不同包装对甜椒贮后货架期挥发性物质及理化品质的影响

Effects of Different Packaging Methods on Volatile Components and Physicochemical Qualities of Sweet Peppers during Shelf-Life after Storage

以甜椒鲜果为原料,运用电子鼻结合顶空固相微萃取-气相色谱质谱(head space solid-phase microextraction and gas chromatography mass spectrometry,HS-SPME-GC-MS)联用技术,对甜椒10℃冷藏15 d后进行常温贮后货架期间挥发性成分进行测定,探究不同包装(无包装对照、微孔袋、20μm聚乙烯袋包装)对其挥发性物质的影响,通过测定果实质量损失率、VC含量、糖酸比等指标分析不同包装对甜椒理化品质的影响。结果表明,电子鼻能够区分不同包装方式、不同贮后货架期的甜椒整体挥发性物质;GC-MS分析得出,甜椒的挥发性成分主要为酯类和醇类物质,且随着贮后货架时间的延长,酯类物质不断减少,而醇类物质则不断上升,对照、微孔袋、20μm聚乙烯袋3组酯类相对含量分别下降了47.33%、23.43%和51.39%,醇类相对含量分别上升了68.73%、56.80%和72.96%,说明微孔袋包装可以有效延缓酯类物质的损失以及延缓醇类物质的增加,有效改善甜椒常温货架期间的香气成分,其保鲜作用优于对照和20μm聚乙烯袋组;相同贮后货架期下微孔袋组的VC含量和糖酸比均最高,微孔袋、20μm聚乙烯袋包装组之间质量损失率差异不显著(P>0.05),但明显小于对照组(P<0.05),说明微孔袋包装对甜椒贮后货架期理化品质的保鲜作用优于对照和20μm聚乙烯袋组。

The physicochemical qualities of sweet peppers with different packaging treatments during shelf-life at normal temperature after storage at 10 ℃ for 15 days were comparatively evaluated in term of weight loss, vitamin C content and sugar/acid ratio. Besides, the volatile components were also analyzed using head space solid-phase microextraction and gas chromatography mass spectrometry（HS-SPME-GC-MS） and electronic nose technology. The aim of these experiments was to investigate the effects of different packaging materials（no packaging, microporous bag, and 20 μm thick polyethylene（PE） bag） on the volatile components and physicochemical qualities of sweet peppers during post-cold storage shelf-life. The results showed that electronic nose could distinguish the whole volatile components of sweet peppers contained in different packaging bags during different shelf-life periods after storage,which were mainly esters and alcohols. The contents of volatile esters of sweet peppers decreased during shelf-life while alcohols increased. The relative contents of esters in the control, microporous bag, and PE bag groups decreased by 47.33%, 23.43% and 51.39%,whereas alcohols increased by 68.73%, 56.80% and 72.96%, respectively. These results showed that microporous bags most significantly retarded the decrease of esters and the increase of alcohols and effectively improved the aroma components of sweet pepper during shelflife after storage, having better preservation effect than the control and PE group. The microporous bag treatment had the highest levels of vitamin C and sugar/acid ratio. No significant difference in weight loss rate was seen between the microporous bag and PE bag groups（P 〉0.05）, but both were significantly lower than the control group（P〈 0.05）. Overall, microporous bags could most effectively preserve the physicochemical qualities of sweet peppers during shelflife after storage.