Goulas A E, Chouliara I, Nessi E, Kontominas M G, Savvaidis I N
Laboratory of Food Chemistry and Microbiology, Department of Chemistry, University of Ioannina, Ioannina, Greece.
J Appl Microbiol. 2005;98(3):752-60. doi: 10.1111/j.1365-2672.2004.02512.x.
To determine the microbiological, biochemical and sensory changes of mussels during storage under aerobic, vacuum packaging (VP) and modified atmosphere packaging (MAP) conditions at 4 degrees C, and to determine shelf-life of mussels under the same packaging conditions using the above assessment parameters.
Aqua-cultured mussels (Mytilus galloprovincialis) were obtained from a local culture farm, packaged aerobically under VP and MAP (50%/50% CO2/N2: M1, 80%/20% CO2/N2: M2, 40%/30%/30% CO2/N2/O2: M3), and stored at 4 degrees C. Quality evaluation was carried out using microbiological, chemical and sensory analyses. Microbiological results revealed that the M2 and VP delayed microbial growth compared with that of air-packaged samples. The effect was more pronounced for total viable count (TVC), Pseudomonas spp., lactic acid bacteria (LAB) and H2S-producing bacteria. TVC was reduced by 0.9-1.0, Pseudomonas spp. by 0.7-0.8, LAB by 1.0-2.2, H2S-producing bacteria by 0.7-1.2. Enterobacteriaceae were not significantly affected by MAP conditions. Of the chemical indices determined, the total volatile basic nitrogen and trimethylamine nitrogen values remained lower than the proposed acceptability limits of 35 mg N 100 g(-1) and 12 mg N 100 g(-1), respectively, after 15 days of storage. Both the VP and air-packaged mussel samples exceeded these limits. The thiobarbituric acid value of all MAP and VP mussels remained lower than the proposed acceptability limit of 1 mg malondialdehyde kg(-1). The air-packaged samples exceeded this limit. All samples retained desirable sensory characteristics during the first 8 days of storage.
Based on odour and taste evaluation, the M1 and M3 samples remained acceptable until ca day 11-12, the M2 samples remained acceptable until ca day 14-15 days while the VP and air-packaged mussel samples remained acceptable until ca days 10-11 and 8-9 of storage respectively. Based primarily on sensory, but also on biochemical and microbiological parameters determined, M2 gas mixture was the most effective for mussel preservation achieving a shelf-life of ca 14-15 days.
MAP (M2) can be used to increase the shelf-life of refrigerated mussels. A shelf-life extension of refrigerated mussels by ca 5-6 days under MAP may be obtained.
确定贻贝在4℃有氧、真空包装（VP）和改良气氛包装（MAP）条件下储存期间的微生物、生化和感官变化，并使用上述评估参数确定相同包装条件下贻贝的货架期。
从当地养殖场获取养殖贻贝（地中海贻贝），分别进行有氧包装、VP包装和MAP包装（50%/50% CO₂/N₂：M1、80%/20% CO₂/N₂：M2、40%/30%/30% CO₂/N₂/O₂：M3），并在4℃下储存。通过微生物、化学和感官分析进行质量评估。微生物学结果表明，与空气包装样品相比，M2和VP包装延缓了微生物生长。对总活菌数（TVC）、假单胞菌属、乳酸菌（LAB）和产H₂S细菌的影响更为明显。TVC减少了0.9 - 1.0，假单胞菌属减少了0.7 - 0.8，LAB减少了1.0 - 2.2，产H₂S细菌减少了0.7 - 1.2。肠杆菌科不受MAP条件的显著影响。在所测定的化学指标中，储存15天后，总挥发性盐基氮和三甲胺氮值分别保持低于建议的可接受限值35 mg N 100 g⁻¹和12 mg N 100 g⁻¹。VP包装和空气包装的贻贝样品超过了这些限值。所有MAP和VP包装的贻贝的硫代巴比妥酸值均低于建议的可接受限值1 mg丙二醛 kg⁻¹。空气包装的样品超过了该限值。所有样品在储存的前8天保持了良好的感官特性。
基于气味和味道评估，M1和M3样品在大约第11 - 12天之前仍可接受，M2样品在大约第14 - 15天之前仍可接受，而VP包装和空气包装的贻贝样品分别在大约第10 - 11天和第8 - 9天之前仍可接受。主要基于感官，同时也基于所测定的生化和微生物参数，M2气体混合物对贻贝保存最有效，货架期约为14 - 15天。
MAP（M2）可用于延长冷藏贻贝的货架期。在MAP条件下，冷藏贻贝的货架期可延长约5 - 6天。
