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将新鲜桑果粉碎加工成果汁,可以使桑果中大量的非可溶性膳食纤维如纤维素等成分得到充分利用.采用湿法超微粉碎方法对新鲜桑果进行粉碎加工,研究比较不同粉碎程度对新鲜桑果浆的理化特性及活性成分含量的影响程度,确定桑果的最佳粉碎粒径.结果显示:粉碎程度＜100目的桑果浆微粒粒径主要分布在100～300 μm之间,粉碎程度＞100目的桑果浆微粒粒径主要分布在0～50 μm之间;随着桑果粉碎程度增加,桑果浆的pH值、密度及固形物含量、紫外吸光度值呈增大趋势,浊度呈减小趋势,色度L*值、a*值和b*值均呈先增大后减小的趋势;当粉碎程度从20～40目增加到200目时,桑果浆中的游离氨基酸种类从19种增加到21种,游离氨基酸质量浓度由217.017 ng/μL增加到256.970 ng/μL,游离多酚、总黄酮、总花色苷质量比分别由1.93 mg/g、0.09 mg/g和0.49 mg/g增加到4.95 mg/g、0.31 mg/g和2.10 mg/g;粉碎程度＜100目的桑果浆中充满纤维,＞100目的桑果浆中纤维逐渐变成又短又细的微粒,均匀分布于溶液中.综合而言,粉碎程度＞100目的桑果浆的理化特性和活性成分含量受影响程度大于粉碎程度≤100目的桑果浆,实际生产过程中新鲜桑果的粉碎程度以100～ 200目为佳.“,”Processing fresh mulberry fruit into pulp enables full utilization of bulk insoluble dietary fibers such as cellulose.In order to provide optimum technical parameters for wet superfine grinding of fresh mulberry fruit,the effect of various grinding degrees on the physicochemical properties and active ingredients of fresh mulberry pulp was investigated.The results showed that particulate sizes from grinding degree of less than 100 meshes were mainly distributed between 100-300 μm,and those from grinding degree of more than 100 meshes were mainly distributed between 0-50 μm.As grinding degree increased,pH value,density,soluble solid content and ultraviolet absorbance of the pulp increased,turbidity of the pulp decreased,and chrominance L *,a* and b* values of the pulp all showed a first-increase then-decrease trend.When grinding degree was increased gradually from 20-40 meshes to 200 meshes,the number of kinds of free amino acids in mulberry pulp increased from 19 to 21,mass concentration of free amino acids increased from 217.017 to 256.970 ng/μL,and the mass ratios of free polyphenols,total flavonoids and total anthocyanins increased from 1.93,0.09 and 0.49 mg/g to 4.95,0.31 and 2.10 mg/g,respectively.Microstructure observation showed that mulberry pulp from grinding degree of less than 100 meshes was full of fibers,which were gradually changed into short and thin particulates blended uniformly in pulp solution from grinding degree of more than 100 meshes.In conclusion,grinding degree of more than 100 meshes had greater impact on physicochemical properties and active ingredients of mulberry pulp than that of less than 100 meshes.Therefore,grinding degree between 100-200 meshes is recommended in practical production of fresh mulberry pulp.