中低烘烤温度对花生中油脂品质、蛋白质性质及内源性蛋白酶活性的影响Effects of low and medium roasting temperatures on oil quality, protein properties and endogenous protease activity in peanut

Abstract

为探究中低烘烤温度对花生品质的影响，以花生为原料，研究烘烤温度（50～140 ℃）对花生中油脂的酸值和过氧化值、蛋白质提取率、蛋白质分散指数（PDI）及内源性蛋白酶活性影响。结果表明：花生油的酸值总体上随烘烤温度的升高而升高，而过氧化值总体上呈先升高后降低的趋势，但均未超过国家标准限量；适度烘烤可显著提高蛋白质提取率，最高可达98.78%（120 ℃），而过度烘烤则降低蛋白质提取率；PDI随烘烤温度的升高呈先上升后下降的趋势，在90 ℃时PDI最高（98.73%），烘烤温度在110 ℃以内时，PDI均在95%以上；内源性蛋白酶对花生蛋白的水解能力随着烘烤温度的升高呈先升后降趋势，烘烤温度小于或等于110 ℃时，有利于花生蛋白被内源性蛋白酶水解，其中70～80 ℃烘烤时花生蛋白最易被水解，烘烤温度为120～140 ℃时，则不利于花生蛋白被内源性蛋白酶水解，140 ℃时内源性蛋白酶仍具一定活性。综上，建议选择110 ℃作为花生的烘烤温度，以有利于花生中油脂和蛋白质的综合利用。 In order to investigate the effects of low and medium roasting temperatures on the quality of peanut, the effects of roasting temperature (50-140 ℃)on the acid value and peroxide value of oil, protein extraction rate, protein dispersion index (PDI) and endogenous protease activity in peanut were examined. The results showed that the acid value of peanut oil generally increased with roasting temperature increasing, while the peroxide value generally increased firstly and then decreased, but both were within the national standard. The protein extraction rate was significantly improved with a moderate roasting, up to 98.78% at 120 ℃, and reduced with an excessive roasting. The PDI showed a trend of increasing first and then decreasing with the increase of roasting temperature. The highest PDI was 9873% obtained at 90 ℃, and the PDI was over 95% within 110 ℃ roasting temperature. The degree of hydrolysis of peanut protein by endogenous protease increased at first and then decreased with the increase of roasting temperature. When the roasting temperature was less than or equal to 110 ℃, roasting was conducive to the hydrolysis of peanut protein by endogenous protease, and peanut protein was most easily hydrolyzed at 70-80 ℃. When the roasting temperature was 120-140 ℃, roasting was not conducive to the hydrolysis of peanut protein by endogenous protease. Endogenous protease still had certain activity at 140 ℃.In conclusion, it is recommended to select 110 ℃ as the roasting temperature for peanut in order to facilitate the comprehensive use of oil and protein in peanut.

Keywords

• 烘烤温度 花生 花生油 蛋白质 内源性蛋白酶
• roasting temperature peanut peanut oil protein endogenous protease