Milk was processed in two commercial plants and packaged in regular paperboard and plastic containers. Gallon containers were held at 40 to 45 F and exposed to 150 foot candles of fluorescent light for (a) 5 h, (b) 10 h plus 14 h in the dark, (c) 24 h plus 9 days in the dark, and (d) 10 days in the dark only. Vitamins A, thiamin, and niacin did not change significantly in milk in paperboard or plastic during storage under the different test conditions. The same was true of 17 amino acids and seven minerals (Fe, Ca Zn, Mg, Mn, Na, and P). A significant decrease in vitamin C occurred when milk in plastic or paperboard was exposed to fluorescent light for 5, 10, and 24 h. Riboflavin declined in milk in both types of containers when exposed for 10 and 24 h. Vitamin B6 was significantly less after milk was subjected 24 h to fluorescent light. These decreases were substantially less in milk in paperboard packages than in plastic containers.

No abstract

No abstract

Five brands of whole milk from retail stores were analyzed for quantitative vitamin changes when the samples had developed off flavor in storage at 10 C. Vitamins A, B6, and niacin decreased by a small but significant amount. Average concentration of thiamine, riboflavin, and B12 were not changed during bacterial growth. Cultures for Dagano cheese and yogurt and two strains of Streptococcus lactis decreased the contents of Vitamin A, riboflavin, and B12 during growth. The averages for thiamine and B6 content were not significantly changed. Niacin content was decreased by growth of each of the four cultures. Three strains of Bacillus subtilis and six other species of bacteria that caused off flavor in milk during growth produced no significant changes in contents of Vitamins A, B6, B12, and riboflavin. The mean contents of thiamine and niacin were decreased, but two species did not cause a decrease in niacin.

No abstract