NUTRITIVE VALUE OF BREAKFAST CEREAL-MILK COMBINATIONS

The protein quality of 11 breakfast cereal-milk mixtures combined as normally eaten (1 oz cereal and 4 oz fluid milk) was determined by using a modified slope-ratio assay. Slope ratios (milk = 100) of three of the mixtures (oatmeal-milk, cream of rice-milk and shredded wheat-milk) were higher than that of milk alone. Using protein content and slope ratios it was calculated that 1 oz of the various cereals could increase potential protein value over that of milk alone by 26 to 117%, and that some of the mixtures could supply as much as 22% of the recommended daily allowance for an 8–10-yr-old child. It is suggested that information of this sort combining the protein quality of food mixtures as eaten with the protein content of a serving would be welcomed by consumers.     

Measurement of Interfacial Mechanical Properties in Fiber-Reinforced Ceramic Composites

Properties of the fiber/matrix interface in a SiC/glass-ceramic composite were investigated using an indentation method in Which a pyramidal indenter is used to push on the fibers and cause sliding at the interface. An ultralow-load indentation instrument was used to measure force and displacement continuously during loading, unloading, and load cycling. Frictional sliding and combined debonding/frictional sliding at the interface were analyzed. The analyses enabled the results to be used to provide a measure of the debond fracture energy, the magnitude of the frictional sliding stress, a measure of the uniformity of the frictional stress, and an indication of the sensitivity of the frictional stress to repeated sliding, varying load rate, and exposure to high temperatures.     

OPTICAL ASSESSMENT OF CORN OIL DETERIORATION DURING FRYING

The ultraviolet (UV), visible and near-infrared (NIR) absorption changes in corn oil were measured during processes simulating deep fat frying. Corn oil, maintained at 185C, was exposed to various treatments with nitrogen, air, water injection, air with water injection, and steam. Autoxidation due to a combination of air and high temperature in the simulated frying trials caused visible absorption changes between 400 and 580 nm as the oil deteriorated similar to those observed in potato frying experiments. These absorption changes were found to be associated with changes in an ultraviolet absorption band with a maximum near 270 nm. Second-derivative calibration equations developed at various visible and NIR absorption wavelengths successfully predicted the percentage of total polar materials (%TPM) which accumulated in the corn oil during simulated trials of autoxidation (R values from 0.93 to 0.98). Using spectral data from repetitive potato frying experiments, the predicted %TPM calculated with these equations correlated well with kinematic viscosity measurements (R values from 086 to 0.97).     

Component Interactions in the Extrusion Cooking Process: Influence of Process Conditions on the Functional Viscosity of the Wheat Flour System

Wheat starch, vital gluten and wheat flour solubles were processed in combination, in a single screw extruder. The paste viscosity profile and degree of cook of the starch component were used to assess interactive effects. The composite of all 3 components, simulating a wheat flour, was more cooked and gave thicker pastes than wheat flour itself when processed under the same extrusion conditions. The data suggest that the integral structure of wheat flour particles imparts a greater resistance to water penetration and cooking than when the individual components exist at random in a composite formulation.     

Modification of tempeh with the addition of bakla (Vicia faba Linn)

Bakla ( Vicia faba Linn), an indigenous pulse, was subjected to fermentation by the strains of Rhizopus oligosporus either alone or blended with soybean ( Glycine max ). Mycelial growth as viewed on the surface of the fermented mass was best obtained when strain NRRL 3271 was used. Increase in moisture content and pH during fermentation was highest in the case of strain NRRL 2710 irrespective of composition of bakla-soybean mixture. The tempeh, the fermented product, in each case had a mushroom-like odour, which was independent of the strain used. Bakla and bakla-soybean (up to 1:1 ratio) tempeh was free of beany flavour but this flavour increased as the soybean content of the blend was further raised and was perceptibly high when soybean content reached 75%. Bakla tempeh was more crisp than soybean tempeh. The crispness decreased with increasing soybean content.     

High-Resolution Techniques and Application to Nonoxide Ceramics

The microstructure of ceramic materials can be observed directly at the atomic level by using high-resolution electron microscopy. These techniques are described in detail and the new information that they reveal about ceramic microstructures is illustrated with examples of hot-pressed silicon nitrides, sintered silicon sarbide, and a "sialon" system.