Acid urease derived from Lactobacillus fermentum was applied to reduce ethyl carbamate (EC) formation in California sherry production. Commercial sherry and sherry base were treated with urease under different conditions. Amounts of urea were determined and EC amounts were monitored by gas chromatography. Urea removal by acid urease reduced EC formation during the baking process and effectively maintained EC concentrations below the target level (90 µg/L). However, complete prevention of EC was not achieved because of precursors other than urea.

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Dynamic viscoelasticity and thermal characteristics of a model reduced fat pork sausage containing curdlan were investigated. Curdlan formed thermoirreversible gels during preparation of sausage at end point temperatures that were within the range in which such gels usually transform from thermoreversible to thermoirreversible. Dynamic viscoelasticity of curdlan gels and thermal characteristics of curdlan aqueous suspensions were analyzed to help explain the physicochemical behavior of curdlan gels in sausage. Once formed curdlan gels exhibited stronger thermoirreversibility with increasing concentrations. The thermoirreversibility could be attributed to the curdlan concentration being higher than the maximum theoretical curdlan to water ratio.

Modified VF-Bouillon agar with 0.5 mg/ml lithium chloride, 20 μg/ml sodium lauryl sulfate, 5 mg/ml sodium propionate, and 10 μg/ml neomycin sulfate was used with a triple-layer diffusion technique to selectively enumerate Bifidobacterium bifidum. Modified Brigg's agar was used to enumerate Enterococcus faecium. Modified Brigg's agar with 1,200 μg/ml streptomycin sulfate was used in a double-layer diffusion technique to selectively enumerate a streptomycin-resistant strain of Lactobacillus acidophilus. Selective enumeration of the individual bacterial components was compared to the mixture with an average 99% recovery of each component.

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