瞬时高压处理对α-淀粉酶活性的影响

Effect of Instantaneous High Pressure Process on α-amylase Activity

研究了不同条件下瞬时高压处理对-α淀粉酶活性的影响。结果表明:瞬时高压作用对α-淀粉酶具有有效的钝化作用,在pH 6时,25℃、35℃、45℃下分别处理1次,80￣120 MPa时α-淀粉酶活性下降较慢,120 MPa后活性下降变快;提高进料温度,可以增强瞬时高压对-α淀粉酶的钝化效果。pH 6、25℃时,在100 MPa、120 MPa和140 MPa下分别对-α淀粉酶处理3次,在相同的作用压力下,-α淀粉酶活性随处理次数的增加呈下降趋势;α-淀粉酶活性降低幅度随处理次数的增加而变小。常压下-α淀粉酶在pH值5.0～8.0时较为稳定,pH值低于4时严重失活;120 MPa下,α-淀粉酶活性较常压下低;活性下降幅度在强酸时更大,其次为强碱,pH 6时最小。

This paper studied the effect of Instantaneous High Pressure （IHP） treatment on α-amylase activity under different conditions. The results demonstrated that： IHP effectively reduce the activity of α-amylase. If α- amylase was treated separately at 25 ℃ ,35 ℃ and 45 ℃ with pH 6, its activity decrease was slow for treating presstare at 80-120 MPa and quickened surpassing 120 MPa.Increasing feed-in temperature can augment the reduction of activity of α-amylase being treated by IHP. At pH 6.0 and 25 ℃, α-amylase was processed 3 times under 100,120 and 140 MPa respectively, and the results showed that under the same pressure, the activity of α- amylase decreased with processed times, and the decrease extent also became smaller with processed times. Under common atmospheric pressure, α-amylase was fairly stable when pH was between 5.0-8.0, and its stability is tremendously undermined below pH 4; When the process pressure was 120 MPa, the activity of α-amylase was lower than that under atmospheric pressure, and furthermore the activity decrease was more obvious under strong acidic condition, while the decrease under strong alkaline condition followed with the smallest decrease being witnessed at pH 6.