College of Food Science and Technology, Nanjing Agricultural University, Key Laboratory of Food Processing and Quality Control of Ministry of Agriculture, Nanjing 210095, People's Republic of China.
Department of Nutrition and Food Sciences, University of Maryland, College Park, Maryland 20742, USA.
J Food Prot. 2014 Mar;77(3):459-65. doi: 10.4315/0362-028X.JFP-13-359.
The food-based fermentate (FBF) from Lactobacillus acidophilus NX2-6 has a broad-spectrum antibacterial activity but has not previously been reported as a food preservative. Experiments were conducted to assess its application as a preservative in pork patties. The effect of freeze-dried FBF on the microbiological parameters, physicochemical changes, and sensory evaluations of chilled pork patties stored for 15 days at 4°C was investigated. The five treatments evaluated included a control (meat only), nisin (meat plus 0.5% nisin), L.1 (meat plus 2% freeze-dried FBF), L.2 (meat plus 4% freeze-dried FBF), and L.3 (meat plus 8% freeze-dried FBF). The results showed that freeze-dried FBF could significantly (P < 0.05) inhibit aerobic bacteria, coliforms, Pseudomonas spp., and lactic acid bacteria, with the lowest microbial counts observed in L.3. The addition of freeze-dried FBF resulted in concentration-dependent decreases in total volatile basic nitrogen values and pH values but increases in lipid oxidation and color instability. Based on the criteria regarding microbiological and physicochemical parameters, the shelf life was 9 to 12 days for L.1, 12 to 15 days for L.2, and over 15 days for L.3, while the shelf-lives of the control and nisin treatments were 3 to 6 days, indicating that freeze-dried FBF could extend the shelf life by more than 3 days. Although the shelf life of L.1 was shorter than those of L.2 and L.3, the appearance of L.1 was much better than those of L.2 and L.3. Overall, treatment with 4 or 8% freeze-dried FBF could be improved if color and lipid oxidation could be improved by appropriate stabilizers, and a lower concentration (2%) of freeze-dried FBF has great potential as a natural and safe preservative in chilled pork patties.
嗜酸乳杆菌 NX2-6 的发酵物（FBF）具有广谱抗菌活性，但尚未被报道为食品防腐剂。本实验旨在评估其作为一种防腐剂在冷藏猪肉饼中的应用。研究了冷冻干燥 FBF 对冷藏猪肉饼在 4°C 下储存 15 天期间微生物参数、理化变化和感官评价的影响。评估了五种处理方法，包括对照（仅肉）、乳链菌肽（肉加 0.5%乳链菌肽）、L.1（肉加 2%冷冻干燥 FBF）、L.2（肉加 4%冷冻干燥 FBF）和 L.3（肉加 8%冷冻干燥 FBF）。结果表明，冷冻干燥 FBF 能显著（P<0.05）抑制需氧菌、大肠菌群、假单胞菌和乳酸菌，L.3 的微生物数量最低。添加冷冻干燥 FBF 会导致总挥发性碱性氮值和 pH 值呈浓度依赖性下降，脂质氧化和颜色稳定性增加。根据微生物和理化参数的标准，L.1 的保质期为 9 至 12 天，L.2 为 12 至 15 天，L.3 超过 15 天，而对照和乳链菌肽处理的保质期为 3 至 6 天，表明冷冻干燥 FBF 可将保质期延长 3 天以上。虽然 L.1 的保质期短于 L.2 和 L.3，但 L.1 的外观明显好于 L.2 和 L.3。总体而言，如果能通过适当的稳定剂改善颜色和脂质氧化，添加 4%或 8%的冷冻干燥 FBF 可以得到改善，而 2%的较低浓度的冷冻干燥 FBF 具有作为冷藏猪肉饼天然安全防腐剂的巨大潜力。
