Many cereal proteins, such as wheat, corn, and oat proteins, have high levels of the amide-containing amino acids, glutamine and asparagine. These side chains are susceptible to hydrolysis of the amide bond, which leads to release of ammonia and transformation to acidic groups. The released ammonia has been implicated in the formation of aroma compounds and pigments because of its participation in the Maillard browning reaction. The conversion of the amide groups to acid groups may partially unfold the protein, resulting in an amphiphilic molecule that can be used as a surface active agent or emulsifier by food processors. This review provides general information on the factors that affect deamidation of proteins as well as the implications of deamidation for food processing.

Quality audit data collected as part of a mass feeding quality assurance program were analyzed to determine the relationships between the indicator tests (total aerobic plate count, coliform count and Escherichiu colz) and the common food-borne pathogens (Staphylococcus aureus, Clostridium perfringens and Salmonella). 132 raw foods and 593 readyto-eat foods were evaluated. The indicators were grouped into ranges and compared to the pathogens and to each other in terms of detectability. There were correlations between the pathogens and the indicator ranges and between the indicators and the indicator ranges. The value of the indicators in the e'valuation of food safety was tested by setting standards and determining the numbers of correct and incorrect decisions which would be made relative to the pathogens detected in the foods. None of the indicators was suitable as a screening agent for food safety.

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Extrusion cooking is a high-temperature/short-time process which is ideal for the production of flavor volatiles. However, due to the nature of this process there are many opportunities for these volatiles to be lost. This has led many researchers to study the formation and retention of volatiles during extrusion. This review focuses on the flavor-related reactions which may occur during extrusion, including their occurrence in various flours and due to the addition of reactive precursors.

Liquid smoke and heat treatments were evaluated for their potential use to inhibit growth of Aspergillus oryzae, Penicillium camemberti, and Penicillium roqueforti on Cheddar cheese. A. oryzae had a longer lag period and P. roqueforti grew faster radially on cheese heated at 42°C for 1 h than on unheated cheese. Mold growth on cheese heated at 24 and 33°C for 1 h was not significantly different from that on the unheated control. Liquid smoke applied to the surface of cheese totally inhibited growth of A. oryzae and significantly increased the lag period of P. camemberti and P. roqueforti. Of eight major phenolic compounds in smoke, only isoeugenol inhibited all three molds. P. camemberti was slightly inhibited by m-cresol and p-cresol, while A. oryzae was inhibited by guaiacol, 4-methylguaiacol, m-cresol, and p-cresol. Results of this study showed that phenolic compounds found in smoke are primarily responsible for inhibition of molds on smoked Cheddar cheese.