壳聚糖与生姜提取物对冷鲜肉贮藏过程中的保鲜效果

Preservation effect of chitosan and ginger extract on cooled pork during storage

探讨壳聚糖(chitosan,CS)与生姜提取物(ginger extracts,GE)对鲜猪肉冷藏期间保鲜效果的影响。采用乙醇提取法制备GE,测定其总酚、总黄酮含量及抗氧化活性。通过理化指标(汁液损失率、pH值、挥发性盐基氮、色差)和微生物指标(菌落总数、大肠菌群、乳酸菌、假单胞菌)对CS和GE处理的肉样的品质进行综合评价。结果表明,GE总酚含量为1.35 mg/mL,总黄酮含量为1.98 mg/mL。GE对ABTS阳离子自由基的清除能力强于DPPH自由基,并呈浓度依耐型。当GE质量浓度为7.5 mg/mL,DPPH自由基清除率达89.05%;GE质量浓度为0.1375 mg/mL,对ABTS阳离子自由基的清除率高达99.51%。CS和GE均能延缓冷鲜肉的腐败变质,延长其货架期。GE能更显著地减少冷鲜肉的汁液损失和延缓色度变化。然而,CS在延缓pH值升高,抑制挥发性盐基氮的产生和腐败微生物的生长繁殖方面效果更加显著。CS和GE处理能有效地保持冷鲜肉贮藏过程中的品质,延长冷鲜肉的货架期至9 d,GE可作为天然的抗氧化剂和抑菌剂在食品保鲜中应用。

This study aimed to investigate the effect of chitosan(CS)and ginger extracts(GE)on preserving the quality of cooled pork during cold storage.The GE was extracted by using ethanol as solvent.The total phenol,total flavonoid content,and antioxidant activity of GE were assessed.The quality of cooled pork treated with CS and GE were comprehensively evaluated through physicochemical properties(juice loss rate,pH value,total volatile basic nitrogen,and color difference)and microbiological indicators(the total bacterial count,coliforms,lactic acid bacteria,and Pseudomonas).Results showed that the total phenol content of GE was 1.35 mg/mL,and the total flavonoid content was 1.98 mg/mL.The ABTS cationic radical scavenging ability of GE was stronger than DPPH free radical scavenging ability and showed concentration-dependent.When the GE concentration was 7.5 mg/mL,the DPPH free radical scavenging rate reached 89.05%.When the GE concentration was 0.1375 mg/mL,the ABTS cationic radical scavenging rate was 99.51%.Both CS and GE could delay the spoilage of cooled pork and prolong its shelf life.Compared to CS,GE could more significantly reduce the juice loss and delay the color change of cooled pork.However,CS was more effective in delaying the increase of pH value and inhibiting the production of total volatile basic nitrogen and the growth of spoilage microorganisms.The above results indicated that CS and GE treatments could effectively maintain the quality of cooled pork during storage and extent their shelf life to 9 days.GE can be used as a natural antioxidant and bacteriostatic agent in food preservation.