Sorption of carbon dioxide by milk powder in a closed system at 35 °C. and at approximately 74 cm. of mercury was observed to be greater than 0.4 cc. per gm. after 150 hr., while only 0.012 cc. of nitrogen was absorbed per gm. after 70 hr. The initial sorption of carbon dioxide varied with time according to the equation:[Formula: see text]where s is 100 times the amount sorbed in cc. per gm. at any time, t (min.), and k and m are constants peculiar to the system under investigation. The logarithmic form of this equation was used. Powders with 26, 28, and 30% fat did not differ in behaviour, but sorption curves for powders with only 1% fat had lower [Formula: see text] values and lower [Formula: see text] values than the curves for the high fat levels. Powders with 1% fat sorbed carbon dioxide in an identical manner when exposed to either 100% carbon dioxide or a mixture of 20% carbon dioxide and 80% nitrogen. For whole milk powder, dilution to 80% nitrogen content was effective in reducing the initial sorption rate of carbon dioxide. Great variation was observed in the sorption behaviour of powders from different plants and in powders produced at different time intervals in the same plant. Temperature differences within the range 25° to 40 °C. had no effect on sorption. Palatability and [Formula: see text] correlated to the extent of r =.61.
Mathematical models for the biofilm formation of Geobacillus and
Anoxybacillus on stainless steel surface in whole milk
