[关键词]
[摘要]
采用湿热法制得了锥栗重结晶淀粉,研究了贮藏条件对其理化特性的影响。结果表明:在4 ℃贮藏时,对重结晶淀粉体外消化动力学参数的影响很显著,能形成更多的抗性淀粉,第14天平均聚合度达到最大,晶型从贮藏0 d的A型,依次转变为第3 d、7 d的V型,第14 d、21 d的B型,相对结晶度变化非常显著;在25 ℃贮藏时对体外消化动力学参数的影响也较大,能形成更多的快速消化淀粉,第3天平均聚合度达到最大,晶型保持A型,相对结晶度变化不明显,仅出现低温熔融区,与4 ℃贮藏时相比,其熔融焓降低较多、熔融峰温度差降低更显著;在4/25 ℃贮藏时,对体外消化动力学参数的影响也很显著,能形成更多的缓慢消化淀粉,前7 d内平均聚合度增加较快,晶型从贮藏0 d的A型依次转变为第3 d的V型、第7 d和第14 d的B型、第21 d的V型,相对结晶度变化较快,高温熔融区的峰值温度和终止温度较之4 ℃贮藏时降低较多。
[Key word]
[Abstract]
Starch from Castanea henryi was recrystallized by heat-moisture treatment; in addition, the effect of different storage conditions on the physical and chemical properties of recrystallized starch was studied. Storage at 4 ℃ was observed to exert a significant influence on the in vitro digestion kinetic parameters of recrystallized starch; in addition, storage at this temperature resulted in the formation of starch with greater resistance, with the average degree of polymerization reaching the maximum limit on the 14th day. The type of crystal showed a gradual change from type A (on day 0) to type V on the 3rd and 7th day, and type B on the 14th and 21st day, with significant alterations in the relative crystallinity. Storage at 25 ℃ also had a substantial effect on the in vitro digestion kinetic parameters, resulting in the formation of starch that could be digested faster. The maximum average degree of polymerization was achieved on day 3; the crystal type from day 0 (type A) was retained over time, and the changes in relative crystallinity were not obvious, excluding the appearance of a low-temperature melting zone. The melting enthalpy of crystallized starch stored at 25 ℃ was substantially reduced compared to that stored at 4 ℃; in addition, the reduction in melting peak temperature was observed to be more prominent. Storage at 4/25 ℃ also had a significant effect on the in vitro digestion kinetic parameters, resulting in the formation of starch that was slowly digested. This resulted in a relatively rapid increase in the average degree of polymerization up to the 7th day. The crystal type was altered from type A on day 0 to type V on the day 3, type B on the 7th and 14th days, and type V on the 21st day. Rapid changes in relative crystallinity were observed. In addition, the peak and conclusion temperatures of the high temperature melting zone decreased by large amounts compared to the 4 ℃ storage condition.
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[基金项目]
国家级大学生创新创业训练计划项目(教高司函[2013]8号);湖南省自然科学基金项目(11JJ6009)