This investigation is concerned with the cooling of 4-gal batches of custards and puddings from an initial temperature of 140°F to a final temperature of 60°F, using a rotating cold tube agitator. Variables were: (a) level of egg, (b) level of cornstarch, (c) level of sugar, and (d) rate of cold-tube agitation. Total cooling time decreased as the rate of agitation increased. All but one of the forty-eight mixtures cooled within 3 hr when agitated at 18 rev/min; all but five cooled within 5½ hr. when agitated at 6 rev/min. As the level of egg in the mixture increased the total cooling time decreased. As the level of sugar increased the total cooling time also increased, but the increase in total time was not in proportion to the increase in the level of sugar. In each instance, agitation at 18 rev/min produced a greater increase in radius of spread. Cornstarch was the most significant factor influencing the change in density of the mixtures. There was a greater increase in density value in the mixtures made with the high level of cornstarch than in the mixtures made with the low level of cornstarch. As the level of egg in the mixtures increased, the differences in density value also increased.
1This is part of a larger project titled “Heat Transfer in Foods Prepared and Cooled in Quantity.”