Bovine longissimus muscle tenderness as affected by postmortem aging time, animal age and sex

Strip loins were removed from 10 bulls and 10 steers ～14 mo old and from 10 cows ≥ 44 mo. Samples were removed at 3, 7, 14, and 28 days postmortem. Shear-force values were measured. Sensory evaluation was done by a 15-member trained panel. Animal age and postmortem aging time had more influence on tenderness attributes than did sex of the animal. Increased postmortem aging time improved tenderness attributes regardless of sex or age.     

Steam Surface Pasteurization of Beef Frankfurters

Meat and poultry products are sources of foodborne bacterial contamination. We used flash steam heating followed by evaporative cooling to quickly reduce bacterial contamination on the surface of beef frankfurters without degrading appearance. The rate of heat transfer was studied by measuring surface temperature in a pressure chamber during steam heating. Quality changes were determined by measuring color and weight as functions of steam temperature and treatment time. Efficacy of the process was verified by microbiological experiments using L. innocua. Treatment times of 30–40 set at 115–136°C gave a 4 log reduction in bacterial counts on the surface without severely affecting color or weight. After long-term storage at 6°C and at 19°C, levels of bacteria on inoculated frankfurters remained reduced and there was no difference between treated and untreated products in color or weight.     

KINETIC ANALYLSIS OF THE FORMATION OF NITROSYLMYOGLOBIN

The formation of nitric oxide myoglobin (nitrosylmyoglobin) was followed in buffered solutions in which the concentrations of ascorbate, nitrite, chloride, myoglobin and hydrogen ion were varied systematically to determine their effect on the rate constants. The rate of formation of nitrosylmyoglobin was zero order with respect to the pigment. The orders for the other reactants were determined by plotting the zero order rate constants as functions of varying orders of each reagent to determine which order gave a linear plot. The results were used to develop a mechanism and a mathematical expression for the reaction. Two reaction sequences involving different nitrosating species were involved; 1, direct action of nitrous acid and 2, the formation of nitrosyl chloride. Both species then nitrosated ascorbate and ascorbic acid, by different mechanisms. The nitric oxide for nitrosylmyoglobin formation came from the nitrosated ascorbate.     

Moral Judgment and Crime Drama: An Integrated Theory of Enjoyment

The article proposes a theoretical framework in which moral reasoning about mediated crime and punishment is defined and combined with existing, affect-driven entertainment theory to yield an integrated theory of enjoyment. The authors analyze how crime dramas serve as statements about justice and then address how moral deliberation about the propriety of those statements impacts enjoyment. The authors report research findings to support the analysis of cognitive processing during crime dramas distinct from affective processing. The article also suggests future means by which the integrated theory of enjoyment can be examined.     

Protein Quality of Selected Muscle Foods as Affected by the Exchange of Dietary Wheat Bran for Cellulose

The exchange of 8.4% neutral detergent fiber (NDF) of wheat bran for 8.3% NDF of cellulose in diets containing either beef, chicken, fish or casein as protein sources did not (P>0.05) alter feed consumption, weight gain or energy intake in the protein efficiency ratio (PER) bioassay with weanling rats. Higher (P<0.05) fecal nitrogen (N) excretions and lower (P<0.05) N digestibilities occurred for each protein source when wheat bran was exchanged for cellulose. The exchange also had no effect (P>0.05) on PER or net protein ratio (NPR) of casein or fish protein or on NPR of chicken protein. However, PER and NPR of beef and PER for chicken were reduced (P<0.05) when the dietary fiber was exchanged.     

Physical-Chemical Characteristics of Partially Clarified Guava Juice and Concentrate

Partially clarified guava juice concentrate was prepared from single strength guava puree (5.5°Brix) by treatment with pectinase (2 hr at 50°C), extraction of juice with a rack-and-cloth press, and vacuum concentration to 23°Brix. The concentrate had the following characteristics: density, 1.10; pH, 3.16; total acids, 4.67%; ash, 1.51%; moisture, 72.4%; ascorbic acid, 867 mg%; viscosity, 4.4 cp; and CIE L* 39.2, CIE a* 10.33, CIE b* 27.11.     

Effects of Heat Treatments on the Head Yields of High Moisture Rough Rice

The influence of high temperature heat treatments on the head yields of rough rice having moisture in the range 18–30% wet basis was investigated using an experimental rotary conduction heating unit with constant agitation. Based on the time-temperature history of bulk grain, reaction kinetic parameters (F_c and z_c values) were determined for specified changes in head rice yields for general application. The estimated isothermal heating times (F_c values) were related to the reference bulk grain temperatures (T_ref) and initial moisture of rice samples (IMC). The plots of F_c value and T_ref led to the determination of z_c value and its dependence on the IMC of rough rice.     

Short-Time Breadmaking Systems. Effect on Oxidation

A spread test was used to study the effects of fermentation time and various agents on dough. Short fermentation times (15–30 min) greatly improved spread ratio. Yeast also improved spread ratio, particularly in combination with time. A combination of 60 ppm KBrO₃ and 100 ppm ascorbic acid was the most effective oxidant system. There was an obvious interaction between yeast and oxidants. Loaf volume was not affected by the timing of addition of yeast or ascorbic acid to dough. Potassium bromate was more effective when added at the premix. A 60 min rest between premix and remix consistently gave higher loaf volume when yeast was added, but not when both yeast and oxidants were present.     

N-Nitrosamine Analysis in Beer Using Thermal Desorption Injection Coupled with GC-TEA

A fast and sensitive method is described for determining a mixture of volatile N-nitrosamines in beer and other malt products. It consists of direct extraction of the sample with dichloromethane, volume reduction, cleanup by trapping volatiles onto Tenax-TA, and thermal desorption injection into a capillary gas chromatograph-thermal energy analyzer. Average recovery of N-nitrosodimethylamine added to beer ranged from 70 to 81%. N-Nitrosodimethylamine and N-nitrosopyrrolidine were detected in 10 samples of various domestic and imported beers analyzed. Total volatile N-nitrosamine concentrations ranged from 0.03 to 1.10 ppb in beer. Minimum detection limit of the method was 0.01 ppb for N-nitrosodimethylamine, a 10-fold increase in sensitivity compared to other similar methods.     

Carrot Dehydration—Optimization Process Studies on the Explosion-Puffing Process

A carrot dehydration process that includes the unique continuous explosion-puffing system (CEPS) is described. A drying study included moisture distribution throughout a two-stage pilot scale dryer as well as bed temperature during first stage drying. Shrinkage losses of carrots by two dehydration methods were investigated, and volume differences were obtained. Measurements of dried carrot properties such as bulk density, color, nonenzymatic browning, rehydration, and disintegration were used to determine optimum operating pressure, temperature, and feed moisture for CEPS. Response surfaces developed from these properties were used simultaneously to establish a constrained optimum.