Amino acid and nucleotide contents and sensory traits of dry-cured products from pigs with different genotypes

Exploring the dietary strategies of phenylalanine: Improving muscle nutraceutical quality as well as muscle glycogen and protein deposition in adult grass carp (Ctenopharyngodon idella)

Muscle is the main edible part of bony fish. The purpose of this study was to investigate the influences of phenylalanine (Phe) on muscle quality, amino acid composition, fatty acid composition, glucose metabolism, and protein deposition in adult grass carp. The diets at 2.30, 4.63, 7.51, 10.97, 13.53, and 17.07 g/kg Phe levels were fed for 9 weeks. The results manifested that Phe (10.97-13.53 g/kg) increased the pH of the fillets and decreased muscle cooking loss and lactic acid content; Phe (7.51-17.07 g/kg) improved the composition of the fillets in terms of flavor (free) amino acids, bound amino acids (especially EAA), and fatty acids (especially EPA and DHA); Phe (7.51-13.53 g/kg) increased muscle glycogen content (possibly related to the AMPK signaling pathway) and muscle protein deposition (possibly related to IGF-1/4EBP1/TOR and AKT/FOXOs signaling pathways). In conclusion, a diet with appropriate Phe levels could improve fillet quality.

LC-MS/MS-based metabolomics and sensory evaluation characterize metabolites and texture of normal and spoiled dry-cured hams

The spoiled dry-cured ham commonly shows unpleasant taste and odour. To deepen the understanding in the formation mechanism of unpleasant taste in spoiled ham, sensory attributes, texture parameters, protein degradation, metabolites were investigated between normal and spoiled hams; the relationship between the sensory quality and metabolites of dry-cured ham was further evaluated by partial least square discriminant analysis (PLS-DA). The scores of richness and overall acceptance were significantly lower in spoiled ham, and more than 12.5-fold values in adhesiveness were found in spoiled ham than normal ham. Myofibrillar proteins including actin, troponin-T and myosin light chain showed excessive degradation in spoiled ham. Forty-two kinds of metabolites mainly derived from protein degradation were identified by LC-MS/MS, and amino acid derivatives and oligopeptides were the key components to distinguish spoiled and normal hams demonstrated by PLS-DA. Purine metabolism, pyrimidine metabolism and protein degradation were the main metabolism pathways in spoiled ham.

Effects of Dry- and Wet-ageing on Flavor Compounds and Eating Quality of Low Fat Hanwoo Beef Muscles

The present study aimed at investigating the effects of dry- and wet-aging methods on flavor compounds and sensory properties of low fat Hanwoo beef muscles. All the beef samples were obtained from 2-grade carcasses of Hanwoo cows. The beef samples used in the dry- and wet-aging methods were prepared in the forms of quarter beef (bone-in) and cuts (boneless), respectively. The dry-aging was carried out at 2°C-4°C and humidity of 65%-85%, while the wet-aging was done at 1°C for 0, 20, 40, and 60 d. At each aging time, three muscles: longissmus thoracis (LT), glutaeusmedus (GM) and semimembranosus (SM) were taken from the corresponding quarters and cuts, and used for the flavor compounds and sensory analyses. Results showed that both aging methods significantly increased the concentrations of flavor compounds and total amount of all classes of the flavor compounds as the aging time increased (p<0.05). In the dry-aging method, the GM and SM muscles presented significantly higher total amounts of pyrazines and sulfur-containing compounds compared to the LT muscle (p<0.05). Both the aging methods improved the eating quality attributes, indicating by increased scores of sensorial attributes with increased aging time for all the muscles studied (p<0.05). However, compared to the wet-aging, the dry-aging method resulted in significantly higher scores of tenderness and flavor for the GM and SM muscles after 40 to 60 d. Thus, postmortem aging, especially the dry-aging method could be used to improve eating quality attributes (tenderness and flavor) of low fat beef muscles such as GM and SM.

Physicochemical and sensory characteristics of dry-cured loin made from pigs fed Allium hookeri added whey powder and sensory trait evaluation using electronic tongue

The aim of this study was to determine the effect of dietary supplementation with Allium hookeri (A. hookeri) added whey powder on the physicochemical characteristics of dry-cured loin (CON, basal diet; AH, addition of 1% A. hookeri; AHW, addition of 0.5% A. hookeri and 4% whey powder) during manufacturing (pre- and post-salting, drying and ripening process) and analyse their sensory characteristics using electronic tongue. Crude fat and weight yield of AH were higher (P &lt; 0.05) than those of CON. The AH inhibited (P &lt; 0.05) lipid oxidation and the reduction of redness during manufacturing. The percentage of some free amino acids (tyrosine, methionine, phenylalanine, isoleucine and leucine) in AHW was higher (P &lt; 0.05) compared with those in CON. Monounsaturated fatty acid composition was the highest (P &lt; 0.05) in AHW. Sensory evaluation by panellists did not show significant differences among the three groups (CON, AH and AHW). However, the richness of AH and AHW was significantly higher compared with that of CON based on electronic tongue analysis. Taken together, these results revealed that AH supplementation with whey powder had higher oxidative stability and enhanced dry-cured loin quality.

Metabolomic Profiling as a Possible Reverse Engineering Tool for Estimating Processing Conditions of Dry-Cured Hams

Dry-cured hams are popular among consumers. To increase the attractiveness of the product, objective analytical methods and algorithms to evaluate the relationship between observable properties and consumer acceptability are required. In this study, metabolomics, which is used for quantitative profiling of hundreds of small molecules, was applied to 12 kinds of dry-cured hams from Japan and Europe. In total, 203 charged metabolites, including amino acids, organic acids, nucleotides, and peptides, were successfully identified and quantified. Metabolite profiles were compared for the samples with different countries of origin and processing methods (e.g., smoking or use of a starter culture). Principal component analysis of the metabolite profiles with sensory properties revealed significant correlations for redness, homogeneity, and fat whiteness. This approach could be used to design new ham products by objective evaluation of various features.

Effects of Ripening Conditions on the 'Lomo embuchado' Sausage Quality

The objective of this study was to investigate the effects of two different ripening durations, with, or without adding rosemary powder, on Lomo embuchado (LEO) sausage quality. All LEOs were ripened for two different durations, 45 or 60 d, with, or without the addition of rosemary powder, as follows: 1) LEO ripened for 45 d (LER45), 2) LEO ripened for 60 d (LER60), 3) rosemary LEO ripened for 45 d (RLE45), and 4) rosemary LEO ripened for 60 d (RLE60). Significant differences were observed in both moisture and ash content, with higher moisture and less ash content in LER45 (p<0.05). No trend was shown in the crude protein content of the four different treatments, but significantly low protein content was shown only in RLE45 (p<0.05). Ripening for 45 d improved the lightness, yellowness, and water activity of LEOs (p<0.05). However, ripening duration together with rosemary powder addition had no significant effects on redness (p>0.05). The LER45 generated significantly improved chewiness, gumminess, and hardness, as compared to both LER60 and RLE60 (p<0.05). In conclusion, the results suggest that ripening for 45 d seems to enhance LEO quality, but that rosemary powder addition may not be required to develop good LEO quality.