Fine flour from corn and the isolated starch were dextrinized in the presence of acid and irradiated with y‐rays. Starch irradiated with high doses of y‐rays was highly modified while fine flour was less affected. The irradiated starch was reduced with sodium borohydride and then hydrolysed. Erythritol and other compounds were identified in the hydrolysate. It was concluded that the C2‐C3 bonds in the intermediate glucose units are probably broken by irradiation. Such hypothesis was confirmed by periodate oxidation, hydrolysis with α‐amylase and ferricyanide number determination of the irradiated starch.

The effect of addition of proteolytic enzymes to the steeping liquor of corn grains was studied to reduce the steeping period and to obtain starch of low protein content. For this purpose the intact, scratched and broken corn grains were steeped in presence of Alcalase and Neutrase enzymes. It was found that the steeping period decreased by about 50% in case of broken grains, while steeping intact or scratched corn grains in presence of the enzymes gave no effect.

CairoIt was found that the steeping of corn grains by using the usual counter-current system is more efficient for leaching protein than the continuous system. Artificial drying of corn grains at higher temperaturedecreases starch recovery and increases starch loss in byproducts. The scratching of presteeped corn grains reduced the steeping period by 40%. Storage of corn grains for a long period (9 months) reduced starch recovery by about 3%.

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