High molecular-weight water-soluble chitosan coating extends the shelf-life of raw egg during room temperature storage

Abstract Maintaining egg quality during storage is important for shelf-life extension of eggs, particularly in regions where refrigerated storage is limited or unavailable. Although chitosan coatings have shown potential for preserving egg quality, chitosan coatings often require acidic solvents and prolonged dissolution, which may limit their practical application. The effectiveness of high molecular-weight water-soluble chitosan dissolved in amino acid for maintaining egg quality remains unknown. Raw eggs were divided into five treatments: uncoated eggs (control), eggs coated with 1% amino acid solution (0% AMA-CH), and eggs coated with 1%, 2%, or 3% amino acid-chitosan (AMA-CH) solutions. Ten eggs per treatment were evaluated weekly for weight loss, Haugh unit, yolk index, and yolk and albumen pH during eight weeks of storage at 22 ± 2 °C and 55± 5% RH. Statistical significance was determined at p<0.05. AMA-CH coatings reduced weight loss and delayed the deterioration of internal egg quality compared with the control. After six weeks, weight loss was 8.5%, 8.6%, and 9.1% in eggs coated with 1%, 2%, and 3% AMA-CH, respectively, compared with 12% in the control. Higher AMA-CH concentrations maintained higher yolk index values, while 2% AMA-CH maintained the best albumen quality (B Grade up to 7 weeks) based on Haugh unit values. Overall, AMA-CH coatings show potential for extending the shelf life and maintaining the quality of raw eggs under room-temperature storage. The shorter dissolution time of AMA-CH formulation and the absence of unpleasant acidic odors may facilitate practical application, particularly in regions with limited refrigerated storage.