Sessions on Processing Present New Concepts

Each year, the IFT Annual Meeting Technical Program features an assortment of forums, symposia, and oral and poster sessions on a wide variety of topics concerning ingredients, processing, and technologies. The quality has steadily improved over the years as the organizers have become more selective, even as the number of presentations has grown.

The sessions on processing and engineering are often the first place where new concepts are presented, such as high-pressure processing and pulsed electric fields in past years. Now the underlying mechanisms for these novel techniques are being discovered and the processes are moving into commercial practice. Scanning the topics of sessions and papers this year gives a sense of new interests and trends which foretell future advances.

Power ultrasound is a versatile technique in food processing, according to the papers in session 101 on Wednesday afternoon. Among the interesting applications are the formation of protein microspheres, the inactivation of enzymes, peeling of tomatoes, enhancement of heat and mass transfer, and protein starch separations.

Microbes can apparently communicate with each other in ways that can be exploited for food preservation, according to the papers in session 42 on "Control of Quorum Sensing Signals" on Monday afternoon. Foodborne microbes seem to require a threshold number before expressing chemicals that lead to food deterioration, such as enzymes and toxins. They sense the presence of their fellow organisms through specific chemicals. Experiments have shown that other chemicals can inhibit the reception of the signals, thus reducing the expression of harmful effects. Experiments have been performed on bean sprouts, where microbes can cause a form of rot, and in milk, where other microbes cause clotting. The early speculation is that further research will show opportunities to use a form of biological control to improve shelf life of foods.

The New Products & Technologies Committee is presenting three sessions (2, 21, and 56) on Sunday afternoon, Monday morning, and Tuesday morning, featuring commercial innovations in nutritional ingredients and processing; functional ingredients; and analytical innovations, respectively. This committee uses its industrial and academic experts to screen about 50 submissions each year, accepting fewer than half for presentation. Subjects must be recently commercialized and demonstrate distinctive novelty and utility.

Session 26 on "Food Defense and Protection: Detection of Poisonous Agents" on Monday morning is surprisingly the only session explicitly focused on this topic, but it is safe to predict that future meetings will have more discussion. Both broad assessment of vulnerabilities and specific detection of toxins will be presented. Research on protection against food bioterrorism will have applications in preventing other food safety incidents. One of the more-promising concepts, hinted at in this session, is that of a broad sensor for toxicity, as distinct from sensors targeted at specific toxins, such as botulinum.

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In addition to several interesting papers on particles, microwave heating, and modeling, session 52 on Monday afternoon will feature the Food Engineering Division lecture by Enrique Rotstein of General Mills on "Engineering Innovation in the Food Industry," followed by the a wine and cheese reception, a charming event initiated in 2004. Rotstein has been personally responsible for a number of innovations at Pillsbury and now at General Mills, after an academic career in Argentina.

One might expect more attention to be paid to irradiation, but there is only one session on this topic, session 58, "Advances in Food Irradiation Technology," on Tuesday morning. Several of the papers deal with aspects of electron beam processing, drawing on the facility at Texas A&M University. Electron beams have the advantage of being capable of being turned on and off rather than having to cope with a radioactive isotope. On the other hand, they have reduced penetration compared to the gamma rays emitted by the isotopes. The major manufacturer of electron beam machines has gone out of business, but one has to believe that others will enter the business.

Calorimetry as a tool for food process design is the topic of session 74 on Tuesday afternoon. Papers describe research on roasting peanuts, meat proteins, and foodborne microbes using differential scanning calorimetry. DSC is a powerful tool for sensing phase changes and other exothermic or endothermic transitions in small samples.

On the less-glamorous but critical side is session 93, "Integrating Preventive Maintenance into HACCP," on Wednesday morning. This continues the attention paid by food engineers to maintenance at the 2004 IFT Annual Meeting.

Session 63, "Nondestructive Food Testing: Innovation and Novelties," on Tuesday morning discusses nuclear magnetic resonance, Raman spectroscopy, microwave absorption, electronic noses, and ultrasound as testing techniques for foods. There is also an explanation of the use of reference methods for calibration of such tests.

As always, there are numerous poster sessions sponsored by the most divisions, but an especially interesting one is session 99C, "Mass Transfer and Electric Field Treatments," on Wednesday morning. Among other topics, there are posters on radiofrequency, ohmic heating, microwave/vacuum drying, and osmotic drying.

Nonthermal processing techniques are discussed in several sessions: session 9, "Mechanisms and Modeling of Bacterial Spore Inactivation by the High Pressure Processing," on Sunday afternoon; sessions 34 and 86, general nonthermal processing oral sessions on Monday morning and Tuesday afternoon; and sessions 54F and 99E, general nonthermal processing poster sessions on Monday afternoon and Wednesday morning. The nonthermal processing techniques discussed include high pressure, pulsed electric fields, irradiation, ultraviolet radiation, microwave pasteurization, ultrasound, and high-pressure carbon dioxide. Important topics include understanding the mechanisms of microbial inactivation and validating these novel processes, especially for low-acid foods.

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Session 62, "Intervention Strategies for Fresh Produce," on Tuesday morning includes, among others, an interesting discussion on use of biological control instead of chlorine on sprouts.

Session 105 on Wednesday afternoon asks, "Organic Foods Are Huge in Retail: Why Not in Foodservice?" The papers discuss the unique challenges of the foodservice channel, including how organic foods can be processed appropriately.

While membrane processing is well established, some specific applications are still noteworthy, as exemplified by session 16, "UF Milk and UF Milk Ingredients in Food Products," on Sunday afternoon. As the lead paper by B.D. Blanchard of GEA Filtration says, while ultrafiltration of milk has been widely applied around the world for many years, production of ultrafiltered milk in the North American marketplace was largely limited due to fiscal constraints associated with milk support price levels in this market. In recent years, however, combinations of factors have converged, making domestic production of milk protein concentrates both common and commercially attractive. Other papers in the session discuss applications of ultrafiltered milk ingredients.

Session 90, "Biotechnology in the Seafood Industry," on Wednesday morning discusses the use of biotechnology techniques, such as PCR and DNA-based tests, for species identification and pathogen testing. The final paper addresses transgenic fish, of which there are already examples as commercial ornamental fish. Environmental concerns about releasing transgenic fish into the sea will probably be addressed by incorporating transgenic sterility.

On the nontechnical front, session 11, "Prismatic Views of Grantsmanship and Federal Funding Opportunities," on Sunday afternoon provides inside information from granting agencies such as the National Science Foundation and the U.S. Dept. of Agriculture, as well as perspectives by administrators and faculty members.

Rheology is so interesting and important to food processing that it has an entire poster session, session 36D on Monday morning, devoted to it. Topics include extrusion, mixing, the effect of gums on rheology, and the use of various instruments to measure textural and flow properties.

Session 71C, a general food engineering poster session on Tuesday morning, includes several interesting papers, especially one describing the use of bioluminescence in modified bacteria to detect the toxins of harmful algae blooms. Other topics covered include extrusion, coating, and emulsions.

Session 71D, a parallel poster session on heat transfer, also on Tuesday morning, includes presentations on frying, freezing, thermal inactivation, and the effect of heating on texture.

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"The Many Faces of Fermentation Technology" will be discussed in session 78 on Tuesday afternoon. Wine, safety of bioreactors, malt fermentation, and bioregenerative waste utilization in the NASA space food system are among the topics that will be presented.

Session 25, "Enhancing Product Development Success by Combining Food Science and Culinary Arts," on Monday morning will continue a trend illustrated by the Culinary Challenge at last year's Food Expo. The papers recognize the increasing interest among chefs to know more food science and among food scientists to know more culinary arts.

If there are trends to be detected from this sample of papers and sessions being offered at the Annual Meeting, they may be in the topics just starting to appear, such as power ultrasound and toxin detection. Another observation is that processes that were obscure novelties just a few years ago are now widely studied and may be starting to reach commercial acceptance. Examples of these would be pulsed electric field, high pressure, and ultraviolet radiation. Irradiation by electron beam is being studied, but may be inhibited by the lack of a source for equipment. Ultrafiltration is a relatively older technology, but its application in this country for milk has been encouraged by regulatory changes rather than technical advances. Processing and engineering research on foods continues to produce exciting innovations.

EXHIBITS
Here are descriptions of some of the processing-related exhibits.

• Processing and product development are provided in Saskatchewan, Canada. Once an innovative idea has been researched at the University of Saskatchewan and the Saskatoon Research Centre of Agriculture and Agri-Food Canada, processing options range from a small-scale toll processing facility, the POS Pilot Plant specializing in process and product development, to the Innovation Place Bio Processing Centre, which provides toll or custom processing on a large-contract basis for the agri-food, nutraceutical, and cosmetic industries. The Saskatchewan Food Industry Development Centre's state-of-the-art, inspected, and organic-certified processing plant can provide unique processing opportunities and unprecedented market access. Solutions in commercializing a new venture are provided by Ag-West Bio, working for partnerships and industry growth through investments, aiding strategic alliances, providing regulatory advice, and opportunities for networking and communications. Ag-West Bio Inc., www.agwest.sk.ca/solutions, Booth 5317.

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• Miniature processing systems allow for scaling-up and scaling-down of aseptic, pasteurization, hot-fill, and continuous cooking processes. The new PLC-controlled system offers extensive automatic controls, data logging, and a complete on-board manual. The systems produce production-quality samples of such products as milk, shakes, soy milk, juices, puddings, baby foods, and more right in the laboratory. The processors are heat sterilizable and have flow rates of 300–4,000 mL/min. They are available with electric hot water or steam heat, steam injection, in-line homogenizers, tube or plate heat exchangers, vacuum cooling, multiple hold tubes, ultra-clean filling, and more. Miniature Plant Trial Services offer custom UHT and HTST processing. MicroThermics, Inc., www.microthermics.com, Booth 3327.

• Beverage systems include a hot-fill unit for UHT or HTST processing with a bottle-filling station (0.5–2 L/min), a self-contained batch bottle chiller, and a batch bottle pasteurizer. All systems can be custom designed to specification and are offered as skid-mounted, movable units. Bottom Line Technologies, Inc., www.blt-inc.com, Booth 859.

• Vacuum belt dryers conserve aroma and flavor and can be operated under freeze-drying vacuum. The heat to remove the humidity is transferred by thermal conductivity instead of radiation and is said to be 100 times faster than conventional freeze drying. The Zeodration process uses 4A Zeolite instead of an ice condenser to remove the water. The water is captured by the pores of the zeolite, but the pores are too small to fix the flavor molecules, which stay with the product. Brochures about batch cabinet vacuum drying and continuous drying in the vacuum belt dryer with the use of the Zeodration process will be available at the booth. Bucher Foodtech Ltd., www.bucherfoodtech.com, Booth 1066.

• Rotary valve for pneumatic conveying of bulk solids in the food industry offers quick and complete cleaning. The ZRD valve's FXS technology gives full access to all internal parts. The side plates of the housing can be swung together with the extracted rotor to the side to reach all internal parts without hindrance. The valve can be combined with the Fluidsplit® pneumatic conveying system, which is characterized by a very low transportation velocity and very gentle particle treatment. Also available are the new FCB gravity powder blender, which blends and homogenizes even cohesive bulk materials just by gravity flow out of a bin, and the Bulk-X-Change® bulk material heat exchanger for heating or cooling free-flowing powders and granules by gravity flow through a bundle of pipes. Coperion Corp., www.coperion.com, Booth 519.

• Twin-screw extruder, the Evolum HT 53, offers increased torque and screw speed, which in validation trials have been shown to provide 2–4 times the throughput of similarly sized twin-screw extruders while achieving equal or better product quality. The new extruder (53-mm screw diameter) can pump 200–2,000 kg/hr, compared 50–500 kg/hr provided by the BC 45 extruder (55.5-mm screw diameter). The total barrel length may range from 3 to 12 modules (L/D from 12 to 48), depending on processing requirements. A simple clamp system unlocks the barrel from the lantern to allow immediate barrel access for reconfiguration or dismantling. Clextral Inc., www.clextralgroup.com, Booth 2158.

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• Pilot-scale HTST/UHT system, the FT94, processes 50–100 L/hr and is designed for operation as a stand-alone unit or integrated into a full processing system with the capability of aseptic packaging of processed product. The new system offers two heat exchanger options, plate and concentric tubular types. The plate heat exchanger incorporates the latest plate profile technology, and the tubular heat exchanger is designed to operate with a wide range of food viscosities. The product is preheated by a steam-heated water circuit to prevent heat shock. Product main heating is by steam through the heat exchanger surface. Both product preheat and heating temperatures are automatically controlled, and set points are defined by the user. The FT94 incorporates full CIP and SIP functions. Armfield Ltd., www.armfield.co.uk, Booth 3811.

• Walk-through boot washer prevents meat plant employees from tracking pathogens from one part of a plant to another on the soles and sides of their boots. When a person walks through the sanitizing unit, fresh sanitizing solution is sprayed onto the boots. The system automatically begins spraying the solution as soon as the person enters the unit and stops immediately after he or she leaves, minimizing sanitizer waste and employee bottlenecks. Operators can adjust the nozzles for maximum boot coverage. The boot sprayer is approved for HACCP plans and requires only a standard 115-V, 5-amp electrical service to operate. Industrial Environmental Pollution Controls Corp., www.foamatic.com, Booth 4807.

• Twin-screw extruder, the BCTA, offers the combinations of high torques, screw speeds, and pressures that are essential to cover a wide range of applications. The high degree of modularity provides the optimal extruder configuration for the particular application. All critical zones are accessible for ease of cleaning, and the extruders can be easily incorporated into a process control system. The new BCTB control system allows users to select preprogrammed starting and stopping sequences. The control console can be freely swiveled and allows reliable monitoring of all machine functions. The control system regulates the feed of up to ten ingredients and can cool or heat up to ten barrel sections. The processing section is built from L/D basic modules up to 300 bar and 300°C, allowing an almost unlimited number of combinations and lengths. Buhler Inc., www.buhlergroup.com, Booth 2160.

• Instantaneous online measurement of moisture, oil, and flavorings is said to have advantages over conventional laboratory tests in terms of cost, time, representative measurements, and control. An article entitled "The Value of On-Line NIR Measurements in the Production of Snack Foods" discusses near-infrared measurement theory, instrument design, and the derivation of sensor readout, as well as NIR limitations, measurement accuracy, factors influencing accuracy, installation locations, and the practical use of the measurement at each location. The article will be available at the company's booth. Process Sensors Corp., www.processsensors.com, Booth 603.

by J. PETER CLARK
Contributing Editor
Consultant to the Process Industries Oak Park, Ill.
[email protected]