Comparative study on Tianjin and Baiyangdian preserved eggs pickled by vacuum technology

Abstract

In this study, the Tianjin and Baiyangdian duck eggs were used to pickle the preserved eggs by a novel technology—vacuum technology. The curing time of vacuum technology was reduced by three times compared with the traditional method. The weight gain rates of preserved eggs pickled by the traditional method first increased and then decreased, while the preserved eggs pickled by vacuum technology were weightless at the first day. With the prolonging of curing time, the pH of egg yolks of preserved eggs showed a rising trend, no matter pickled by traditional method or vacuum technology. The cholesterol contents of Tianjin and Baiyangdian preserved eggs reduced 16.22% and 29.59% compared to the duck eggs. Besides, there were 15 kinds of fatty acid were detected in Tianjin and Baiyangdian duck eggs and preserved eggs. The SEM images showed that the eggshells of Tianjin and Baiyangdian duck eggs were multilayered structures. Practical applications Vacuum technology is applied in many products, but this is the first time that it has been used to pickle preserved eggs. The traditional curing time of preserved eggs was 3–8 weeks at room temperature, while the vacuum technology could greatly shorten the pickling time. Therefore, vacuum technology had broad application prospect and important practical value.