In recent years, heavy‐metal salts for pickling preserved eggs and the long production period have affected its acceptability and industrialization. In this study, we used the method of short‐term pickling of no‐heavy‐metal salts to obtain gels by alkali‐picked and heat induced. The physicochemical properties, secondary structure and free amino acid composition of egg whites during pickling were determined. Furthermore, the texture and chromatic characters of the preserved egg white gels after heating were analyzed. After 7 days of pickling, the pH and free alkalinity can reach the level of preserved eggs, presenting the value of 11.48 and 184.03 mg/100 g respectively. The α‐helix content decreased from 36.01% to 32.39%. On the other hand, the β‐turns increased from 16.98% to 18.82%, and the Random coils increased from 26.31% to 28.76%. The free sulfhydryl content of preserved egg white increased gradually, whereas the total sulfhydryl content, the Td value, and free amino acid content decreased during the pickling process. The hardness and springiness of the gel remained largely unchanged during the pickling time (5–8 days). The gel's appearance, chromatic, and texture reached the level of traditional preserved egg in a relatively short pickling time, providing a new idea for the rapid picking of preserved egg white gel. The treatment in this study is important for improving the efficiency of industrial production of preserved egg white gels.
Practical applications
Heat treatment is a standard method in food processing, helping improve the texture and quality of products. After heat treatment, the physicochemical properties of the alkali‐pickled eggs can reach the state of traditionally preserved egg whites. Therefore, the method described in this study can help shorten the pickling time of preserved egg white products and provide theoretical support for developing new preserved egg products.
Summary
The colour, texture, water‐holding capacity (WHC) and particle properties of gels were examined to assess the impact of starch (cassava, corn and sweet potato starch) on the attributes of alkali‐heat‐induced gels. The results indicated that the whiteness, hardness and WHC of egg white gels were positively affected by starches. The microstructure of the mixed gel showed increasing reticulation and holes as the starch content increased, which contributed to the stiff structure of the gel. Although the gel made with corn starch had the lowest WHC, the gel made with sweet potato starch had the highest WHC. The average size of the gel particles decreased as a result of the inhibition of starch gelatinisation. Starch causes alterations in the protein secondary structure of egg white gels, primarily causing α‐helix and β‐sheet interconversion. The stiffness of the gels was improved by increasing the quantity of β‐sheet structures. According to the electrophoresis findings, a small amount of sweet potato starch can help prevent ovalbumin from degrading, while having no impact on the ability of the protein to cross‐link.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.