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Sous-vide (SV), as a mild processing technique, exhibits some potential for keeping the original flavor of oyster. The dynamic changes mechanism of flavor and taste in oyster during SV processing (0–30 min/75 °C) were investigated. SV processing for 10–15 min improved the umami of oysters, likely due to the increase in adenosine monophosphate and glutamate, while processing for 20–30 min resulted in a significant loss of "grassy" flavor. GC–MS and GC-IMS analysis showed that the loss of short-chain aldehydes, such as (E)-2-pentenal, (E)-2-hexenal and (E, E)-2,4-hexadienal may be related to the weakening of the "grassy" flavor, and the formation of 2,3-diethylpyrazine and octanal produced a "cooked" and "fatty" flavor. The analysis of lipidomics indicated that phosphatidylethanolamine, lysophosphatidylcholine and sphingomyelin, synthesized mainly through glycerophospholipid and sphingolipid metabolism, were key precursors for aldehyde formation. This study provides a theoretical basis for controlling the flavor quality of oyster during mild processing. [Display omitted] • Short-term sous-vide processing improved the umami of oysters. • The optimal sous-vide processing time for oysters was 15 min at 75 °C. • Aldehyde compounds have a significant impact on the "grassy" and "cooked" flavor of oysters. • PE, LPC, and SM were key precursors for the formation of aldehydes in oysters. [ABSTRACT FROM AUTHOR]

The study determines the antioxidant properties of methanol vegetable extracts from raw vegetables, conventionally cooked vegetables and sous-vide. In the research, two methods were used: free radical scavenging DPPH (µM Trolox) and the reduction of Fe 3+ to Fe 2+ – FRAP (µM Fe 2+ ). Antioxidative properties for raw vegetables were obtained with the range of 7.47–235 (µM Trolox/100 g of vegetables) and 2.66–103 (µM Fe 2+ /100 g of vegetables), for vegetables after the conventional cooking process 6.15–657 (µM Trolox/100 g of vegetables) and 3.03–99.9 (µM Fe 2+ /100 g of vegetables), for vegetables after the sous-vide process 4.45–648 (µM Trolox/100 g of vegetables) and 3.06–99.9 (µM Fe 2+ /100 g of vegetables). For some vegetables, an increase in the antioxidative potential was observed as a result of cooking processes; however, it was much higher for the sous-vide technique. All results were subjected to a one-way analysis of variance (ANOVA) and, if significant differences were revealed, the POST-HOC Duncan test was used (α = 0.05). [ABSTRACT FROM AUTHOR]

Abstract: The present study assessed the effect of high pressure–temperature (HPT) processing on the levels of three polyacetylenes in carrot disks immediately after processing in comparison to sous-vide processing. The degradation kinetics of these compounds following processing at HPT was also investigated. The highest pressure–temperature combination which gave maximum retention during the time 10–30min, for falcarinol it was 400MPa, at 50 and 60°C for 10min; for falcarindiol it was 400MPa, at 50°C for 10min and for falcarindiol-3-acetate was 400MPa, at 50°C for 10min, respectively. Falcarindiol-3-acetate was found to be most barosensitive and falcarindiol was found to be most thermosensitive of the three polyacetylenes studied. When compared with sous-vide (SV) processed carrot disks, HPT processed samples showed higher retention of polyacetylenes. The changes in the levels of polyacetylenes during HPT treatment were adequately described by Weibull model function. [Copyright &y& Elsevier]

Abstract: The effects of desalting and boiling, with or without vacuum-packaging, on the composition of the subcutaneous adipose tissue of dry-cured pork forelegs were investigated. The adipose tissue contained 7.1% water and 91.0% lipids. The main fatty acids in glycerides (about 89% of total lipids) were oleic (39.6%), palmitic (23.9%), linoleic (13.7%) and stearic (12.6%) acids. The main fatty acids in free fatty acids (about 11% of total lipids) were oleic (36.0%), linoleic (28.4%) and palmitic (13.1%). The culinary treatment (desalting and boiling) caused significant decreases in dry matter and lipid contents. These decreases were not as great in vacuum-packaged samples because the lipid losses were prevented during the boiling stage. No significant changes in lipid fraction proportions (glycerides and free fatty acids) were observed. The samples boiled with vacuum-packaging showed higher contents of polyunsaturated fatty acids than did the samples boiled without vacuum-packaging. [Copyright &y& Elsevier]

Abstract: The effects of desalting and boiling, with or without vacuum packaging, on the composition (mainly in relation to lipids) of the muscles of deboned pieces of dry-cured pork forelegs were investigated. The muscles of boiled, desalted, dry-cured foreleg pieces showed lower ash, chloride, nitrates and nitrites contents and higher protein contents than those of dry-cured forelegs. No significant changes were observed in lipid content and in lipid fraction proportions (glycerides, phospholipids and free fatty acids). The culinary treatment (desalting and boiling) caused a decrease of thiobarbituric acid values and an increase in polyunsaturated fatty acids proportions of the three fractions (glycerides, phospholipids and free fatty acids), especially at C-18:2 and C-20:4. Only the ash contents were significantly different between samples boiled with and without vacuum packaging. [Copyright &y& Elsevier]

• Taste of two-stage sous-vide beef assessed by electronic tongue. • Non-volatile compounds affected at different cooking conditions. • AMP, IMP, GMP have synergistic effect with aspartic and glutamic acid. • High umami taste can be perceived at 70 °C. • Lipid and protein oxidation were less important for taste traits determination. The influence of temperature–time combinations on non-volatile compound and taste traits of beef semitendinosus muscles tested by the electronic tongue was studied. Single-stage sous-vide at 60 and 70 °C (6 and 12 h), and two-stage sous-vide that sequentially cooked at 45 °C (3 h) and 60 °C (either 3 or 9 h) were compared with traditional cooking at 70 °C (30 min). Umami was better explained in the given model of partial least squares regression than astringency, sourness, saltiness, bitterness, and richness. Sous-vide at 70 °C for 12 h characterized the most umami, likely adenosine-5′-monophosphate (AMP) and guanosine-5′-monophosphate (GMP) as significant contributors. Two-stage sous-vide projected higher histidine, leucine, inosine, and hypoxanthine with the astringent and sour taste significant after 6 and 12 h cooking, respectively. Equivalent umami concentration (EUC) between umami amino acids and umami nucleotides showed a strong relationship to umami taste assessed by the electronic tongue. [ABSTRACT FROM AUTHOR]