Innovative foam drying technique for salted egg yolk powder production.

Background: The powderization of salted egg yolks can circumvent the gelatinization issues that occur during frozen storage. In this study, salted egg yolk powder (SEYP) was prepared using microwave-assisted foam drying (MFD) technology.

Results: The results show that, compared to traditional microwave drying and hot-air drying, the SEYP prepared by MFD exhibits a bright color and a loose structure, and shows significant improvements in emulsifying properties, lecithin retention rate and antioxidant activity (P < 0.05). The optimal microwave power for MFD of SEYP, established through principal component analysis, is 350 W, with no requirement for a cooking treatment of the salted egg yolks. Gas chromatography-mass spectrometry identified n-butanol, hexanal, nonanal, ethyl acetate, d-limonene and isopentanal as the primary volatile compounds in SEYP, contributing to its unique flavor profile. Furthermore, the SEYP prepared using MFD at 350 W also shows a reduction of 18.88% in the content of bitter-tasting amino acids compared with microwave drying.

Conclusion: In summary, MFD technology is a green and efficient drying method suitable for the preparation of flavor-type SEYP. © 2024 Society of Chemical Industry.