Marilynn Schnepf

Development and application of multicomponent edible coatings and films: a review.

Combining the advantages of polysaccharides, proteins and/or lipids offers multicomponent edible films and coatings good mass transfer barrier properties. Multicomponent edible films and coatings could be beneficial to the food industry by leading to innovative applications. The barrier properties of these systems strongly depend upon their structure and chemistry, the interaction between different film components as well as surrounding environment conditions. Future researches on these multicomponent systems need to concentrate on the following goals: (1) investigation of the optimal film compositions and specific film-forming conditions for different food systems; (2) study of the film responses in their barrier properties to environmental factors such as RH and temperature; (3) fundamental research of the mechanism of mass transfer and the interaction of different films components and foods; (4) exploration of the feasibility of potential applications in the food industry.

Use of Edible Films and Tocopherols in the Control of Warmed Over Flavor

Abstract Growing demands of consumers for convenience has increased the market for frozen food entrees. This has challenged the meat scientist to find new methods of improving the quality of precooked meat items. Warmed over flavor (WOF) development has been identified as a problem in precooked meat products. Edible films and natural antioxidants are known to inhibit WOF and may improve precooked meat quality. Film physical property testing demonstrated that the ZN films had lower % elongation and tensile strength compared to SA films. Oxygen permeability (O 2 P) of the SA films was 0.613–5.818cm 3 .μm/m 2 .d.kPa, whereas water vapor permeability (WVP) was 5.20–7.09g.m/s.Pa and 5.61–6.12 × 10 −9 g.m/s.Pa for the SA and ZN films respectively. After physical property determination, the following five film treatments were applied to the chops: control, SA, starch alginate + 4% (w/v) TOC (SAT), ZN, and zein + 4% (w/v) TOC (ZNT). Thiobarbituric acid reactive substance test (TBARS) was performed on 0, 3, 6, and 9 days of refrigerated storage, and sensory panelists determined off-flavor and juiciness on days 0, 3, and 6. TBARS values for the chops coated with the SAT, ZN and ZNT films were significantly lower than control and SA treated chops on days 6 and 9. Sensory panelists rated samples coated with SA and SAT as significantly juicier than other treatments and SAT, ZN, and ZNT as having significantly higher off-flavor on all days. The SAT, ZN and ZNT films appeared to be lowering the amount of lipid oxidation as shown by the TBARS but may impart an off-flavor. With the removal of unwanted flavors from edible films and natural antioxidants, their application may help improve the quality of precooked meats used in convenience food products.

Protein-Water Interactions

Water is one of the most important molecules necessary to sustain life. It is the only substance found in all three physical states. The interaction of water with other substances is critical to most chemical and biological reactions. Proteins also play an important role in many life processes. They provide structure to living cells and regulate many cellular functions. The interaction of these two important molecules plays an important role in determining the functional properties of many food ingredients. The focus of this chapter is to discuss the types of bonding which occur between water and protein molecules and to relate the interaction between water and protein molecules to the functional properties of proteins in foods.

Vegetable Choices and Cookery Methods of Nebraskans

A telephone survey of a random sample of adult Nebraskans was conducted to identify the vegetables they consumed and the methods they used to cook these vegetables. Subjects were called in the evening after the last meal of the day, and were asked to respond to questions about the vegetables they had eaten that day. Results indicated 15% of the 538 respondents did not eat a vegetable on the day they were contacted, 26% ate 1 vegetable, 25% ate 2 vegetables, and 34% ate 3 or more vegetables. Mean vegetable consumption was 2.2 vegetables per person per day. Twenty-one different vegetables were eaten and 4 of these, potatoes, lettuce, carrots, and tomatoes, accounted for 48% of vegetables consumed. One third of the vegetables were eaten raw. When they were cooked, the cookery method used most often was on the stove top (i.e., boiling). This method was used more than twice as often as the microwave for cooking vegetables. Results of this survey indicate that nutrition education programs need to encourage increased vegetable consumption and the use of vegetable cookery methods that maximize nutrient retention.

Effect of Cooking Method, Distiller's Grains, and Vitamin E Supplementation on the Vitamin Content of Value Cuts from Beef Steers Fed Wet Distiller's Grains and Solubles and Supplemental Vitamin E

Vitamin E, thiamin, riboflavin, niacin, vitamin B(6), and vitamin B(12) concentrations of flat iron steaks and petite tenders from steers fed finishing rations containing 0% and 40% corn wet distillers grains and solubles (WDGS) with and without supplemental vitamin E were determined. Feeding treatment groups were: 0% WDGS with basal vitamin E, 0% WDGS with supplemental vitamin E (500 IU daily), 40% WDGS with basal vitamin E, and 40% WDGS and supplemental vitamin E. Cattle can be fed 40% WDGS diets more economically than corn diets. The incorporation of 40% WDGS, with and without vitamin E, was hypothesized to have little effect on the vitamin concentrations of these value meat cuts. Flat iron steaks and petite tenders were broiled and/or grilled to 70 degrees C internal temperature. Mean cooking yields ranged from 68.7% to 78.2%. The majority of the vitamin concentrations of broiled and of grilled meat were significantly different (P < 0.05) from that of raw meat. Vitamin E concentrations of raw and cooked meat from steers that received supplemental vitamin E were significantly higher (P < 0.05) than those fed basal vitamin E. Significant differences in thiamin, riboflavin, vitamin B(6), and vitamin B(12) concentrations in raw flat iron steaks and in vitamin B(6) in raw petite tenders were observed by WDGS. Thiamin, vitamin B(6), and vitamin B(12) concentrations of broiled flat iron steaks were significantly different (P < 0.05) than grilled. A few differences in vitamin concentrations of the flat iron steaks and petite tenders were observed by WDGS, vitamin E supplementation, and cooking treatments, but most of the vitamin concentrations were statistically similar.

Cooking System Interactions: Compatibility of Energy Source and Container Material

A laboratory experiment was performed to investigate the interaction between energy source and container material in surface cooking operations as deter mined by evenness of heating, speed of heating, and heat retention. Energy sources were a conventional gas burner; a conventional electric coil; an electric resistance heater and induction coil, both under glass-ceramic; and a solid elec tric element. Cookware of thin- and heavy-gauge aluminum, porcelain enamel over thin-gauge steel, heavy-gauge stainless steel with a thick aluminum heat core, and glass-ceramic was combined with each of the energy sources to com plete a cooking system. A General Linear Models Procedure was used to assess statistically the impact of each variable on test results. Duncan Multiple Range tests were performed to identify statistically significant differences between sys tems. Heavy-gauge aluminum and heavy-gauge stainless steel with a thick alu minum heat core produced the most even browning of crepes in all cooking systems. Regardless of the cookware used, the induction unit, gas burner, and conventional electric coil boiled water more quickly than did the other energy sources, while the solid element and the electric resistance coil under glass- ceramic retained more heat.

Impact of Ingredient Ratios on Ground Beef Loaf Quality

Abstract LEARNING OUTCOME: to develop a model ground beef loaf system which would be he basis for developing reduced fat meatlof products. The emphasis on healthy, low fat diets and the decline in beef consumption have resulted in attempts to reduce fat calories in comfort foods. Response surface methodology was utilized to predict an optimum ground beef loaf. A Box-Behnken design consisting of the following treatments: {distilled water (DW) (45, 51, 57, 63, 69g); bread crumbs (BC) (30, 33, 36, 39, 42g); egg whites (EW) (51, 54, 57, 60, 63g); and ground beef fat (GBF) levels (10, 13.3, 20, 26.7, 30%)} were evaluated in a meat loaf formulation comprised of 447g ground beef and 0.3g salt. Variables evaluated were yield, proximate composition (PC), cookout (CO). Instron Lee Kramer, pH, and water holding capacity (WHC). Sensory attributes (juiciness, firmness, mouthfeel, flavor, and overall acceptability were measured using a hedonic scale (5=like extremely and l=dislike extremely). The Statistical Analysis System (SAS) response surface regression was used for model determination. Individual response surface models for yield, sensory, PC, CO, Instron, pH, and WHC did not indicate an optimum response. However, meatloafs formulated with reduced ground beef fat levels (10%) increased yield from 80.2% to 85.2%. Similarly, high levels of egg whites (63g) and bread crumbs (42g) increased yield. A SCORE {SCORE = l(Sensory) + 12(Yield + WHC) + 13(Instron) + 14(PC) + 1 / 5 (CO) + 1 / 6 (pH)} was generated using weighted linear combinations of the variables. Procedure regression with stepwise selection was used to maximize the coefficient of determination and select the maximum score. Formulations with scores above 15 were selected for further evaluation. Two formulations {(45g DW, 42g BC, 63g EW, 10% GBF (LWHB); 69g DW, 30g BC, 63g EW, 10% GBF (HWLB)} were evaluated. A higher cooked yield (86.4%) was obtained from the LWHB formulation. With the current emphasis on healthy and low-fat diets, this ground beef loaf formulation was not only nutritionally healthy, but also palatable.

Evaluation of Es/wic Initiative for Latino Women

Abstract LEARNING OUTCOME: To examine nutrition education on pregnancy outcomes of WIC eligible Latina women. The objective of this research was to evaluate the impact of supplementary nutrition education and support by Expanded Food and Nutrition Education Program (EFNEP) bilingual peer paraprofessionals on Spanish speaking, WIC eligible Latina women. The study included 40 WIC-only control subjects and 29 intervention subjects who were enrolled in both WIC and EFNEP. Breast-feeding (BF), practices, birthweights, hemoglobin values, and pre/post 24-hour food recalls were obtained by searching WIC files. Nutritional behaviors and opinions were obtained from a Spanish version of a pre/post EFNEP Survey. Data were statistically analyzed using SAS. Significance was set at p≤.05. Intervention subjects from one site attained 100 percent BF initiation rates, and continued to BF for an average of 16.9 weeks, significantly more than control subjects who initiated BF at a rate of 67 percent and continued to BF for an average of only 7.8 weeks. Intervention subjects increased their intakes of grain products, fruits, vegetables and milk significantly more than control subjects. Intervention subjects ran out of food less often than controls, and they examined food labels for fat more frequently than controls. Considering the rapidly growing population of Spanish speaking clientele at WIC, expanded efforts of cooperation between EFNEP and WIC may enhance efforts to promote breast-feeding in this ethnic group. Interagency teamwork may also help ethnic clientele to increase their use of food labels, influence desirable eating practices during pregnancy, and optimize resources.

Copper status of mice fed hydrogenated vegetable oil, cocoa butter, fresh and cured pork from high and low nitrate/nitrite containing diets

Abstract The objectives of this study were to determine the effects of hydrogenated vegetable oil, cocoa butter, fresh and cured pork from high (spinach = 0.2%) and low (spinach = 0.02%) nitrate/nitrite containing diets on copper status of mice. The dietary treatments had no significant effects on urinary and fecal copper excretions and whole blood and liver copper contents of mice. However, there were significant (p