Search Results (142)

This study aimed to investigate the effects of the phycocyanin–rosmarinic acid (PC-Ra) emulsion on the gel quality of surimi. PC-Ra conjugates were synthesized firstly via laccase-catalyzed oxidation at different Ra concentrations, and their physicochemical properties—including grafting degree, sulfhydryl group content, free amino group content, and surface hydrophobicity—were characterized. The results demonstrated that Ra addition effectively reduced free amino groups, achieving optimal grafting at 30 μmol/L along with peak disulfide bond content and surface hydrophobicity in the PC-Ra conjugate. This was thus attributed to covalent bond formation, as confirmed by FTIR spectroscopy. The PC-Ra emulsion was then incorporated into surimi gels and compared with gels containing directly added corn oil. The results indicated that the PC-Ra emulsion significantly improved the textural properties of surimi gels. Furthermore, it enhanced water-holding capacity, reduced cooking loss, and delayed lipid oxidation. Among all formulations, the PC-Ra 30 emulsion exhibited the most pronounced effects and shows potential as a fat replacer in surimi gel preparation, yielding products with superior quality. This study provides a theoretical basis and technical support for developing novel surimi gel products. Full article

Growing demand for low-sodium surimi products has driven the search for safe salt alternatives. Anionic peptides (APPs) and cationic peptides (CPPs) were isolated from sheepskin collagen via Diethylaminoethyl (DEAE) chromatography. CPPs contained higher arginine (46.11%) and lysine (4.64%) than APPs (40.57% and 3.99%, respectively), while APPs were enriched in acidic amino acids like glutamic acid (3.88%). Comprehensive evaluations of low-salt silver carp surimi gels showed both peptides significantly improved gel strength and water-holding capacity (WHC). The water-holding capacity increased from 60.68% in the blank control group to 74.31% in the CPP-treated group, while that in the APP-treated group was 66.86%. Cooking loss was significantly reduced, decreasing from 40.64% in the blank control group to 28.57% in the CPP-treated group and 34.52% in the APP-treated group. The samples achieved a quality comparable to that of the NaCl-supplemented group, with CPP outperforming APP in terms of hardness and gel network density. The LF-NMR confirmed enhanced water retention by reducing free water (T₂₂) and increasing bound water (T₂b). The FTIR indicated a conformational shift from α-helix to β-sheet, and the SEM revealed denser networks with fewer large voids. The SDS-PAGE demonstrated enhanced myosin heavy chain (MHC) cross-linking, more pronounced in the CPP-treated samples. CPPs exerted stronger electrostatic attraction with negatively charged surimi proteins (isoelectric point 5.5), while APPs chelated Ca²⁺ to activate transglutaminase. These findings validate APPs and CPPs as promising salt substitutes, enabling low-sodium surimi production and high-value utilization of sheepskin by-products. Full article

Antarctic krill surimi is a novel type of gel-based food that has attracted increasing attention. However, pure Antarctic krill surimi generally exhibits poor gel-forming properties. Konjac glucomannan (KGM) offers a promising approach to address this limitation due to its gel-forming ability and thermal stability. This study investigated the effect of KGM (0.0–20.0 mg/g) on the functional properties and structural characteristics of Antarctic krill-KGM surimi gels. The results demonstrated that as KGM levels increased, water-holding capacity, whiteness, hardness, chewiness, and gel strength of the composite surimi gels first increased and then decreased, while cooking loss followed the opposite trend. Texture analysis showed that gel strength was significantly enhanced at 10.0 mg/g KGM, reaching a maximum value of 1581.78 ± 12.86 (p < 0.05). Water distribution analysis confirmed that the relative content of immobilized water increased with increasing KGM levels. Fourier transform infrared spectroscopy demonstrated that the Antarctic krill-KGM surimi gels were primarily linked by non-covalent intermolecular interactions. Furthermore, microstructural analysis showed that KGM contributed to a more homogeneous and continuous gel matrix. These results indicate that KGM can modulate electrostatic repulsion, spatial potential resistance, and act as a reinforcing filler in the surimi gel matrix. Overall, the results demonstrated that KGM is a feasible candidate for enhancing the quality of Antarctic krill surimi gels. Full article

To investigate the effect of a polysaccharide-based composite film (ASC) composed of Alpinia oxyphylla polysaccharide (its molecular weight was approximately 4.07 kDa, and the monosaccharide composition was predominantly glucose and galacturonic acid), sodium alginate, and calcium chloride on the storage quality of shrimp surimi, this study compared the preservation efficacy of the ASC film with that of treatments using chitosan, potassium sorbate, ascorbic acid, sodium alginate, Alpinia oxyphylla polysaccharide, and distilled water. Samples were stored at 4 °C for 12 days, and evaluations were conducted by measuring film structural characteristics and quality indicators of shrimp surimi. Results showed that the ASC groups (where Alpinia oxyphylla polysaccharide was added at 20%, 30%, and 40% of the sodium alginate mass, designated as ASC 20%, ASC 30%, and ASC 40%) significantly outperformed the control group across all quality indicators. The ASC 30% group demonstrated the best overall preservation performance, effectively delaying oxidative browning, protein degradation, lipid oxidation, and microbial growth in shrimp surimi. The ASC 40% group exhibited particularly strong antibacterial effects, while the ASC 20% group also showed stable preservation performance. The composite film combines the antioxidant and antibacterial activities of Alpinia oxyphylla polysaccharide with the barrier and moisture-retention properties of sodium alginate, forming a stable three-dimensional network structure through calcium chloride cross-linking. It is superior to single/individual chemical preservatives in terms of film-forming ability, functionality, and safety, providing a natural, effective, and environmentally friendly preservation approach for shrimp surimi and other aquatic products. It also offers a theoretical foundation and practical reference for the development of natural preservation technologies in the food industry. Full article

To improve the gel quality of low-salt shrimp surimi gel (SSG) from Pacific white shrimp (Litopenaeus vannamei), L-arginine (L-Arg), L-lysine (L-Lys), and L-proline (L-Pro) were used as partial substitutes for NaCl. The effect of the three amino acids on gel properties, protein conformation, microstructure, and in vitro digestion of low-salt SSG were systematically analyzed. Macro-/microstructural analyses revealed that L-Arg, L-Lys, and L-Pro promoted denser three-dimensional networks in low-salt SSG with smaller pore sizes. Compared with the low-salt control (LC) group, the addition of L-Arg, L-Lys, and L-Pro significantly increased the gel strength of low-salt SSG. Cooking loss was significantly decreased from 10.80% (LC group) to 1.89–4.31%. Protein solubility and turbidity results demonstrated that all amino acids markedly enhanced protein solubilization and inhibited protein aggregation. L-Arg and L-Lys mainly promoted hydrogen and disulfide bonds, but reduced hydrophobic interactions and ionic bonds. L-Arg impaired digestibility only in the gastric phase, whereas L-Lys suppressed digestibility across both gastric and intestinal phases. Through molecular docking technology, ASN-238 and LYS-187 of myosin (the dominant gel-forming protein) are the key shared binding residues with three amino acids. These findings suggest that amino acids provide a feasible approach to specifically modulate the gel characteristics of low-salt surimi products. Full article

This study aimed to develop a dietary fiber-rich Antarctic krill composite shrimp surimi gel (AKSG) and to investigate the improvement effects of high protein (HP), high protein and dietary fiber (HPDF), and high dietary fiber (HDF) diet interventions on constipation behaviors and gut microbiota of mice. The results showed that the HPDF group significantly improved defecation in constipated mice, enhanced gastrointestinal peristalsis, and exhibited the most obvious effect on improving the colonic structure. The gut microbial analysis showed that the HPDF group increased the relative abundance of beneficial bacteria and improved the intestinal microbial environment of constipated mice. In addition, all groups effectively regulated the secretion of intestinal neurotransmitters. Inulin significantly increased the fecal water content by binding to water molecules, thus softening feces. Meanwhile, the addition of an appropriate amount of protein could further absorb water in the intestinal tract and relieve constipation. In conclusion, dietary fiber-rich AKSG might be a promising nutritious functional food for constipation relief. Full article

This study evaluated the responses of five sunflower (Helianthus annuus L.) hybrids (Surimi CL, Integral CL, Alexa SU, Neta SU, and Davero SU) to three planting densities (84,034, 68,027, and 57,143 plants/ha) in terms of agronomic performance and photosynthetic efficiency. Higher plant density reduced leaf area and seed weight but enhanced uniformity of head formation. Among the tested hybrids, Integral CL and Surimi CL demonstrated superior performance under high density, maintaining higher chlorophyll content, photosynthetic activity, and yield stability. In contrast, Davero SU performed best under low density, characterized by greater leaf expansion, seed filling, and overall productivity. These findings highlight the potential of integrating physiological and agronomic traits to inform hybrid-specific planting density optimization under diverse environmental conditions. Full article

This study investigated the effects of direct vat set commercial yoghurt starter (B) and yeast starter (Y) on the quality of fermented large yellow croaker surimi balls, with natural fermentation (CTR) as a control. Surimi products were inoculated and fermented at 25 °C for 4 h, then analyzed for physicochemical, sensory, and oxidative properties. Yoghurt starter significantly inhibited protein oxidation, as indicated by the highest sulfhydryl content (9.10 nmol/mg protein, p < 0.05), improved textural properties (hardness was 28% higher than CTR, p < 0.05), and promoted a balanced flavor profile, accompanied by the highest equivalent umami concentration (1.66%, p < 0.05). However, B also caused the greatest MDA accumulation (1.49 mg/kg, p < 0.05), reflecting enhanced lipid oxidation. By comparison, Y enhanced umami primarily through significant enrichment of aspartic acid (53.88 mg/100 g, p < 0.05) and accelerated nucleotide degradation, resulting in the highest AMP and hypoxanthine levels (p < 0.05). These advantages were offset by severe protein carbonylation (54.32 nmol/mg protein, p < 0.05) and evident color deterioration. Sensory analysis revealed no significant difference between B and CTR (p > 0.05), whereas Y received significantly lower acceptance scores (p < 0.05) due to impaired color and taste. These findings suggest that B is a promising starter for improving texture and flavor in fermented surimi balls, while Y, despite enhancing umami and controlling lipid oxidation, negatively affects color, texture, and protein stability. Full article

The giant squid, despite its abundance as a resource, is underutilized for surimi production due to its distinctive odor and poor gel-forming ability. While soaking (e.g., in sodium citrate) can alleviate the odor, its impact on the gel properties remains unclear. This study employed a comparative approach using pork, a benchmark for high-quality gels, to critically evaluate the gel properties of deodorized giant squid. The rheological, textural, and microstructural properties, as well as the water-holding capacity and water distribution, of squid (after sodium citrate soaking) and pork gels were compared. The results demonstrated that the squid gels exhibited a significantly lower storage modulus and higher tan δ value than pork gels, indicating inferior rheological properties. After cooking, the squid gel exhibited a bent shape and markedly lower hardness (approximately 259.78 g) and chewiness (approximately 226.09 g) compared to the pork gels (approximately 3305.92 g and 2781.27 g, respectively). Microstructurally, the squid gels presented a coarse, porous, and discontinuous network with larger pores, contrasting sharply with the fine, dense, and uniform matrix of the pork gels. Correspondingly, the squid gels had inferior water-holding capacity and a higher proportion of free water. This comparison demonstrates that the gel from sodium citrate-soaked giant squid is weak. More importantly, it provides mechanistic insights by highlighting the specific structural and hydration deficiencies responsible for its poor performance. The findings underscore that targeted strategies to modify the protein network are necessary for the effective utilization of giant squid in surimi production. Full article

In this study, whey protein isolate–soybean lecithin-encapsulated vitamin A emulsion (V_A-WSE) with different oil-to-water ratios was prepared and characterized. The impact of V_A-WSE on the physicochemical characteristics of Nemipterus virgatus surimi at varying concentrations was determined. The V_A-WSE emulsion exhibited the best stability when the oil-to-water (O:W) ratio was 1:1 (w/w). Composite gels prepared by mixing V_A-WSE (O:W = 1:1, w/w) with surimi at different ratios showed significantly improved gel properties. In particular, the hardness, chewiness, gel strength, and water-holding capacity of the composite gel with a V_A-WSE concentration of 8% (w/w) reached the highest values of 2629.00 g, 2051.27 g, 292.16 g·cm, and 87.10%, respectively. Similarly, the observed voids in the microstructural images gradually decreased with rising V_A-WSE concentration and were the smallest in the 8% sample group. Surimi gels showed remarkably enhanced hydrogen bonds in the V_A-WSE concentration range of 0–8%, increasing from 0.001 to 0.025 mg/mL (p < 0.05). Furthermore, it was observed that the energy storage modulus (G′) was larger than the loss modulus (G″), suggesting the dominant elastic characteristics of the composite gels. The solubility and total sulfhydryl group contents significantly increased from 30.33 to 88.29% and from 4.90 to 28.19 nmol/mg, respectively. In summary, V_A-WSE can promote the unfolding of the myofibrillar protein (MP) structure and improve the gel properties of surimi gels. These results support the development of functional surimi products. Full article

The invasive Silver Carp (Hypophthalmichthys molitrix) in North America represents a promising resource for surimi production; however, its gel formability deteriorates significantly during frozen storage. This study investigated the deterioration of gel properties in Silver Carp surimi over six months of frozen storage, and showed that short-term frozen storage (<2 months) was beneficial for surimi gel-forming ability, while extended frozen storage (>2 months) tended to have detrimental effects. The adverse effect of long-term frozen storage could be mitigated via using food additives (e.g., manufactured microfiber, transglutaminase, and chicken skin collagen), among which transglutaminase was the most effective. Transglutaminase at a relatively low level (0.1 wt%) could effectively negate frozen storage’s effects, and produced surimi gel with quality attributes (e.g., gel strength, hardness, and chewiness) at levels comparable to those from fresh fish samples. To assess the effects of the addition of various food additives for quality improvement, a synthetic data-driven machine learning (SDDML) approach was developed. After testing multiple algorithms, the random forest model was shown to yield synthetic data points that represented experimental data characteristics the best (R² values of 0.871–0.889). It also produced improved predictions for gel quality attributes from control variables (i.e., additive levels) compared to using experimental data alone, showing the potential to overcome data scarcity issues when only limited experimental data are available for ML models. A synthetic dataset of 240 data points was shown to supplement the experimental dataset (60 points) well for assessment of the Frozen Silver Carp (FSC) surimi gel quality attributes. The SDDML method could be used to find optimal recipes for generating additive profiles to counteract the adverse effects of frozen storage and to improve surimi gel quality to upgrade underutilized invasive species to value-added food products. Full article

Potato protein (PP) at concentrations of 0.025–0.3% was added to tropical fish surimi, including lizardfish (LZ) and threadfin bream (TB), and cold-water fish, namely Alaska pollock (AP) and Pacific whiting (PW), to examine its effect on proteolytic inhibition and surimi gel texture. Tropical fish surimi, particularly LZ, exhibited the highest degree of autolysis induced by endogenous proteases (p < 0.05), as evidenced by degradation of myosin heavy chain and tropomyosin. PP demonstrated a broad range of proteolytic inhibition activities against chymotrypsin, trypsin, papain, and cathepsin L, with chymotrypsin being the most susceptible. At a PP concentration of 0.3%, the highest autolytic inhibition was obtained in AP (72.24%), followed by LZ surimi (60.44%, p < 0.05). Egg white protein (EW) showed autolytic inhibitory activity at 14.50–50.52% in all species at 0.3%. Surimi gels with only 0.025% PP exhibited breaking forces and distance comparable to those with added 0.3% EW, regardless of the cooking regimes. In tropical surimi, PP at 0.3% increased the breaking force by 4.13–5.38-fold under a setting condition (as the best heating regime) compared with the control. At this concentration, PP decreased the whiteness of LZ and AP in the set surimi gels by 7.03% and 6.42% (p < 0.05), respectively, whereas its effect on TB and PW surimi was negligible. The study demonstrates that PP can be a promising alternative to EW to control proteolytic degradation and improve textural properties of cold-water and tropical surimi. Full article

This study aims to improve the gel properties of Nemipterus virgatus myofibrillar protein (MP) emulsion gels by Curdlan (Cur) and investigate the effect of the emulsion gels on the quality of emulsified surimi gels. The effects of different concentrations of Cur on the gel properties of MP emulsion gels were investigated. Fourier transform infrared (FTIR) results indicated that intermolecular interactions between Cur and MP were primarily hydrogen bonds. Cur enhanced the adsorption capacity of MP at the oil/water interface, inducing the formation of a more uniform and dense composite network structure in Cur/MP emulsion gels. Adding 6% (w/v) of Cur significantly increased the hardness, gel strength, water-holding capacity (WHC) and rheological properties of the gel. In addition, microstructural images showed that MP formed a complex interpenetrating network with Cur, thus enhancing the gel network skeleton. Low-field NMR confirmed that the addition of Cur decreased water mobility in the emulsion gel system. Compared to the direct addition of oil, the application of Cur/MP emulsion gels to surimi significantly improved the texture, gel strength, and WHC of the surimi gel. These findings provide a reference for the development of myofibrillar protein emulsion gels and broaden their potential application in the food industry. Full article

Snack foods (e.g., extruded flour-based products) are widely favored by consumers because of their convenience, affordability, and time-saving attributes. However, with the growing demand for high-quality snacks, several challenges have emerged that hinder industry development, such as relatively underdeveloped industrial standards, limited raw material diversity (primarily starch and soy protein), and, consequently, insufficient nutritional value. In this study, a novel type of puffed snack was developed using Alaskan pollock surimi and wheat flour using extrusion puffing technology. The effects of varying ratios of surimi to wheat flour (0:10, 1:9, 2:8, 3:7, and 4:6, which served as SFBC, SFB1, SFB2, SFB3, and SFB4, respectively), on the physicochemical properties, apparent morphology, microstructure, thermal stability, and protein structure of spicy strips were systematically investigated, and the interaction between extruded protein and flour mixtures was analyzed. The results indicated that increasing the proportion of surimi led to decreases in hardness, elasticity, and chewiness, whereas the moisture content and water solubility index increased. The maximum expansion rate (202.2%) was observed in the SFB1 sample. Morphological and microstructural observations further revealed that a higher surimi content resulted in a denser internal structure and a reduced degree of puffing. The protein distribution was relatively uniform, with large pores. Moreover, increased surimi content increased the proportion of immobilized water and improved the thermal stability. These findings provide valuable insights into starch–protein-complex-based extrusion puffing technologies and contribute to the development of innovative surimi-based puffed food products. Full article