Warner-Bratzler Shear Force Measurements Research Articles

Relationship between sensory attributes and instrumental texture properties in meat analog patty system substituted with sweet potato stem.

Understanding the relationship between perceived sensory attributes and measurable instrumental properties is crucial for replicating the distinct textures of meat in plant-based meat analogs. In this study, plant-based patties composed of textured vegetable protein (TVP) and 10%, 20% and 30% TVPs were substituted with fibers from sweet potato stem (SPS), and their instrumental texture and sensory properties were evaluated. Samples with 20% SPS showed hardness, cohesiveness and chewiness, which are the mechanical indicators most similar to those of meat. A descriptive sensory analysis by ten trained participants indicated that the SPS-supplemented meat analog patties exhibited characteristics similar to pork patties in terms of firmness, toughness, cohesiveness and smoothness compared to the TVP-only sample. A strong positive correlation between instrumental hardness and sensory firmness was observed (P < 0.01); however, cohesiveness, springiness and chewiness did not show any correlation between instrumental and sensory analyses. Warner-Bratzler shear force (WBSF) values showed positive correlations with sensory cohesiveness, chewiness, toughness, fibrousness, moistness, firmness and springiness (P < 0.05). The results demonstrated the feasibility of physically treated fibers from SPS as a partial substitute for TVP in developing meat analogs. Additionally, this study suggested that instrumental hardness and WBSF measurements can be sound parameters for representing sensory texture characteristics while further developing plant-based meat analogs. © 2024 Society of Chemical Industry.

How does the inclusion of a companion forage alongside perennial ryegrass influence production performance, sensory perception and consumer liking of lamb meat?

In sheep production systems, diet type is an important factor affecting the eating quality of the meat produced. The objective of this study was to assess the effect of binary swards on the slaughter performance, descriptive sensory profile, consumer liking and instrumental texture of lamb meat. Five dietary treatments were investigated, perennial ryegrass (Lolium perenne L.; PRG), PRG plus white clover (Trifolium repens L.; PRG+WC), PRG plus red clover (Trifolium pratense L.; PRG+RC), PRG plus chicory (Chicorium intybus L.; PRG+Chic) and PRG plus plantain (Plantago lanceolata L.; PRG+Plan). Post – weaning sixty Texel sired crossbred lambs (n = 12 per dietary treatment) were selected from the main cohort of lambs born in 2022 and further balanced for sex and reared litter size. The M. longissimus thoracis et lumborum (LTL) was obtained from each lamb post-slaughter. Meat samples were analysed by a trained sensory panel, a consumer panel as well as Warner-Bratzler shear force (WBSF) measurements. All data were analysed using a linear mixed model PROC MIXED in SAS. Mean slaughter weights of 46.0 ± 0.36 kg and cold carcass weights of 22.2 ± 0.51 kg were achieved with no differences observed across dietary treatments (P > 0.05). On average, lambs were 217 d of age at slaughter. Lambs finished on PRG and PRG+Plan had similar growth rates, however binary mixtures containing PRG plus any one of WC, RC (P < 0.01) or Chic (P < 0.05) increased average daily gain (ADG) and reduced the number of days required for lambs to reach slaughter (P < 0.05), relative to lambs grazing the PRG monoculture. Meat from PRG+Plan lambs was scored lower by the trained sensory panel for initial tenderness (P < 0.001) and overall tenderness (P < 0.001) when compared to meat from any other dietary treatment. Consumers scored meat from PRG or PRG+WC lambs higher for tenderness (P < 0.05) and flavour (P < 0.01) in comparison to meat produced from PRG+Plan lambs. Relative to meat from PRG+Plan lambs, PRG, PRG+WC and PRG+Chic lamb meat scored higher for overall liking (P < 0.01) when assessed by the consumer panel. Results show that companion forage inclusion increased lamb growth performance in the post-weaning period thus reducing age at slaughter. However, findings suggest that the addition of plantain to the grazed sward may negatively affect the eating quality of lamb meat, highlighting the need to consider diet type in tandem with meat eating quality when selecting finishing systems for pasture fed lambs.

Effects of dietary oil inclusion on meat quality of immunocastrated male pigs

Diets high in fat have been used in the production of pigs in the growing and finishing stages for the improvement of meat production and quality parameters. Therefore, this study was conducted to evaluate the effect of adding different oil sources to the diet of immunocastrated male pigs on meat quality characteristics. Ninety-six pigs were randomly allotted to one of four dietary treatments, with six replicate pens per treatment and four pigs per pen. Dietary treatments consisted of diets supplemented with 1.5% soybean oil (SO; control) or 3% oil from SO, canola oil (CO), or fish oil (FO). After 98 days on trial, 18 pigs per treatment (n = 72) were slaughtered and samples of the Longissimus dorsi muscle were taken for Warner-Bratzler shear force and color (L*, a*, and b*) measurements. Loins from pigs fed diets containing either 3% SO or CO had decreased Warner-Bratzler shear force (P = 0.04) than those from pigs fed the control diet. Dietary treatments had no effect on color components of fresh loin. These results indicate that feeding 3% SO or CO increased pork tenderness, without compromising color meat of immunocastrated male pigs.

Alternative Merchandising Strategy of the Beef Top Round

ObjectivesThe study objectives were to compare the deep (D) vs. superficial (S) portions of the beef top round (NAMI #169A PSO1), semimembranosus (SM) muscle, for tenderness, lipid oxidation, and color.Materials and MethodsTo simulate the retail setting, USDA Choice top rounds (n = 12) were purchased from a commercial food distributer and delivered to the University of Idaho Meat Science Laboratory under refrigeration. Top rounds were aged for 21 to 24 d from their pack date prior to removing the SM for subsequent analysis. Four steaks were cut from each SM proximally to distally. To account for steak location, steaks were systematically assigned to one of the following analyses; Warner-Bratzler Shear Force (WBSF) measurement, lipid oxidation using the Thiobarbituric Acid Reactive Substances (TBARS) method, subjective and objective color analysis on the whole steak to calculate color uniformity (two-toning), and subjective and objective color of a steak separated into D and S portions. The separating cut was made approximately two inches from the superficial edge of the steak. After cutting, WBSF steaks were cooked on clamshell grills to an internal temperature of 71°C. Steaks were then chilled overnight before 6 cores were sheared perpendicular to the muscle fiber direction on a WBSF machine. Steaks were sampled and evaluated for TBARS on Days 0 and 4 of retail display, while color was evaluated subjectively and objectively on Days 0, 1, 2, 3, and 4 of retail display. Steaks used for TBARS and color analysis were placed on white Styrofoam trays, overwrapped with an oxygen permeable PVC film, and displayed in a glass-fronted retail display case at 3°C for 4 d to simulate retail display. Data were analyzed using the mixed models procedure of the Statistical Analysis System (SAS Institute, Inc., Cary, NC) and significance was determined at P &lt; 0.05.ResultsMean Warner-Bratzler shear force values were lower (P = 0.0012) in the S (4.2 kg) than the D (5.2 kg) portion of the SM. On Day 0, D and S portions had similar TBARS values (0.172 vs. 0.118 mg MDA/kg Meat); yet, by Day 4, the D portion had substantially greater TBARS values than the S portion (0.497 vs. 0.194 mg MDA/kg Meat; treatment × day of retail display interaction, P &lt; 0.0001). The D portion was lighter (higher L*; P &lt; 0.0001) colored than the S portion. Furthermore, the D portion became less red compared to the S portion during simulated retail display (treatment × day of retail display interaction; P &lt; 0.0001). The whole steak had greater levels of two-toning initially, as well as throughout the 4 d of retail display, compared to the D and S portions (treatment × day of retail display interaction; P &lt; 0.0001). Therefore, cutting top round steaks into a D and S portion would result in the steaks being more uniform in color. Additionally, the S portion has longer shelf-life as well as improved tenderness compared to the D portion.ConclusionIn conclusion, the S portion may be able to generate a premium compared to the whole steak at the retail level because of its superiority in color to the D portion and more uniform color compared to the whole steak.

An intelligent machine vision-based smartphone app for beef quality evaluation

Beef tenderness is the most important attribute correlated with beef quality, consumer satisfaction, and purchasing decisions. Nowadays, a rapid, non-invasive, and non-destructive evaluation and prediction of beef tenderness and quality from fresh product attributes is desired in industries, laboratories, and markets dealing with beef handling, processing, analyzing, and buy and sell. In this study, a new machine vision-based smartphone app was developed and verified for the first time in order to predict beef tenderness from fresh beef image captured under uncontrolled conditions. In order to eliminate the effects of uncontrolled imaging conditions, an illumination-, rotation-, scale-, and translation-invariant image processing algorithm was developed so that a common user can easily capture the image of the beef sample with more degree of freedom in terms of luminance, rotation, scale, and translation with no worries about the accuracy of the results. The obtained preprocessed image textural features were well correlated with instrumental data obtained using Warner-Bratzler shear force measurement through artificial neural network technique. The developed android app was installed on a LG G4 H815 smartphone and its performance was assessed using thirty unseen beef samples. The probability of occurrence of 2-D correlation coefficients obtained from the analyses of all the beef samples subjected to the image processing algorithm showed the average probability of 0.92, which strongly supported the robustness of the developed algorithm. The best obtained neural network model could predict the tenderness values with mean absolute percentage error (MAPE) of 3.28% and coefficient of determination (R2) of 0.97. The app promisingly predicted the beef tenderness values of the unseen samples with mean squared error (MSE) of 3.34, MAPE of 3.74%, and R2 of 0.99. Accordingly, the developed app can be a low-cost and user-friendly tool for predicting beef tenderness and quality from its real-world image.

Case Study: Effects of inclusion of wet brewers grains on the growth performance, carcass characteristics, and meat quality of finishing cattle

ABSTRACT Wet brewers grains (WBG) are an increasingly available by-product of the growing craft beer industry that may be useful in finishing cattle rations. Therefore, the objective of this pilot study was to determine the effects of including WBG sourced from craft brewing on the growth performance, carcass characteristics, and meat quality of finishing steers and heifers. Twenty-four [n = 24; 12 heifers (303 kg), 12 steers (346 kg)] crossbred calves were blocked by BW within sex to 12 pens (2 calves of the same sex per pen) in a 2 × 2 factorial arrangement with 3 replications per treatment and fed for 140 d. Model factors included calf sex and finishing diet [corn silage and whole shelled corn finishing diet (control) and control + 7.2% WBG]. Primal ribs (Institutional Meat Purchase Specification #103) were obtained and rib eye steaks (Institutional Meat Purchase Specification #1112) were fabricated from the 9th to 11th rib portion for additional analyses. No differences were observed in total gain, ADG, or G:F between diets (P > 0.05). However, there was a diet × sex interaction (P 0.05) in HCW, YG, or marbling score, but rib fat thickness was less (P = 0.020) in WBG calves than in control calves. Diet did not alter Warner-Bratzler shear force, package purge, or cook loss measurements (P > 0.05). These data indicate low-level inclusion of WBG can maintain performance and quality of finishing cattle similar to conventional finishing diets.

Use of liquid isoelectric focusing (OFFGEL) on the discovery of meat tenderness biomarkers

Protein biomarkers of meat tenderness are known to be of primary importance for the prediction of meat quality, and hence, industry profitability. Proteome analysis was performed on meat from 8 Main Anjou beef cattle, previously classified as tender or tough meats by Warner Bratzler shear force measurements. Myofibrillar fraction of Longissimus thoracis muscle was separated by a novel fractionation approach based on liquid isoelectric focusing (OFFGEL) and further analyzed by SDS-PAGE and liquid chromatography coupled to tandem mass spectrometry.Obtained OFFGEL fraction profiles were reproducible allowing the comparison of both meat qualities and revealing 7 protein bands capable to discriminate between tender and tough samples. The proteins present in these bands were troponin T, Heat Shock protein beta-1, creatine kinase, actin, troponin C, myosins 1 and 2 and myozenin-1. The latter protein has not been previously reported as a marker of meat tenderness. SignificanceThis study introduces an innovative proteomic approach for the study of muscle proteome. The fact of obtaining fractions in liquid state after OFFGEL fractionation allows for a faster analysis of proteins by mass spectrometry, being an interesting alternative to more classical proteomic approaches based on two dimensional gel electrophoresis (2-DE).

Influence of Cook Method and Degree of Doneness on Beef Flavor Attributes in Flap and Skirt Steaks

ObjectivesBeef flavor is very complex and the most important driver for consumer acceptance. Cooking method, Quality grade, and cooked internal temperature may affect beef flavor. In this study, 3 beef cuts (outside skirt, inside skirt, and flap), 2 Quality grades (USDA Choice and Select), 3 cooking methods (pan fry, pan grill, and outside grill), and 3 internal cook temperature endpoints (58°C, 70°C, and 80°C) were used to better understand trained descriptive beef flavor and texture attributes, and Warner-Bratzler shear force (WBSF) tenderness.Materials and MethodsMeat sources were purchased as subprimals in 6 reps for each cut and were fabricated into 10.16 cm wide steaks. The USDA upper two thirds Choice and USDA Select inside skirt, outside skirt, and flap steaks were cooked using a pan fry, pan grill, or outside grill methods. The steaks were cooked to an internal temperature of either 58.3, 70 or 80°C to represent medium rare, medium and well-done steaks. The steaks were evaluated by an expert trained meat descriptive panel for beef flavor and texture attributes. The trained panel descriptive flavor attributes, and WBSF were analyzed using Proc Means and Proc GLMMIX procedures of SAS (version 9.4, SAS Inst. Inc., Cary, NC) with a predetermined ɑ of 5%.ResultsCooking method and internal cook temperature endpoint tended to impact beef flavor to a greater extent than USDA Beef Quality grade for outside skirt, inside skirt and flap steaks. Internal cook temperature endpoint affected beef identity, brown, bloody/serumy, metallic, burnt, smokey-charcoal, and juiciness (P < 0.05). Pan frying tended to result in more off-flavor development and outside grilling was more often associated with positive flavor attributes. Choice steaks tended to have more positive beef flavor attributes such as beef identity, umami, brown and roasted. Quality grade affected fat-like, cardboardy, juiciness, muscle fiber tenderness and beef flavor (P < 0.05) for all 3 cuts. Pan grilling tended to result in intermediate flavor for steaks when compared to steaks cooked using outside grilling and pan frying cooking methods. The flavor attributes generally affected by cooking method included beef identity, brown, metallic, smokey-charcoal (P < 0.05).Treatments had an effect on flap tenderness measured by WBSF, Choice flap steaks were more tender (P < 0.05) than Select flaps and flap steaks cooked to 80°C were less tender (P < 0.05) than other internal temperatures. Pan-grilled flap steaks were more tender (P < 0.05) than steaks from the other cooking methods. For inside skirts, there was no effect (P > 0.05) for Quality grade on tenderness measured by Warner-Bratzler shear force values. However, inside skirts cooked to 58°C were more tender than other internal temperature endpoints, and pan-grilled skirts were more tender than other cooking methods (P < 0.05). Lastly, for WBSF measurements, treatments had no impact (P > 0.05) on outside skirt steaks.ConclusionIn the beef industry, beef flavor is a driver of consumer acceptability. This research was conducted to assist in the development of the Beef Flavor Myology tool that will aid in determining factors that impact beef flavors across various cuts, cooking methods, marbling levels, and cooked internal temperature.

A comparison between Warner-Bratzler shear force measurement and texture profile analysis of meat and meat products: a review

Texture is one of the most important characteristics of meat and we can explain it as the human physiological–psychological awareness of a number of rheological and other properties of foods and their relations. In this paper, we discuss instrumental measurement of texture by Warner-Bratzler shear force (WBSF) and texture profile analysis (TPA). The conditions for using the device are detailed in WBSF measurements, and the influence of different parameters on the execution of the method and final results are shown. After that, the main disadvantages are reflected in the non-standardized method. Also, we introduce basic texture parameters which connect and separate TPA and WBSF methods and mention contemporary methods with their main advantage.

Assessment of Postmortem Aging Effects on Texas-style Barbecue Beef Briskets

Palatability traits (tenderness, juiciness, flavor, and overall liking) of beef briskets (n = 48) were evaluated for 3 different postmortem aging period comparisons: 7 d vs. 21 d (Set 1), 21 d vs. 35 d (Set 2), and 7 d vs. 35 d (Set 3). Briskets were prepared as Texas-style barbecue by seasoning with salt and pepper and smoking with oak wood over a long period (approx. 11 h) using a commercial oven designed for such purposes until deemed tender (approx. 85°C internal temperature). Within each treatment set, Warner-Bratzler shear (WBS) force measurements did not differ (P &gt; 0.05) between aging days; however, WBS force measurements for point (Mm. pectorales superficiales composed of the M. pectoralis transversus and M. pectoralis descendens) were lower (P &lt; 0.05) compared to the flat portions (M. pectorals profundus) within each aging set. Consumer panelists did not (P &gt; 0.05) detect differences between aging days within each set for overall liking, flavor liking, tenderness liking, and juiciness liking. Conversely, differences were found between brisket point and flat portions; Set 1 differed for flavor liking (flat &gt; point; P = 0.0348) and juiciness liking (point &gt; flat; P = 0.0004), Set 2 differed for overall liking (flat &gt; point; P = 0.0499) and juiciness liking (point &gt; flat; P &lt; 0.0001), and Set 3 differed for overall liking (flat &gt; point; P = 0.0296) and juiciness liking (point &gt; flat; P = 0.0112). Our findings indicate postmortem aging did not improve beef brisket palatability, but we did note differences between point and flat portions. Preparing beef briskets as Texas-style barbecue resulted in products with low WBS values and high consumer palatability ratings, which helps demonstrate why barbecued briskets are so popular.

Assessment of Postmortem Aging Effects on Texas-style Barbecue Beef Briskets

Palatability traits (tenderness, juiciness, flavor, and overall liking) of beef briskets (n = 48) were evaluated for 3 different postmortem aging period comparisons: 7 d vs. 21 d (Set 1), 21 d vs. 35 d (Set 2), and 7 d vs. 35 d (Set 3). Briskets were prepared as Texas-style barbecue by seasoning with salt and pepper and smoking with oak wood over a long period (approx. 11 h) using a commercial oven designed for such purposes until deemed tender (approx. 85°C internal temperature). Within each treatment set, Warner-Bratzler shear (WBS) force measurements did not differ (P &gt; 0.05) between aging days; however, WBS force measurements for point (Mm. pectorales superficiales composed of the M. pectoralis transversus and M. pectoralis descendens) were lower (P &lt; 0.05) compared to the flat portions (M. pectorals profundus) within each aging set. Consumer panelists did not (P &gt; 0.05) detect differences between aging days within each set for overall liking, flavor liking, tenderness liking, and juiciness liking. Conversely, differences were found between brisket point and flat portions; Set 1 differed for flavor liking (flat &gt; point; P = 0.0348) and juiciness liking (point &gt; flat; P = 0.0004), Set 2 differed for overall liking (flat &gt; point; P = 0.0499) and juiciness liking (point &gt; flat; P &lt; 0.0001), and Set 3 differed for overall liking (flat &gt; point; P = 0.0296) and juiciness liking (point &gt; flat; P = 0.0112). Our findings indicate postmortem aging did not improve beef brisket palatability, but we did note differences between point and flat portions. Preparing beef briskets as Texas-style barbecue resulted in products with low WBS values and high consumer palatability ratings, which helps demonstrate why barbecued briskets are so popular.

Ionophore strategy affects growth performance and carcass characteristics in feedlot steers.

One hundred ninety-two steers (BW = 354 ± 23.5 kg) were used in a randomized block design to evaluate the effects of ionophore and ractopamine hydrochloride (RH) supplementation strategies on performance and carcass characteristics. Twelve pens of 4 steers were assigned to each of the following treatments: unsupplemented control (CON), laidlomycin propionate (12.1 mg/kg DM) with or without RH (LPRH and LP, respectively), and monensin sodium (36.4 mg/kg DM) with RH (MSRH). Steers were fed for 151 d, of which respective treatments received RH (Actogain; Zoetis, Florham Park, NJ) at a rate of 300 mg/(animal · d) for the final 32 d. Laidlomycin was removed from the LPRH treatment during this period, as no combination feeding has been approved. Upon harvest, carcass data were collected by trained personnel, and subsequent analysis of the LM was conducted to estimate tenderness using Warner-Bratzler shear force (WBSF). Prior to RH supplementation, both LP and LPRH had greater ADG ( ≤ 0.02) and G:F ( < 0.01) than CON, whereas MSRH was intermediate. During the final 32 d, MSRH improved G:F ( ≤ 0.02) compared to all other treatments and tended to increase ADG over unsupplemented controls ( = 0.05). Cattle receiving LP without RH had significantly greater BW at d 151 than CON ( = 0.02), whereas both RH treatments tended to improve final BW ( ≤ 0.09). Ionophores improved ADG ( ≤ 0.03) and G:F ( < 0.01) for the entire feeding period, and although LP-supplemented cattle had greater DMI for the final 32 d than both RH treatments ( ≤ 0.01), intakes for the 151-d trial were similar among treatments. Carcass weights were greater ( = 0.04) in cattle fed LP with no RH than CON, where cattle yielded an average of 12 kg more HCW. Ractopamine increased LM area in MSRH-supplemented cattle ( = 0.03) and tended to increase LM area for steers receiving LPRH ( = 0.07). Longissimus steaks of MSRH-supplemented cattle had greater WBSF values than CON ( = 0.04) after 7 d of postmortem aging and greater WBSF values than LPRH steaks after 28 d ( = 0.03). All other carcass and WBSF measurements were similar among treatments. The results of this study indicate that LP supplementation without RH may yield a performance similar to and carcass responses associated with the administration of a β-agonist. These results also suggest that performance and carcass characteristics for cattle fed LP are similar to those of cattle fed monensin throughout the feeding period.

Correlation of fresh muscle firmness with sensory characteristics of pork loins destined for a quality focused market.

Production of pork for quality-driven export markets offers economic incentive. Pork processors use subjective firmness as a sorting tool for loins intended for high-quality export. The objectives of this study were to determine 1) durometer efficacy in muscle, 2) if firmness on one portion of the loin is indicative of other locations, 3) if 1 d firmness is related to export quality traits, and 4) if variation in firmness is explained by mechanistic measures. Subjective firmness scores (1 = extremely soft and 5 = extremely firm) were determined by a trained individual 1 d (initial time point) postmortem. Loins (North American Meat Processors number 414 Canadian back; = 154) were wet aged for 28 d at 1.7°C. On d 28, a panel of 4 individuals assigned firmness scores on the ventral side of the loin at the area of the 10th rib, the anterior half, and the posterior half of the loin. Durometer readings were collected at the area of the 10th rib on the dorsal and ventral side of the loin. Spearman correlation coefficients were computed in SAS (version 9.3) to account for nonnormality of categorical data. Subjective firmness measurements at d 28 at the 10th rib and on the anterior portion of the loin were not correlated ( ≥ 0.21) with whole loin durometer readings on the dorsal or ventral portion of the loin or the average of the whole loin values. Subjective firmness (d 28) at the 10th rib accounted for 38.44 ( = 0.620) and 48.30% ( = 0.695) of the variation in firmness at the anterior portion of the loin and the posterior portion of the loin, respectively ( ≤ 0.05). One-day subjective firmness measurements were correlated with 28-d Warner-Bratzler shear force measurements ( = 0.174, = 0.03) but were not significantly correlated with sensory characteristics ( ≥ 0.08). Purge tended to be correlated with 1 d firmness ( = 0.136, = 0.10); however, drip and cooking loss, 24-h and 28-d pH, and soluble and insoluble collagen content were not correlated ( ≥ 0.34). Firmness measurements collected in the production facility (1 d) were negatively correlated with iodine value (IV; = -0.199, = 0.02), yet no 28-d subjective firmness measurements were correlated with IV ( ≥ 0.33). When loins not achieving export standards are removed from the population, 1 d firmness was not correlated to export quality or sensory characteristics (d 28). Differences in firmness were not explained by mechanistic measures. Inconsistencies among subjective and objective firmness measurements suggest that the durometer may not be an appropriate way to determine firmness.

A comparison of technical replicate (cuts) effect on lamb Warner–Bratzler shear force measurement precision

The Warner–Bratzler shear force (WBSF) of 335 lamb m. longissimus lumborum (LL) caudal and cranial ends was measured to examine and simulate the effect of replicate number (r: 1–8) on the precision of mean WBSF estimates and to compare LL caudal and cranial end WBSF means. All LL were sourced from two experimental flocks as part of the Information Nucleus slaughter programme (CRC for Sheep Industry Innovation) and analysed using a Lloyd Texture analyser with a Warner–Bratzler blade attachment. WBSF data were natural logarithm (ln) transformed before statistical analysis. Mean ln(WBSF) precision improved as r increased; however the practical implications support an r equal to 6, as precision improves only marginally with additional replicates. Increasing LL sample replication results in better ln(WBSF) precision compared with increasing r, provided that sample replicates are removed from the same LL end. Cranial end mean WBSF was 11.2±1.3% higher than the caudal end.

Rapid detection of frozen pork quality without thawing by Vis–NIR hyperspectral imaging technique

Quality determination of frozen food is a time-consuming and laborious work as it normally takes a long time to thaw the frozen samples before measurements can be carried out. In this research, a rapid and non-destructive determination technique for frozen pork quality was tested with a hyperspectral imaging (HSI) system. In this study, 120 pieces of pork meat were frozen by four kinds of methods with various freezing temperatures from −20 to −120°C. The hyperspectral images of the samples were acquired at the frozen state. Quality indicators including drip loss, pH value, color, cooking loss and Warner–Bratzler shear force (WBSF) of the samples were measured after thawing. The spectral characteristics of the frozen meat samples were studied and it was revealed that the reflectance at 1100nm had a close relationship with the freezing temperature (R=−0.832, p<0.01). Partial least squares regression (PLSR) was applied to establish the spectral models, and the models were then optimized. Results showed that the improved region of interest (ROI) method could be used to extract effective spectral information to withstand the interference of freezing, and choosing appropriate spectral bands and spectral pretreatment techniques were crucial to develop robust mathematical model. The performances of the models established were diverse based on different quality indicators. The coefficients of determination for prediction (Rp2) for L*, cooking loss, b*, drip loss and a* were 0.907, 0.845, 0.814, 0.762, and 0.716, respectively. However there were low correlations (Rp2) for pH and WBSF measurements. The current study indicated that HSI had the potential for non-destructive determination of frozen meat quality without thawing.

Analysis of the genetic effects of CAPN1 gene polymorphisms on chicken meat tenderness.

The micromolar calcium-activated neutral protease gene (CAPN1) is a physiological candidate gene for meat tenderness. Four previously identified single nucleotide polymorphism (SNP) markers located within the CAPN1 gene were evaluated for their associations with variation in the meat tenderness of a Chinese indigenous chicken breed, a higher meat quality breed (i.e., Qingyuan partridge chicken), and the commercial Recessive White chicken breed. Warner-Bratzler shear force measurements were used to determine tenderness phenotypes for all animals; intramuscular fat (IMF) content and rate of water loss in the breast muscles were also measured. Genotyping was performed by the polymerase chain reaction-ligase detection reaction method. Polymorphisms were identified for all markers, except CAPN1 2546. The frequency of allele T was zero, and allele C was fixed for CAPN1 2546 in the studied populations. The SNP CAPN1 3535 in the CAPN1 gene was significantly associated with tenderness and other meat quality traits, where animals inheriting the AA genotype had smaller shear force values, lower water loss rates, and higher IMF contents. Moreover, H1 (AAA) was the most advantageous haplotype for meat tenderness. The results of this study confirm some previously documented associations. Furthermore, novel associations have been identified that, following validation in other populations, could be incorporated into breeding programs to improve meat quality.

Association of pro-melanin concentrating hormone genotype with beef carcass quality and yield1

Beef cattle from 3 independent studies conducted in the Texas Panhandle (Exp. 1: n = 3,906 and Exp. 2: n = 4,000) and southern Idaho (Exp. 3; n = 542) were used to investigate the association of pro-melanin concentrating hormone (PMCH) genotype with beef carcass quality and yield attributes. Tissue samples were collected from each animal to determine which PMCH allele they expressed (Trial 1: AA, 62.60%; AT, 32.05%; and TT, 5.35%; Trial 2: AA, 64.33%; AT, 31.07%; and TT, 4.60%; Trial 3: AA, 65.87%; AT, 29.34%; and TT, 4.80%). Twenty-four hours after harvest, carcass attributes were evaluated for all carcasses and longissimus dorsi steak samples were allocated from a subset of carcasses in Exp. 2 (n = 352; AA, 49.43%; AT, 28.98%; and TT, 21.59%) and each carcass in Exp. 3. Warner-Bratzler shear force measurements were determined for each steak after aging for 7, 14, or 21 d postmortem. Carcasses from Exp. 1 and 2 expressing the AA genotype had greater (P < 0.01) 12th rib subcutaneous (s.c.) fat depth and marbling scores, concurrent with smaller (P < 0.01) LM area than carcasses of AT and TT genotypes. Subsequently, carcasses expressing the AA genotype were represented by a greater (P < 0.02) proportion achieving Prime and Premium Choice quality grades, and a lesser (P < 0.01) proportion grading Select or Standard. In all trials, carcasses of the AA genotype had greater (P < 0.04) calculated yield grades than carcasses of the TT genotype. Carcass composition was associated with PMCH genotype evident by calculated empty body fat differences (P < 0.04) between AA and TT cattle in Exp. 1 and 3, and differences (P < 0.01) among all 3 genotypes in Trial 2. Shear force data on 7-d postmortem aging tended (P = 0.06) to favor cattle of the AA genotype in Exp. 2. However, additional aging to 14 or 21 d minimized any tenderness differences. These data illustrate the potential relationship that may exist among PMCH genotypes and indicators of carcass composition.

Effectiveness of USDA instrument-based marbling measurements for categorizing beef carcasses according to differences in longissimus muscle sensory attributes1

This study quantified relationships between USDA instrument marbling measurements and LM sensory attributes (tenderness, flavor, juiciness), and shear force. Heifer (n = 390) and steer (n = 328) carcasses (all A-maturity) were selected at 4 beef processing plants in Colorado, Kansas, Nebraska, and Texas to represent 7 marbling degrees: traces (TR), slight (SL), small (SM), modest (MT), moderate (MD), slightly abundant (SA), and moderately abundant (MA). Classification into marbling groups was based on marbling scores determined using USDA-approved VBG 2000 grading systems. Strip loin steaks were obtained from both sides of each carcass and aged for 14 d. One steak was used to obtain Warner-Bratzler shear force (WBSF) and slice shear force (SSF) measurements. The other steak was evaluated by a trained sensory panel for juiciness, tenderness, intensity of flavors characterized as meaty/brothy, buttery/beef fat, bloody/serumy, livery/organy, and grassy; and overall sensory experience (negative or positive). Instrument marbling score explained 45%, 40%, 32%, 71%, and 61% of the observed variation in panel ratings for juiciness, tenderness, meaty/brothy flavor intensity, buttery/beef fat flavor intensity, and overall sensory experience, respectively. Increased degree of marbling resulted in steaks having greater (P < 0.001) juiciness (MA > SA > MD > MT > SM > SL = TR), meaty/brothy flavor (MA = SA > MD = MT > SM > SL > TR), and buttery/beef fat flavor (MA > SA > MD > MT > SM > SL > TR). Steak tenderness also increased (P < 0.001) as marbling degree increased; however, tenderness differences among marbling degrees differed for steers (MA = SA > MD = MT > SM > SL = TR) and heifers (MA = SA > MD > MT > SM > SL > TR). Steaks produced by steers had lower (P < 0.05) WBSF and SSF values, and were rated as more tender by sensory panelists than steaks produced by heifers, but the effect of sex on panel tenderness was significant only among steaks with TR marbling. Results of this study showed that instrument-based classification of beef carcasses, according to differences in marbling, effectively identified subsequent differences in strip loin steak sensory performance. Nearly all (98 to 99%) steaks with MA or SA marbling, and most (between 80% and 90%) steaks with MD and MT marbling, received positive ratings for overall sensory experience. In comparison, 62% of SM steaks, 29% of SL steaks, and 15% of TR steaks received positive sensory experience ratings.

Alterations in the Sarcoplasmic Protein Fraction of Beef Muscle with Postmortem Aging and Hydrodynamic Pressure Processing

Capillary electrophoresis (CE) and reversed-phase high performance liquid chromatography (RP-HPLC) analyses were utilized to detect differences in the sarcoplasmic protein fractions of beef strip loins subjected to aging and hydrodynamic pressure processing (HDP) treatments. At 48 h postmortem, strip loins (n = 12) were halved and subjected to control or HDP treatments. Following treatment, each half was divided into 3 portions which were aged for 0, 5, and 8 d. After each aging period, steaks were removed for Warner-Bratzler shear force (WBSF) analysis and for the extraction of sarcoplasmic proteins which were analyzed by CE and RP-HPLC. Aging by HDP interactions were not detected using either separation technique. With CE analysis, no HDP effects were observed; however, the relative peak area of 8 protein peaks ranging in size from 17 to >200 kDa were influenced by postmortem aging. Separation of proteins by RP-HPLC demonstrated that HDP influenced the relative size of 2 protein peaks while postmortem aging effects were observed in 6 peaks. Alterations in the sarcoplasmic protein fractions detected by both CE and RP-HPLC were correlated to WBSF measurements. Overall, data demonstrate that HDP has minimal effects on sarcoplasmic proteins and that aging related changes in the water soluble protein fractions of muscle may be useful as indirect indicators of beef tenderness. Using 2 different postmortem tenderization techniques, aging and hydrodynamic pressure processing, this study demonstrates that postmortem changes in the soluble protein fraction of beef may be useful as potential indicators of meat tenderness.

High-pressure-based hurdle strategy to extend the shelf-life of fresh chicken breast fillets

The combined effects of high hydrostatic pressure (HHP) and a commercial liquid antimicrobial edible coating consisting of lactic and acetic acid, sodium diacetate, pectin and water (“articoat-DLP”) followed by modified atmosphere packaging (MAP) on the shelf-life of chicken breast fillets were evaluated.All samples were held at 4 °C under MAP (30% CO2/70% N2) conditions and these were assigned to the following treatments: (i), control untreated fillets (C-MAP); (ii), fillets dipped in articoat-DLP (A-MAP); (iii) HHP (300 MPa) treated fillets followed by MAP (HP-MAP) and (iv) HHP (300 MPa) treated fillets after dipping in articoat-DLP (A-HP-MAP). During storage, packages were tested at intervals for CO2 and O2 concentrations, colour (CIE L* a* b*), pH, oxidative stability (TBARS), cooking loss, Warner–Bratzler shear force measurement and sensory analysis (colour, tenderness, juiciness, chicken aroma, oxidised flavour, off-flavours and overall acceptability). Total viable counts and numbers of Pseudomonas, lactic acid bacteria (LAB), Brochothrix thermosphacta, coliforms and Escherichia coli were also determined.The A-HP-MAP combination was the most efficient in extending the durability of chicken breast fillets, which maintained their sensory and microbiological quality for up to 28 days. At the time of rejection, total counts were 6.3 ± 0.7 log cfu/g, with LAB being dominant (100%). For A-MAP and HP-MAP fillets, the storage life was estimated to be two weeks while that of the untreated fillets (C-MAP) was estimated to be one week.Colour, tenderness and overall acceptability were the best maintained sensory attributes during storage for A-HP-MAP samples. The synergistic effect of this high-pressure-based hurdle strategy was higher than those previously reported when applying several combined hurdles to poultry meat.