development, Flavex 95™, allows food manufacturers to reduce the fat content in foods by substituting a fat-replacement product that is composed of protein and water. It is said to enhance flavor and texture while providing a fat mouthfeel. It can be injected in whole-muscle meat, poultry, or fish filets for better dispersion in brine solutions. The ingredient has been instantized to eliminate protein coagulation during the injection process.

In addition to providing a high protein contribution to food systems, the protein-based ingredients are said to offer a number of functionality characteristics, including high water-holding capacity, strong emulsification properties, a reverse gelation property in cold or heated systems, and the ability to mimic fat viscosity and act as a flavor carrier in low-fat formulations.

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Lactoferrin to Be Used as an Anti-microbial. Activated Lactoferrin as an antimicrobial will be marketed by aLF Ventures, a company formed by Farmland National Beef and DMV International. A naturally occurring protein found in milk, activated lactoferrin may be sprayed on to raw beef carcasses to inhibit the growth of Escherichia coli, Salmonella, and Campylobacter, to prevent them from attaching to meat surfaces.

The Food and Drug Administration informed aLF that it does not question the company’s decision to market activated lactoferrin as a component of an antimicrobial spray.

“Innovative technology is a critical building block in preserving the strong foundation of the U.S. food supply,” said Lester Crawford, FDA Deputy Commissioner. “We must continue to encourage scientific research and new technology to maintain this nation’s safe food supply.”

The company provided FDA with scientific data supporting the conclusion that activated lactoferrin is Generally Recognized As Safe and safe for the general population as well as individuals who are allergic to milk. Furthermore, in its notice submitted to FDA, the company noted that the amount of added lactoferrin that remains on the beef after spraying is comparable to the amount of lactoferrin that is naturally occurring in the beef.

aLF also submitted data to the US. Dept. of Agriculture regarding the effectiveness of lactoferrin as an antimicrobial.

For more information, write to aLF Ventures, LLC, 299 S. Main St., Salt Lake City, UT 84111 (phone 801-961-1131; fax 801-961-1135).

Protein-Containing Particulate Helps Low-Carb Development. A blend of soy protein isolate and calcium carbonate has been used to create a particulate that contains no net carbohydrates and no sugars. Called Zero Carb Crisp, the ingredient has been developed by Nuvex ingredients, Inc., P.O. Box 158, Blue Earth, MN 56013 (phone 507-526-4341; fax 507-526-2838).

The ingredient, which reportedly contains 80% soy protein, allows manufacturers to develop low-carb products such as energy bars and other suitable applications. For example, one prototype formulation using the inclusion was a Low Net Carb Lemon Yogurt Bar.

The company, a manufacturer of particulates and inclusions, also developed Proti-Oats, a rolled oat with 50% soy protein for use in energy bars, cereals, baked goods, and other products that contains rolled oats.

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Whey Ingredient May Provide Better zzz’s. A whey protein hydrolysate called Cysteine Peptide which may provide energy, motivation, and better sleep was recently launched by DMV International.

According to the company, as we age, the body produces less glutathione, which is needed to break down toxic substances, alcohol, and stimulants such as caffeine. Cysteine Peptide allows the body to synthesize glutathione. Alcohol and caffeine are known to disrupt sleep patterns. Through the production of glutathione in the liver, it helps break down these substances. “Helping the body to remove these substances supports restorative sleep, leaving consumers energized and full of vitality,” said a company representative.

Research studies were initially conducted with consumers older than 50 years. However, a followup study is planned for 2004.

More information about the potential health benefits of this ingredient can be obtained from DMV USA, 40196 State Hwy. 10, Delhi, NY 13753 (phone 607-746-0100; fax 607-746-2710; www.dmv-nternational.com).

Award-Winning Wheat Flour Has Freeze/Thaw Resistance. A wheat-based thickener called FCI TW1000® received FI Europe’s second-place award for “Most Innovative Food Ingredient 2003.” The texturant, a wheat flour with freeze-thaw resistance, was developed and recently launched in the European market by Limagrain Cereals Ingredients, ZAC Portes de Riom sud, Av. Georges, Guerschwin, 63200, Riom, France (phone +33-473671817; fax +33-473671799; www.lci.limagrain.com).

According to the company, the ingredient offers a variety of benefits, including strong viscosity and high blending power after cooking, thickening properties for creating texture, stability to shear, resistance to freeze-thaw cycling, and pasteurization properties. Derived from wheat, it may be used in bakery goods and other products, and can be labeled as a “wheat flour.”

Improving Soy Taste Through Flavor Modification. The Solae Co., a soy ingredient research, manufacturing, and marketing company formed by DuPont and Bunge Ltd. in 2003, has partnered with Cranbury, N.J.-based Linguagen Corp., specialists in flavor modification. The companies will work together to identify and develop flavor modifiers that will continue to improve the taste of soy protein to meet the needs of consumers. When their research goals are achieved, the companies may agree to commercialize these flavor-modifying compounds.

Product lines currently offered by The Solae Co., include soy protein isolates, soy concentrates, soy fibers, and soy lecithins, as well as the Solae™ ingredient brand.

One of the company’s interesting innovations is extruded soy nuggets in a range of densities, sizes, and protein levels. Its newest addition is a soy nugget containing 80% protein. The soy nuggets can add texture, crunch, and protein nutrition to a variety of applications, including food bars, cereals, snack mixes, and other products.

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A Protein Tooth? Everyone is probably familiar with the phrase, “having a sweet tooth.” It means, of course, having a craving for something sweet.” But how about the phrase, “having a protein tooth?” While the latter is not as well-known, or at least as well-defined, its meaning may have increasing significance in the formulation of foods and the creation of new ingredients.

A “protein tooth” refers to a craving for amino acids, which are found in proteins. “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.

There are two main categories of umami substances: Amino acids such as monosodium glutamate (MSG) 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. These substances are synergistic—when used in combination, their taste is amplified.

According to researchers, this synergism creates a desirable taste which helps motivate the individual to eat a balanced diet, and in particular, consume health-promoting essential amino acids. Umami substances in aged meats and fish help make vegetables taste better. The glutamate in tomato-based pasta sauces combines well with the protein in meatballs, carbohydrates in the pasta, and the sprinkle of aged cheese.

Researchers are looking more and more at this area of taste. For instance, work has been done on identifying a new receptor on the tongue which is most sensitive to glutamate. Researchers are also looking at how the brain determines the final taste of an amino acid.

More information about research studies can be obtained from Sokol & Co., 5315 Dansher Rd., Countryside, IL 60525 (phone 800-328-7656; fax 708-482-9750; www.solofoods.com). The company manufactures a variety of ingredients that impart a umami taste. For example, it recently introduced Certified Savory™ Southeast Asian fish sauce, an essential ingredient in Thai and Vietamese dipping sauce applications. Fish sauce is said to provide a superior umami functionality in Asian marinades and entrees, while improving the browning characteristics of grilled and stir-fried foods.

Highlights from Protein Portfolio. Protein ingredients, which include milk and casein proteins, whey protein concentrates and isolates, and bioactive milk protein fractions, are available in a “protein portfolio” from Glanbia, 526 6th St., Monroe, WI 53566 (phone 608-329-2800; fax 608-329-2828; www.glanbianutritionals.com).

The following are some of the newest developments from the portfolio:
• A whey protein isolate—called Barflex—was specifically designed for extending shelf life of nutrition bars. The addition of the ingredient as a sole protein or as part of a blend can significantly improve the texture of the bar, allowing increased shelf stability and improved consumer acceptability.

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• A bioactive whey fraction, marketed under the name Salibra™ 700, is produced using a special selective membrane transfer system. It contains a number of components that can promote a healthy intestine as well as provide support to the immune system. In addition to its high concentration of bioactive components, it offers a variety of useful functionality properties, including emulsification, thickening, water binding, and texture stabilization.

• A whey protein isolate called Provon is said to be suitable for nutritional applications requiring excellent amino acid profiles, high solubility, and clean taste. Available in spray-dried and instant forms, it may be used in such applications as cookies, snack mixes, ready-to-eat cereals, protein bars, protein beverages, and other products.

Eggs Play a Role in High-Protein Diets. “Formulating High-Protein Foods” is the title of an article in The EggsAminer (Fall 2003), a quarterly newsletter for food manufacturers from the American Egg Board, 1460 Renaissance Dr., Park Ridge, IL 60068 (phone 847-296-7043; fax 847-296-7007; www.aeb.org).

Naturally high in protein (one large egg contains 6.25 g) and virtually carbohydrate-free, egg products can assist in the formulation of high-protein, low-carbohydrate foods. “Egg products are a tool to help boost protein levels in prepared foods—adding nutritional value to the food,” noted the article, which included several studies on the value of proteins in weight-loss diets.

In addition to being a high-quality source of protein, egg products can provide solutions to common challenges in food product development. In a new publication, Egg-Ceptional Innovations Application Guide, information is available about the functionality properties of eggs. Also provided are basic formula recipes, easily adaptable to specific product formulations and organized by recipe types including appetizers, main dishes, sauces, and desserts.

Rice-Based Ingredient Offers 70% Protein. A rice protein concentrate containing a minimum of 70% rice protein is available from A&B Ingredients, 24 Spielman Rd., Fairfield, NJ 07004 (phone 973-227-1390; fax 973-227-0172; www.abingredients.com). Called Remypro N70+, the ingredient has an amino acid profile similar to that of mother’s milk, is easy to digest, and will not cause allergic reactions.

Several years in development, the rice-derived ingredient is said to offer improved flavor, consistent color, reduced grittiness, and superior quality. It can add nutrition value to a variety of products, including energy bars, meal replacement systems, nutritional supplements, extruded products, and baked goods.

Producer of Soy Protein Products Changes Name. A major producer of soy-based textured vegetable protein products has changed its name from PMS Foods LP to Legacy Foods LLC. The company offers a wide range of protein products in flavored and unflavored versions.

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According to the manufacturer, an unflavored textured soy protein, marketed under the name Ultra-Soy®, may be used as a meat extender or replacer in pizza toppings, stews, and a variety of other products. A flavored soy-based analog, part of the Imagic® line, is designed to simulate the texture of meat such as bacon, chicken, or beef bits.

For more information, write to Legacy Foods LLC, P.O. Box 1099, Hutchinson, KS 67504-1099 (phone 620-663-5711; fax 620-663-7195).

Organic Soybean Powder Offers Microfine Particle Size. An organic power made from whole soybeans was introduced at FI Europe 2003 by Archer Daniels Midland Co., 4666 Faries Pkwy., Decatur, IL 62526 (phone 217-424-5424; fax 217-424-5580; www.admworld.com). Called NutriSoy® Whole Bean Powder, the product has a microfine particle size, but is manufactured to retain proteins and other key components of natural de-hulled whole beans.

According to the manufacturer, the ingredient offers a smooth, rich mouthfeel and a good flavor profile—characteristics which make it suitable for use in the formulation of soy beverages, frozen desserts, and fermented soy products without compromising taste. It can blend with any flavor system and adapts easily to existing processing methods.

Whey Protein Concentrates Offer Improved Functionality. Customized whey protein concentrates offering improved functionality were recently launched by Foremost Farms USA, P.O. Box 111, Baraboo, WI 53913-0111 (phone 608-355-8769; fax 608-355-8695).

Whey protein concentrates containing 34% protein have been modified to give stronger gelling properties than their traditional counterparts. This enhanced functionality helps bind water and prevent moisture loss upon cooking in processed meat applications. Also, a heat-stable whey protein concentrate has been specifically customized to make it suitable for retort and aseptic applications. This ingredient is said to provide good solubility under high heating conditions and can help enhance mouthfeel or texture while providing nutritional benefits. Such developments are a good illustration of the impact that advancements in technology are having in improving the functionality of proteins and customizing them for specific applications.

Milk Protein Isolate Offers Functional Properties. A natural milk protein isolate containing all the protein fractions found in milk is available from American Casein Co., 109 Elbow Lane, Burlington, NJ 08016-4123 (phone 609-387-3130; fax 609-387-7204; www.americancasein.com).

Called CMP-221, the product is said to have a milk-like flavor, a high protein efficiency ratio, excellent solubility, low-fat content, and low lactose content. It is suitable for use in low-fat applications, nutritional supplements, and other powdered or extruded products.

According to a company representative, demand for milk protein isolate has significantly increased in recent months. “We manufacture milk protein isolate through a spray drying process which promotes a clean, milk-like flavor, good dispersibility, and excellent solubility and functional properties. This high-protein ingredient is generally used to manufacture health and nutritional products.”

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Preparation of a Stable Acidic Milk-Based Beverage. A process for preparing a stable acidic milk-based beverage which does not precipitate over time was the subject of U.S. patent 6,652,896, assigned to Nuvim Inc., Paramus, N.J. The product contains about 0.5-5.0% milk proteins and 0.1–2.0% of a food stabilizer and a food acid sufficient to lower the pH below 4.5.

When formulating a flavored drink containing milk proteins at a low pH of 3.5–4.5, whey proteins are generally favored because they are soluble under acidic conditions. Acidic flavored drinks with casein proteins are known to be unstable and produce large amounts of casein precipitate. The patent discusses a process and formulation for flavored low-pH milk-protein-containing beverages, which provide for significantly improved stability of the casein proteins with 97–99% stability.

Dried Gluten in Baking Reviewed. A new review on the use of dried gluten in baking, especially in breadmaking, is available from CCFRA Technology Ltd., Chipping Campden, Glos., GL55 6LD United Kingdom (phone +44 (0) 1386 842000; fax +44 (0) 1386 842100). The review, “Dried Gluten in Baking (CCFRA Review No. 39),” is a collection of articles and reports based on research carried out at the former Flour Milling & Baking Research Association, that were republished as a single compilation for maximum ease of use by the reader.

The development of a gluten structure is critical to the formation of a cellular structure in many baked products, especially bread, and is critical to end-product texture. Gluten is formed when the proteins in wheat flour are hydrated and subjected to the energy of mixing. In wheat flour, the level of proteins for gluten formation varies depending on many factors, while the amount required depends on the breadmaking process in use and the addition of other functional ingredients. Dried gluten has become a common supplement to flours for breadmaking, to achieve the desired level.

The review covers the addition of dried gluten to weak flours, the response of single wheat flours to gluten fortification, gluten fortification of brown flours, studies on commercial glutens and their baking quality, loaf volume improvement from gluten addition to flour, and the storage stability of gluten-fortified white breadmaking flours.

New Whey Protein Isolate Introduced. Whey protein isolate, produced through a special demineralization and microfiltration process that is devoid of heat, chemical, or enzymatic treatment, has been introduced under the name Prolacta WPI 90, by Lactalis Industrie USA, Inc., 2376 S. Park Ave., Buffalo, NY 14220 (phone 888-522-82547; fax 716-827-9728; www.liusa.com).

According to the manufacturer, the special process is said to preserve the natural quality and bioactivity of the milk proteins. The mixture of non-denatured proteins has a balanced amino acid content (high tryptophan/low threonine) that is said to be superior to that of other whey protein isolates. Containing 90% protein, the soluble milk protein powder is free flowing, cream colored, and clean flavored.

The ingredient can impart a number of important functionality properties to the application. For example, in dairy products it provides good moisture retention and emulsification, and is a highly concentrated source of bioavailable dairy protein. In breads and baked goods it helps moisture retention, adhesion, and emulsification. In confections it provides superior emulsification, thickening and gelling, and excellent whipping properties.

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Organic Soy Protein Isolate Introduced. An organic soy protein isolate called Isopro® was recently introduced by Spectrum Foods Inc., P.O. Box 3483, Springfield, IL 62703 (phone 217-391-0091; fax 217-391-0096; www.nexsoy.com). Because of its bland flavor and excellent solubility, the ingredient is said to be suitable for liquid and dry beverage applications, supplements, nutrition bars, meat analogs, and extruded and baked products.

Prior to this development, the company unveiled a solvent-free line of certified non-GMO and organic soy ingredients marketed under the Nexsoy® brand name. The processing method used is entirely mechanical, eliminating traditional chemical processing with solvents such as hexane.

Soy Protein Isolates Provide Neutral Flavor. A new line of soy protein isolates reportedly having a neutral flavor is available from Cargill Soy Protein Solutions, 15407 McGinty Rd., W. MS 46, Wayzata, MN 55391-2399 (phone 800-769-7768; fax 952-742-6879; www.cargillsoyprotein.com). Launched under the name Prolisse, the ingredient is said to exhibit superior solubility compared to other isolates, and impart a smooth mouthfeel.

According to the manufacturer, the isolate provides a number of functionality benefits, including water holding, emulsification, and gelling, which help to maintain or improve food quality. It works well in a number of foods and beverages, including dairy-like products, infant formulas, processed meat and poultry, meat alternatives, baked goods, and other prepared foods.

Furthermore, the expanding line of ingredients enables the company to meet the varying application needs of specific products. For example, a high-viscosity, high-gelling isolate can be formulated to produce excellent meat substitutes that have a meat-like texture. Or a low-viscosity, highly soluble isolate could be effective in the creation of a ready-to-drink nutritional beverage.

Whey Fraction Has High Concentration of Alpha-Lactalbumin. A method of processing whey to obtain a filtrate or precipitate having a high concentration of alpha-lactalbumin is described in U.S. patent 6,613,377, assigned to AMPC, Ames, Iowa. The method involves the addition of an acid during processing to lower the pH of the whey to less than 4.0, with a preferred pH range being from 3.3 to 3.8. The pH adjustments result in an enriched alpha-lactalbumin fraction after further processing. This pH adjustment process may be accommodated to membrane filtration and precipitation methods.

According to the patent, the inventor has determined that adjusting the pH of the whey to a more acidic level during processing causes a change in protein conformation and improved retention of the alpha-lactalbumin during later processing. This change in conformation and improved retention provides a high concentration of alpha-lactalbumin in the protein fraction without the need for heat processing or other expensive separation processes.

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Soy Powders Have Neutral Flavor Profiles. High-protein soy powders having the functionality of traditional soy isolates with a superior flavor profile are available from Nutriant, 2712 Orchard Dr., Ste. A, Cedar Falls, IA 50613 (phone 319-277-3250; fax 319-266-1703; www.nutriant.biz). Their flavor profile allows high inclusion rates in food and nutritional applications.

Marketed under the brand name Iso, they have strong emulsification properties with high viscosity characteristics and excellent solubility. They are available in different versions, depending on the applications and characteristics needed. For example, Iso II may be used in baked goods, protein bars, nutritional snacks, cereal products, and specialty breads. Iso III may be used in meat and dairy analogs, bar coatings, cheeses, meat products, and chocolate products.

Pea-Derived Ingredients Offer Protein. A pea protein isolate which offers a high level of functionality and nutrition is manufactured under the name Propulse™ by Parrheim Foods, 880 Phillips St., Portage la Prairie, Manitoba, Canada R1N 3B7 (phone 204-239-5995; fax 204-239-6007; www.parrheim.com). Containing 82% protein, the ingredient may be used in nutrition bars, meal replacement beverages, baby food formulations, vegetarian applications, pasta, meat and seafood products, breads, dressings, and other products where protein is required.

According to the manufacturer, the ingredient has a bland taste and can function as an alternative to soy protein. It offers an excellent means of protein fortification without significant alteration in color, flavor, or odor.

Also available is Propulse 975™, a pea protein fraction containing 75% protein. It offers a high level of functionality and an amino acid profile complementary to that of wheat flour and other cereal foods.

Fish-Derived Ingredient Offers Alternative Protein Source. A high-quality fish collagen hydrolysate designed to be used in applications where a protein from a non-mammal source is preferred is available from Protein Products, Inc., 76 Carlton Lane, North Andover, MA 01845 (phone 978-689-9083; fax 978-975-4325). Called Peptan F, it offers good solubility and flavor characteristics which are important for high-protein formulations such as nutrition bars and beverages.

Parrheim Foods is represented in the U.S. by Norben Co., Inc., P.O. Box 766, Willoughby, OH 44096 (phone 440-951-2715; fax 440-951-1366).

Whey Protein Isolate Contains Lactoferrin. An undenatured whey protein isolate naturally rich in biologically active lactoferrin was recently launched under the name Vitalarmor LFX 100 by Euro Proteins, Inc., 908 N. Dixie Hwy., Wapakoneta, OH 45895 (phone 419-738-4060; fax 419-738-4426; www.europroteins.com). Because it contains 1% lactoferrin, it reportedly offers cost benefits, convenience, and effectiveness over other whey protein isolates.

Obtained by ion exchange through a positively charged resin, the ingredient can strengthen the body resistance by stimulating the immune system, modulating the anti-inflammatory response, and fighting free radicals.

In addition, the company has developed milk protein fractions called Try-Pro which can enhance serotonin levels in the brain. Low serotonin activity can be responsible for sleep and mood disorders, premenstrual syndrome, eating disorders, and anxiety and depression related disorders.

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Whey Protein Manufacturer Acquired. Whey protein isolates, marketed under the Isolac line, are available from Century Foods International, P.O. Box 257, Sparta, WI 54656 (phone 608-269-1900; fax 608-269-1910; www.centuryfoods.com). The homogeneous, free-flowing whey protein isolate powders are made using a microfiltration/ultrafiltration process to concentrate the protein fractions and then spray-dried for use in a variety of food and beverage systems. Also included in the line is an instantized version and a version for use in beverages where clarity is important.

In July 2003, Hormel Foods Corp. acquired the company, a major supplier of ingredients for ready-to-drink protein beverages and nutrition bars. The acquisition will further enhance the position of Hormel in the growing specialty foods segment.

Isolates Contain Less Denatured Proteins. Whey protein isolates manufactured with a low-temperature microfiltration process for less-denatured proteins and excellent functionality benefits are available from Proliant, Inc., 2325 N. Loop Dr., Ames, IA 50010 (phone 515-296-7100; fax 515-296-7110; www.proliantinc.com). Marketed under the name Iso-Chill™, the whey protein isolates typically provide 0–3% denatured proteins, while other whey processing technologies utilize higher temperatures that may cause up to 15% denatured proteins.

Since these isolates carry a low percentage of denatured protein, nutritional products can have a full balance of bioactive whey protein fractions, including immunoglobulin, lactoferrin, and glycomacropeptides. They also provide a variety of functionality benefits, such as clean, bland flavor; white color; high solubility and clarity, and acid and heat stable properties.

Recently the company formed a joint venture with Trega Foods, a manufacturer of cheese and dairy-based ingredients, for the production, sales, and marketing of whey protein isolates. The venture is said to strategically unite Proliant’s sales, marketing, research and development, and application research with Trega’s state-of-the-art manufacturing capabilities.

Line of Protein Ingredients Expanding. High-protein meat stocks in dried or frozen form are available from Hormel Specialty Products, 1 Hormel Place, Austin, MN 55912-3680 (phone 800-956-0399; fax 507-437-5120; www.hormel-spd.com). Marketed under the name Great Beginnings, the water-soluble meat stocks are derived from slowly cooking bones, muscle, and meat to extract flavors and aromas important to the application, and flash sterilized. The line features a complete range of flavors, including beef, pork, meat, ham, turkey, and chicken. Also available is the Building Blocks® line of free-flowing powders and concentrated pastes available in beef, pork, chicken, or ham flavors. Applications for these ingredients include soups, sauces, gravies, meat pot pies, dry mix seasonings, stews, and frozen entrees.

Recently, the company has expanded its line of Coretrate® gelatin dessert concentrates to include flavors for the younger market. Included in this line are sour flavors—cherry, green apple, lemon, grape, and berry—and soda flavors—cherry cola, root beer, and citrus lime.

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Nuts Offer Source of Protein. In July 2003, the Food and Drug Administration approved a qualified health claim that states, “Scientific evidence suggests, but does not prove that eating 1.5 ounces per day of most nuts, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease.” Among the healthy components of nuts are, of course, protein.

Interestingly, as pointed out in The Nutraceuticals & Functional Foods section of the January 2004 issue of Food Technology, almonds and soy proteins were among the foods included in an eating plan that was designed to be a heart-healthy, low-saturated-fat diet. More information on the results of this study can be found in the section, which discussed the role that nuts (almonds, hazelnuts, pecans, pistachios, walnuts, and peanuts) can play in lowering cholesterol, aiding weight loss, and improving cardiovascular health.

As an ingredient, nuts offer a source of protein while providing such functionality characteristics as flavor, texture, and color. Furthermore, they may be used in a variety of applications ranging from frozen desserts to baked goods to culinary dishes.

Soy Protein Isolate Has Special Gelling and Emulsifying Properties. A new soy protein isolate for infant formula, nutritional foods and beverages, and emulsified meat and poultry products is available from Solbar Industries, Ltd., P.O. Box 2230, Ashdod 77121, Israel (phone 972-8-8632111; fax 972-8-8561455; www.solbar.com). Containing a minimum of 90% protein, the ingredient is highly soluble and specially designed to emphasize the naturally occurring gelling and emulsifying properties of soy proteins. It is also available in a vitamin-fortified formula.

In addition to this new development, other ingredients manufactured by the company include soy protein concentrates (Solcon S), textured soy concentrates (Contex) in a range of sizes and shapes, textured soy flours (Soytex), a steam-textured soy protein for instant soups and convenience meals (Bontex), and soy isoflavones (Solgen and Nutragen).

Hydrolyzed Gelatin Provides Rapid Dissolution. Latest addition to a family of hydrolyzed gelatin products was recently unveiled by Rousselot Inc., P.O. Box 0234, Waukesha, WI 53187-0234 (phone 888-455-3556; fax 262-650-8456; www.rousselot.com). Rousselot™ Hydrolyzed Gelatin APC is manufactured in France from Type A Gelatin. The ingredient is said to be tasteless and odorless, and has unusual clarity.

According to the manufacturer, the gelatin product is agglomerated to provide rapid dispersal and dissolution even in cold water. Suggested applications include sports drinks for increasing viscosity and added protein, nutrition bars for both binding and added protein, and as a binder for tableting operations.

Protein Ingredients Include Gelatins and Collagen Hydrolysates. A range of protein ingredients, including gelatins and collagen hydrolysates, is available from P.B. Leiner, 366 N. Broadway, Ste. 307, Jericho, NY 11753 (phone 516-822-4040; fax 516-822-4044; www.gelatin.com).

Cold-soluble gelatins, marketed under the name Cryogel® and Instagel®, do not require heat to dissolve or activate the gelatin. The gelatins, which are said to have excellent flavor release and desirable mouthfeel, are suitable for dessert, mousse, and other dairy applications.

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Collagen hydrolysates, called Solugel® and Polypro®, are available in cold-soluble spray-dried powder or clear amber liquid. They are well suited to the development and formulation of protein beverages and energy bars. Multifunctional, they provide a source of high-quality protein in addition to providing a soft texture and extending the shelf life of nutrition bars.

Years ago, when you thought of proteins, most likely a juicy steak or hamburger would have come to mind. In any case, whey, a by-product or waste material, probably would not have been one of the first ingredients that a formulator would have thought of. The fact that many of the proteins discussed in this article are derived from whey only shows the evolving nature of ingredients in general. Also, other sources, such as soy and certain grains (for example, rice and canola), are presenting additional alternatives for the food formulator in this first decade of the new century.

The applications of proteins are also broadening. At one time, a protein shake found in a health store would have been one possibility. Today, as suggested by this article, uses might include any of the following: crunchy snacks, mocha-flavored drinks that help lower blood pressure, softening agents for nutritional bars, film formers for breath strips, fat replacers, low-carbohydrate foods, gelatin desserts, flavor-enhancing substances, and even antimicrobials.

Many of these applications are being made possible by technologies which are creating new ingredients that offer improved functionality or health benefits. This article has covered microfine soy powders that retain their proteins and other key components, whey protein concentrates that have been modified to give stronger gelling properties, a new cheese-making process which can capture valuable proteins, an extraction process to separate protein from fiber in canola meal, new and improved fractionation methods, modified extruder processes to create snacks made with whey, demineralization and microfiltration processes that are devoid of heat, chemical, or enzymatic treatment, and many others which are developing increasingly customized ingredients for specific applications.

Another reason for the broadening applications is proteins’ ability to work with other ingredients. This article discussed, for example, an inclusion containing soy protein and calcium; a gelatin replacer containing an emulsifier, vegetable fat, and milk protein; an extruded product combining whey and soy proteins; gelatins containing innovative flavors; and many others.

Also playing a factor are a number of tests available which help determine protein quality. Although I haven’t really discussed them in this article, they might include protein efficiency ratio, amino acid scoring, and protein digestibility corrected amino acid scoring. The important point here is that improved testing is taking into consideration both the amino acid content and bioavailability.

What does this all add up to?

Based on the developments in this article, I think we can see that the evolving nature of proteins, in particular, their functionality and health characteristics, will play an important role in future formulating and reformulating of foods and beverages. Since next month’s Ingredients section will be discussing ingredients for low-carbohydrate foods, this will probably be a good place to stop this month’s conversation.

Suffice it to say, although “groovy” may be an antiquated term describing the “Age of Proteins,” there’s nothing outdated about proteins and their new developments.

Next month’s Ingredients section will look at the variety of ingredients or “tools” available to the formulator when developing products that fit the low-carbohydrate trend.

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

About the Author

Food Technology magazine Senior Editor and key member of the Food Technology editorial staff for 26 years.
Donald Pszczola