Industrial Applications of Selected JFS Articles

The current buzzword about food quality—wholesome—has so many meanings that it can be twisted around to describe whatever one wants it to mean. But safe food with at least its original nutrition, food that tastes and smells fresh, and food that doesn't cause disease is a minimum to fill the bill. That's what many of these papers are about: food that tastes good; food that provides nutrition, good flavor, and texture; food that is safe to eat. It takes a lot to keep foods in that category, whatever you wish to call it, and much of the work here represents the painstaking, step-by-step work of testing, understanding, and finding a better way to do what is necessary.

Argentine Studies Promote Understanding of Quality Loss in Frozen Foods

When frozen foods were first introduced, most of them were shrouded in ice crystals when they reached the consumer's kitchen. Most consumers called it “freezerburn” and either rinsed or chopped off the offending frost, or blamed the packaging supplier. Those early freezers were slow, and temperatures in the home freezer or refrigerator were much higher than today's appliances. Still, an understanding of exactly how that layer of frost develops provides a way to maximize quality, given the constraints of distribution. According to a group of Argentine researchers, the damage affects more than the food surface. It is understood that low freezing rates produce large ice crystals that damage tissues structure, which induces quality loss. Fast freezing generates more crystals of a smaller size. When unpackaged foods are frozen, the crystals sublime into the food surface, forming a dry, porous layer The thickness of the sublimated surface appears to be important to the final food quality, so the research team decided to develop an approximate prediction equation which would help calculate the size of the surface dehydrated layer as a function of food characteristics and freezing and storage condition. They also wanted to evaluate the size and structure of the dehydrated layer for different frozen meat samples stored during diverse time periods, and to validate the predictions from the developed equations against the experimental data obtained during their research. The research team found several important things that alter the perception of freezing as a process. For instance, they found that that phase change (sublimation) takes place on a defined moving front that divides the frozen and dehydrated regions, and not along a partially dehydrated zone. Using electron photomicrographs, they found that, as storage time extends, the size of the dehydrated layer increases continuously, with the correlated damage to the structure of the frozen food. Learning how different foods react to ice crystal formation should help food processors and packaging engineers to determine how much protection is required, and should help convince distribution systems operators to maintain temperatures along the chain. p E218-226.

High-Amylose Cornstarch Compared to Cholesterol

In a study by researchers from the Ehime Univ., Japan and Southwest Univ., Chongquing, China, the debate over how high amylose starch is digested and its affect on blood triglycerides and cholesterol continues. This study, titled “High-Amylose Cornstarch Decreases Plasma Triacylglycerol Concentration, but Not Plasma Cholesterol, in a Dose-Dependent Manner” found that high-amylose cornstarch decreases plasma triaglycerol concentration but not plasma cholesterol, in a dose-dependent manner. These researchers used ovarectomized rats in their studies; similar studies have been done with healthy humans. There has been controversy about the relationship between dietary fiber and high-amylose starches, and it appears that this agrument may not be settled yet. This group of researchers states that “a potential advantage of using HACS is the facility with which its content in food can be modified by choosing the appropriate raw materials and processing conditions.”

HACS, according to the authors, offers a major advantage because it can be technologically processed to alter the apparent DF content of foods without greatly changing their organoleptic properties. There is some debate over what constitutes high-amylose. In this study, the HACS was 68% amylose, compared to common starch at about 26%. The researchers found that plasma triacylglycerol concentration and apparent starch digestibility decreased as the dietary level of HACS increased: plasma cholesterol concentration, excretion of fecal bile acids, CYP7A1 activity, and liver lipids were not affected by the diets. However, the amount of propionic acid in the fecal content increased as the dietary level of HACS increased. HACS may lower lipogenesis in liver and adipose tissue and lower VLDL secretion by increasing propionic acid production, consequently leading to a decreased plasma triacylglycerol concentration. p S379-384.

Spices act as Antioxidants in Ground Beef

The effect of specific spices as antioxidants has been a favorite field of study for a number of researchers. In this paper, a group of researchers from Utah State Univ. have evaluated the effect of a popular East Indian spice blend on ground beef. Their paper, “Evaluation of Garam Masala Spices and Phosphates as Antioxidants in Cooked Ground Beef” studies the antioxidant effects and sensory attributes of individual ingredients (black pepper, caraway, cardamom, chili powder, cinnamon, cloves, coriander, cumin, fennel, ginger, nutmeg, salt, star anise) in an Indian spice blend (garam masala), as well as in the combination. For each spice treatment, the lowest effective spice level among those tested in this study (0.1, 0.5, or 1%) was defined as the lowest spice concentration that resulted in TBA values significantly lower than the controls (0% spice), or other spice levels. For black pepper, chili, coriander, cumin, fennel, ginger, nutmeg, and star anise, the lowest effective level was found to be 0.5%. Caraway and cardamom were found to have a lowest effective level of 1.0%. p C292-297.

Sweet Potato Pie is Only A Start

Most folks know that sweet potatoes are rich in antioxidants and fiber, and that we ought to eat them more often. But for those who just can't get motivated more than once a year to make that sweet potato casserole—you know the one, with the marshmallows—work reported in “Spray Drying of Amylase Hydrolyzed Sweetpotato Puree and Physicochemical Properties of Powder” by researchers from NC State Univ. and the USDA may lead to a wider use of this nutritious tuber as a food ingredient in all kinds of products.

They chose to tackle freeze drying of the vegetable puree, and founds ways around the viscosity of the paste and the concentration of sugars that leads to discoloration, big-time! By pretreating the puree with alpha-amylase and heating the puree, the viscosity of the sweet potato puree was reduced to a level that could be spray-dried, and by adding maltodextrin to the mix, the glass transition temperature was increased enough to reduce the stickiness of the spray-dried material, and to improve product recovery. Powder attributes were affected, but the RSM models appear to be permit production of specific color and moistures, particle size, and other characteristics in the final product. p E209-217.

Understanding the Heartbreak of Anosmia

If you can't perceive flavors that most other folks can, you may be anosomatic. Before you start looking for a specialist to cure the condition, you might thank your lucky stars instead. Or not. The specific compounds that were tested in “Specific Anosmia Observed for Beta-Ionone, but not for Alpha-Ionone: Significance for Flavor Research” reported by researchers from Danisco USA and USDA's ARS labs in Winter Haven FL include Beta- and alpha-Ionone, and beta-damascenone which are nor-isoprenoids widely found in plants and plant products as degradation products of carotenoids. They are used as flavor contributors in many fruit and fruit-based foods because they have low odor thresholds. These compounds are widely used: annual volumes of beta- and alpha-ionone used as flavoring agents in the 1970s in Europe were 2220 kg and 1100 kg, as reported by the International Organization of the Flavor Industry, yielding an estimated per capita intake of 310 and 150 micrograms per day. In the United States, reported annual volumes use of alpha-and beta-ionone in 1989 were 770 kg and 550 kg, respectively, with a per capita intake of 150 and 110 micrograms per day, respectively while the use of beta-damascenone was much lower).

According to the published report: “The specific anosmia found in 50% of the panelists tested for beta-ionone shows that if non-perceivers' thresholds were used to reconstruct a flavor, the resulting flavor would be distorted, possibly objectionable to perceivers. Therefore, great care should be used when using published thresholds by verifying the methodology to obtain them.” And so they did!p S401-406.

Scientific Status Summary Updates Mycotoxins

Mycotoxins were very much in the news a few years ago. The discovery that specific mold-derived toxins could cause grave human health problems caused a scramble to find and test methods to prevent the entry of mycotoxins into the food chain. This is the second Status Summary to address mycotoxins, and it emphasizes the discoveries that have taken place since 1986. The summary was completed by Patricia A. Murphy, Ph.D.; Suzanne Hendrich, Ph.D.; and Cindy Landgren, Ph.D., all of Iowa State Univ, and was reviewed by Lloyd Bullerman, Univ. of Nebraska – Lincoln; Charlene Wolf-Hall, North Dakota State Univ.; and Timothy Phillips, Texas A&M Univ.

Various toxins, including patulin, found in apples and occasionally in apple juice; ochratoxin, with a unique structure including chlorine; Zearalenone designated aflatoxin B1, B2, G1, G2, and M1, found in grains and often fed to animals; and trichothecenes, are known to exist but only a few are significant to humans. Fumonisins are found primarily in maize and occasionally in tomatoes and asparagus. The summary includes a great deal of data, studies of methods available and areas for improvements, and much additional information about the subject. Anyone that works with products that are likely to be infected by mycotoxins (or those working with foods that may become infected), should read the summary closely. p R51-65.

Electronic Nose Goes To Sea

According to researchers from the Fishery Industrial Technology Center Univ. of Alaska and Canadian Food Inspection Agency, the “Electronic nose (EN) is a relatively modern technology that may serve as an inexpensive and objective quality control tool for Alaska salmon processors. Research on the use of electronic noses for evaluation of seafood quality showed that EN sensors responses can be correlated with sensory analysis results for odor evaluation of a variety of fishery products such as cod, farmed Atlantic salmon, tilapia, catfish, yellowfin tuna, redfish, and cold-smoked salmon.” The “nose” can be used to check odors in salmon's belly cavities, which correlates well with final properties of canned salmon. Because the nose can be carried along, it can be used at various sites. However, it appears that there may need to be further development to reach the desired 95% accuracy in identifying the presence of spoilage organisms in whole salmon. p S414-421.