A comparative study on the taste quality of Mytilus coruscus under different shucking treatments

Elevating sensory quality through a dual-acid preservation strategy in ready-to-eat crayfish (Procambarus clarkii)

This study presents a targeted dual-acid preservation strategy for ready-to-eat crayfish (Procambarus clarkii), integrating a blend of phytic and lactic acids to fortify key sensory attributes throughout the storage phase. The primary objective was to maintain the sensory attributes of the crayfish during a 30-day storage period under 40 °C. Our approach significantly bolstered color retention by suppressing Maillard reactions and lipid oxidation, thereby maintaining the product's visual allure. The strategy also fortified texture stability through the mitigation of oxidative myofibrillar protein degradation, pivotal for the crayfish's sensory experience. By preserving the myofibrillar structure, this dual-acid preservation strategy ensured the longevity of non-volatile flavor compounds and adeptly regulates free water content, averting quality diminution. The study underscores the efficacy of a 0.06 % phytic acid and 0.08 % lactic acid solution in the aquatic food industry, advocating for further exploration into the nuances of application and thermal processing dynamics.

Impact of Cooking Processes on Volatile Flavor Compounds and Free Amino Acids in Fish Sauce

Fish sauce is a widely used condiment in cooking. However, the effects of various cooking processes on its quality remain poorly understood. This study evaluated the quality of fish sauce subjected to various cooking methods (boiling for 10, 30, and 60 min and stir-frying for 10, 30, and 60 s) using sensory evaluation, electronic nose, gas chromatography-mass spectrometry, and free amino acid analysis. Thermal cooking processes significantly altered the flavor profile of the fish sauce. A total of 38 volatile compounds were identified and quantified, 10 of which were screened as key aroma-active compounds based on their high odor activity values (OAVs ≥ 1). The total OAV values of key flavor compounds were lowest in unheated fish sauce (346.51) and varied from 347.64 to 707.40 in heated fish sauce. The maximum total free amino acid contents in boiled and stir-fried fish sauce were 4862.52 mg/100 mL and 4922.49 mg/100 mL, respectively, which were significantly higher than those in unheated fish sauce (4577.54 mg/100 mL) (p < 0.05). Pearson correlation analysis indicated that temperature modulates the production of key flavor compounds in fish sauce by influencing amino acid metabolism. These findings provide valuable insights into the application of fish sauce in food production and culinary practices.

Key non-volatile taste components and characteristics in abdominal muscle of Eriocheir sinensis under various thermal processing methods

This study identified the key non-volatile taste components and characteristics in the abdominal muscle (AM) of Eriocheir sinensis under various thermal processing methods: boiling at rising temperature (BO-R), boiling at constant temperature (BO-C), steaming with water vapor (ST) and salt-baked (BK). The results showed that arginine (Arg), alanine (Ala), glycine (Gly), glutamate (Glu), 5'-AMP, histidine (His), lysine (Lys), proline (Pro), K+, PO43-, betaine, succinic acid, and lactic acid were the key taste contributors, exhibiting taste activity values (TAV) higher than 1.0. Compared to BO groups, ST and BK group showed higher expression in SFAAs. BK exhibited the highest Arg, 5'-AMP contents, EUC (4.49 g MSG/100 g), and reduced BFAAs. The cluster and correlation analysis demonstrated that Arg, Ala, and His were identified as the primary differential components under various thermal degradation. These findings could deepen the understanding of taste for subsequent studies.

Insight into the correlation of taste substances and salty-umami taste from Monetaria moneta hydrolysates prepared using different proteases

To prepare dual-functional seasoning ingredients with a salty-umami taste, five proteases were applied to hydrolyze Monetaria moneta proteins, preparing enzymatic hydrolysates. Their taste compounds along with the salty-umami taste, were investigated. The results revealed that enzymatic hydrolysis facilitated the release of taste compounds from M. moneta. The whiteness and < 3 kDa peptides of enzymatic hydrolysates significantly increased. Moreover, flavorzyme and protamex, with high DHs, could thoroughly hydrolyze the proteins, generating the enzymatic hydrolysates abundant in taste compounds (e.g., amino acids, nucleotides) that synergistically provided a strong salty-umami taste. Saltiness and umami posed a strong positive correlation, with a correlation coefficient exceeding 0.90, resulting in the highest levels of equivalent salty intensity (ESI = 80.05 gNaCl/L) and equivalent umami concentration (EUC = 84.56 gMSG/100 g) in the flavorzyme-treated hydrolysate, followed by the protamex-treated hydrolysate. In summary, these findings offer novel insights into preparing dual-functional seasoning ingredients with a salty-umami taste, ideal for use in low-salt food production.

Elucidating the effects of precooked treatments on the quality attributes of red swamp crayfish (Procambarus clarkia): Insights from water boiling vs. microwaving

Precooked treatments are essential in food processing, extending beyond mere sterilization to include the enhancement of nutritional value, flavor profile, and digestibility. This research scrutinizes the effects of water boiling and microwaving on red swamp crayfish, two distinct precooked methodologies. A comparative analytical framework has been employed to assess the efficacy of two precooked methods across a spectrum of quality indicators, including aerobic plate counts, texture, nutrient composition, volatile compound characterization, protein oxidation, and digestive properties. The findings revealed that both water boiling and microwaving effectively reduced bacterial counts to a safe level of 500 CFU/g. Microwave precooking facilitated a moderate oxidation of lipids in crayfish, preferentially liberating flavor compounds, thereby enhancing their sensory attributes. The boiling process imparted a pronounced denaturation to proteins, consequently augmenting the hardness of the crayfish. Notably, the enhanced digestibility of boiled crayfish proteins results from the denaturing action of boiling, promoting efficient protein digestion.

The Attachment of Juvenile Mussels via Byssus Weakened by Contaminated Polyethylene Fibers

In the process of mussel farming, the rope for attachment is indispensable, as it provides a stable attachment environment for mussel seedlings, directly affecting their survival rate and growth quality. The objective of this study is to examine the contamination of ropes, composed of polyethylene fibers, by heavy metals and polycyclic aromatic hydrocarbons (PAHs) after three years of deployment and to assess its influence on the attachment and locomotion behaviors of juvenile mussels. Utilizing a laboratory simulation of the seedling wrapping process, a comparative analysis was conducted to evaluate the number of juvenile mussels attached and their movement distances when exposed to contaminated old ropes versus uncontaminated new ropes. The findings indicated that the old ropes markedly diminished the attachment rate of juvenile mussels and heightened their movement distances. In particular, juvenile mussels utilizing old ropes exhibited a final attachment rate of 15.0% and an average movement distance of 0.86 cm, whereas those using new ropes achieved a final attachment rate of 96.7% with an average movement distance of 0.26 cm. Further inspection found that heavy metals and PAHs were present in the old rope, among which the concentrations of Zn (17.127 μg/g) and Pb (22.905 μg/g) in heavy metals were high, and the concentrations of Phe (5.53 μg/kg), Fla (6.35 μg/kg), and Pyr (5.17 μg/kg) in PAHs exceeded the detection limits, which were the main source of pollution. This research underscores the potential risk that heavy metal and PAHs contamination pose to the health of juvenile mussels and the profitability of aquaculture, emphasizing the critical need for the regular replacement of clean ropes.

Insight into the correlation of key taste substances and key volatile substances from shrimp heads at different temperatures

This study aimed to investigate taste substances of shrimp heads stored at 20 °C, 4 °C, -3 °C, and - 18 °C, and the correlation between taste substances and 25 key volatile substances. Notably, samples stored at 20 °C showed significant changes in bitter amino acids and hypoxanthine, and quickly deteriorated. Samples stored at 4 °C for 14 d or - 3 °C for 30 d facilitated the development of umami amino acids, sweet amino acids, and IMP. Furthermore, samples stored at -18 °C for 30 d demonstrated no significant changes in taste profile. Changes in taste substances through quantitative analysis were consistent with changes in taste profile through e-tongue analysis. Based on the results of O2PLS (VIP > 1), Cys, Arg, Glu, Ser, Val, Ala, Ile, ADP, and IMP were correlated with 25 key volatile substances. This study provides fundamental data for the storage, transportation, and value-added utilization of shrimp heads.

Effects of different thermal sterilization conditions on the quality of ready-to-eat shrimp based on specific sterilization intensity

The effects of different thermal sterilization conditions on the quality and digestibility of ready-to-eat (RTE) shrimp were investigated. Compared with the high-temperature (121 °C) and short-time (6 min and 8 min) sterilization, the low-temperature (110 and 115 °C) and long-time (>20 min) sterilization significantly promoted the Maillard and browning reactions and changed the color of the RTE-shrimp. The high sterilization temperature promoted shrimp protein oxidation, resulting in increased carbonyl group, disulfide bond, and free radical content, while the free sulfhydryl group content decreased. This oxidation and tissue destruction at high temperature led to reduced texture properties and altered water distribution within the shrimp's muscles. However, sterilized shrimp exhibited superior digestive properties in an in vitro simulated digestion experiment. High-temperature and short-time sterilization is more effective in mitigating the quality deterioration of RTE-shrimp compared to low-temperature and long-time sterilization.

Improving the texture attributes of squid meat (sthenoteuthis oualaniensis) with slight oxidative and phosphate curing treatments

This study aimed to improve the pasty texture of squid meat by oxidative and phosphate curing (OPC) treatment, and elucidate the underlying mechanism. The shear force, springiness, weight gain, water-holding capacity (WHC), color and sensory evaluation of squid meat samples treated with a mild OPC approach (OPC_2, 10 mM H2O2 solution with complex phosphate solution) were significantly improved. However, the samples subjected to over-oxidized (20 and 30 mM H2O2 solution with complex phosphate solution) treatment did not obtain favorable outcomes. Microstructure analysis revealed that muscle fibers aggregated after moderate OPC treatments, leading to an increased spacing between muscle fiber bundles. This gap facilitated a more uniform distribution and restriction of water, according to low-field nuclear magnetic resonance (LF-NMR) results. The results from in vitro simulated oxidation of myofibrillar proteins (MPs) demonstrated that increased H2O2 led to formation of carbonyl groups and decreased sulfhydryl groups, and even secondary structure changes, according to fourier transform infrared spectroscopy (FT-IR). Particle size, zeta potential and sodium dodecyl sulfate-polyacryl amide gel electrophoresis (SDS-PAGE) results showed that oxidation caused protein aggregation into larger molecules. This study presents a novel approach to improve pasty texture of squid meat.

Suanyu fermentation strains screening, process optimization and the effect of thermal processing methods on its flavor

Suanyu is a famous traditional fermented aquatic food in south China. However, the quality of Suanyu is unstable due to natural fermentation based on the environment. This work screened suitable microbial fermenters (Enterococcus rivorum and Enterococcus lactis) from traditional fermented fish and optimized a suitable fermentation process. Effects of different fermentation (natural and mixed starters fermentation) and thermal treatments (microwave, frying and roasting) on the flavor of Suanyu were investigated. Compared to the natural fermentation group, the TVB-N content (31.5 mg/100 g) was lower, the total acidity (5.12 g/kg) and flavor compounds content were richer in the mixed starters fermentation group (P < 0.05). But there was no significant difference in histamine content (P > 0.05). The roasting treatment group contained higher contents of free amino acids, organic acids, nucleotides and richer key aroma components. The electronic nose was able to distinguish between the differently treated samples. The sensory evaluation result showed that roasted and fried samples had a more acceptable flavor and color. This work will provide a theoretical reference for the standardized production of Suanyu and the development of pre-cooked products.