The Effect of Sodium Chloride on the Physicochemical and Textural Properties and Flavor Characteristics of Sous Vide Cooked Duck Meat.

This study was conducted to evaluate the effect of salt brining process parameters (salt concentration 0-15%, brining time 4-12 h, brining temperature 4-20 °C) on the quality of sous vide cooked duck meat by a single factor combined with response surface methodology (RSM). The sensory evaluation, physicochemical indexes (color, weight loss, NaCl content, TBARS value, and texture properties), and flavor characteristics were analyzed. The sensory overall mean score was applied as the evaluation index to optimize the brining conditions by RSM, and the optimum results contained a salt concentration of 11.69%, a brining temperature of 7.35 °C, and a brining time of 8.03 h. Under these conditions, the sensory overall mean score of duck meat was 8.59, with a relatively higher a* value and moderate NaCl content. GC-MS and odor activity value (OAV) results indicated that salt brining treatment significantly promoted the formation of the major odorants in duck meat, including pentanal, heptanal, octanal, (E)-2-nonenal, cis-4-decenal, decanal, 2,4-decadienal, (E,E)-2,4-decadienal, 1-heptanol, and 2-methyl-3-octanone, but decreased the content of hexanal, (E)-2-octenal, nonanal, (E,E)-2,4-nonadienal, 1-octen-3-ol, and 1-octen-3-one. 5'-nucleotides in duck meat were significantly increased after brining treatment. Therefore, salt brining treatment could be regarded as an efficient way to improve the sensory, aroma, and taste quality of sous vide cooked meat.

Effects of Drying Methods on Taste Components and Flavor Characterization of Cordyceps militaris.

The influences of four drying methods (hot air drying (HAD), vacuum freeze drying (VFD), vacuum drying (VD) and intermittent microwave combined with hot air drying (MW-HAD)) on the taste profile and flavor characteristic of Cordyceps militaris were investigated. MW-HAD samples had the highest levels of umami taste 5'-nucleotides, bitter taste amino acids, and equivalent umami concentration (EUC) value. The aroma fingerprints and differences of dried Cordyceps militaris were established by GC-MS with odor activity values (OAVs) and GC-IMS with principal component analysis (PCA). GC-MS data showed that the predominant volatiles of dried samples were aldehydes, alcohols, and ketones. VFD samples had the highest amount of total aroma compounds and C8 compounds. Moreover, 21 aroma-active components (OAVs ≥ 1) were the main contributors to the flavor of dried Cordyceps militaris. The OAVs of 1-octen-3-one and 3-octanone associated with mushroom-like odor in VFD were significantly higher than other samples. Furthermore, a significant difference in flavor compounds of four dried samples was also clearly demonstrated by GC-IMS analysis with PCA. GC-IMS analysis revealed that VFD samples had the most abundant flavor compounds. Overall, MW-HAD was an effective drying method to promote umami taste, and VFD could superiorly preserve volatiles and characteristic aroma compounds in dried Cordyceps militaris.