Improvement of myofibrillar protein gel strength of Scomberomorus niphonius by riboflavin under UVA irradiation

Abstract

In this study, effects of different concentrations of riboflavin (0, 0.02, and 0.1 μmol/g protein) on myofibrillar protein (MP, Scomberomorus niphonius) gel were characterized. The gel structure and properties were studied with or without Ultraviolet A (UVA) irradiation. Electron spin resonance results showed that riboflavin produced ·OH under UVA irradiation, which subsequently oxidized the MP. Compared with the control group, the addition of riboflavin with UVA irradiation increased the strength of the MP gel. The rheological results showed that under UVA irradiation, addition of riboflavin facilitated the sol–gel transition between 45 and 52°C, indicating that oxidation led to significant structural changes which in turn resulted in a more compact and uniform gel network. The presence of riboflavin led to increased carbonyl content and decreased sulfhydryl and free amino groups, which decreased the protein solubility and promoted alpha‐helical conformational loss in the secondary structure of the MP. These results all indicated that the MP has been oxidized. Electrophoresis revealed that myosin heavy chains were aggregated in the UVA‐treated riboflavin‐added MP gel, indicating that protein cross‐linking has been induced. All the results indicated that the ·OH produced by riboflavin under UVA irradiation oxidized the MP, and improved protein crosslinking and gel properties.

Synergistic effects of UVA irradiation and phlorotannin extracts of Laminaria japonica on properties of grass carp myofibrillar protein gel

“…SDS‐PAGE was used to evaluate the crosslinking patterns of proteins in the MP gel samples as described by He et al 23 . An amount of 20 μg of sample was applied to a gel consisting of 5% concentrating gel and 10% separating gel.…”

UV irradiation improved gel properties and chill‐stored stability of surimi gel

“…UV irradiation might also expedite the autooxidation of myoglobin to metmyoglobin in surimi to generate browning (Buamard and Benjakul 2019). Nevertheless, compared with the sharp decline of whiteness in surimi gel incorporating polyphenols and riboflavin received UV irradiation reported by He et al ., (2020b) and Jiang et al ., (2020), whiteness change in our study is negligible.…”

Impacts of yeast β‐glucan on thermal aggregation and flavour adsorption capacity of Spanish mackerel myosin

“…During the heating process, the hydrogen bonds and hydrophobic interactions that maintained the helical structure were destroyed, which promoted the α‐helix construction to continue unfolding and transforming to other forms (Li et al ., 2020c). In addition, some studies suggested that the rise of β‐sheets content provided favourable conditions for the irreversible aggregation of myosin and the formation of a stable gel network (He et al ., 2020b). By contrast, the content of α‐helix in the M‐YG group was lower than that in the M group.…”

“…Spanish mackerel ( Scomberomorus niphonius ), with a higher yield in China, is an alternative resource that has attracted more attention. However, prepared surimi has a limited flavour and gel quality because of the significant proportion of red meat in its muscles (He et al ., 2020b). Therefore, it is important to find methods to improve the quality of such surimi.…”