Study on Bacteriostasis of Purple Potato Anthocyanin and Its Fresh-keeping Effect on Strawberry

In order to study the bacteriostasis of purple potato anthocyanin and its effect on strawberry fresh-keeping, the bacteriostasis of purple potato anthocyanin to Escherichia coli, Staphylococcus aureus, Penicillium and yeast, the lowest bacteriostasis concentration and the bacteriostasis of purple potato anthocyanin to potassium sorbate, ethylparaben were analyzed; the effects of purple potato anthocyanin on the weight loss rate, spoilage rate, soluble solid content and total number of colony of strawberry stored at room temperature were determined. The results showed that the antibacterial ability of purple potato anthocyanin was Staphylococcus aureus>E.coli>Penicillium>yeast; the minimum inhibitory concentrations for the four bacterias were 5.625, 11.25, 22.5 and 45 mg/mL, respectively. The weight loss and spoilage rate of strawberries in the 25 mg/mL purple potato anthocyanin+0.5 μg/mL ethylparaben treatment group were significantly lower than those of the control CK(P<0.05), and the soluble solid content was significantly higher than that of the control CK(P<0.05), the total number of colonies was extremely significantly lower than the control CK(P<0.0001). The fresh-keeping ability was ethylparaben+anthocyanins>ethylparaben>anthocyanins>control. In summary, the purple potato anthocyanin had certain antibacterial and fresh-keeping effects, but the effect was worse than that of ethylparaben, and the combination with it had the best effect.