• chitosan-coated egg;
  • Haugh unit;
  • Salmonella enterica Enteritidis;
  • weight loss;
  • yolk index

ABSTRACT:  Effects of the molecular weight and type of chitosans and pH of chitosan solution on antibacterial activity against Salmonella enterica Enteritidis and on internal quality of chitosan-coated eggs were evaluated during 4 wk of storage at 25 °C. Two types of chitosans were studied: α-chitosans with 4 different molecular weights (Mw = 282, 440, 746, and 1110 kDa) and β-chitosan (Mw = 577 kDa). The α-chitosan with 282 kDa exhibited stronger bactericidal effects than did other α- and β-chitosans. The weight loss, Haugh unit, and yolk index values suggested that coating of eggs with α-chitosan with 282 kDa increased the shelf-life of eggs by almost 3 wk at 25 °C compared with noncoated eggs. The pH (4.5, 5.0, and 5.5) of the α-chitosan (282 kDa) solution did not affect the internal quality of chitosan-coated eggs. Therefore, coating of eggs with 282 kDa α-chitosan without pH adjustment (initial pH of 4.5) may offer a protective barrier against contamination of S. Enteritidis while simultaneously preserving the internal quality of eggs.