Are shear force methods adequately reported?

Empowering informed choices: How computer vision can assists consumers in making decisions about meat quality

Consumers often find it challenging to assess meat sensory quality, influenced by tenderness and intramuscular fat (IMF). This study aims to develop a computer vision system (CVS) using smartphone images to classify beef and pork steak tenderness (1), predicting shear force (SF) and IMF content (2), and performing a comparative evaluation between consumer assessments and the method's output (3). The dataset consisted of 924 beef and 514 pork steaks (one image per steak). We trained a deep neural network for image classification and regression. The model achieved an F1-score of 68.1 % in classifying beef as tender. After re-categorizing the dataset into 'tender' and 'tough', the F1-score for identifying tender increased to 76.6 %. For pork loin tenderness, the model achieved an F1-score of 81.4 %. This score slightly improved to 81.5 % after re-categorization into two classes. The regression models for predicting SF and IMF in beef steak achieved an R2 value of 0.64 and 0.62, respectively, with a root mean squared prediction error (RMSEP) of 16.9 N and 2.6 %. For pork loin, the neural network predicted SF with an R2 value of 0.76 and an RMSEP of 9.15 N, and IMF with an R2 value of 0.54 and an RMSEP of 1.22 %. In 1000 paired comparisons, the neural network correctly identified the more tender beef steak in 76.5 % of cases, compared to a 46.7 % accuracy rate for human assessments. These findings suggest that CVS can provide a more objective method for evaluating meat tenderness and IMF before purchase, potentially enhancing consumer satisfaction.

The quality and nutritional value of beef from Angus steers fed different levels of humate (K Humate S100R)

This study compared the effect of four levels of K Humate S100R (potassium humate) supplementation on the quality, shelf-life, and nutritional properties of beef. Angus steers (n = 40) were individually housed and fed either 0, 35, 70, or 140 g K Humate S100R/animal/day for 100 days, following a 30 day adjustment period. The steers were slaughtered at the completion of the feeding study. The left m. longissimus lumborum (LL) was collected at 24 h post-mortem and aged for either 2 or 6 weeks before analysis. K Humate S100R supplementation did not affect beef drip loss, cooking loss, shear force, sarcomere length, ultimate pH, intramuscular fat content, or total volatile basic nitrogen concentrations (P > 0.05). Steers supplemented with 70 g/day K Humate S100R produced beef with higher a* values on Days 1 and 3 of retail display (P < 0.05). Beef mineral composition was unchanged by K Humate S100R supplementation (P > 0.05), but there were minor changes to the fatty acid profile. Specifically, the ratio of omega-6 to omega-3 (P < 0.05) and C20:2n-6 concentrations (P < 0.05) increased with supplementation level. Together, these results demonstrate no detrimental effects on beef quality and shelf-life as a result of K Humate S100R supplementation.

High-pressure processing and modified atmosphere packaging combinations for the improvement of dark, firm, and dry beef quality and shelf-life

This study investigated the effects of high-pressure processing (HPP) and modified atmosphere packaging (MAP) on 'dark, firm, and dry' (DFD) beef. To optimize the HPP, beef steaks (n = 180) were first processed at different pressures (0.1, 200, 300, 400, 500 MPa). It was found that 400 MPa enhanced DFD beef color and shelf-life. This optimized HPP (400 MPa) was combined with 3 MAP formulations, in a second study (40, 60, or 80% O₂-MAP), to determine their effect on DFD beef steaks. HPP (400 MPa) combined with MAP improved DFD beef L* and a*, color scores, and delayed discoloration (P < 0.01). Total plate counts for DFD beef held under 60% O₂-MAP was ≤6 log₁₀ CFU/g, even after 14 d of chilled storage. These same samples had shear force and TBARS values significantly lower than observed for DFD beef held under 80% O₂-MAP. HPP (400 MPa) combined with 60% O₂-MAP is recommended to improve DFD beef quality and shelf-life.

Forage based diet as an alternative to a high concentrate diet for finishing young bulls - Effects on growth performance, greenhouse gas emissions and meat quality

Two groups of 8 individually housed young crossbred-bulls, in the finishing period, were used to test the effect of a Total Mixed Ration diet with high forage content (54% DM), low starch content (14% DM), supplemented with sunflower seeds (10% DM) (HFS) on growth performance, carcass and meat quality, fatty acid profile and carbon footprint, with reference to a conventional concentrate-based (90% DM) (Control) diet. The experiment lasted 64 days before slaughter. During the experiment, feed intake was monitored daily and live weight every 14 days. Individual CH₄ emissions were assessed at 16-days intervals, using a GreenFeed for Large Animal unit. Feed intake and feed conversion ratio were higher for HFS diet, but average daily weight gain and feeding costs were similar for the two diets. Dressing percentage was reduced with HFS diet. The HFS increased redness, yellowness and Chroma of subcutaneous fat, but did not compromise commercial value of the carcasses. Meat colour, shear force, or sensory parameters were not affected by diet. The HFS diet allowed a healthier FA profile, due to the higher proportions of 18:3n-3, t11-18:1 and c9,t11-18:2 and the lower proportion of t10-18:1. The HFS diet did not reduce the carbon footprint in the finishing period of young bulls, due to increased digestive CH₄ emissions. The results of this experiment showed that the HFS diet can be an alternative to the conventional diets used in finishing young-bulls. Although it may result in a slight reduction in animal performance, it has a strong impact on reducing dependence on inputs from outside the farm.

Efficient removal of dextran in sugar juice by immobilized α-dextranase from Chaetomium gracile

Dextran problem restricts the development of the sugar industry. Although the enzymatic treatment based on α-dextranase from Chaetomium gracile (α-dextranase (CG)) has been effective in solving this issue, the lack of immobilization products hinder its industrial applications. This research described a novel and suitable method to immobilize α-dextranase (CG). The purified α-dextranase (CG) was immobilized via cross-linking using modified chitosan as carriers. In addition, this study used a deep eutectic solvent that greatly improved the enzymatic properties of immobilized α-dextranase (CG). α-dextranase (CG) was immobilized by adding deep eutectic solvent (DES-IM-α-dextranase (CG)) showed better temperature tolerance and storage properties than free and ordinary immobilized counterparts. It can eliminate dextran by 59.71% in mixed sugarcane juice and 38.71% in clarified sugarcane juice. The achieved results were considerably better than those obtained using free and other immobilized enzymes. Altogether, these findings confirmed that DES-IM-α-dextranase (CG) displayed great potential in solving the dextran problem.

The use of conventional laboratory-based methods to predict consumer acceptance of beef and sheep meat: A review

Meat scientists often use objective, laboratory-based methods to understand the sensorial properties of red meat. These approaches are advantageous because of their reproducibility, low cost, rapid generation of data and technical ease - comparative to large scale consumer sensory panels. To enhance the value of these methods, effort has been applied to identify specific limits or thresholds that correspond to a consumer's acceptance or satisfaction with the quality of a meat product. From the literature, we observe there to be inconsistencies in these thresholds. This could stem from disparate laboratory methods, consumer panel procedures and demographics, the approach to statistical analysis, sample type and representativeness, and more. This paper aimed to review consumer thresholds, proposed in the literature, to provide insight into their validity and transferability to other studies. Investigations were limited to red meat (beef and sheep meat) and to non-spectroscopic methods that have been used to predict consumer acceptance of colour, tenderness, juiciness, flavour and overall liking.

Molecular signatures of beef tenderness: Underlying mechanisms based on integromics of protein biomarkers from multi-platform proteomics studies

Over the last two decades, proteomics have been employed to decipher the underlying factors contributing to variation in the quality of muscle foods, including beef tenderness. One such approach is the application of high-throughput protein analytical platforms in the identification of meat quality biomarkers. To broaden our understanding about the biological mechanisms underpinning meat tenderization across a large number of studies, an integromics study was performed to review the current status of protein biomarker discovery targeting beef tenderness. This meta-analysis is the first to gather and propose a comprehensive list of 124 putative protein biomarkers derived from 28 independent proteomics-based experiments, from which 33 robust candidates were identified worthy of evaluation using targeted or untargeted data-independent acquisition proteomic methods. We further provide an overview of the interconnectedness of the main biological pathways impacting tenderness determination after multistep analyses including Gene Ontology annotations, pathway and process enrichment and literature mining, and specifically discuss the major proteins and pathways most often reported in proteomics research.

Effect of different cooking methods on sensory quality assessment and in vitro digestibility of sturgeon steak

Sous vide can keep the nutritional properties and improve taste of food compared with other conventional methods. In addition, this method may reduce the risk of recontamination after cooking and during storage. The purpose of this paper was to study the effects of four cooking methods (steaming, microwaving, baking, and frying) on the sensory and digestibility on sturgeon steak pretreated by sous vide during the cold storage (0-25 days). The results showed that the digestibility of steaming and microwaving groups (range from 80.34% to 90.12%) significantly higher than that of the other treatment groups (p < .05); however, the overall acceptability of the two groups was lower. What more, the frying group has the highest acceptability and the lowest digestibility (range from 65.12% to 70.89%). The springiness (4.12-6.56 mm) and chewiness (1.75-3.12 mm) of the frying group were significantly higher than those of the other treatment groups, which was consistent with the results of scanning electron microscopy (SEM) that frying treatment group has a denser structure and smaller pores. With the prolonged refrigeration time, especially between 15 and 25 days, the volatile flavor components (nitrogen oxide, methane, and alcohol) and stagnant water (T21) were significantly decreased. Principal component analysis showed that the moisture content was the main factor affecting the overall acceptability and best consumption time of the sturgeon was within 15 days. Simulating the effects of home cooking conditions and refrigeration storage time on the quality of sturgeon steak provided a reference for consumers using similar products.

Understanding consumer liking of beef using hierarchical cluster analysis and external preference mapping

BACKGROUND

This study was conducted to assess whether there are differences in consumer liking of beef. Samples were collected from different groups and analyses were conducted, including quantitative descriptive analysis, consumer panels and instrumental analyses. Palatability traits, such as aroma liking, tenderness, juiciness, flavour liking and overall liking (OL), were rated by consumers.

RESULTS

Warner-Bratzler shear force was negatively associated with tender mouthfeel and consumer tenderness score. Cluster analysis identified four groups of clusters, which were described as 'easily pleased', 'bull beef liker', 'tender beef liker' and 'fastidious' consumers. Cluster group 2 awarded a higher score for bulls and located in a separate region on the external preference map.

CONCLUSION

External preference mapping showed the association between consumer liking of beef and sensory attributes. © 2019 Society of Chemical Industry.

Comparison of methods for measuring shear force and sarcomere length and their relationship with sensorial tenderness of longissimus muscle in beef

Slice shear force (SSF) and laser diffraction, considered faster methodologies, for measuring beef instrumental tenderness and sarcomere length, were compared with reference methodologies Warner-Bratzler shear force (WBSF) and phase contrast microscopy. Striploin samples (n = 74) were analyzed for pH, sarcomere length, instrumental tenderness, myofibrillar fragmentation index, and sensorial tenderness. Pearson's correlation measured the association of meat evaluation methods with residual analysis of the multivariate analysis of variance model. The n-dimensional profile to evaluated methods was presented by biplot to identify the behavior of the correlation between the methods (variables). There was moderate correlation between SSF and WBSF (r = .63; p < .01) and both presented moderate correlation with sensorial tenderness (r = - .62 and -.55, to SSF and WBSF, respectively; p < .01). However, WBSF was more efficient to classify samples as tender (68%) than SSF (47%), comparing with sensorial tenderness (80%). There was a moderate correlation for laser and microscopy for sarcomere length (r = .57; p < .01). Sarcomeres were shorter when measured by laser than microscopy. Either with low correlation coefficients, sarcomere measured by laser (r = .29; p < .05) presented higher correlation with sensorial tenderness than with microscopy (r = .22; p < .10). Results highlighted that SSF was faster and easier to run, while WBSF was more appropriate to classify samples by sensorial tenderness grades. Laser diffraction is more suitable to explain effects on tenderness; however, microscopy revealed results of sarcomere length that were more realistic, once laser can underestimate sarcomeres.

Statistical model choice including variable selection based on variable importance: A relevant way for biomarkers selection to predict meat tenderness

In this paper, we describe a new computational methodology to select the best regression model to predict a numerical variable of interest Y and to select simultaneously the most interesting numerical explanatory variables strongly linked to Y. Three regression models (parametric, semi-parametric and non-parametric) are considered and estimated by multiple linear regression, sliced inverse regression and random forests. Both the variables selection and the model choice are computational. A measure of importance based on random perturbations is calculated for each covariate. The variables above a threshold are selected. Then a learning/test samples approach is used to estimate the Mean Square Error and to determine which model (including variable selection) is the most accurate. The R package modvarsel (MODel and VARiable SELection) implements this computational approach and applies to any regression datasets. After checking the good behavior of the methodology on simulated data, the R package is used to select the proteins predictive of meat tenderness among a pool of 21 candidate proteins assayed in semitendinosus muscle from 71 young bulls. The biomarkers were selected by linear regression (the best regression model) to predict meat tenderness. These biomarkers, we confirm the predominant role of heat shock proteins and metabolic ones.

Using microwave cooking to evaluate tenderness and its relationship to sensory analysis

This study evaluated a microwave (Mw) cooking method for determining beef toughness using the Warner-Bratzler slice shear force (WBsSF) protocol. Longissimus thoracis muscles were aged for 1, 10, 19, and 28 days at 4C. They were then either cooked on a clam-shell grill until reaching an internal temperature of 72C, in a Mw for 100 s at maximum power (Mw100) or for 140 s at 60% of maximum power (Mw60). Cooking loss and shear force (SF) values were higher in Mw samples than in grilled ones. SF assessment by grill and Mw100 were able to discriminate tenderness by aging times in the same way as the sensory panel. The SF measured in a grilled sample had higher repeatability (R = .74) and correlation with sensory scores (r = -.79) than Mw100 (R = .61; r = -.62) and Mw60 (R = .51; r = -.53). Mw100 can be considered as an appropriate alternative for the WBsSF protocol. PRACTICAL APPLICATIONS: Tenderness is the most important attribute for consumers. Many studies have evaluated tenderness in meat and different protocols for cooking. This work was intended to optimize and evaluate the use of the microwave as a cooking method for shear force determination, against a standard protocol and establish the correlation to sensory tenderness.

The effect of carbon monoxide pretreatment exposure time on the colour stability and quality attributes of vacuum packaged beef steaks

The effect of 5% CO pretreatments prior to vacuum packaging of beef striploin steaks (Longissimus thoracis et lumborum, LTL) on quality attributes, primarily colour stability was investigated. The aim was to determine the optimum pretreatment that would induce the desirable red colour, while allowing discoloration to occur by the end of a 28-day display period (2°C), so as to not mask spoilage. A range of pretreatment exposure times (1, 3, 5, 7, 9, 15 and 24h) were applied to steaks using a gas mixture of 5% CO, 60% CO₂ and 35% N₂. The 5h CO pretreatment exposure time achieved the desirable colour and discoloration reached unacceptable levels (a*=12, C*=16) by the use-by date (28days), thus ensuring consumers' of a reliable visual indication of freshness and addressing concerns about safety. The 5% CO pretreatment had no negative effect on microbiological safety, lipid oxidation, cooking loss and WBSF measurements at the end of storage (P>0.05).