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Alcoholism is a serious public health problem, and the abuse of drinking seriously damages the health of people. Chitosan oligosaccharides (COSs) are small‐molecule oligosaccharides with amino groups that have many unique properties. The neuroprotective effect of COS on alcohol‐induced hippocampal injury in Sprague–Dawley (SD) rats was investigated. The discrimination ratio of the COS group in the Y‐maze experiment was 59.3% higher than that of the ETOH group. Meanwhile, the discrimination index was less than 0 in the ETOH group but greater than 0 in the COS group during the object recognition test. The cells in the COS group were more tightly arranged than those in the ETOH group. Proteomics was used to identify differentially expressed proteins in the hippocampus. There were 27 differentially expressed proteins in the COS and ETOH group for further bioinformatic analysis. There are three enriched pathway categories, namely, primary immunodeficiency, hedgehog signaling, and sulfur relay system. Next, sonic hedgehog signaling pathway‐related proteins were verified through western blotting. The protein expression level of β‐arrestin‐2 in the COS group was 2.85 times higher than that in the ETOH group. This work may contribute to understanding the underlying mechanism of the neuroprotective effect of COS against alcohol‐induced hippocampal injury in SD rats. [ABSTRACT FROM AUTHOR]

The freeze‐thawing (FT) stability generally correlates well with the economic value and acceptability of frozen surimi‐based products. However, quality changes of emulsified surimi gels under FT conditions are still unclear. Therefore, the gel properties of samples with different phase states of lipids (lard, lard + soybean oil, and soybean oil) were investigated at FT conditions. Results showed that the soybean oil evidently improved the rheological behaviors of sols/gels compared to the lard group. The moisture content of samples with different lipids decreased by 2.40%–2.71% after 4 FT cycles. With increasing FT cycles, the water‐holding capacity decreased accompanied by the increase of cooking loss. Spin–spin relaxation spectra and hydrogen proton density images proved the occurrence of water migration of gels during these processes. Better gel integrity was observed in samples consisting of soybean oil, where the proportion of pores was lower than those with lard regardless of FT treatments. Additionally, the intermolecular forces of gels also changed under FT treatments. There results suggested that the lipids with different phase states affected the migration and loss of water in emulsified surimi gels under FT cycles. Practical Application: The quality changes of heating‐induced surimi gel products under frozen storage have been ignored, especially the emulsified surimi gels. This study discloses the changes of the gel properties in emulsified gel products with different phase states of lipids after FT treatments, which provides critical insights into the quality improvement of this novel emulsified surimi product during processing, storage, and transportation. [ABSTRACT FROM AUTHOR]

The structural and physicochemical characteristics of protein hydrolysates prepared from Chinese sturgeon through the enzymatic hydrolysis process were evaluated. Two different enzymes including papain and alcalase 2.4L were used in the hydrolysis process. The papain enzyme significantly increased the degree of hydrolysis (20.62%) and decreased the ζ‐potential (12.4 ± 1.31 mV) as compared to the alcalase enzyme, which represented 15.55% and 15.53 ± 0.77 mV, respectively. Alcalase 2.4L hydrolysate exhibited smaller particle size (822.047 ± 61.26 nm) than papain hydrolysate (1425.39 ± 44.82 nm). Hydrolysis by papain and alcalase 2.4L enzymes decreased the molecular weights (MW ≤ 1,000 Da) to 98.27% and 86.84%, respectively. The surface hydrophobicity and turbidity of the hydrolysates significantly affected by enzyme type and protein concentrations. By using the X‐ray diffraction analysis, the papain hydrolysate showed a higher relative crystallinity degree (30.33%) than alcalase 2.4L hydrolysate (29.40%), whereas the Fourier transform infrared spectroscopy showed more clearly peaks for the amide bands of alcalase hydrolysate. The thermal properties also affected by enzymatic hydrolysis conditions, since the melting temperatures were 159.17 and 149.58 °C, whereas the rate of mass loss was 67.04% and 62.8%, for papain and alcalase hydrolysates, respectively. Practical Application: The enzymatic hydrolysis process of proteins is employed to obtain the nutritionally and functionality important peptides that result during the preparation of fish protein hydrolysate. The objective of this study was to investigate the structural and physicochemical characteristics of protein hydrolysate prepared from Chinese sturgeon. This study showed that these characteristics were affected by enzymatic hydrolysis conditions especially enzyme type. The finding of this study may be useful in terms of providing new information on the properties of the protein hydrolysate and the structural changes resulting from controlled enzymatic hydrolysis conditions. Overall, these conditions could potentially alter the secondary structure of the protein hydrolysates or peptides and enhance their functional properties. [ABSTRACT FROM AUTHOR]

Battered and breaded fish nuggets (BBFNs) were prepared by treating fish with a batter composed of wheat starch (WS) and wheat protein (WP) blends (at the ratios of 15:1, 13:1, 11:1, 9:1, and 7:1, w/w), frying at 170 °C (40 s) followed by 190 °C (30 s). Fried BBFNs were evaluated for moisture and fat contents, color, shrinkage, acrylamide content, and fat distribution. Results showed that moisture content and brightness (L* value from colorimetry) increased with a decrease of WS/WP ratio to 11:1 w/w, then decreased as WS/WP ratio further decreased, while fat content, fat distribution level, and shrinkage of fried BBFNs presented opposite results. However, there was a slight influence of WS/WP ratio on yellowness (b* value), redness (a* value), and acrylamide content of fried BBFNs. Among WS/WP ratios, fried BBFNs with 11:1 w/w have the highest moisture content (16.43%) and the lowest fat content (23.39%), fat distribution level, shrinkage (10.72%), and acrylamide content (57 mg/kg), while a crust with golden‐yellow color was observed. This study demonstrates that moisture evaporation and fat absorption were significantly influenced by WS/WP ratio in the batter (P < 0.05), with the most effective results in quality attributes improvement of fried BBFNs. Practical Application: This study clearly showed that the fat content and quality attributes of fried BBFNs were significantly affected by WS/WP ratio in the batter (P < 0.05). The inhibition of fat absorption and improvement of shrinkage and color in fried BBFNs was the most effective for a 11:1 w/w WS/WP ratio. [ABSTRACT FROM AUTHOR]

Abstract: Xanthan gum (XG) and soybean fiber (SF) at varying ratios were incorporated into the batter to inhibit oil absorption in fried battered and breaded fish nuggets (BBFNs). BBFNs were prepared with 1.2% XG and SF blends (at ratios 1:3, 1:2, 1:1, 2:1, and 3:1 w/w), fried at 170 °C (40 s) followed by 190 °C (30 s), then evaluated for pickup, oil absorption, textural characteristics, and other quality attributes. Compared with the control (without the addition of XG and SF), fried BBFNs prepared with XD and SF had a significantly reduced fat content (P < 0.05). Among all the treatments, fried BBFNs with a 1:2 w/w ratio of XG and SF had the lowest fat content in the crust and the core (16.2% and 0.6%, respectively) and the highest moisture content. When compared with other treatments, the 1:2 w/w treatment group displayed a more intense golden yellow color, higher crispness, lower hardness, and a more compact structure in the crust, a greater elasticity and chewiness of the core, and the least oil penetration. The results proved that the combined addition of XG and SF in the batter can effectively inhibit oil absorption, which may be used to guide the production of low‐fat fried BBFNs. Practical Application: This study clearly showed that the combined addition of XG and SF at different ratios in the batter significantly affected fat content and quality attributes of fried BBFNs. The inhibition of oil absorption and improvement of color and textural characteristics in fried BBFNs depended on the XG/SF ratio added to the batter, and a 1:2 w/w ratio was found to produce the maximum enhancement. [ABSTRACT FROM AUTHOR]