Three Methods for Determining Nonheme Iron in Turkey Meat

The ferrozine, the Schricker and modified Schricker methods were used to measure the non-heme iron in raw and cooked turkey meat. The ferrozine method gave the lowest non-heme iron values, while results from the Schricker and modified Schricker were not different (p<0.05). When hemoglobin (Hb) was added to breast meat, how-ever, differences (p<0.05) between the Schricker and modified Schricker, and Schricker and ferrozine methods were observed in cooked meat with NaCl. Cooking and addition of NaCl caused increase in measured nonheme iron content and had a synergistic effect on the release of nonheme iron in meat.     

Prevention of Lipid Oxidation in Precooked Turkey Meat Patties with Hot Packaging and Antioxidant Combinations

The effects of antioxidants or hot packaging and their combination on lipid oxidation were quite variable depending on the additives in turkey meat. The TBARS values of cooked patties were greatly affected by the degree of oxidation in the raw meat, and the effectiveness of antioxidants varied with added prooxidants. Ascorbate and free radical terminators had stronger antioxidant effects than iron chelators, and chelating iron alone could not eliminate lipid oxidation in either raw or cooked meat with added NaCl. The combination of hot packaging and antioxidants provided cooked patties with better protection from lipid oxidation than either treatment alone.     

EFFECT OF WATER ACTIVITY ON THE GROWTH OF STAPHYLOCOCCUS AUREUS AT MEAT-CHEESE INTERFACES

There is increased marketing of ready-to-eat nonrefrigerated snack foods which consist of meat or sausage products with low or intermediate moisture levels combined with high moisture food products, i.e., cheese products. Packaging the intermediate moisture meat in direct contact with a high moisture food might change the water activity (a_w) of the products sufficiently to support growth of Staphylococcus aureus at contaminated interfaces. To evaluate this possibility, sterile sausage slices (a_w= 0.60 to 0.82) were surface inoculated with log 2-3 CFU/g of S. aureus, interfaced with processed cheese slices (a_w= 0.94), vacuum packaged, and incubated at 19, 28, 37C and at cyclic temperature of 19–37–19C. S. aureus levels and water activities were determined weekly for 0 to 9 weeks. The a_w at the interface changed rapidly and reached an a_w that supported S. aureus growth. Growth of S. aureus occurred under all test conditions when the samples were stored at 28 and 37C. At 19C storage S. aureus remained viable for the length of the study.     

DEVELOPMENT OF STRESS AND SURVIVAL OF SALMONELLA TYPHIMURIUM ATCC 7136 IN A TAPIOCA SOYSTARCH PRODUCT CONTAINING POTASSIUM SORBATE

The effects of reduced water activity and 0.1% sorbate on Salmonella typhimurium ATCC 7136 in a soy-starch product were examined. The formulated product (final pH 6.7), was inoculated with cells to give a final concentration of approximately 2 × 10⁶ cells/g. Ten gram samples were placed in a series of desiccators over saturated salt solutions and stored at either 22°C or 40°C. Water activities ranged from 0.79 to 0.97. Samples were withdrawn at prescribed intervals and appropriate dilutions made. A dual plating procedure was used to monitor growth (tryptic soy agar) and development of injury (Levine's Eosin Methylene Blue Agar supplemented with 2% NaCl and 0.05% sodium desoxycholate). Cells stored at 22°C remained viable longer at an a_w of 0.79 than at a_w values of 0.96 to 0.97. As storage time increased, cells were stressed at a faster rate at higher a_w values. This effect was accelerated at 40°C and as storage time increased.     

Effects of Potassium Sorbate Alone and in Combination with Sodium Chloride on the Growth of Salmonella typhimurium 7136

The effects of potassium sorbate alone and in combination with 2 or 3% sodium chloride (NaCl) on the growth of Salmonella typhimurium ATCC 7136 were examined. Growth studies were performed in tryptic soy brogh (adjusted to a final pH 6.3) at 22°C for 15 days and 35°C for 48 hr without shaking. A dual plating procedure was employed to monitor growth (tryptic soy agar) and development of injury in the cell population (Levine's eosine methylene blue agar + 2% NaCl + 0.05% sodium desoxycholate). The difference between these two plate counts served as a measure of the number of injured organisms. It was found that combinations of sorbate and NaCl were more effective in the inhibition of S. typhimurium than sorbate alone under the conditions and variables studied. No injury was observed in the cell population as determined by our assay procedure. The combination of 3% NaCl + 0.3% potassium sorbate was the most effective in inhibiting growth of S. typhimurium at either storage temperature.     

An implementation perspective of applying object-oriented database technologies

As a result of improvements in information technology, more system designs and implementations require data-intensive applications. The most promising approach to solving these problems is the object-oriented database architecture. Unfortunately, object-oriented database management systems have not matured. Lack of agreements in the data models and formal foundations have created problems in using them. However, systems are being designed and developed with object-oriented philosophies even though important issues still need to be resolved. This paper examines the important issues in designing an object-oriented database prototype from three perspectives: object technologies, database technologies, and application environments. Each issue is discussed separately and illustrated with C++/Versant.     

Pb5(Ge,Si)3O11 Ferroelectrics

The compound Pb₅Ge₃O₁₁ is an optically active ferroelectric with a transition temperature near 177°C. Solid solutions containing up to 62% Si replacing Ge were prepared from the melt. Increasing the Si content lowers the melting point, Curie point, and coercive field. Permittivity measurements on single crystals indicate a simple second-order phase change.     

CONSUMPTION OF RISKY FOODS AMONG ADULTS AT HIGH RISK FOR SEVERE FOODBORNE DISEASES: ROOM FOR IMPROVED TARGETED PREVENTION MESSAGES

Foodborne disease is of particular concern in populations at risk for severe consequences, including the elderly and persons with immune‐compromising conditions. Using data from the Foodborne Diseases Active Surveillance Network (FoodNet) Population Survey, we examined the association of risky food consumption with gender, age, immune status, income and education. Gender, age and immune status were associated with consumption of risky foods. More males than females ate at least one risky food while persons aged ≥65 years were less likely than those 18–44 to eat risky foods. In the 18–44 group, those with immunosuppressive conditions were more likely to eat risky foods (P < 0.001). In the ≥65 group, those taking immunosuppressive drugs were more likely than healthy persons to eat risky foods (P < 0.001). Our findings suggest that young adults with immune‐compromising conditions and elderly persons who take immunosuppressive drugs report eating more risky foods than their healthy counterparts.