[目的]探究香蕉茎秆汁液发酵产品的功效成分及抗氧化能力,为香蕉茎秆汁液的功能性产品开发利用提供理论支撑.[方法]以香蕉茎秆汁液为原料,添加不同菌剂(K1和开菲尔)进行发酵,分析不同香蕉茎秆汁液含量(100％、50％)发酵产品(乳酸饮料KF100和KF50、酒K100和K50)的功效成分(多酚、单宁、总黄酮)、抗氧化能力(DPPH自由基清除能力、抑制羟自由基能力、抗超氧阴离子自由基能力、金属螯合率)和亚硝酸盐含量的差异,并基于主成分分析法,对香蕉茎秆汁液发酵产品的抗氧化能力进行评价.[结果]香蕉茎秆汁液发酵产品的多酚和单宁含量均高于未发酵香蕉茎秆汁液的多酚(3.05 mg/g)和单宁(37.9 mg/kg)含量,总黄酮均未检出.不同香蕉茎秆汁液含量发酵产品相比,KF100的多酚和单宁含量分别较KF50高24.7％和10.3％,K100的多酚和单宁含量分别较K50高18.7％和32.2％.同香蕉茎秆汁液含量发酵产品相比,KF50和KF100的多酚含量分别较K50和K100低16.3％和12.0％,其单宁含量分别较K50和K100高87.5％和56.4％.香蕉茎秆汁液发酵酒的DPPH自由基清除能力、抑制羟自由基能力和抗超氧阴离子自由基能力强于发酵乳酸饮料,而KF100的金属螯合率最高.主成分分析结果显示,K50的抗氧化活性指标综合评价得分最高.此外,KF100的亚硝酸盐含量最高,达2.3μmol/L,其余3组的亚硝酸盐含量均低于0.5μmol/L.[结论]香蕉茎秆汁液发酵产品具有一定的自由基清除能力和较高的金属螯合作用,其中发酵酒K50抗氧化综合评价排名第1,该结果可为进一步开发香蕉茎秆汁液发酵保健产品提供参考.

In order to evaluate the antioxidant capacity of the new variety GC30 processed bananas, develop their functional products and broaden the banana industry chain, five representative banana varieties including GC02 Tianbaogao bananas, GC07 chicken bananas, GC09 powder bananas, GC25 big bananas and GC30 processed bananas were used to study. Specifically, this paper was to analyze the total phenol content and antioxidant capacities of banana peel, pulp and fruit with different varieties and maturity, as well as to statistically analyze antioxidant capacities of different banana varieties and maturity using principal component analysis. The results showed that banana peel had the highest phenol content (P<0.01), and the phenol content of banana peel, pulp and fruit at grade-7 maturity were not significantly different from that at grade-1 maturity. However, the phenol content in banana peel of different varieties was significantly different (P<0.05). In particular, GC30 banana peel at grade-7 maturity had the highest phenol content compared with the other banana varieties. Additionally, the DPPH, superoxide anion and hydroxyl free radical scavenging activities had no significantly differences among banana peel, fruit and pulp (P>0.05). The scavenging activities on DPPH, superoxide anion and hydroxyl free radicals of banana peel, pulp and fruit at grade-7 maturity was significantly higher than that at grade-1 maturity (P<0.01). The metal chelation rate of banana peel was significantly higher than that of banana fruit and pulp (P<0.01), while there was no significant effect on the metal chelation rate of banana peel, pulp and fruit between variety and maturity (P>0.05). Moreover, the antioxidant activities of banana fruit, pulp and peel with different varieties at grade-7 maturity were better than those of fruit, pulp and peel at grade-1 maturity. The GC30 banana peel at grade-7 maturity had the strongest antioxidant properties in the comprehensive evaluation of antioxidants. The findings of this research can provide a theoretical basis for the breeding, processing and application of banana varieties, and promote the commercial value of banana.

探讨了短波紫外线(UV-C)处理对鲜切胡萝卜低温条件下贮藏效果的影响,为鲜切胡萝卜的贮运保鲜提供技术指导.将鲜切胡萝卜通过不同剂量UV-C(1kJ/m2、2kJ/m2、3kJ/m2)辐射后,测定在(4±1)℃下贮藏,测定不同阶段鲜切胡萝卜的各项指标的变化情况.结果显示,用不同剂量的UV-C照射处理,对于鲜切胡萝卜的贮藏期品质影响不同.2KJ/m2 UV-C辐射处理可降低鲜切胡萝卜的呼吸强度、失重率、水分损失,抑制鲜切胡萝卜菌落总数的增长,延缓鲜切胡萝卜的类胡萝卜素、抗坏血酸等营养成分的分解,减少亚硝酸盐在鲜切胡萝卜中的积累;同时UV-C辐射延缓了鲜切胡萝卜中可滴定酸和可溶性固形物的消耗和白化现象的发生.结果表明2KJ/m2 UV-C处理可以有效地延缓鲜切胡萝卜衰老进程,延长产品货架期.