Meat Science最新文献

Belly is a widely consumed pork product with very variable properties. Meat industry needs real-time quality assessment for maintaining superior pork quality throughout the production. This study explores the potential of using visible and near-infrared (VNIR,386-1015 nm) spectral imaging for predicting firmness, fatness and chemical compositional properties in pork belly samples, offering robust spectral calibrations. A total of 182 samples with wide variations in firmness and compositional properties were analysed using common laboratory analyses, whereas spectral images were acquired with a VNIR spectral imaging system. Exploratory analysis of the studied properties was performed, followed by a robust regression approach called iterative reweighted partial least-squares regression to model and predict these belly properties. The models were also used to generate spatial maps of predicted chemical compositional properties. Chemical properties such as fat, dry matter, protein, ashes, iodine value, along with firmness measures as flop distance and angle, were predicted with excellent, very good and fair models, with a ratio prediction of standard deviation (RPD) of 4.93, 3.91, 2.58, 2.54, 2.41, 2.53 and 2.51 respectively. The methodology developed in this study showed that a short wavelength spectral imaging system can yield promising results, being a potential benefit for the pork industry in automating the analysis of fresh pork belly samples. VNIR spectral imaging emerges as a non-destructive method for pork belly characterization, guiding process optimization and marketing strategies. Moreover, future research can explore advanced data analytics approaches such as deep learning to facilitate the integration of spectral and spatial information in joint modelling.

The effects of cauliflower treated with atmospheric cold plasma (ACP), as a natural nitrite source, on the curing of ground ham and nitrosamine formation were investigated. Ground ham was prepared using sodium nitrite and ACP-treated cauliflower powder (PTCP) to achieve initial nitrite concentrations of 60 and 100 mg/kg, respectively. ACP treatment generated nitrite in cauliflower but significantly reduced the antioxidant activity (P < 0.05). As a nitrite source, PTCP had similar effects as sodium nitrite in the development of cured color in ground ham, with a comparable residual nitrite content (P ≥ 0.05). Three nitrosamines, N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), and N-nitrosopyrrolidine (NPYR), were detected in ground ham. NPYR formation was significantly lower in ground ham treated with PTCP at an initial nitrite concentration of 100 mg/kg (P < 0.05). Therefore, the use of a natural nitrite source manufactured through ACP treatment can prospectively achieve suitable curing efficiency while simultaneously suppressing nitrosamine formation.

The objective of this study was to evaluate and improve the prediction models of the AutoFOM III and FOM II apparatuses (Frontmatec Group, Denmark) used to estimate the lean meat percentage (LMP) of pig carcasses in Belgium, since the current models underestimate the pig carcasses with a LMP higher than 66 %. Non-linearity in the backfat thickness (BT) parameters was identified as the main reason for this bias in prediction. Box-Cox transformation of the parameters R2P10, R2P8 and R2P4 from AutoFOM III allowed to lower the root mean squared error of prediction (RMSEP) of the model from 1.72 to 1.59, while simultaneously removing the bias of the high LMP carcasses. For the FOM II apparatus, there was no effect of the transformation of the only BT parameter on the RMSEP (2.15 before and 2.14 after transformation) and on the bias. Next to the transformation, it was investigated whether adding other information about the carcasses could also improve the RMSEP of the prediction models. The parameters hot carcass weight, carcass length, ham width, ham angle and sex were added to the original models without transformation and lowered the RMSEP from AutoFOM III and FOM II to 1.55 and 1.83 respectively. Finally, the best results were found by combining the Box-Cox transformation and adding other carcass parameters, resulting in RMSEP values of 1.50 and 1.82 for AutoFOM III and FOM II respectively, on top of the removal of the high LMP bias.

Implications

Accurate estimation of the lean meat percentage of pig carcasses is of great economic importance for the pig production and slaughtering sector, so every opportunity to increase precision should be seized. This study shows that the current linear prediction models can be improved by taking into account non-linearity, depending on the device. An even larger increase in precision can be achieved by adding carcass information that is currently not measured or not linked to the classification device but that is partly already available at the slaughterline.

Consumer demand for tastier and higher-quality pork is increasing. Probiotics have been reported to improve meat quality, but the species of probiotics are limited, and efficacy is discrete. This study investigated the effects of dietary Brevibacillus laterosporus BL1 (live and heat-killed form) supplementation on the meat quality of finishing pigs. Results revealed that both live and heat-killed B. laterosporus BL1 supplementation increased pH_24h and decreased drip loss (P < 0.05) compared to the control group (CON). Moreover, compared to the CON group, heat-killed B. laterosporus BL1 supplementation exhibited a stronger ability to improve meat quality (redness, shear force, inosine monophosphate, and intramuscular fat content, P < 0.05), antioxidant capacity, and free amino acid profiles of longissimus thoracis (LT) than live bacteria without impairing porcine growth performance. Further, heat-killed B. laterosporus BL1 supplementation favored up-regulating the expression of genes related to oxidative-type fiber in LT (P < 0.05). Proteomic analysis confirmed that Gene Ontology items related to oxidative metabolism were subsequently enriched with heat-killed B. laterosporus BL1 treatment in LT (P < 0.05). Overall, dietary heat-killed B. laterosporus BL1 supplementation may improve the meat quality of finishing pigs, which provides application guidance for B. laterosporus BL1 in producing higher-quality pork.

Protein grass hay (PGH) was used as a new feed source for lambs to study its effect on fattening performance and meat quality. Fifty-six male lambs were allotted to four experimental groups and fed for eight weeks either alfalfa hay (AH)-based diet (control) or diets in which AH was replaced with 33 %, 66 %, or 99 % PGH. The inclusion of PGH did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio, or carcass weight. Moreover, substituting AH with PGH at any level did not influence the ruminal fermentation or serum biochemical parameters, meat color, water holding capacity, shear force, or amino acid profile. However, relative liver weight was increased with 66 % substitutions. Furthermore, replacing 99 % AH with PGH decreased the meat's pH at 24 h. Higher levels of C18:3n-3, C20:5n-3, and total n-3 PUFA and a lower ratio of n-6: n-3 PUFA were also observed in meat from lambs fed PGH at 99 %. These findings suggest that PGH could be incorporated into the lamb's diet up to 99 % without compromising fattening performance and body health while improving their meat n-3 PUFA deposition.

Machine learning classification approaches were used to discriminate a fishy off-flavour identified in beef with health-enhanced fatty acid profiles. The random forest approach outperformed (P < 0.001; receiver operating characteristic curve: 99.8 %, sensitivity: 99.9 % and specificity: 93.7 %) the logistic regression, partial least-squares discrimination analysis and the support vector machine (linear and radial) approaches, correctly classifying 100 % and 82 % of the fishy and non-fishy meat samples, respectively. The random forest algorithm identified 20 volatile compounds responsible for the discrimination of fishy from non-fishy meat samples. Among those, seven volatile compounds (pentadecane, octadecane, γ-dodecalactone, dodecanal, (E,E)-2,4-heptadienal, 2-heptanone, and ethylbenzene) were selected as significant contributors to the fishy off-flavour fingerprint, all being related to lipid oxidation. This fishy off-flavour fingerprint could facilitate the rapid monitoring of beef with enhanced healthy fatty acids to avoid consumer dissatisfaction due to fishy off-flavour.

Meat processing has a long history and involves a wide and ever-increasing range of chemical and physical processes, resulting in a heterogeneous food category with a wide variability in nutritional value. Despite the known benefits of meat consumption, observational epidemiological studies have shown associations between consumption of red and processed meat - but not white meat - and several non-communicable diseases, with higher relative risks for processed meat compared to unprocessed red meat. This has led global and regional nutrition and health organisations to recommend reducing consumption of unprocessed red meat and avoiding processed meat. A plethora of potentially implicated hazardous compounds present in meat or formed during processing or gastrointestinal digestion have been reported in the literature. However, our mechanistic understanding of the impact of meat consumption on human health is still very incomplete and is complicated by the simultaneous occurrence of multiple hazards and interactions with other food compounds and host factors. This narrative review briefly discusses hazards, risks and their assessment in the context of dietary guidelines. It is argued that more mechanistic studies of the interactive effects of meat products with other foods and food compounds in different dietary contexts are needed to refine and increase the evidence base for dietary guidelines. Importantly, the great diversity in the composition and degree of processing of processed meats should be better understood in terms of their impact on human health in order to develop a more nuanced approach to dietary guidelines for this food category.

This study aimed to investigate the impact of feeding patterns on the production performance, lipo-nutritional quality, and gut microbiota of Sunit sheep. A total of 24 sheep were assigned to two groups: confinement feeding (CF) and pasture feeding (PF) groups. After 90 days, the CF group exhibited significantly increased average daily gain, carcass weight, backfat thickness, and intramuscular fat content of the sheep, whereas the PF group showed significantly increased pH_24h and decreased L^∗ value and cooking loss of the longissimus lumborum (LL) muscle (P < 0.05). In the PF group, the contents of linoleic, α-linolenic, and docosahexaenoic acids were considerably higher and the n-6/n-3 polyunsaturated fatty acid ratio was significantly lower (P < 0.05). Furthermore, the triglyceride, cholesterol, and nonesterified fatty acid levels in the serum of the CF group significantly increased, whereas the enzyme contents of fatty acid synthase (FASN) and hormone-sensitive lipase (HSL) in the LL muscle of the PF group were markedly elevated (P < 0.05). The PF group also showed altered expression of lipid metabolism-related genes, including upregulated FASN, HSL, fatty acid binding protein 4 (FABP4), and peroxisome proliferator–activated receptor γ coactivator 1α (PGC-1α) (P < 0.05). Meanwhile, differences were observed in the abundance of key bacteria and microbiota functions between the groups. Correlation analysis revealed that production performance and lipid metabolism may be related to the differential effects of bacteria. In conclusion, the transition in the feeding patterns of Sunit sheep caused changes in the gut microbial community and lipid metabolism level in the muscle as well as differences in fat deposition and meat quality.

Pork eating quality is affected by various factors. In this study, Longissimus thoracis et lumborum (LTL) and Semimembranosus (SM) muscles from seven genetic lines (PM-LR – Pure maternal, Landrace-type; PM-LW – Pure maternal, Large White-type; PM-D – Pure maternal, Duroc-type; PT-D – Pure terminal, Duroc-type; PT-LW – Pure terminal, Large White-type; PT-LR - Pure Terminal, Landrace-type; Comp-P × LW × D - Composite Terminal – Pietran × Large white × Duroc) were analyzed for pH, intramuscular fat (IMF) content, and collagen content and solubility. A consumer sensory test using check-all-that-apply (CATA) and biometric approaches was also conducted. The results showed that the IMF content of line PM-D was the highest (P = 0.004), while line PT-LW received the highest score in tenderness, liking of flavor, purchase intent, and quality grading (P < 0.05). Line PM-LR and PT-LR showed the lowest IMF content and were least preferred by consumers. Compared to LTL, SM showed higher pH, collagen solubility, and sensory scores in tenderness, juiciness, liking of flavor, and overall liking (P < 0.05). Different muscles and lines were associated with different CATA terms but not with differences in consumer emotional responses. pH positively influenced tenderness, juiciness, and overall liking (P < 0.05), but IMF and collagen had little effect. The flavor was the most important sensory attribute contributing to overall liking, followed by tenderness. Genetic line and muscle affected pork chemical properties and eating quality. The findings are important for the Australian pork industry to improve the eating quality of their products.

This study assessed the effect of boning processing method (hot vs. cold) on pork belly morphological and mechanical traits and the evolution of these traits during refrigerated storage postmortem (PM). A total of 14 crossbred pigs were slaughtered and their carcasses and bellies processed under two conditions: hot boning (n = 14, right sides of carcasses cut immediately after slaughter) and cold boning (n = 14, left sides of carcasses cut 24 h PM). Morphological and mechanical evaluations were made at 1-, 5-, 24- and 48-h PM on the hot-boned bellies, and at 24 and 48 h on the cold-boned ones. Compared to the cold-boned bellies, the hot-boned ones were shorter, wider and thicker (P < 0.01), with greater firmness (flop distance and angle) (P < 0.001) and cohesiveness (skin-fat separation) (P < 0.05 in the dorsal and central sections). At 48 h PM, hot-boned bellies had a thicker skin (P < 0.001) and softer subcutaneous fat in the dorsal-cranial and central sections (finger scores and compression textural test) (P < 0.05). Morphological and mechanical traits for hot-boned bellies confirmed an intense shortening and hardening (increased firmness and cohesiveness), and a slight yield loss from 1 to 24 h PM. From 24 to 48 h PM, there was a certain flattening in hot-boned bellies that was associated with a slight softening (reduced firmness). Although a larger sample may be needed to corroborate these findings, they demonstrate the impact of carcass processing method and refrigerated storage time on belly quality. This may be useful for the pork industry for obtaining the desired type of belly.