Gelation properties and protein conformation of grass carp fish ball as influenced by egg white protein

Abstract

Dried egg white powder (EWP) and purified ovalbumin (OVA, 98%) were used as supplements to improve grass carp (GC) fish balls (FB) quality. The effects of EWP and/or OVA contents on the gel strength, water holding capacity (WHC), moisture migration and distribution, and rheological properties of GC-FB, as well as on myofibrillar protein (MfP) structures in the GC-FB were evaluated. The results showed that with the increase of EWP addition from 0 to 4% (w/w), the gel strength, and WHC of the GC-FB samples were increased from 34.28 to 66.63 N Â mm, and 83.02 to 88.36%, respectively, but the increases were insignificant between 3 and 4% EWPadded GC-FBs (p > .05). As the EWP increased, the T 2 relaxation time shifted toward lower values, indicating a general decline in water mobility. The effects of EWP on rheological properties were insignificant. Addition of OVA and/or EWP led to changes in secondary structural units in the FB, with α-helix (27.53%) reaching the highest value in OVA-added GC-FB, β-sheet (46.07%) reaching the highest value in GC-FB, and β-turn (33.54%) reaching the highest value in EWP-added GC-FB, respectively. Raman spectroscopy revealed that OVA-added GC-FB had the lowest hydrophobic interlinkages. Protein pattern analysis suggested that the OVA (1.58%) might contribute to the decrease in the myosin heavy chain band intensity through cross-linked with MfP. These results suggested that EWP could improve the quality of GC-FBs and OVA played an important role with MfP gelation.

Textural and physicochemical properties of threadfin bream surimi gels prepared with salted duck egg white as substitute for hen egg white

“…The egg white functions as a filler in surimi gel by enhancing gelling properties. Ovalbumin, a major protein component of both egg whites, forms a network of gel itself as well as cross‐links with myofibrillar protein (Lv et al ., 2022; Yu et al ., 2022). Furthermore, protease inhibitors (including ovalbumin, ovotransferrin, ovomucoid, ovoinhibitor and cystatin) present in the egg white could inhibit cysteine protease and serine protease enzymes responsible for the degradation of the myofibrillar proteins in fish muscle (Quan & Benjakul, 2017).…”

“…2, addition of SDEW to the gels reduced the expressible moisture content from 44% to 36% compared with the gels without SDEW ( P < 0.05), thereby indicating an increase of their WHC properties. Addition of egg white protein to surimi gel resulted in lower expressible moisture content of surimi gel, since this result correlated with a reduction of free water content which can be determined using a low‐field nuclear magnetic resonance (LF‐NMR) (Yu et al ., 2022). As the free water was transformed to immobilised water molecules, the water was not easily removed from the gel network (Zhang et al ., 2022).…”

Improving the Gel Quality of Threadfin Bream (Nemipterus spp.) Surimi Using Salted Duck Egg White Powder

“…A lower EMC value indicated higher water holding capacity (WHC) of surimi gel as the gel could release less water and trap more water inside its gel network [ 29 ]. Surimi made from lizardfish, goatfish, bigeye snapper, Indian mackerel, and grass carp showed increased WHC when egg white proteins were added to the gel [ 5 , 27 , 30 ]. Both myofibrillar proteins and egg white proteins could form a strong gel network, which could entrap more water inside.…”

“…The non-sulfide covalent bond, which is induced by transglutaminase during the setting process, cannot be cleaved by either SDS (cleaves non-covalent bond) or 2-mercaptoethanol (cleaves disulfide bond) contained in the sample buffer. Thus, the high molecular weight protein aggregates formed during the setting process remain intact and retained in the wells as they could not pass through the stacking gel [ 30 ]. This resulted in the disappearance of the MHC band in every gel sample’s protein pattern.…”

Effect and synergy of different exogenous additives on gel properties of the mixed shrimp surimi (Antarctic krill and white shrimp)

“…Modified starches have demonstrated capacity to improve gel strength and elasticity of foods, a feature which supports their application in surimi products (Kong et al., 2016). Egg white powder (EWP) has been showed to increase WHC and gel strength of surimi gel, leading also to greater density surimi gel microstructure (Yu et al., 2022). Mi et al .…”