The Effects Of Irradiation On The Quality Of Barley For Beer Production

【Purpose】In order to lengthen the shelf life of the barley, control the length of the malt sprout, and increase the production of beer, the effects of irradiation on the germination of barley was studied, and the adequate dose of irradiation was determined. 【Materials and methods】The barley seeds were from Anhui seed station and were irradiated at the dose of 1, 3, 5, 7 or 9 kGy by 60 Co γ-ray. The indexes used to evaluate the quality of barley are germination rate of day 3 and day 5, length of the malt sprout, 1000-seed weight, water sensitivity, moisture, protein and starch contents, extract content, sensory test for malt sprout, water content of the malt sprout and the saccharification time. 【Results】1. The effect on the composition of barley. There was no significant difference in moisture, protein and starch content of the barley, and 1000-seed weight after irradiation at 1-9kGy. 2. The effect on the germination. The germination is a continuous process. There was no significant difference of the germination rates at day 3 and day 5 days when the dose was under 5kGy. Germination rate was decreased and the difference was significant compared with the control when the dose is over 7kGy. Irradiation can make it easy to control the length of the malt sprout and increase the yield of beer. The length is too short to meet the requirement of brewing after irradiation at 7 or 9 kGy. The water sensitivity was not affected at the dose under 5kGy but was at the dose over 7kGy. 3. The effect on the quality of malt sprout. The extract content of the barley was not affected at the dose under 5kGy, but was affected and could not meet the requirement of the brewing at the dose over 7kGy. The sensory test showed that the malt sprout irradiated at 1 or 3kGy was better than the control, irradiated at 5kGy was equal to the control, and irradiated at 7 or 9kGy was worse than the control. The water content of malt sprout was not changed after the seed was irradiated at 1 to 9 kGy. The saccharification time of malt sprout also was not changed at the dose under 5 kGy, and was significantly changed at the dose over 7 kGy which can not meet the requirement of the brewing.