微酸性电解水-复合保鲜剂对冷藏凡纳滨对虾品质及菌群结构影响

Effects of Mixture of Slightly Acidic Electrolytic Water and Compound Preservative on the Quality and Microflora Structure of Litopenaeus vannamei During Refrigerated Storage

【目的】研究微酸性电解水(slightly acidic electrolytic water,SAEW)结合迷迭香提取物(rosemary extract,RE)-柠檬酸(citric acid,CA)复合保鲜剂(RC)处理对冷藏凡纳滨对虾品质与菌群结构的影响。【方法】样品分别经无菌水(CK)、RC、SAEW与SAEW+RC浸渍处理10 min,沥干后(4±1)℃冷藏。每2 d测定其菌落总数(total viable count,TVC)、嗜冷菌数(Psychrophilic bacteria count)、希瓦氏菌数(Shewanella bacteria count)和假单胞菌数(Pseudomonas bacteria count)等微生物与总挥发性盐基氮(total volatile basic nitrogen,TVB-N)、生物胺含量(腐胺与尸胺)等化学指标,结合高通量测序与热图分析其品质与微生物菌群变化。【结果】微酸性电解水-复合保鲜剂处理能延缓凡纳滨对虾贮藏期间各项指标的升高,其在贮藏10 d时的TVC对数值为6.10±0.14,TVB-N值为(16.06±0.34)mg/100g,腐胺质量分数为(4.40±0.06)mg/kg,尸胺质量分数为(6.73±0.06)mg/kg,各指标均显著低于对照组(P<0.05),使凡纳滨对虾的冷藏货架期较对照组延长至少4 d。弧菌(Vibrio)、希瓦氏菌(Shewanella)与嗜冷杆菌(Psychrobacter)为凡纳滨对虾贮藏末期的优势腐败菌。【结论】微酸性电解水结合迷迭香提取物和柠檬酸对希瓦氏菌与嗜冷杆菌有较好抑制作用,对凡纳滨对虾有明显保鲜效果。

【Objective】The effects of slightly acidic electrolyzed water(SAEW)combined with rosemary extract(RE)-citric acid(CA)compound preservatives(RC)treatment on the quality and microflora structure of Pacific white shrimp(Litopenaeus vannamei)during refrigerated storage were studied.【Methods】Samples were impregnated with sterile water(CK),RC,SAEW and SAEW+RC for 10 min respectively,then drained and refrigerated at(4±1)℃.Microbial(total viable count(TVC),psychrophilic bacteria count,shewanella bacteria count and pseudomonas bacteria count)and chemical(total volatile basic nitrogen(TVB-N),biogenic amines contents(putrescine and cadaverine))indexes were measured respectively at 2-day intervals.The quality and microflora changes were analyzed by high-throughput sequencing technique and heatmap.【Results】Slightly acidic electrolyzed water combined with compound preservatives can delay the increase of various indexes of L.vannamei during refrigerated storage.On day 10,the logarithm value of TVC in the sample with SAEW+RC treatment was(6.10±0.14),TVB-N value was(16.06±0.34)mg/100g,the putrescine content was(4.40±0.06)mg/kg and the cadaverine content was(6.73±0.06)mg/kg.All indexes were significantly lower than those in the control group(P<0.05).Compared with the control group,the shelf-life of L.vannamei during refrigerated storage was prolonged for>4 days at least.Vibrio,Shewanella and Psychrobacter were the dominant spoilage bacteria of L.vannamei at the end of storage.【Conclusion】Slightly acidic electrolytic water coupled with rosemary extract and citric acid had a good inhibitory effect on Shewanella and Psychrobacter,and had the obvious preservation effect on L.vannamei.