Dipartimento di Scienza degli Alimenti, Università degli Studi di Napoli Federico II, Via Università 100, 80055 Portici, Italy.
Int J Food Microbiol. 2012 Sep 3;158(3):186-94. doi: 10.1016/j.ijfoodmicro.2012.07.011. Epub 2012 Jul 17.
An antimicrobial polyethylene (PE) film was obtained by coating a nisin-based antimicrobial solution. PE sheets were coated on both sides and were used for the packaging of beefsteaks to be stored in air or modified atmosphere packaging (MAP, 60% O₂-40% CO₂). Microbial populations, species diversity, headspace volatile organic compounds, colour and sensory properties were monitored after 0, 1, 7 and 12 days of storage at 4 °C. The viable counts showed that there was an effect of MAP and antimicrobial film on the development of all the spoilage associated microbial populations. Carnobacterium spp., Brochothrix thermosphacta, Pseudomonas fragi and Rhanella aquatilis were found in most of the samples. C. maltaromaticum was identified in MRS bulk cells from samples stored in air as well as MAP. Quantitative data of headspace-SPME-GC/MS analysis showed that during storage the production of volatile organic compounds (VOCs) was affected by the use of the treated film and the MAP storage. Compounds such as phenylethylalcohol, nonanal, decanal and ethylbutanoate were produced only from 7 to 12 day of storage and only in the samples stored in air. In agreement with the microbiological and VOCs data, the meat stored in active packaging scored the best rankings in the sensory evaluation. Principal component analysis of microbial, sensory and instrumental data showed that beefsteaks stored with the combination of MAP and active packaging for 12 days at 4 °C differed from the other samples that were more associated to high microbial loads, VOCs concentration and meat off odour perception. In conclusion, the antimicrobial sheets in combination with MAP storage at 4 °C were effective for the storage of beefsteaks by retarding the growth of spoilage bacteria, determining lower concentration of VOCs and keeping acceptable levels of colour and other sensory parameters for more than 10 days.
一种基于乳链菌肽的抗菌溶液涂覆在聚乙烯（PE）薄膜上，得到一种抗菌聚乙烯薄膜。将 PE 薄膜的两面进行涂层处理，用于包装牛排，在空气或改良气氛包装（MAP，60% O₂-40% CO₂）中储存。在 4°C 下储存 0、1、7 和 12 天后，监测微生物种群、物种多样性、顶空挥发性有机化合物、颜色和感官特性。活细菌计数表明，MAP 和抗菌薄膜对所有与变质相关的微生物种群的发展都有影响。在大多数样本中发现了乳球菌属、热死环丝菌、脆弱拟杆菌和水生栖热菌。在空气和 MAP 储存的样品中，从 MRS 块状细胞中鉴定出了 C. maltaromaticum。顶空 - SPME-GC/MS 分析的定量数据表明，在储存过程中，挥发性有机化合物（VOCs）的产生受到处理薄膜和 MAP 储存的影响。只有在空气储存的样品中，从储存的第 7 天到第 12 天，才会产生苯乙醇、壬醛、癸醛和丁酸乙酯等化合物。与微生物和 VOCs 数据一致的是，在活性包装中储存的肉在感官评价中得分最高。微生物、感官和仪器数据的主成分分析表明，在 4°C 下结合 MAP 和活性包装储存 12 天的牛排与其他样品不同，这些样品与高微生物负荷、VOCs 浓度和肉异味感知更相关。总之，抗菌薄膜与 4°C 下的 MAP 储存相结合，通过延缓腐败细菌的生长，确定较低的 VOCs 浓度，并保持可接受的颜色和其他感官参数水平超过 10 天，可有效用于牛排的储存。
