Gel properties of salty liquid whole egg as affected by preheat treatment

Junhua Li; Chenying Wang; Luping Gu; Yujie Su; Cuihua Chang; Yanjun Yang

doi:10.1007/s13197-019-04119-4

Gel properties of salty liquid whole egg as affected by preheat treatment

J Food Sci Technol. 2020 Mar;57(3):877-885. doi: 10.1007/s13197-019-04119-4. Epub 2019 Oct 3.

Authors

Junhua Li^#^{1

2}, Chenying Wang^#^{1

2}, Luping Gu^{1

2}, Yujie Su^{1

2}, Cuihua Chang^{1

2}, Yanjun Yang^{1

2}

Affiliations

¹ 1State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China.
² 2School of Food Science and Technology, Jiangnan University, Wuxi, 214122 Jiangsu China.

^# Contributed equally.

Abstract

Heat treatment is an indispensable processing step of seasoned liquid egg. The effects of preheat treatment (60-75 °C) on gel properties of liquid whole egg (LWE) at different NaCl concentrations (0-3%, w/w) were investigated to provide guidance for the production of salty LWE. Results showed that LWE exhibited higher particle size after heating, with coincidental increases in surface hydrophobicity and decreases in protein solubility. While LWE with NaCl added exhibited increase in protein solubility and decrease in particle size of aggregates. Electrophoresis and optical microscopy showed that NaCl would induce the transformation of egg granules from insoluble form to soluble form, inhibiting the aggregation of LWE proteins during preheat treatment, reflected by the reduced particle size. The analysis of gel aggregated force and texture indicated that NaCl addition and preheat treatment can improve gelling properties of LWE synergistically by strengthening the hydrophobic interaction and hydrogen bonds.

Keywords: Aggregation behavior; Gel properties; NaCl; Preheat treatment; Whole egg proteins.