Table l-Composition of California small white beans /dry wt)California small white beans were soaked at different temperatures, in 10°C increments, from 20" C to 9O"C, until maximum imbibition was achieved. Losses of total solids, N compounds, total sugars, oiigosaccharides, Ca, Mg, and three water-soluble vitamins (thiamin, riboflavin and niacin) were measured and found to be very small at soaking temperatures up to 50°C. An increase in those losses of from three-to fourfold was found when the soaking temperature was raised to 60°C or above. Cooking rates followed a bell-shaped pattern with the peak, longest cooking time, being for beans soaked at 70°C and shortest cooking time for beans soaked at 90°C. Cooking rates corresponded closely to the amount of organic phos phate left in the beans after soaking at the different temperatures.

Storage of dry beans under conditions of relatively high moisture and temperature increased the cooking time of the beans about 5‐fold. Among the changes that occur in beans stored in this way, the reduction (about 65%) in phytic acid content was the best indicator of increased cooking time. Cooking times of various legumes studied correlated well with the ratio of % phytic acid/% Ca present in the beans. Soaking high moisture beans in a solution of either phytic acid or EDTA reduced cooking time to that of control beans. Cooking time of control beans soaked under the same conditions was reduced by between 1/3 and 1/2, depending on the solution used.

SUMMARY— Grinding dry California Small White beans or Lee soybeans under acid conditions inhibited lipoxidase in the seeds and resulted in bland legume slurries and “milks.” Sensory evaluation and gas chromatography were used to determine the effect of processing method on flavor. Off‐flavor development was suppressed at pH 3.85 and below; acidification to about pH 2.0 was necessary to obtain maximum protein extraction in the preparation of legume “milk.” Acceptable bland products were obtained from the slurries by neutralization after heating.

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