Bilinear transformation of multivariable polynomials using the Horner method

The general bilinear transformation of a single-variable polynomial using the Horner method of synthetic division has been described by Davies (1974) and by Policastro (1979). The procedure, which is very simple to apply, is extended to multivariable polynomials     

Influence of Temperature of Fermentation on the Nutritive Value of Lactic Acid Fermented Cornmeal

Cornmeal was fermented 4 days at 25°C 35°C 45°C, and 55°C. Relative nutritive value (RNV) and concentrations of available (free) lysine, methionine, and tryptophan were determined for cornmeal fermented at each temperature and for nonfermented corn. Corn fermented at 45°C had the highest % RNV and amino acid levels of any of the groups tested.     

Effect of Pectin and Lignin on Mutagenicity in the Ames Assay

The effect of incorporating varying concentrations of pectin and lignin into the Ames assay with the known mutagens, benzo(a) pyrene, 3-methyl cholanthrene, and N-methyl-N-nitro-N-nitrosoguanidine, on mutagenic activity was investigated. The addition of 50 μg, 150 μg, and 300 μg concentrations of pectin and lignin failed to block the mutagenicity of benzo-pyrene and 3-methyl cholanthrene in the Ames/mammalian microsome assay using Salmonella typhimurium TA 98 and TA 100 with and without preincubation. The incorporation of 50 μg, 150 μg, and 300 μg of pectin and lignin did not block the mutagenic activity of MNNG in the Ames Spot test with Salmonella typhimurium TA 100.     

Effect of Nitrite and Sorbate on Total Number of Aerobic Microorganisms in Chicken White and Dark Meat Patties

The effects of nitrite, sorbate and combinations of these two ingredients plus salt on the number of aerobic microorganisms in chicken white and dark meat patties were examined. All patties were stored at 4–5°C for 12 days. Nitrite concentrations of 400 and 2500 ppm were effective in preventing bacterial growth in chicken white meat patties while 2500 ppm was required to prevent growth in dark meat. A reduction in bacterial growth (4–10 days) was demonstrated with 100 and 150 ppm nitrite in chicken white meat patties. Four hundred ppm nitrite reduced bacterial growth in dark meat patties for 6 days. In white meat patties, the use of sorbate (0.26%) in combination with nitrite (40 ppm) was as effective in reducing bacterial growth as higher concentrations of nitrite, salt (2.5%) alone or in combination with sorbate (0.26%) or nitrite (40 ppm) inhibited bacterial growth in both white and dark meat patties during the first 4–6 days of storage.     

MUTAGENIC ACTIVITY IN HEAT-PROCESSED FOODS AS DETERMINED BY THE AMES SALMONELLA/MUTAGENICITY ASSAY

Different concentrations of six commercially available heat-processed foods were screened for mutagenic activity using the Ames Salmonella mutagenicity assay. Bacterial strain TA 98 which detects frame shift mutations was used with S-9 mix prepared from livers of Aroclor 1254 induced rats for metabolic activation. Cornflake cereal, branflake cereal, and a breakfast replacement product were not mutagenic at 90 g concentrations or less. At concentrations of 20 g or above, liquid smoke was toxic to the bacteria. At lower concentrations of 1 and 5 g the bacterial colony survival rate was low, therefore no conclusions were made regarding its mutagenic behavior. A canned brown gravy was not mutagenic at concentrations of 75 g or less. A canned au jus gravy displayed moderately high levels of mutagenic activity of 100 g concentrations or less. The contribution of manufacturers'processing techniques to the formation of chemical mutagens in foods is discussed.