苹果渣乙醇提取物抗菌活性及防腐作用研究

为提高苹果渣资源利用率,探究苹果渣乙醇提取物的抗菌活性和防腐性能,该文采用微波辅助提取法制取苹果渣乙醇提取物,用抑菌圈实验测定其抗菌活性,并研究了其防腐作用。结果表明:(1)苹果渣乙醇提取物对酵母菌抑制作用不明显(抑菌圈直径<1 mm),对金黄色葡萄球菌和大肠杆菌的抑菌作用较明显(抑菌圈直径为6～9 mm),最佳抑菌浓度为4.0 g·L^-1。(2)pH值和盐浓度对其抑菌效果有影响,pH值为6～7,盐浓度为5.0 g·L^-1,抑菌效果最好。(3)对百香果有较好的保鲜防腐效果,最佳使用浓度为0.2%。在该浓度下贮藏后的百香果腐烂率为6.7%(对照组为67%),失重率为5.5%(对照组为36.3%),可溶性固形物、总酸含量均与贮藏前差异不显著(P> 0.05)(对照组P< 0.05),且果实较饱满,硬度较高,鲜艳有光泽,酸甜适中。综上所述,苹果渣乙醇提取物对大肠杆菌和金黄色葡萄球菌具有良好的抑制作用,对百香果的保鲜防腐效果佳,可应用到天然食品的保鲜防腐。

Antibacterial activity and antiseptic effect of ethanol extract from apple pomace

In order to improve the utilization of apple pomace resources, verify the antibacterial activity and antiseptic properties of the ethanol extract of apple pomace, the antibacterial activity of extract from apple pomace were determined by the inhibition zone test. In addition, the antibacterial effect of the extract under different pH and salt concentration had been studied. At the same time, the ethanol extract of apple pomace was applied to the preservation of Passiflora edulia, using sensory scores and various physical and chemical indicators(Vc, soluble solids, total acid, solid acid ratio)as the basis to investigate the antiseptic effect of the extract. The results were as follows:(1)The ethanol extract of apple pomace had no obvious inhibitory effect on yeasts(diameter of inhibition zone <1 mm), but it had obvious inhibitory effect on Staphylococcus aureus and Escherichia coli(diameter of inhibition zone was 6-9 mm).(2)The best inhibitory concentration for these strains was 4.0 g·L^-1. In addition, when the antibacterial effect of the extract was optimal, the pH was 6-7 and the salt concentration was 5.0 g·L^-1.(3)The optimal concentration for Passiflora edulia was 0.2%, and the rot rate after storage at this concentration was only 6.7%(control group was 67%), and the weight loss rate was 5.5%(control group was 36.3%). The soluble solids and total acid content were not significantly different from those before storage(P>0.05)(control group P<0.05). And most of the fruits were plump, firm, bright and shiny, moderately sweet and sour. The antibacterial extract of apple pomace has antibacterial activity and significant antiseptic effect, and provides a theoretical basis for the development and utilization of apple pomace resources.