关键词: 柠檬精油纳米乳液, 可食用涂膜液, 涂膜保鲜, 货架期, 卤鸭脖

Abstract: The objective of this study was to assess the effect of an edible coating containing lemon essential oil emulsion on preserving the quality of refrigerated pot-stewed duck neck. The lemon essential oil emulsion and nanoemulsion coatings were prepared by high-speed shearing and microfluidization, respectively and their effects on physicochemical and microbial properties of refrigerated pot-stewed duck neck were comparatively studied. The results showed that the nanoemulsion had lower particle size, whiteness index and viscosity when compared with the emulsion, and the appearance was translucent. The quality of pot-stewed duck neck in the blank group declined with storage period, and complete spoilage occurred on the 12th day. At this time, the thiobarbituric acid reactive substance (TBARS) value and total volatile basic nitrogen (TVB-N) content were 3.23 mg/kg and 33.6 mg/100 g, respectively, and the total bacterial count increased to 5.79 (lg(CFU/g)). The lemon essential oil nanoemulsion had better preservation effect compared with the emulsion and sodium alginate; the TBARS value and TVB-N content of the nanoemulsion coating group were only 2.80 mg/kg and 20.76 mg/100 g, respectively, and the total bacterial count was 4.85 (lg(CFU/g)) on the 12th day. In addition, there was no significant difference in color difference between the lemon essential oil emulsion group and the blank group. The above results showed that the lemon essential oil emulsion edible coating can significantly preserve the quality of refrigerated pot-stewed duck neck, but its effect was inferior to that of the essential oil nanoemulsion coating, which could extend the shelf life of the product from 8 to 12 days.

Key words: lemon essential oil nanoemulsion, edible coating, coating preservation, shelf life, pot-stewed duck neck