The Effect of Chitosan Oligosaccharides on Barley Germination and Malt Quality

Chitosan oligosaccharides(COS) is the only positively charged bioactive natural products in nature and has excellent properties of biocompatibility and biodegradability, and has been widely used in the agriculture field, the well performance of the seed gemination, plant growth and the yield of crops indicated the COS of its good effect. The effects of COS added during malting on the qualities of barley and malt and malt growth were studied in the experiments.⑴Different COS concentrations were added in malting to study its effects on grmination rates and the quality of malt. Results showed that germination rate of domestic barley was raised up to 12.82%, and the content of a–amylase, β-amylase and a-amino nitrogen increased 9.02%, 16.45% and 23.96% compared with contrast, respectively, while the β-glucan decrease by 14.87%。The content of glucose and maltose in wort also increased.⑵The effect of different malting technology on barley germination was studied, fluorescence labeling and the detemination of the content of organic acids was used to research the mechinism of accelerating germination of barley. And accelerating germination of COS was mainly reflected in innitial germination. Bright green fluorescence could be discovered on husk and embryo after barley was steeping into FITC-COS, but there was nothing in the endosperm. oxalic acid, citric acid, malic acid and lactic acid was Determinated by HPLC, which may effect on the acide enviroment inside.⑶Malt quality and beer brewing could be mostly effected by mold growth, the effects of different COS and chitosan and different COS concentration on Alternaria, unknown black mold, Rhizopus, Rhizopus oryzae and Geotrichum candidum were studied, it showed good effect, and higher concentration had better antimicrobial effects.