Control of phenol oxidase activity in apple slices by the use of ascorbic acid at different pH values, temperature and time of incubation was investigated. The enzyme was almost inactivated at 1% and 1.5% ascorbic acid. Ascorbic acid solution (1%) caused a remarkable inhibition with the increasing acidity up to pH = 1. Heating treatments for apple slices dipped in 1% ascorbic acid caused a reduction of enzymatic browning, optimum temperature for inactivation of the enzyme was between 60-70 degrees C for 15 minutes. Increasing the time of dipping apple slices in 1% ascorbic acid solutions and at different pH values reduce phenolase activity.

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Scanning electron microscopy was used to study changes in microstructure of broad beans during the germination process. Photomicrographs showed only slight differences in the appearance of cotyledon cell structure between the dry and soaked broad beans, but the size of the starch granules increased after soaking. Also scanning electron micrographs of the cotyledons and the starch and protein fractions of broad beans revealed changes in the surface of the cells during germination of the seed. The starch granules appeared to be very fragile and proteins began to break into small fragments after 8 days of germination. There was a decrease in amylose, amylopectin, and raftinose during germination. Sucrose and fructose increased during the 4-day germination period, but decreased thereafter. Raffinose decreased gradually during the O-6 day germination period, and was not detectable after 8 days.