选用超微、石磨、钢磨、湿磨4种磨粉方式对苦荞籽粒进行磨粉,分析比较苦荞粉破损淀粉含量、粒径分布、微观结构、水合特性、冻融稳定性、黏度特性等粉质特性并采用酶解法模拟体外淀粉消化测定不同时间点的总淀粉水解率.研究结果显示:磨粉方式对苦荞粉粉质特性及体外消化特性影响差异显著,其中超微粉碎能显著减小苦荞粉粒径大小(D[4,3] =32.09 μm),提高其亮度值(L =88.92)以及淀粉对酶的敏感度;湿磨粉淀粉颗粒形态完整,破损淀粉质量分数最低,为4.25％,冻融稳定性好,回生值低(3732 cP),不易老化;石磨粉粉糊衰减值低,粉糊热稳定性好,淀粉水解缓慢;刚磨粉对各项指标的影响均不突出.不同磨粉方式对苦荞粉的影响不一,超微粉是一种理想的苦荞深加工食品原料,湿磨粉则适合冷冻食品加工,石磨粉更适合慢消化食品加工,而刚磨粉适合与普通食品用粉.%Four types of milling metheds,including ultrafine milling,stone milling,steel milling and wet milling,were used in this study to prepare tartary buckwheat flour.The damaged starch,particle size distribution,microstructure,hydration characteristics,freeze-thaw stability,pasting properties and in vitro total starch hydrolysis through enzymolysis at different times of milled flours were measured.The results indicated that milling methods had a significant effect on the characteristics and in vitro starch digestibility of tartary buckwheat flour.Ultrafine milling reduced the average particle size (D [4,3] =32.09 μm),increased bright color (L =88.92) and susceptibility to enzyme.Wet milling flour had the lowest damaged starch content (4.25 ％),lower setback value (3732 cp),the most intact starch molecule structure and the best freeze-thaw stability.Stone milling flour had the best thermal stability and lowest breakdown value and starch hydrolysis rate.Steel milling had no significant effect on all parameters.In summary,different milling methods had different effects on the characteristics and in vitro starch digestibility of buckwheat flour,ultrafine buckwheat flour could be considered as an ideal raw material for further processing,while wet milling and stone milling flour were more suitable for frozen food processing and slow digestion food individually,and steel milling flour could be used as material for common food.
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