Effect of sodium nitrite in LDPE/PET-based active film on vacuum-packaged pork quality

Abstract

In this study, based on the development of low-density polyethylene/polyethylene terephthalate (LDPE/PET) active packaging film with color and quality protection for vacuum-packaged pork, a relationship model between the amount of sodium nitrite (SN) added in the active film and the ratio of pork chromaticity was established to guide the preparation of the active film for vacuum-packaged pork. The active film of LDPE/PET incorporating SN was developed, characterized, and applied to vacuum-packaged pork. Compared with the LDPE/PET film without SN, the active film containing 0.5 wt% or more SN could effectively improve pork color to make it appear bright-red, and extend its shelf life to 15 −18 d due to a reduction in total volatile base nitrogen contents and microbial proliferation during storage at 4 °C. Based on the above, a color prediction model of the chromaticity ratio S* was established to predict the color protection effect of the active film containing different SN content on pork. The relative error between the predicted and measured values of S* was 0.09 %−10.21 %, indicating the effectiveness of the model. Therefore, the developed active film has a positive potential for application in pork preservation, and the established model can guide the development of LDPE/PET-based active films incorporating SN and their application in vacuum-packaged pork.