Rapid method for determining water-holding capacity in meat using video image analysis and simple formulae

Measuring water holding capacity in poultry meat

In the current scientific literature, one can find >100 different methods to evaluate water-holding capacity in fresh and cooked meat. The main concepts are based on removing some of the water by either gravity, application of pressure (e.g., centrifugal force), and heating while measuring water exudate to predict the water holding capacity (WHC) during storage, processing, cooking, and/or distribution. More sophisticated methods include nuclear magnetic resonance (NMR) in which the relaxation of water molecules within a meat protein/gel system is measured to predict how the water (75% in lean meat) will behave during processing. Overall, the number of tests reported is also so high because there are quite big variations in test conditions (e.g., 750-30,000 g for centrifugal testing). The aim of this article (outcome of a symposium on methods for poultry meat characterization) is to help the reader navigate through the different setups and suggest standardized testing based on scientific principles. The recommended WHC test is the application of low centrifugal force (750 g so sample is not permanently deformed) to a protein gel, while the sample is placed on a screen platform to avoid reabsorbing the liquid separating during the slowing down of the centrifuge. It is also recognized that some meat samples (e.g., high in fat) might require a different g-force, so it is recommended to employ both the conditions mentioned above and the lab-specific conditions. Our overall goal should always be to increase uniformity in test procedures, which will enhance our capabilities to compare results among research groups.

A comparison of Echium, fish, palm, soya, and linseed oil supplementation on pork quality

OBJECTIVE

Long chain n-3 polyunsaturated fatty acids (PUFA) exert positive effects on human health. The long chain n-3 PUFA of pork can be increased by adding fish oil to the diet. Due to the cost and availability of fish oil an alternative source must be found.

METHODS

This study evaluated the effect of five dietary oils on meat quality, fatty acid composition and lipid stability. The five diets contained 1% palm oil (Control), 1% soya oil, 1% linseed oil, 1% fish oil, and 1% Echium oil, respectively. The trial consisted of 60 gilts, randomly allocated to five groups.

RESULTS

All color parameters, extractable fat content, fat free dry matter, and moisture content of the m. longissimus muscle were unaffected by dietary treatment. Consumers and a trained sensory panel could not detect a difference between the control samples and the Echium oil sample during sensory analysis. Samples containing higher levels of PUFA (soya, linseed, fish, and Echium oil) had higher levels of primary and secondary lipid oxidation products after refrigerated and frozen storage. However, these values were still well below the threshold value where off flavors can be detected. The Echium oil treatment had significantly higher levels of long chain PUFA than the linseed oil treatment, but it was still significantly lower than that of the fish oil treatment.

CONCLUSION

Echium oil supplementation did not increase the levels of n-3 to the same extent as fish oil did. The result did however suggest that Echium oil can be used in pig diets to improve muscle long chain n-3 fatty acid content without any adverse effects on meat quality when compared to linseed, soya, and palm oil.

Measuring water holding capacity in pork meat images using deep learning

Water holding capacity (WHC) plays an important role when obtaining a high-quality pork meat. This attribute is usually estimated by pressing the meat and measuring the amount of water expelled by the sample and absorbed by a filter paper. In this work, we used the Deep Learning (DL) architecture named U-Net to estimate water holding capacity (WHC) from filter paper images of pork samples obtained using the press method. We evaluated the ability of the U-Net to segment the different regions of the WHC images and, since the images are much larger than the traditional input size of the U-Net, we also evaluated its performance when we change the input size. Results show that U-Net can be used to segment the external and internal areas of the WHC images with great precision, even though the difference in the appearance of these areas is subtle.

Direct Rub Inoculation of Fungal Flora Changes Fatty Acid Composition and Volatile Flavors in Dry-Aged Beef: A Preliminary Study

Here, we established a method to produce dry-aged beef (DAB) by rub inoculation with fungal flora on the prepared DAB surface. Portions of Holstein steers’ rumps were prepared by direct rub inoculation of fungal flora or without treatment (conventional DAB) and dry-aged for 26 days in an aging room at 2.9 °C and 90% relative humidity. We compared the fungal covering and meat quality, including fatty acid composition and volatile aromatic compounds, of fungal-inoculated DAB with those of the conventional DAB. The fungal-inoculated DAB was almost entirely covered with white mold, in contrast to the conventional DAB. Moreover, the proportion of oleic acid and the concentration of nine volatile compounds significantly increased in the raw meat of fungal-inoculated DAB compared with those in the conventional DAB (p < 0.05). These results suggested that direct rub inoculation of fungal flora from prepared DAB may accelerate DAB production and efficiently enhance the “melt-in-the-mouth” feeling and flavors of DAB.

Differences in Meat Quality of Six Muscles Obtained from Southern African Large-Frame Indigenous Veld Goat and Boer Goat Wethers and Bucks

Various meat quality characteristics of six muscles (Longissimus thoracis et lumborum (LTL), Semimembranosus (SM), Biceps femoris (BF), Supraspinatus (SS), Infraspinatus (IS), Semitendinosus (ST)) from large-frame Boer Goats (BG) and Indigenous Veld Goats (IVG: Cape Speckled and the Cape Lob Ear) were studied. Weaner male BG (n = 18; 10 bucks and 8 wethers) and IVG (n = 19; 9 bucks and 10 wethers) were raised on hay and natural grass, and on a commercial pelleted diet to a live weight of 30–35 kg. All goats were slaughtered at a commercial abattoir and the dressed carcasses were chilled at 4 °C within 1 h post mortem. The muscles were dissected from both sides 24 h post mortem and aged for 1 d and 4 d. Variations in meat characteristics such as ultimate pH, water holding capacity (WHC), % purge, myofibril fragment length (MFL), intramuscular fat (IMF), connective tissue characteristics, and Warner-Bratzler shear force (WBSF) were recorded across muscles. Bucks had higher lightness (L*) and hue-angle values, whereas wethers had increased redness (a*) and chroma values. The muscle baseline data will allow informed decisions to support muscle-specific marketing strategies, which may be used to improve consumer acceptability of chevon.

Enhancing Growth Performance, Organ Development, Meat Quality, and Bone Mineralisation of Broiler Chickens through Multi-Enzyme Super-Dosing in Reduced Energy Diets

Simple Summary

The global population is expected to rise from 7.2 billion as of 2019 to 9.7 billion in 2050, putting pressure on farmers to increase production capacity to ensure food security whilst simultaneously improving food sustainability. Poultry is an important meat, as chickens have high feed efficiencies and short production cycles, making it an affordable, nutritious source of protein. Strategies to improve the production performance of broilers will require significant research; one nutritional strategy is improving the efficiency of feed utilization via the addition of exogenous enzymes into diets. This study aimed to identify the optimal multienzyme, Natuzyme, dose rate at three energy levels based on production performance, organ development, meat quality, and bone mineralization in broiler chickens. Results revealed that all dose rates of Natuzyme were able to mitigate the negative effect of energy reductions. Organ development and meat quality remained consistent across treatment groups, except for the gizzard and meat moisture content, which were affected by super-dosing Natuzyme. Bone mineralization was restored with the inclusion of Natuzyme. In conclusion, super-dosing Natuzyme in reduced energy diets at a dose rate of 700 g/t can improve performance parameters and thus profitability for producers and can improve the sustainability of production.

Abstract

This study identified the optimal multi-enzyme dose rate at three energy levels based on the production performance of broiler chickens. A 42-day grow out trial was conducted using 576 day-old mixed-sex ROSS308 broiler chickens in a 3 × 4 factorial arrangement in a completely randomized design. Diets consisting of three metabolizable energy (ME) levels: standard energy (STD), 150 kcal/kg energy reduction (STD-150), and 200 kcal/kg energy reduction (STD-200), were cross factored with four multi-enzyme inclusion levels (0, 350, 700, and 1000 g/ton). The average daily feed intake and feed conversion ratio increased linearly (p < 0.001) as the dietary ME was reduced, and the multi-enzyme addition improved the feed conversion ratio (p < 0.05) and mitigated the negative effect of the reduced energy diets (RED) on feed intake and feed conversion ratios. Carcass composition, organ weights, and meat quality were not affected by the experimental diets. The RED decreased abdominal fat weight (p < 0.05). Total ash, calcium, and phosphorous contents of the tibia bone were improved (p < 0.04) when the RED were supplemented with the multi-enzyme. Super-dosing multi-enzymes in RED mitigates the negative effect of ME reduction on growth performance while maintaining organ development and meat quality and improving bone mineral content.

Variation in the terminology and methodologies applied to the analysis of water holding capacity in meat research

Studies examining meat quality variation, possibly resulting from animal physiology, processing, or ingredient additions, are likely to include at least one measure of water holding capacity (WHC). Methods for evaluating WHC can be classified as direct or indirect. Direct methods either gauge natural release of fluids from muscle or require the application of force to express water. The indirect methods do not actually measure WHC. They attempt to separate meat into two or three categories based on predictions of direct method results: the extreme of high and low WHC and an optional 'normal' group. Considerable statistical analyses are required to generate these predictive models. Presently, there are inconsistent terms (e.g., water holding, WHC, water binding, water binding potential/capacity) used to describe WHC and no standardized techniques recommended to evaluate it. To ensure that results can be compared across different laboratories, a better consensus must be reached in how these terms are employed and how this critical parameter is determined.

Dry-aged beef manufactured in Japan: Microbiota identification and their effects on product characteristics

We aimed to determine the mold, yeast, and bacterial distributions in dry-aged beef (DAB) manufactured in Hokkaido, Japan, and to study their effects on meat quality compared to wet-aged beef (WAB). Two rump blocks from Holstein steer were dry- and wet-aged for 35 days at 2.9 °C and 90% RH. The psychrophilic molds Mucor flavus and Helicostylum pulchrum and other fungi (Penicillium sp. and Debaryomyces sp.) appeared on the crust of DAB, while lactic acid bacteria and coliforms were suppressed in the inner part of the meat. The composition of C16:0, C18:0, and C18:1 fatty acids did not differ between DAB and WAB, while more C17:0 fatty acids were detected in DAB. Dry aging suppressed acids and increased the production of various aroma compounds with mushroom-like, nutty, and other pleasant flavors. The meat quality and free amino acid (FAA) contents of DAB and WAB did not differ significantly. In this study, we identified major molds on DAB, which might contribute to an increase in aroma. Keywords: dry-aged beef; Mucor flavus; Helicostylum pulchrum; psychrophilic mold; meat quality; volatile aroma compounds.

Longissimus Dorsi Muscle Transcriptomic Analysis of Simmental and Chinese Native Cattle Differing in Meat Quality

With the rapid development of economy, the demand for beef, with regard to quantity and quality, by consumers has been increasing in China. Chinese native cattle are characterized by their abundant genetic resources, unique origins, large breeding stocks, and robust environmental adaptability. Thus, to explore the genetic mechanisms on regulating meat quality in Chinese native cattle is of great importance to satisfy increased requirements for beef production. In this study, we investigated three breeds of cattle, namely Yunling, Wenshan, and Simmental, at the age of 12 months. Animals were classified into three groups (n = 5/breed). Growth traits including body weight and body size and plasma hormone levels were measured. Body weight of Wenshan cattle was significantly lower than that of Yunling and Simmental cattle (P < 0.05). Again, body size indexes, such as withers height, body slanting length, chest circumference, and hip and rump length, were significantly lower in Wenshan cattle than those in Yunling and Simmental cattle (P < 0.05). However, there were no significant differences in those indexes between Yunling and Simmental cattle (P > 0.05). Cattle were slaughtered at the age of 18 months and then meat color, pH, pressing losses, muscle tenderness, and cooking losses were measured at 0, 1, 2, 3, 5, and 7 days. Data revealed differences in meat quality among the three breeds analyzed. Based on transcriptomic sequencing and bioinformatic analysis, we observed 3,198 differentially expressed genes related to meat quality, of which 1,750 genes were upregulated. Moreover, we found two important signaling pathways closely linked to meat quality, namely adipocytokine signaling pathway [e.g., Leptin receptor (LEPR)] and protein processing in the endoplasmic reticulum [e.g., signal transducer and activator of transcription 3 (STAT3), heat shock protein (HSPA12A), and calpain 1 (CAPN1)]. The results of transcripts were further verified by qRT-PCR. Using correlation analysis between gene expression levels and shear force, we also identified two functional genes (e.g., HSPA12A and CAPN1) associated with meat quality. Overall, this study provides new sights into novel targets and underlying mechanisms to modulate meat quality in Chinese native cattle.

Technological and nutritional properties of meat from female wild boars (Sus scrofa scrofa L.) of different carcass weights

The aim of this work was to assess the technological and nutritional quality of meat from female wild boars. The muscle samples - Musculus longissimus thoracis et lumborum (LTL) and Musculus semimembranosus (SM) - were taken from a total of 40 female wild boar after a hunt. Carcasses were allocated to five groups according to weight (group I - 30 ± 5  kg; group II - 45 ± 4.9  kg; group III - 60 ± 4.7  kg; group IV - 75 ± 5.2  kg; group V - 90 ± 5  kg). Studies that have been carried out have shown that technological and nutritional properties of meat from wild boars depend on the mass of carcasses and the type of muscle. The pH of analyzed wild boar meat proved that there was normal glycolysis and glycogenolysis progress in all groups. The water holding capacity (WHC) of SM muscles from the lowest-weight carcasses was significantly ( P ≤ 0.01 ) lower as compared to the heavier carcasses. There were significant differences ( P ≤ 0.01 ) in the shear force of the LTL muscle between groups I, IV and V. The muscles cut from carcasses of a higher mass represent higher values of this parameter. The higher-mass carcasses were characterized by a darker color, which resulted from the higher concentration of myoglobin. The protein concentration increased with carcass weight. A similar effect of carcass weight on the content of intramuscular fat (IMF) was found. Due to the low calorie content, the meat of young wild boar may be an interesting and attractive component of the diet.

Enhanced oxidative stability of meat by including tannin-rich leaves of woody plants in goat diet

Objective

The aim of this study was to evaluate the effect of dietary incorporation of tannin-rich woody species on meat oxidative stability, carcass traits and meat quality in goats.

Methods

Two tannin-rich species were tested using a three-treatments feeding trial, where treatments consisted of: Larrea divaricata and Acacia aroma both at 12.5% in dry matter basis of the diet and a control diet (alfalfa hay). All feeding diets were iso-protein and iso-energy. Carcass conformation, carcass compactness, carcass fatness and subcutaneous fat deposition were evaluated. Intake, liveweigh, Longissimus thoracis et lumborum muscles of goats were analyzed in order to evaluate quality parameters such as pH value, instrumental color evaluation, water holding capacity, total phenolic content, antioxidant activity, meat oxidative stability and fatty acid profiles in meat.

Results

Feed intake, liveweight gain, carcass and meat traits did not differ among treatments. Changes in meat lipid profile among treatments were observed for oleic and elaidic acid contents. Meat total phenolic content and antioxidant activity did not differ among treatments; although, meat oxidative status after storage at room temperature, as well as under refrigerated and frozen conditions were different between control and both supplemented groups.

Conclusion

The inclusion of Acacia aroma and Larrea divaricata leaves in goat diet enhanced meat oxidative stability. Modulation of the ruminal biohydrogenation of fatty acids produced by condensed tannins of these plant species need to be further investigated.

Effect of Freezing on the Shelf Life of Salmon

Food shelf-life extension is important not only to food manufacturers, but also to home refrigeration/freezing appliance companies, whose products affect food quality and food waste. While freezing and refrigerating both extend the shelf life of foods, food quality deterioration continues regardless of the preservation method. This review article discusses the global fish market, the composition of fish meat, and the effects of freezing and thawing on salmon quality.

Minimal electrical stimulation is effective in low stressed and well fed cattle

Four groups of carcasses of eighty grain fed low stressed steers (~12 months old, 240 kg carcass weight) received no stimulation or had low voltage stimulation for 15, 45 and 90 s. M. longissimus was aged for 2 and 14 days at 2 °C. Shear force, sarcomere length, water holding capacity, purge, muscle fibre detachment, sarcomere breaks and colour shelf life over 7 days was measured. Both 45 s and 90 s stimulated samples completed rigor above 35 °C and 15s stimulated and non-stimulated samples below 35 °C. The greatest muscle fibre detachment occurred for 15s stimulated samples which were the most tender at all times with non-stimulated samples toughest at 2 days of ageing and all samples being tender at 14 days of ageing. The 45 and 90 s stimulated samples consistently exhibited a brighter red colour at 2 days of ageing with no differences in colour intensity for the samples aged 14 days.

Effect of South African beef production systems on post-mortem muscle energy status and meat quality

Post-slaughter muscle energy metabolism meat colour of South African production systems were compared; steers (n=182) of Nguni, Simmental Brahman crossbreds were reared on pasture until A-, AB-, or B-age, in feedlot until A-AB-age. After exsanguination carcasses were electrically stimulated (400 V for 15 s). M. longissimus dorsi muscle energy samples were taken at 1, 2, 4 and 20 h. Post-mortem samples for meat quality studies were taken at 1, 7 and 14 days post-mortem. Production systems affected muscle glycogen, glucose, glucose-6-P, lactic acid, ATP, creatine-P glycolytic potential (P<0.05), with the muscles of feedlot carcasses having a faster glycolysis rate than pasture carcasses. Energy metabolites correlated (0.4<r<0.9) with meat colour (CIE, L*a*b*), (0.3<r>0.5) water holding capacity, drip loss, and Warner Bratzler shear force. Muscle energy only affected muscle contraction of the A-age-pasture system (shortest sarcomere length of 1.66 μm vs 1.75 μm highest WBS of 6 kg vs 5 kg 7 days post-mortem).

Variation in meat quality characteristics between Sanga (Bos taurus africanus) and Sanga-derived cattle breeds and between Sanga and Brahman (Bos indicus)

Cattle breeds indigenous to Africa (Sanga) compare favourably to Bos indicus breeds with regard to adaptation to harsh environments. This study compared the meat quality of three Sanga breeds (Nguni, Tuli and Drakensberger), a Sanga-related breed (Bonsmara) and a B. indicus breed (Brahman) and supported these results with biochemical and histological measurements on the M. longissimus lumborum. Twelve young grain-fed steers of each breed were slaughtered and carcasses were electrically stimulated. All Sanga (and related) breeds, with the exception of the Tuli, had lower Warner-Bratzler shear force (SF) values at 2 and 21 days post mortem compared with the BR (P < 0.05). Measurements related to the calcium-dependent protease system and myofibrillar fragmentation explained the bulk of the variation among breeds, whereas variation in fibre type, sarcomere length and connective tissue properties gave less convincing support. With the exception of the Tuli, Sanga and Sanga-related breeds produced more tender (according to SF) meat than BR, mainly due to favourable calpain-to-calpastatin ratios. Small differences in colour, drip loss and cooking properties were found among breeds (P < 0.05).

Growth performance, feed efficiency and carcass and meat quality of tropically adapted breed types from different farming systems in South Africa

Two experiments measured the ability of tropically adapted beef breeds from resource-poor farmer herds in South Africa to produce high quality beef under commercial feedlot conditions. The resource-poor farming sector consists of ‘emerging’ and communal farmers. The herd and breed groups consisted of Sanga types (tropically adapted Bos taurus breed) including Nguni, Tuli, Bonsmara and Drakensberger, as well as Brahman and non-descript groups. The cattle were slaughtered after an average of 97 days in the first experiment and after an average of 92, 140 and 169 days on a grain-based diet in the second experiment. Growth performance, carcass quality and yield, occurrence of disease and meat quality were measured. The performance of the breeds groups was a function of their genetic potential and herd type (carcass weight and condition at arrival). Steers from emerging and communal farmer herds enter the feedlot at a lighter weight, but show similar growth performance to achieve acceptable, albeit lighter carcass weights, than their commercial counterparts. The incidence of disease was no different between commercial, emerging and communal herds. Carcass and meat quality analyses indicate small or no differences between herd types or breeds, except that Brahman produced tougher meat. It was concluded that cattle from resource-poor farmer herds have the ability to meet the specifications of South Africa’s commercial beef markets, indicating a genuine opportunity for import substitution, whereby the more than 5 million cattle in resource-poor farmer herds could be used to overcome the significant shortfall in South Africa’s domestic beef market demand.