PREVALENCE OF SELECTED UNSAFE FOOD-CONSUMPTION PRACTICES AND THEIR ASSOCIATED FACTORS IN KANSAS1

Results of a survey conducted between 1995 and 1996 in Kansas were analyzed to estimate the prevalence of four high-risk food-consumption practices and to identify population characteristics associated with each practice. The self-reported prevalences were 26.5% for home-canned vegetables, 8.7% for undercooked hamburger, 55.6% for raw or undercooked eggs, and 1.8% for raw milk. Rural residents and those who had a child between ages 13 and 17 were more likely to consume home-canned vegetables. The consumption of undercooked hamburger was low for respondents with a child from one to four years old but was high for overweight respondents. Those respondents who had higher education and a child between ages 13 and 17 were more likely to consume raw or undercooked eggs. Lower income respondents were more likely to drink unpasteurized milk. The population characteristics identified in this study could be incorporated in the formulation and implementation of educational programs aimed at changing these high-risk eating behaviors.     

FLAVOR AND CHEMICAL CHARACTERISTICS OF CONVENTIONALLY AND MICROWAVE REHEATED PORK

Sensory evaluations and chemical measurements were made on freshly cooked (conventionally heated), conventionally-reheated (after 5 wk frozen storage), and microwave-reheated pork loin muscle. Freshly cooked and microwave-reheated pork had sweeter aroma and less metallic flavor than conventionally-reheated pork. Microwave reheated pork was less juicy than pork heated by the other treatments. Freshly cooked pork had the lowest TBA values and the highest moisture content. Heating treatment did not affect ninhydrin-reactive compounds or nitrogen content in the various extracted protein fractions.     

Glycine Loss and Maillard Browning as Related to the Glass Transition in a Model Food System

The effects of water activity and the glass transition on the rate constants for glycine loss and brown pigment formation due to the Maillard reaction were evaluated in a model food system. Equimolar glucose and glycine were incorporated into amorphous polyvinylpyrrolidones of various molecular weights and moisture contents. Glycine loss and brown pigment formation were quantified during storage at 25°C. At constant water activity, rate constants were higher in systems with lower glass transition temperatures. Glycine rate constants decreased upon matrix collapse, but browning rate constants were not affected by collapse. Changes associated with the glass transition influence bimolecular reactions and should be considered during product formulation and shelf-life testing.     

EFFECT OF STORAGE CONDITIONS ON THE SENSORY QUALITY OF GROUND ARABICA COFFEE

The objective of this study was to determine how long ground coffee beans could be stored at room and freezing temperatures before sensory changes could be detected, and to identify specific attribute changes associated with this storage. Ground beans were stored for 0 (fresh), 1, 2 and 3 weeks at room and freezing temperatures. Coffee was prepared from each of these treatments and difference testing was performed. Paired comparison tests were conducted on the fresh, 1‐ and 2‐week‐stored coffee grounds to examine the attributes of coffee aroma, flavor, bitterness and overall preference. At room temperature storage, results indicated significant (P < 0.05) differences in the coffee prepared from fresh versus the 2‐week‐stored ground beans. Coffee made from freshly ground beans had a stronger coffee aroma, less bitterness and was more preferred compared with the beans stored for 1 or 2 weeks (P < 0.05). At freezer storage, differences were detected between coffee prepared from coffee grounds stored for 1 or 2 weeks. Coffee prepared from grounds stored for 2 weeks had a stronger coffee aroma and was more bitter compared with the other storage times (P < 0.05).     

COMPOSITION OF CARBOHYDRATES AND CONCENTRATION OF β-GALACTOSIDASE OF COMMERCIAL FROZEN YOGURT

Commercial frozen yogurt samples were analyzed for composition, β-galactosidase activity, and microbial quality. The composition of protein, fat, sugars, other carbohydrates, and total solids varied considerably among the 11 brands tested. All samples contained high levels of lactic acid bacteria (> 6. 0 log cfu/mL), as well as active β-galactosidase but the enzymatic activity varied greatly (1.04 – 43.12 ONP units) among samples. A significant correlation (r = 0.785) existed between β-galactosidase and lactic acid bacteria concentrations. The major sugars in samples were sucrose (0–12.7%) followed by lactose (2.31–4.25%) and glucose (0.74–2.49%). The sugar extraction method developed for the HPLC analysis gave reliable and reproducible data, despite the fact that frozen yogurt samples contained a wide variation in fat, protein, and total solids contents.     

Turbot Fillet Sections Cooked by Microwave and Conventional Heating Methods: Objective and Sensory Evaluation

Greenland turbot fillet sections were baked in conventional and microwave ovens. The microwave oven cooked the fish faster, required less energy, and demonstrated greater relative efficiency than did the conventional oven. Solid-drip and total cooking losses were greater and Kramer shear values and evaporative loss were lower for microwave-heated fish. No differences in sensory flakiness and moisture were found between oven treatments, but microwave-heated samples were rated softer and less chewy by a trained panel. Several significant correlations were found among sensory attributes and objective measures of quality. A 39-member consumer panel indicated no differences in acceptability of turbot heated by the two cooking methods.