Muscle Color Research Articles

Substitution of ramie (Boehmeria nivea) for alfalfa in improving the carcass and meat quality of Liuyang Black goats.

Ramie (Boehmeria nivea) is noted for the production of a large biomass that has a high protein content and is rich in antioxidants. It may thus serve as a high-quality forage material to replace alfalfa and improve the meat quality of farmed animals. In this study, we evaluated the carcass characteristics and meat quality of goats when 0, 35%, 75%, and 100% of dietary alfalfa was replaced with ramie. Crude protein content (linear, P < 0.0001) and key muscle color values at 24 h after slaughter decreased with increasing ramie levels. The content of most individual amino acids, non-essential amino acids (NEAA), total amino acids (TAA), branched chain amino acids (BCAA), functional amino acids (FAA), and flavor amino acids (DAA) decreased (P < 0.05) with increasing dietary ramie. The diet in which 35% of alfalfa was replaced with ramie yielded meat with the highest amino acid content, whereas the fatty acid profile was unaffected by the inclusion of ramie. These results indicate that ramie could be used as a potential dietary forage resource for goats, and that substituting 35% of alfalfa with ramie, which is equivalent to 126 g/kg DM content, would be optimal in terms of goat meat quality.

Finishing season and feeding resources influence the quality of products from extensive-system Gascon pigs. Part 1: Carcass traits and quality of fresh loin

Consumers perceive pork products from local breeds reared in extensive systems positively because of their specific quality properties and regional identity. The sensory, nutritional and technological qualities of these products depend, among other things, on pig production, especially its climatic conditions and the availability of feed resources, which can influence traits of muscle and fat tissue. The present study (part 1) was part of a larger project that assessed the influence of the finishing season and feeding resources on carcass and tissue traits and the quality of meat and dry-cured ham from Gascon pigs in an extensive system. Following the specifications of the Protected Designation of Origin “Noir de Bigorre”, castrated Gascon males were reared on rangelands (grassland and forest areas) and received a supplementary diet from 5 to 6 months of age until slaughter at a minimum of 12 months of age and ca. 170 kg live weight. Three finishing seasons were considered as follows: Winter (n = 18), Spring (n = 22) and Autumn (n = 23). To estimate specific effects of season on productive and quality traits and avoid bias due to effects of genes known to influence these traits, polymorphisms in the RYR1, PRKAG3, MC4R and LEPR genes were included in the analysis models. The finishing season did not influence growth rate. Compared to Winter pigs, Spring and Autumn pigs had slightly lower carcass fatness (P < 0.05), higher ultimate pH and redder and darker color of the Longissimus muscle (LM) (P < 0.01). Loin drip loss was low overall, but was higher for Spring pigs, whereas cooking loss and shear force were similar among seasons. Spring pigs tended to have the lowest LM lipid content, whereas LM myoglobin content remained unaffected. Autumn pigs had lower potential of lipid oxidation in LM than Winter and Spring pigs (P < 0.01), but muscle metabolic traits assessed via glycolytic and oxidative enzyme activities did not differ among seasons. The finishing season modified the backfat fatty acid (FA) profile, with a lower polyunsaturated FA percentage in Autumn pigs than Winter or Spring pigs (P < 0.001), even though the saturated and monounsaturated FA percentages did not differ. In particular, Spring pigs had the lowest n-6:n-3 and C18:2:C18:3 ratios (P < 0.001), as a result of grazing. Overall, Spring and Autumn finishing seasons seem more favorable to technological and sensory pork attributes, with an additional positive effect of Spring finishing on pork nutritional value.

The colour and sensory characteristics of longissimus muscle from beef cattle that grazed grass or consumed concentrates prior to slaughter.

Grazed grass is an important component of the majority of beef production systems used in temperate climates. Compared to concentrate-fed beef, 'grass-fed' beef can command a premium in some markets based on perceived differences in appearance and sensory characteristics. The influence of grazed grass per se, as well as the duration of grazing, on selected sensory characteristics of beef within a heifer production system was examined. In general, fat from grass-fed cattle was more yellow than fat from similar cattle fed concentrates, whereas muscle from grass-fed cattle was darker than muscle from cattle fed concentrates. At the same carcass weight, muscle from grass-fed cattle had a lower fat concentration than cattle fed concentrates. In the most extreme situation examined, whereby early-maturing heifers were fed concentrates ad libitum from weaning or grazed grass/conserved grass throughout life, until slaughtered at a similar carcass weight (260 kg) and differed in age by 5months, beef was rated similarly for tenderness and a range of flavours by a trained sensory panel. Within the range of beef heifer production systems examined, the sensory characteristics of grass-fed beef do not differ greatly from concentrate-fed beef. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The effects of simulated transport on the muscle characteristics of white-feathered end-of-cycle hens

Transportation of end-of-cycle hens (EOCH) may result in birds’ experiencing metabolic stress, which changes muscle characteristics. This study evaluated the impacts of simulated transport on muscle characteristics of white-feathered EOCH (65–70 wk). The factorial arrangement included treatments of T/RH (-10°C uncontrolled RH [-10], 21°C with 30 [21/30] or 80% RH [21/80], 30°C with 30 [30/30] or 80% RH [30/80]), duration (4, 8, 12 h), and feather cover (105 well-feathered [WF], 105 poorly-feathered [PF]). A total of 210 hens/replicate/farm (farm=block; 3 total) were tested during the simulated transport. Crates (one/duration/replicate), divided in half for each feather cover (seven hens/side), were placed in a climate-controlled chamber. Prior to exposure, hens were fasted (6 h). BW was taken pre- and post-exposure, and the difference was calculated as live shrink. Post-exposure to the test conditions, birds were slaughtered and carcasses were analyzed for muscle characteristics. Data were analyzed as a randomized complete block design (farm of origin as block) with ANOVA (Proc Mixed, SAS 9.4; significance declared at P ≤ 0.05). Duration resulted in more weight loss for the birds (P < 0.01). Final pH measures (30 h post-mortem) were higher in hens exposed to -10 than 21/80, 30/30, and 30/80 and this difference was exacerbated with time (breast P < 0.01 and thigh P = 0.01). For muscle color, breast and thigh (both feather covers; P = 0.01) were darker in the -10 treatment while redness values were higher in EOCH exposed to this treatment (breast and thigh P < 0.01). Additionally, thigh muscle redness was higher in PF hens (P < 0.01). Thaw and cooking losses were impacted by T/RH and duration (thaw loss P = 0.03 and cook loss P = 0.04). Cook loss was also influenced by T/RH and feather cover with PF hen muscles losing less water during cooking in the -10 treatment (P = 0.01). Overall, the largest impact from transport was found in hens exposed for a longer duration to -10 antemortem compared to other treatments, demonstrating a significant impact on muscle characteristics from ante-mortem stress.

Principal component analysis of lipid and protein oxidation products and their impact on color stability in bison longissimus lumborum and psoas major muscles

The study aims were to compare lipid (malondialdehyde [MDA], 4-hydroxy-2-nonenal [HNE]) and protein (carbonyl content [CAR]) oxidation products between two bison muscles (longissimus lumborum [LL] and psoas major [PM]) at different aging and retail display time and determine their influence on muscle color stability. Regardless of the aging and retail display time, LL showed greater redness (a* value; P = 0.04) and lower surface discoloration (P < 0.01) than PM as well as LL exhibited lower MDA, HNE, and CAR content compared to PM (P < 0.05). In both muscles, MDA showed the highest correlation to a* (r = −0.78; P < 0.01) and discoloration (rs = 0.82; P < 0.01) scores, particularly in PM muscle compared to LL muscle. In conclusion, the principal component analysis revealed 4 distinct color deterioration clusters within steaks displayed at d 4 according to the muscle and aging time, and MDA critically influences color deterioration patterns in bison muscles.

Bacteriophage cocktail supplementation improves growth performance, gut microbiome and production traits in broiler chickens

BackgroundEffective antibiotic alternatives are urgently needed in the poultry industry to control disease outbreaks. Phage therapy mainly utilizes lytic phages to kill their respective bacterial hosts and can be an attractive solution to combating the emergence of antibiotic resistance in livestock.MethodsFive hundred and four, one-day-old broilers (Ross 308) were allotted to 1 of 4 treatment groups in a completely randomized design. Treatments consisted of CON (basal diet), PC (CON + 0.025% Avilamax®), BP 0.05 (CON + 0.05% bacteriophage), and BP 0.10 (CON + 0.10% bacteriophage).ResultsA significant linear effect on body weight gain (BWG) was observed during days 1–7, days 22–35, and cumulatively in bacteriophage (BP) supplemented groups. The BWG tended to be higher (P = 0.08) and the feed intake (FI) was increased (P = 0.017) in the PC group over CON group. A greater (P = 0.016) BWG and trends in increased FI (P = 0.06) were observed in the experiment in birds fed PC than CON diet. At the genus level, the relative abundance of Lactobacillus was decreased in PC (65.28%), while it was similar in BP 0.05 and BP 0.10 (90.65%, 86.72%) compared to CON (90.19%). At the species level, the relative abundance of Lactobacillus salivarus was higher in BP 0.05 (40.15%) and BP 0.10 (38.58%) compared to the CON (20.04%) and PC (18.05%). A linear reduction in the weight of bursa of Fabricius (P = 0.022) and spleen (P = 0.052) was observed in birds fed graded level of BP and an increase (P = 0.059) in the weight of gizzard was observed in birds fed PC over BP diets. Linear and quadratic responses were observed in redness of breast muscle color in birds fed graded level of BP.ConclusionsThe inclusion of the 0.05% and 0.1% BP cocktail linearly improved broiler weight during the first 7 days, 22–35 days and cumulatively, whereas 0.05% BP addition was sufficient for supporting immune organs, bursa and spleen as well as enhancing gut microbiome, indicating the efficacy of 0.05% BP as a substitute antibiotic growth promoter in broiler diets.

Migratory state and patterns of steroid hormone regulation in the pectoralis muscle of a nomadic migrant, the pine siskin (Spinus pinus)

The endocrine system is known to mediate responses to environmental change and transitions between different life stages (e.g., a non-breeding to a breeding life stage). Previous works from the field of environmental endocrinology have primarily focused on changes in circulating hormones, but a comprehensive understanding of endocrine signaling pathways requires studying changes in additional endocrine components (e.g., receptor densities) in a diversity of contexts and life stages. Migratory birds, for instance, can exhibit dramatic changes in their physiology and behavior, and both sex steroids as well as glucocorticoids are proposed mediators of the transition into a migratory state. However, the role of changes in endocrine signaling components within integral target tissues, such as flight muscles, in modulating the transition into a migratory state remains poorly understood. Here, we examined changes in gene expression levels of and correlational patterns (i.e., integration) between 8 endocrine signaling components associated with either glucocorticoids or sex steroid signaling in the pectoralis muscles of a nomadic migratory bird, the pine siskin (Spinus pinus). The pectoralis muscle is essential to migratory flight and undergoes conspicuous changes in preparation for migration, including hypertrophy. We focus on endocrine receptors and enzymes (e.g., 5α-reductase) that modulate the signaling capacity of circulating hormones within target tissues and may influence either catabolic or anabolic functioning within the pectoralis. Endocrine signaling components were compared between captive birds sampled prior to the expression of vernal migratory preparation and during the expression of a vernal migratory state. While birds exhibited differences in the size and color of the flight muscle and behavioral shifts indicative of a migratory state (i.e., zugunruhe), none of the measured endocrine components differed before and after the transition into the migratory state. Patterns of integration amongst all genes did, however, differ between the two life stages, suggesting the contrasting demands of different life stages may shape entire endocrine signaling networks within target tissues rather than individual components. Our work aligns with previous endocrine studies on pine siskins and, viewed together, suggest additional studies are needed to understand the endocrine system’s role in mediating the development and progression of the vernal migratory state in this species. Further, the patterns observed in pine siskins, a nomadic migrant, differ from previous studies on obligate migrants and suggest that different mechanisms or interactions between endocrine signaling components may mediate the migratory transition in nomadic migrants.

Evaluation of the variability of instruments used in meat color assessments

The study objectives were to determine how different instrumental settings and measurement environments affect the means and variability of instrumental muscle color in pork loins and Boston butts (serratus ventralis). Three studies were conducted testing different variables; study 1 tested aperture type (closed vs. open), study 2 tested illuminant (D65 vs. C), and study 3 tested measurement environment (commercial facility vs. university; loins only). Within each set of loins and Boston butts, the 100 greatest and lowest lightness (L*), redness (a*), and yellowness (b*) measurements were determined for each machine/setting combination. Color data within a set were analyzed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC). Variances and coefficient of variation were calculated using the MEANS procedure. Coefficients of determination between machines within a set were calculated using the REG procedure. L* and a* measurements in loins and Boston butts were more variable when using an open aperture than a closed aperture (P ≤ 0.02). Illuminant did not affect L* or a* variability in either muscle (P ≥ 0.16). In loins and Boston butts, measurements from machine 1 explained 11% – 54% (P < 0.0001) of variation in machine 2 measurements when settings differed, and there was 17%–65% agreement between machines for extreme values. In loins, machine 1 measurements explained 41%–49% (P < 0.0001) of variation in machine 2 measurements under commercial conditions and 86%–92% (P < 0.0001) under controlled conditions. With identical settings, there was 49%–73% agreement between machines for the greatest and lowest 100 values under commercial conditions and 84%–90% agreement under university conditions. Overall, using a closed aperture decreased overall color variability compared with using an open aperture. However, it is difficult to compare studies measuring instrumental color when operational settings differ or the environment is not well controlled.

Characteristics of carcass and physicochemical traits of meat from male and female ducks fed a diet based on extruded soybean

Duck’ meat is characterized by good nutritional properties and gaining popularity in the consumer market. Extruded soybean is potentially more digestible than commonly use soybean meal (SBM), and is expected to influence carcass traits and the quality of breast and leg muscles. The study’ aim was to compare meat quality from both sexes’ ducks fed a diet with extruded soybean (ESB) as a substitute for SBM. Cherry Valley ducks were divided into two groups. The control group (1) was fed an SBM-based diet, and the treatment group (2) with ESB. Each group was divided into sex subgroups with 50 birds in each (5 replicates, 10 ducks each). Dissection and analysis of meats’ pH, colour, water-holding capacity (WHC), drip loss and chemical composition of breast and leg muscles were done. Interaction of Diet and Sex was calculated. In group 2 higher carcass weight, dressing percentage, weight of wings, leg muscles, total muscles, and better WHC were found. Dressing percentage, the proportion of neck with skin, breasts’ and stomach’ weight, and the weight and proportion of fat, and pH45min were higher in females (P < 0.05). The interaction was found for the pre-slaughter body weight, the weight of carcass remains, WHC in breasts (P < 0.05). The ESB feed had no negative effect on the analyzed traits and can be used in the ducks’ diet. Improved the WHC indicates the high suitability of meat for processing. A positive effect of diet on the muscles’ proportion and dressing percentage was noticed, which is important for consumers’ market. The sex-related differences and interactions between variables suggest separate rearing due to sex.

Effects of red macroalgae Asparagopsis taxiformis supplementation on the shelf life of fresh whole muscle beef.

This study was conducted to evaluate the effect of red macroalgae Asparagopsis taxiformis supplementation for cattle on the shelf life of fresh beef steaks (longissimus dorsi). Three treatment groups (seven steers per treatment) included: 1) Control diet, 2) Control diet + 0.25% of macroalgae inclusion (low dose, LD), and 3) Control + 0.5% of macroalgae inclusion (high dose, HD). After the animals were harvested, the strip loins from all animals were collected and aged for 14 days at the meat lab of the University of California, Davis. Then the strip loins were cut into steaks, packaged, and placed on a retail display case for 6 days. During a retail display, instrumental color (L*, a*, and b*) of lean muscle and external fat surfaces were measured every 12 h. Bacterial counts for total aerobic mesophilic bacteria (AMB), aerobic psychrotrophic bacteria (APB), and lactic acid bacteria (LAB) were assessed on days 0, 3, and 6 of retail display. The thiobarbituric acid reactive substances (TBARS) analysis was conducted to measure the lipid oxidation and the pH was also assessed on days 0, 3, and 6. No interactive effect between treatments and time on the shelf life of steaks was observed. The HD red macroalgae supplement decreased (P < 0.05) the lightness (L*) of the surface muscle of the steaks, while the lightness of the external fat was not affected (P < 0.05) by treatments throughout the retail display. The external fat yellowness of the steaks was lower (P < 0.05) in LD and HD treatment groups compared with the control group. An increase (P < 0.05) in counts of AMB, APB, and LAB was observed on the steaks from the steers in the HD treatment group while steaks in Control and LD group had similar bacterial numbers throughout the retail display. The results indicated that the shelf life of steaks from cattle in LD group remained the same as that of the Control group, but the HD of A. taxiformis caused a darker color of steaks with higher microbial counts, which may lead to a shortened shelf life due to undesirable appearance and faster microbial spoilage.

Effects of Dietary Inclusion of Canthaxanthin- and α-Tocopherol-Loaded Liposomes on Growth and Muscle Pigmentation of Rainbow Trout (Oncorhynchus mykiss)

Dietary inclusion of canthaxanthin, a common carotenoid pigment, has been long practiced in aquaculture to give the favorable flesh color in farmed salmonids. However, carotenoids are associated with limited solubility and poor physicochemical stability, and their dose in fish feed is widely regulated. In this study, we included canthaxanthin- and α-tocopherol-loaded liposomes into fish diets and evaluated the effects of supplemented fish feed on fish growth, color, nutrition, and canthaxanthin deposition in fillets of cultured rainbow trout (Oncorhynchus mykiss). The liposomes were fabricated using lecithin as phospholipids with the initial concentrations (IC = mcanthaxanthin/mlipids, % wt/wt) of canthaxanthin at 0.1%, 0.5%, and 1.0%. Particle size characterization showed that liposome mean sizes were 109.70 ± 6.36, 105.10 ± 8.41, and 109.20 ± 5.66 nm (mean ± SD; n = 3), respectively, corresponding with liposomes synthesized at canthaxanthin IC = 0.1%, IC = 0.5%, and IC = 1%. The polydispersity index (PDI) of all samples remained lower than 0.2. There were no significant differences in the mean size and PDI between blank lecithin liposome and canthaxanthin- and α-tocopherol-loaded liposomes. The encapsulation efficiency of canthaxanthin- and α-tocopherol-loaded liposomes decreased when increasing the concentration of canthaxanthin in lecithin liposomes, with EE% values of IC = 0.1%, IC = 0.5%, and IC = 1% being 85.3 ± 2.1, 72.9 ± 1.8, and 55.3 ± 2.6, respectively. For fish growth, at the end of the experiment, final weight was significantly higher in fish fed with diet supplemented with 1 g/kg canthaxanthin- and α-tocopherol-loaded liposomes (IC = 0.5%) in comparison to other experimental control groups. The difference in color of the salmon muscle was most apparent after two months of feeding. However, after three months, there was no noticeable change in the color score of the fish muscle, indicating saturation of color of the fish muscle. The above results suggest the potential of canthaxanthin- and a-tocopherol-loaded liposomes as the red pigment in fish aquaculture.

Ultrasound-assisted thawing accelerates the thawing of common carp (Cyprinus carpio) and improves its muscle quality

The effects of different power (0, 100, 300, and 500 W) ultrasonic-assisted immersion thawing (UT) on the thawing time and muscle quality (thawing/cooking loss, shear force, colour, water distribution and microstructure) of common carp (Cyprinus carpio) were investigated. The results showed that the thawing time decreased gradually with the increase of ultrasonic power, and the thawing time of ultrasonic thawing at 500 W (UT-500) was the shortest among all the thawing methods (P < 0.05). However, the thawing and cooking losses of UT-500 samples were the largest among all thawed samples, while those of UT-300 samples were the smallest (P < 0.05). In addition, the result of fish colour indicated that UT-300 was beneficial for maintaining the colour of fish muscle after thawing. Low field nuclear magnetic resonance analysis showed that UT-300 effectively reduced the fluidity and loss of immobilised and free water. Microstructure analysis showed that the microstructure of UT-300 sample was more complete than that of other thawing treatment samples. Therefore, appropriate ultrasonic power (300 W) during thawing could accelerate the thawing process of frozen common carp, and maintain its muscle quality.

Effects of Precooling with Slurry Ice on the Freshness of Farmed Perch (Lateolabrax japonicus) during Logistics Process

ABSTRACT The effects of precooling with slurry ice on quality changes of fresh farmed perch (Lateolabrax japonicus) during circulation were investigated. The basic component (ash, moisture, crude fat, and protein content), microbial (total viable counts, TVC), physicochemical (total volatile basic nitrogen, TVB-N), water-holding capacity (WHC), color difference indexes, and sensory evaluation were analyzed periodically. Scanning electron microscope (SEM) and low field nuclear magnetic resonance (LF-NMR) were measured in the experiments. The results showed that it took only 25 min for fresh perch to be chilled to 0°C with slurry ice (SI), which was one half of the time for samples treated with crushed ice. For the quality analysis, TVC and TVB-N in farmed perch muscle treated with SI were lower, and samples precooled with SI kept the color and sensory quality of fish muscle from day 4 better than that of crushed ice (P < .05). Meanwhile, the WHC and bound water content (T22 ) in muscle of slurry-iced samples were higher than that of crushed-iced samples. The results of SEM also confirmed that precooling with SI could keep the structural stability of muscle tissue. Therefore, SI is an efficient method for precooling and could be worthy of further study in short-distance transportation.

Antemortem inhibition of phosphoinositide 3-kinase causes changes in meat quality traits in broiler chickens

Phosphoinositide 3-kinase (PI3K) is an enzyme that mediates endocrinological responses, such as intracellular signaling of insulin and growth factors, and plays important roles in muscle homeostasis and growth. In this study, the effect of antemortem PI3K activity on meat quality traits was investigated using broiler chickens whose PI3K was inhibited pharmacologically. Breast and thigh muscles were harvested from broilers treated with the PI3K inhibitor wortmannin, and meat quality traits were evaluated by determination of color, water-holding capacity, and breaking strength. The pH and concentrations of glycogen and free amino acids were also investigated as determinants of the chemical properties of meat. The results indicated that antemortem PI3K inhibition by wortmannin modified breast muscle color with lower L∗ values (P < 0.05) and b∗ values (P < 0.05) and higher a∗ values (P < 0.05). Antemortem PI3K inhibition also increased the water-holding capacity of breast muscles (P < 0.05), although breaking strength was not much affected. In addition, antemortem PI3K inhibition increased the concentrations of free amino acids in breast muscles, especially arginine (P < 0.05) and glutamic acid (P < 0.05). Similar effects were observed in thigh muscles. Lower glycogen levels at sacrifice (P < 0.05) and the resultant higher pH during the postmortem period (P < 0.05) were associated with PI3K inhibition–induced changes in meat quality traits. The wortmannin-treated muscles shared certain features with dark, firm, and dry meat which is a common abnormal meat. These findings suggest that antemortem PI3K activity contributes to meat quality traits and is involved in the molecular mechanism of the production of meat quality abnormalities.

The influence of propolis and bee pollen on chicken meat quality

Across the world, as well as in Croatia, there is a continuous increase in the consumption of chicken meat, and attempts are being made in modern poultry production to improve its quality as much as possible by using various natural additives. The aim of this study was to determine the influence of dietary supplementation with propolis and bee pollen on the quality of chicken meat. In order to determine this effect, the carcass body weight of slaughtered chickens and carcass yield were determined, as well as the average pH1 and pH2 of chicken breast muscle, drip loss values, and skin color and chicken breast muscle color expressed as values of L* (lightness), a* (redness), and b* (yellowness). The study was conducted on 200 Ross 308 chickens, divided into five groups. Throughout the study, the control group of chickens was fed with a basal diet, while the experimental groups of chickens were fed with the basal diet supplemented with propolis and bee pollen, each supplement given separately or in combination in specific proportions. At the end of the experiment (42nd day), 10 chickens from each group were slaughtered for the analyses mentioned above. The carcass yield values were significantly higher (P = 0.038) and the drip loss values were significantly lower (P = 0.003) in the experimental groups in comparison to the control group. In addition, there was a statistically significant difference in b* skin color (P = 0.017) and b* chicken breast muscle color (P&lt;0.001) between the groups of chickens. The study showed that dietary supplementation with propolis and bee pollen has a significant positive effect on the quality of chicken meat.

Effects of maternal vitamin D3 status on quality traits of longissimus dorsi muscle in offspring pigs during postmortem storage

Maternal nutritional status has long lasting consequences on meat quality in offspring. We sought to determine how maternal vitamin D3 would influence quality traits of longissimus dorsi muscle in offspring pigs during postmortem storage. A total of 72 offspring pigs (150 d, Duroc × Landrace × Yorkshire) obtained from 3 sow feeding groups (9 sows per group) which contained 200 (low vitamin D3, LD), 800 (normal vitamin D3, ND) and 3200 (high vitamin D3, HD) IU of vitamin D3/kg basal diet during pregnancy to investigate the effects of maternal vitamin D3 status during pregnancy on meat quality attributes such as pH, shear force, water holding capacity (WHC), color, and low-field nuclear magnetic resonance (LF-NMR) T2 relaxation times of longissimus dorsi muscles in meat samples of offspring pigs during postmortem storage. The results showed that during postmortem storage times, HD group had higher pH value and WHC, while lower T21 relaxation time compared with LD group (P < 0.05), shear force of ND group was higher than that of HD group, while lower than that of LD group (P < 0.05), ND and HD groups had lower L*, b* values, T22 relaxation time, and higher a* value compared with LD group (P < 0.05). Meanwhile, postmortem storage decreased pH value of ND group, WHC of LD group, and L*, a* values of LD and ND groups, but increased b* values of LD and ND groups, and T22 relaxation time of all groups were insignificant (P < 0.05). These results indicated that maternal vitamin D3 status affected pH value, WHC, shear force, meat color and LF-NMR T2 relaxation time of longissimus dorsi muscles, which improved meat quality attribute and eating quality in offspring pigs through regulating meat quality index during postmortem storage.

147 Tenderness and Retail Display Evaluation of Non-Enhanced, Enhanced and High-Quality Pork Chops

Abstract Quality variation within the pork industry is commonly associated with intramuscular fat and muscle color. The objective of this study was to determine the effects of packaging, pork quality types, and cooking temperature on color and shear force. Normal, non-enhanced (N, n = 10), Enhanced with salt and phosphate (E, n = 10) and Highly Marbled (H, n = 10) pork loins from a local food distributor. Loins were cut into 2.54-cm-thick chops and assigned to retail display or tenderness evaluation. Retail display chops were assigned to 1 of 3 packaging treatments: polyvinyl chloride overwrap (PVC), carbon monoxide modified atmosphere packaging (CO-MAP) and high-oxygen modified atmospheric packaging (HiOx-MAP). Visual color measurement for muscle color (MC), fat color (FC), surface discoloration (SD), and surface color uniformity (SCU) was recorded on d 0, 2, and 4 of retail display. Pork tenderness was evaluated at 3 different degrees of doneness (63, 68, &amp; 74°C) using Warner-Bratzler shear (WBS) force. There were significant treatment and packaging interactions for muscle color. For muscle color score, E pork loins had a significantly lower (P &amp;lt; 0.05) muscle color score compared with N and H loins indicative of a brighter, more pale pink color. In addition, CO- and HiOx-MAP packaged chops were significantly brighter (P &amp;lt; 0.05) compared to PVC chops. There were treatment and degree of doneness main effects (P &amp;lt; 0.05) for WBS force values. Enhanced pork loins were more tender (P &amp;lt; 0.05) than N pork loins. Furthermore, pork chops cooked to 63 °C were more tender than chops cooked to 68 and 73°C. In conclusion, enhanced chops packaged in CO- or HiOx-MAP result in a brighter color of lean compared non-enhanced and high-quality. Additionally, the results suggest that enhanced, non-enhanced, and high-quality pork products available in market have different quality parameters.

Effects of Enhancement and Modified Atmosphere Packaging on Flavor and Tenderness of Dark-Cutting Beef

The objective of this study was to evaluate the effects of rosemary/beef flavor enhancement and modified atmosphere packaging (MAP) on retail display color and palatability of beef longissimus lumborum muscle. Dark-cutting beef strip loins (n = 8; pH &amp;gt; 6.0) and USDA Low Choice beef strip loins (n = 5) were selected from a commercial packing plant within 72 h of harvest. Dark-cutting strip loins were divided into 2 equal sections and randomly assigned to either nonenhanced or rosemary/beef flavor–enhanced treatments. Dark-cutting enhanced loins were injected to 110% of their green weight with a rosemary/beef flavor enhancement to attain 0.1% rosemary, 0.5% salt, and 0.55% beef flavor in the final product. Six 2.54-cm-thick steaks were cut from nonenhanced USDA Choice, nonenhanced dark-cutting, and enhanced dark-cutting strip loins and randomly assigned to one of 3 packaging treatments: vacuum packaging, carbon monoxide MAP (0.4% CO, 69.6% N, and 30% CO2), and high-oxygen MAP (80% O2 and 20% CO2). Following 3-d retail display, instrumental color measurements were recorded, and one steak from each packaging type was evaluated by a trained sensory taste panel and another used to measure Warner-Bratzler shear force. Enhanced dark-cutting steaks packaged in high-oxygen MAP and carbon monoxide MAP had greater a* values (P &amp;lt; 0.0001) than dark-cutting steaks in vacuum packaging. Enhanced dark-cutting steaks were lighter (P &amp;lt; 0.0001, greater L* values) than nonenhanced dark-cutting steaks. Nonenhanced dark-cutting steaks exhibited a lower (P = 0.03) overall juiciness compared to enhanced dark-cutting steaks. Enhanced and nonenhanced dark-cutting steaks were more tender (P = 0.002) than the USDA Choice steaks. Enhanced dark-cutting steaks had higher (P = 0.006) sour flavor in vacuum packaging than other packaging types. The results suggest that rosemary/beef flavor enhancement has the potential to improve the surface color of dark-cutting beef while improving or maintaining palatability.

Effect of fermented corn-soybean meal on carcass and meat quality of grower-finisher pigs.

The fermented feed has been identified as a potential alternative to antibiotics in feeds that markedly affects gut health and growth performance of pigs. Two recent studies performed in our laboratory investigated that the fermented corn-soybean meal (fermented feed, FF) improved the gut health of pigs. This study was conducted to determine the effect of a FF on the carcass, meat quality, muscle fatty acids profile, muscle amino acid and antioxidant ability of grower-finisher pigs. In this study, a total of 48 crossbred barrows (Duroc×Landrace×Large White) were randomly divided into 2 treatments with unfermented corn-soybean diet (Ctrl) and FF diet. Compared with control pigs fed a standard diet, the results showed that FF significantly increased the muscle colour of redness and significantly reduced muscle moisture loss rate. Furthermore, FF significantly increased the content of aromatic amino acids such as aspartic acid, glutamic acid and alanine. More importantly, FF increased monounsaturated fatty acid and polyunsaturated fatty acid content. Collectively, FF could be a promising feed strategy in improving meat quality and nutritional value in grower-finisher pig.

Low Dietary n-6/n-3 PUFA Ratio Regulates Meat Quality, Reduces Triglyceride Content, and Improves Fatty Acid Composition of Meat in Heigai Pigs.

Simple SummaryThe content of n-3 and n-6 polyunsaturated fatty acids (PUFA) in pork is linked to human health. Dietary fatty acid composition especially the n-6/n-3 PUFA ratio can affect meat quality in lean breeds of pigs. However, the effects of different dietary fatty acid composition on Chinese indigenous pig breeds are still poorly understood. In the current study, Heigai pigs were fed with different n-3/n-6 PUFA ratios diets (8:1, 5:1, and 3:1) to investigate the effects of dietary supplementation with different n-6/n-3 PUFA ratios on growth performance, meat quality, and fatty acid profiles. Low dietary n-6/n-3 PUFA ratio regulated pH and meat color of longissimus dorsi muscle (LDM), reduced triglyceride and total cholesterol contents, and enhanced the deposition of n-3 PUFA of LDM and subcutaneous adipose tissue (SAT). This study can provide an experimental reference for producing functional pork (e.g., better fatty acid composition) with the advantages of Chinese local breed pigs.The objective of this study was to investigate the effects of dietary supplementation with different n-6/n-3 polyunsaturated fatty acid (PUFA) ratios on growth performance, meat quality, and fatty acid profile in Heigai pigs. A total of 54 Heigai finishing pigs (body weight: 71.59 ± 2.16 kg) were randomly divided into three treatments with six replications (three pigs per replication) and fed diets containing different n-6/n-3 PUFA ratios: 8:1, 5:1, and 3:1. Pigs fed the dietary n-6/n-3 PUFA ratio of 8:1 had the highest feed to gain ratio (p < 0.01), carcass weight (p < 0.05), redness a* (p < 0.01), and yellowness b* (p < 0.01). Fatty acid compositions in longissimus dorsi muscle (LDM) and subcutaneous adipose tissue (SAT) were significantly changed (p < 0.01). Notably, the meat from the pigs fed with the low dietary n-6/n-3 PUFA ratio had higher n-3 PUFA contents (p < 0.01) and lower n-6/n-3 PUFA ratio (p < 0.01). The triglyceride and total cholesterol contents were significantly decreased in SAT from the pigs fed with dietary n-6/n-3 PUFA ratios of 5:1 (p < 0.05) and 3:1 (p < 0.01). Reducing n-6/n-3 PUFA ratio upregulated the expression of HSL (p < 0.05), CPT1 (p < 0.01), and FABP4 (p < 0.01) but downregulated ATGL (p < 0.01) expression. These results demonstrate that the lower n-6/n-3 PUFA ratio regulates meat quality and enhances the deposition of n-3 PUFA in Heigai pigs.