Assessment of beef sensory attributes and physicochemical characteristics: A comparative study of intermediate versus normal ultimate pH striploin cuts

The quality of beef, defined by key attributes such as the intrinsic sensory qualities texture, flavour, and juiciness, is shaped by various intrinsic and extrinsic factors. This study conducted a detailed examination of Nellore beef, focusing on two categories based on ultimate pH (pHu) levels: intermediate (pHu ≥ 5.8) and normal (pHu < 5.6) beef. A comprehensive approach was taken, involving twenty trained assessors who applied the Optimised Descriptive Profile (ODP) method to evaluate grilled striploin steak samples. In parallel, consumer preferences were measured through a hedonic test and a Check-all-that-apply (CATA) task, involving 135 participants. The ODP results revealed that the intermediate pHu samples were juicier (P < 0.05) compared to the normal pHu group. The CATA analysis highlighted differences in both intermediate and normal pHu beef, especially in juiciness, a crucial factor for consumer satisfaction. Notably, variations in deoxymyoglobin content linked to ageing were observed, with higher levels at the 3rd day compared to the 28th day, especially in the intermediate pHu samples (P < 0.05). Moreover, colour-related aspects such as L*, b*, chroma (C*), and oxymyoglobin were significantly influenced (P < 0.05) by both the pHu category and ageing time. Regarding consumer acceptance, the study found no significant difference in perception between the intermediate and normal pHu groups (P > 0.05). These findings revealed the complex interactions between pHu levels, sensory characteristics, and consumer preferences in beef quality, offering valuable insights for both the industry and research community.

Effect of ultimate pH on quality of aged Longissimus dorsi muscle of Zebu Nellore (Bos indicus) during long-term frozen storage

Despite the relatively high occurrence of bovine meat with intermediate to high ultimate pH (pHu), there is a lack of studies focused on the effects of long-term conventional air-blasting freezing storage on quality parameters of commercial beefs of Zebu Nellore (Bos indicus) with varying pHu ranges. The objective of this work was to evaluate the influence of pHu ranges [normal (≤5.79), intermediate (5.80 to 6.19), and high (≥6.20)] and long-term frozen storage on quality parameters of aged Longissimus dorsi beefs of Zebu Nellore (Bos indicus). The aging conditions were set at 2 °C for 14 days, while the freezing conditions were set at - 20 °C, and samples were collected after 3, 6, 9, and 12 months of storage. The results indicated that the pHu influenced meat quality parameters, as well as the chemical forms of myoglobin, which changed throughout the frozen storage, leading to a brighter red color, especially for the normal pHu beef samples, likely due to increased oxymyoglobin content. Frozen storage improved tenderness, with high pHu beef samples being the more tender after 12 months, potentially due to lower protein oxidation, as measured by the carbonyl content. Increased drip loss was observed over freezing time, with a concomitant decrease in protein solubility, especially for myofibrillar and sarcoplasmic proteins, which differed among the pHu ranges. These findings are valuable for determining freezing time as a preservation strategy to maintain beef quality within different pHu ranges.

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.

Effects of altitude on meat quality difference and its relationship with HIF-1α during postmortem maturation of beef

This study investigated the differences in meat quality during postmortem aging of yak meat from different altitudes as well as the relationship between the release of hypoxic factor HIF-1α and meat quality. The results showed that the HIF-1α increased with altitude but during aging process, there was an initial increase before a subsequent decrease (p < .05). Moreover, significant increases were showed in glycolytic potential, a* value, pH, HIF-1α mRNA expression, HIF-1α protein expression and shear force with altitude (p < .05). Additionally, the b* value, L* value, water holding power and MFI decreased significantly (p < .05). HIF-1α was shown, by PLS-DA method analysis, to be the main protein marker for differences in the quality during aging time of meat from three altitude groups. HIF-1α protein expression was high correlated with glycolytic potential, pH value, meat color, tenderness and water holding capacity during postmortem aging. The results demonstrated that HIF-1α is a novel marker protein that influences meat quality in yak from different altitudes and that HIF-1α-mediated glycolytic pathway was key to the meat quality during postmortem aging. PRACTICAL APPLICATIONS: Yak meat has the advantages of high protein, low fat, good amino acid and fatty acid composition, so the nutritional value of yak meat is in line with the current best-selling beef with less fat in domestic and foreign markets. But consumers often think that the meat tenderness of yak meat is worse than that of beef and improving the quality of yak meat was worthy of attention specifically. This study investigated the differences in meat quality during postmortem aging of yak meat at different altitudes and the relationship between hypoxic factor HIF-1α release and meat quality.

Effect of packaging and storage conditions on some quality traits of bovine meat

Packaging is considered one of the most interesting technological aspects of food production and is a constantly evolving subject in food production. The type of packaging is important for the quality and safety of the product and for the visual appearance of the product to be immediately evaluated by consumers. The purpose of this study was to investigate the effect of four different types of modified atmosphere packaging (ATM) and vacuum packaging (VP) currently used by a company in central Italy, on the main qualitative characteristics of beef. For these two traditional and two new solutions with reduced environmental impact and compostable were evaluated. For each type of packaging, two different products were analyzed: steaks and hamburgers. The samples, immediately after production, were transported to the laboratory in refrigerated containers. Several parameters (color, pH, water holding capacity, drip loss, and microbiological characteristics) were evaluated at time 0 and after 7 (T7), 14 (T14) and 21 days (T21) of storage in the dark and at refrigeration temperature (+4°C ± 2°C). The results showed that the two types of packaging have very similar effects on the water-retaining capacity of the steaks. More noticeable differences were recorded by the colorimetric analysis: for both steaks and hamburgers, the products packaged in the traditional packaging appeared brighter and redder than those packaged in the new alternatives. The microbiological analysis of the steaks showed higher values in the “new” packaging. The formation of abundant ropy slime was observed in one of the samples in the “new” modified atmosphere package at T21. The results of this study showed that the technological characteristics (in particular, the color) and the microbiological characteristics of the steaks and hamburgers were better in “old” packaging, with a better appearance and a longer shelf life. The results obtained show how the research for eco-sustainable products for packaging must be addressed, taking into account the effect of the materials on the qualitative and hygienic- sanitary characteristics of the meat.

The investigation of storage situation of fish muscle via the analysis of its exudate by MALDI-TOF MS

The potential of MALDI-TOF MS was investigated in terms of its capability to determine the change of exudates of fish muscle with different freeze-thaw cycles (0, 1 and 2), and frozen storage periods. The exudates were collected from dead chilled marine fish species, large yellow croacker (Larimichthys crocea, LC) and freshly slaughtered freshwater fish species, Japanese seabass (Lateolabrax japonicus) to be studied as models. 109 proteins, in which, 32 are extracellular proteins, and 15 are intracellular proteins, were identified by analyzing exudate of LC using MALDI-TOF MS and HPLC-MS/MS. The results show that the present method may be able to determine the change of fish muscle foods in a more sensitive mode than K value indicated quality control. The feasibility of verifying the storage situation of fish sample was performed by analyzing fish samples obtained from the local market. It is promising to estimate the storage situation of fishery products or other animal muscle foods by analyzing their muscle exudates based on the presently developed strategy.

Effects of Dietary Perilla Cake Supplementation in Growing Pig on Productive Performance, Meat Quality, and Fatty Acid Profiles

The objective of this study was to determine the effect of perilla cake (PC) supplementation in a growing pig diet on overall growing performance, meat quality, and fatty acid profile. A total of 24 barrow grower crossbred pigs (Large White × Landrace) × Duroc with an initial average body weight of 26.33 kg were fed with a basal diet supplemented with PC at 0%, 5%, and 10% in (PC0, PC5, and PC10, respectively) for 12 weeks. At the end of the experimental period, pigs were slaughtered to determine carcass traits and meat quality. Back fat, abdominal fat, and longissimus dorsi (LD) muscle were collected to investigate fatty acid composition. The results show that the average daily gain (ADG) in the PC10 significantly increased. However, PC supplementation did not influence carcass traits and meat quality except the color as described by lightness (L*). Dietary PC supplementation significantly increased the α-linolenic acid (ALA, C18:3 cis-9, 12, 15), whereas n6/n3 ratio decreased significantly in all tissues investigated. Thus, it can be concluded that the supplementation of PC in growing pig diet is a potential way to increase the fatty acid composition to that required for healthier meat.

EZ-DripLoss Assessment in Chicken Breast Meat Using Different Sample Areas, Fiber Orientation, and Measurement Intervals

Although the EZ-DripLoss method has been performed in numerous studies, there is a deficiency in our knowledge of the EZ-DripLoss method's suitability for poultry meat analysis. This study aimed to research the effect of different sample areas (10, 20, and 30 mm; n = 240), and fiber orientations (vertical vs. horizontal) on the EZ-DripLoss in chicken breast meat measured across a period of five days. The influence of sample area on the EZ-DripLoss of chicken breast meat with respect to the fiber orientation and across the five-day measurement interval was significant between 10 and 30 mm samples, and between 20 and 30 mm samples (p < 0.001). The estimated regression coefficient showed that EZ-DripLoss for the samples with horizontal and vertical fiber direction of 10 and 20 mm, significantly increased by 0.04% per hour, while for the samples with vertical fiber direction whose diameter was 30 mm, it significantly increased by 0.06% per hour, and for the horizontal fiber direction, it significantly increased by 0.07% per hour. The samples with vertical fiber orientation had 0.50% greater EZ-DripLoss compared to the samples with horizontal fiber orientation. EZ-DripLoss evaluation in chicken breast should be performed with a sample core diameter of 20 mm, a vertical fiber orientation, and over the course of longer measurement intervals.

Drip loss assessment by EZ and bag methods and their relationship with pH value and color in mutton

Drip loss, pH value, and color are among the important traits that determine meat quality. Contrary to pH and color, the method associated with drip loss is not yet standardized, and literature data are difficult to compare. Besides, to our knowledge, there is no research comparing drip loss methods and their relation with pH and color in mutton. This study aimed to assess drip loss measurements in mutton taken by different methods (EZ and bag – BM) and their relationship with pH values and color. Mutton samples (Musculus longissimus thoracis et lumborum) originating from 20 ewes of Istrian sheep were used to examine the effect of the method on drip loss after 24 h (EZ24 vs. BM24) and 48 h (EZ48 vs. BM48). Furthermore, correlations between drip loss, pH value, and color were analyzed. The statistical analysis was conducted in R programming environment by using different packages. Within the EZ method there was no significant difference (p>0.05) between ventral and dorsal sample cores used for the assessment of EZ drip loss. Drip loss measured with the same method at two different points of time (24 and 48 h) differed significantly (p<0.001). There was also a significant difference in drip loss determined by different methods (EZ vs. BM) at the same point of time. There were significant (p<0.05) correlations between pH45min and all color parameters (L*4, a*, b*). The L*, a*, and b* parameters were highly correlated (p<0.001). The strongest correlation occurred between a* and b* parameter (r=0.93). Correlations between drip loss by EZ method and other meat quality attributes were low and not significant. The b* parameter correlated with BM24 (r=0.46) and BM48 (r=0.58), while a* correlated only with BM48 (r=0.50). The correlations between the EZ24 and BM24 as well as between the EZ48 and BM48 were both non-significant (p>0.05). Drip loss cannot be predicted with sufficient accuracy by using pH and color. EZ and BM method in mutton do not provide equivalent results for measuring drip loss. Comparisons of the results obtained with different methods should be avoided or at least performed with great precaution.

TMT-based quantitative proteomic analysis of porcine muscle associated with postmortem meat quality

To explore the molecular mechanisms of meat quality, four high-quality (HQ) samples and four low-quality (LQ) samples from longissimus dorsi muscles were chosen, and tandem mass tag (TMT) labeling combined with mass spectrometry (MS) were performed to find associations between meat quality and proteome profiles. The LQ meats had lower pH, lighter color, and higher drip loss compared to the HQ meats. About 140 differentially expressed proteins were identified. Functional analysis results of differentially expressed proteins showed that decreased release of Ca²⁺, lower contents of type II fibers, lower contents of glycogen, and decreased glycogenolysis in HQ meats indicated a lower degree of glycolysis in HQ as compared to LQ meats. Meanwhile, some differentially expressed proteins suggested that the levels of oxidative stress and apoptosis were lower in HQ meats than in LQ meats. This study reveals physiological changes between HQ and LQ meats according to the proteome profiles.

Effect of Dietary Modulation of Selenium Form and Level on Performance, Tissue Retention, Quality of Frozen Stored Meat and Gene Expression of Antioxidant Status in Ross Broiler Chickens

Simple Summary

Although the importance of usage of selenium as essential trace element in poultry production has been proven, the best source and level has not been fully addressed yet. Three different dietary selenium forms with three different levels were chosen to be added in broiler diet. Met-Se or nano-Se up to 0.6 mg/kg increased their performance and was more efficiently retained in the body than SeS. Frozen stored meat quality was improved in a dose-dependent manner especially with both Met-Se and nano-Se. Nano-Se was more potent than Met-Se, which in turn was more potent than inorganic Se against oxidative stress, which improved the quality of meat under frozen conditions.

Abstract

This study compares between different selenium forms (sodium selenite; SeS, selenomethionine; Met-Se or nano-Se) and levels on growth performance, Se retention, antioxidative potential of fresh and frozen meat, and genes related to oxidative stress in Ross broilers. Birds (n = 450) were randomly divided into nine experimental groups with five replicates in each and were fed diets supplemented with 0.3, 0.45, and 0.6 mg Se/kg as (SeS, Met-Se), or nano-Se. For overall growth performance, dietary inclusion of Met-Se or nano-Se significantly increased (p < 0.05) body weight gain and improved the feed conversion ratio of Ross broiler chicks at the level of 0.45 and 0.6 mg/kg when compared with the group fed the same level of SeS. Se sources and levels significantly affected (p < 0.05) its concentrations in breast muscle, liver, and serum. Moreover, Se retention in muscle was higher (p < 0.05) after feeding of broiler chicks on a diet supplemented with Met-Se or nano-Se compared to the SeS group, especially at 0.6 mg/kg. Additionally, higher dietary levels from Met-Se or nano-Se significantly reduced oxidative changes in breast and thigh meat in the fresh state and after a four-week storage period and increased muscular pH after 24 h of slaughter. Also, broiler’s meat in the Met-Se and nano-Se groups showed cooking loss and lower drip compared to the SeS group (p < 0.05). In the liver, the mRNA expression levels of glutathione peroxidase, superoxide dismutase, and catalase were elevated by increasing dietary Se levels from Met-Se and nano-Se groups up to 0.6 mg/kg when compared with SeS. Therefore, dietary supplementation with 0.6 mg/kg Met-Se and nano-Se improved growth performance and were more efficiently retained than with SeS. Both sources of selenium (Met-Se and nano-Se) downregulated the oxidation processes of meat during the first four weeks of frozen storage, especially in thigh meat, compared with an inorganic source. Finally, dietary supplementation of Met-Se and nano-Se produced acceptable Se levels in chicken meat offered for consumers.

Effects of PSE meat and salt concentration on the technological and sensory characteristics of restructured cooked hams

The effects of the use of normal and pale, soft, and exudative (PSE) meat on the technological and sensorial quality of restructured cooked hams elaborated with different salt contents (0.8, 1.2, 1.6, 2.0, and 2.4%) were investigated. A low salt content implied (P < .05) high cooking loss (6.27 vs 3.25%), expressive moisture and C* values and low hardness. Products elaborated with PSE meat had (P < .05) lower cohesiveness, energy to fracture and hue tone colour and higher springiness than did samples elaborated with normal meat. Salty taste perception was slightly higher for the PSE meat-based products, which were also preferred by the assessors when salt contents lower than 1.6% were used. It was concluded that when PSE meat was used, the addition of 1.2% salt was sufficient to maintain the technological and sensory characteristics of the restructured cooked hams.