脱脂、脱蛋白处理对板栗粉膨胀势的影响

 【目的】比较3个品种群的24个主栽品种板栗粉膨胀势及其脱脂、脱蛋白处理后膨胀势变化的差异，分析板栗粉的主要物质组成与其膨胀特性的关系，为板栗粉加工产品的研制提供理论依据。【方法】采用冷冻干燥法制取板栗全粉，索氏提取法制取脱脂板栗粉，碱液沉淀法制取脱蛋白板栗粉，索氏提取法和碱液沉淀法制取脱脂脱蛋白板栗粉；采用吸水膨胀离心法测定系列板栗粉膨胀势，凯氏定氮法测定蛋白质含量，索氏提取法测定脂肪含量，蒽酮比色法测定淀粉含量。【结果】板栗全粉的膨胀势在不同品种之间以及不同品种群之间均存在差异，其中北方品种群板栗全粉膨胀势最低。脱脂处理对板栗粉膨胀势的影响相对较小。各品种板栗粉脱蛋白处理后膨胀势均显著升高，脱蛋白板栗粉膨胀势以及膨胀势的变化值均在品种间存在差异。脱脂脱蛋白处理使大部分板栗粉膨胀势显著升高，不同品种之间存在差异，且脱脂脱蛋白板栗粉膨胀势按照北方品种群、中间类型品种群和南方品种群的顺序依次降低，其中北方品种群和南方品种群之间差异显著。板栗粉中的淀粉含量、蛋白质含量和脂肪含量在各品种之间存在差异，淀粉含量与板栗粉膨胀势存在显著相关性。【结论】淀粉是影响板栗粉膨胀势的重要因素，板栗粉中的蛋白质和脂类物质的共同作用显著影响板栗粉的膨胀势特性。脱脂、脱蛋白处理使板栗粉膨胀势发生改变，脱脂处理对板栗粉膨胀势影响相对较小，脱蛋白处理使板栗粉膨胀势显著增加，这种变化趋势及变化量与品种密切相关，并在一定程度上具有地域分布特性。

Effect of De-Fat and De-Protein Treatments on Swelling Power of Chinese Chestnut(C.mollissima Bl.) Powder

【Objective】 The experiments were conducted to compare the swelling power of chestnut native powder of 24 cultivars of Chinese chestnut (Castanea mollissima Blume) from different cultivar groups, and investigate the effect of de-fat and/or de-protein on swelling power of different cultivars of Chinese chestnut power.【Method】The contents of protein, fat and starch were determined by Kjeldahl method, Soxhlet extraction method and Anthracene ketone colorimetric method, respectively. The native power, de-fat power and de-protein power of chestnut were obtained by freeze-drying, SoxhLet extraction and alkali liquor precipitation, respectively. Statistical analysis was performed using SPSS version 11.0. 【Result】 Differences of swelling power of chestnut native powder were found among different cultivars and different cultivar groups. Native powder of chestnut from North Cultivar Groups (NCG) had the lowest swelling power compared with other two cultivar groups. De-fat treatment had less influence on swelling power of chestnut powder. However, de-protein treatment increased significantly the swelling power of all cultivars chestnut. There were obvious differences in swelling power and the changes of swelling among cultivars after de-protein, but no differences among different cultivar groups were found. The combination of de-fat and de-protein resulted in significant increases in swelling power and there existed differences among the cultivars. The swelling power of de-protein powder of chestnut followed the sequence: North Cultivar Groups (NCG) > Mid-type Cultivar Groups (MCG) > South Cultivar Groups (SCG). There was a significant difference between NCG and SVG. The differences of content of starch, protein and fat occurred in different cultivar chestnuts, and apparent correlation between starch content and swelling power of chestnut powder were conformed in the meanwhile.【Conclusion】Starch was the main factor influencing swelling power of chestnut powder. Protein and fat in chestnut coordinately influence the swelling power of chestnut powder, which can be modified by de-fat and de-protein treatments. De-protein treatment can remarkably enhance the swelling power while less influence can by caused be de-fat treatment. The effects resulted from de-fat and de-protein were dependent on the cultivars or cultivar groups.