Traditional halal meat production without stunning versus commercial slaughter with electrical stunning of slow-growing broiler chicken: impact on meat quality and proteome changes.

Impact of traditional halal meat production without stunning (NST) and commercial slaughter with electrical stunning (ST) of 100 slow-growing broiler chicken on blood plasma and different biochemical, enzymatic, hormonal, meat quality, and proteomic changes was evaluated. The results revealed lower (P < 0.05) postmortem pH values and higher redness (a*) scores for ST samples relative to NST group. Myofibrillar fragmentation index and bleeding efficiency (%) were lower (P < 0.05) in ST compared to NST samples. The ST group had higher (P < 0.05) creatinine, total protein, alanine aminotransferase (ALT), and triiodothyronine (T3) than NST group, however, no difference (P > 0.05) in blood glucose, lactate dehydrogenase (LDH), creatine kinase (CK), thyroxine (T4), cortisol, and aspartate aminotransferase (AST) was observed relative to NST samples. The 2-dimensional gel electrophoresis (2-DE) coupled to MALDI-TOF MS of meat samples has identified 14 differentially abundant proteins between 2 groups. Proteins demonstrating positive correlation with stress namely adenylate kinase isoenzyme-1, Rho guanine nucleotide exchange factor (NST), and apolipoprotein A-I (ST) were overabundant. From the current study, it is concluded that electrical stunning of broilers prior to slaughter or traditional halal slaughter without stunning does not adversely affect the meat quality.

Lateral flow immunoassay-based absolute point-of-care technique for authentication of meat and commercial meat products.

Point-of-care (POC) assay is an emerging technique for rapid initial screening of meat fraud incidents in a resource-limited environment. To achieve this goal, a simple extraction protocol is proposed for efficient recovery of meat proteins from raw, heat-processed, and commercial samples as well as meat offals without utilizing sophisticated laboratory settings. A sandwich-format lateral flow immunoassay (LFIA) was developed based on gold nanoparticles as labels and immunoglobulins (IgG and IgY) as biomarkers for meat species identification in raw and cooked meat mixes. The test system showed a sensitivity of 10 ng/mL allowing the detection of as low as 0.063% pork and chicken meat and 0.125% sheep meat (lamb) in meat mixes within 15 min including sample preparation. Reproducibility of the assay was confirmed by the fully consistent intra- and inter-laboratory tests and RT-PCR method. The current study developed a field-deployable extraction technique and highly-specific, sensitive, reproducible, cost-effective, and user-friendly LFIA-based assay for rapid species authentication in raw, cooked, and commercial meat samples and meat offals. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05663-2.

Antioxidant and angiotensin-I-converting enzyme (ACE-I) inhibitory activities of protein hydrolysates derived from water buffalo (Bubalus bubalis) liver.

In the current study, we attempted to use ginger as a novel and natural source of protease in comparison with other commercially available enzymes to extract and characterize antioxidant and antihypertensive hydrolysates from water buffalo liver, a protein rich offal. Hydrolysis of protein extracts from buffalo liver using proteinase-K, pronase-E and ginger protease significantly increased the %degree of hydrolysis (18.5-55%) and generated low-molecular weight peptides evident from SDS-PAGE. Enzyme treated hydrolysates exhibited higher (p < 0.05) DPPH radical scavenging activity (43.7-82.4%) and angiotensin-I-converting enzyme (ACE-I) inhibitory activity (46.9-50.1%) relative to control. Mass spectrometric analysis (MALDI-TOF MS) of selected gel-filtered fractions identified few important peptides derived from nuclear ribonucleoprotein, pyruvate kinase and phosphoglycerate kinase that possess strong antioxidant activity. Present findings indicate the efficacy of partially purified ginger as a novel source of protease in generating protein hydrolysates from water buffalo liver with significant antioxidant and antihypertensive activity in vitro. We successfully demonstrated the recovery of functional bioactive peptides from water buffalo liver which presents a potential opportunity for the meat industries to economically use this important byproduct.

Impact of stunning before slaughter on expression of skeletal muscles proteome in sheep.

The commercial production of halal and kosher meat and controversy surrounding the slaughter without stunning is rapidly growing across the globe. Huge global market for halal and kosher meat warrants conciliation of religious practices and animal welfare for the betterment of meat industry. In the present study, we investigated changes in muscle proteome of sheep (Ovis aries) subjected to either electrical stunning and slaughtering or slaughter without any stunning (halal). The 2DE gel analysis detected approximately 377 protein spots in which 243 (119 up regulated and 124 down regulated) protein spots were significantly (p ≤ 0.05) differentially expressed with a fold change ratio ≥1.5/≤1.5. The in-gel digestion and MALDI-TOF/TOF MS analysis of statistically significant protein spots revealed 35 differentially abundant proteins out of which 26 were up-regulated and 9 were down-regulated. The study demonstrated that slaughtering of sheep without stunning resulted in changes in the abundance of proteins involved in catalytic, structural, and stress related processes. This understanding of protein alterations in sheep slaughtered with and without stunning have the potential to act as possible signature for animal welfare index.

Exploring the dynamics of women consumer preference, attitude and behaviour towards meat and meat products consumption in India.

Urbanisation and changing food habits in India have resulted in a shift in consumption from cereals to protein-based foods. Women play a major role in India in all activities related to food at household and therefore, the current paper reports the findings of the qualitative work conducted to understand women consumers' preference and perception towards meat and its attributes as a function of their awareness. The study collected the responses from 510 women residents of Metropolitan city of Bengaluru, India using questionnaires directly by face-to-face interviews and generated data on preference for fresh meat, purchase habits, value added meat products consumption, awareness about meat quality, and future expectations about meat sector. Findings from the current study indicate that, chicken is the most preferred meat (41.76%) while beef was least preferred (5.88%). The 40.59% of respondents preferred meat tenderness as an important eating quality followed by juiciness (37.06%) and flavor (12.94%). Consumers rated ritual slaughter, animal welfare and food safety as relevant issues in meat production, whereas regulations pertaining to meat production, processing of meat and food labelling were of minor significance. The study provide an insight into the significance of various consumer behaviour with respect to choice of meat, awareness on ritual slaughter, animal welfare and processing which is helpful in prioritizing future consumer research and policy decisions in India.

Proteomic based approach for characterizing 4-hydroxy-2-nonenal induced oxidation of buffalo (Bubalus bubalis) and goat (Capra hircus) meat myoglobins.

BACKGROUND: Myoglobin (Mb) is a sarcoplasmic heme protein primarily responsible for meat color and its chemistry is species specific. 4-hydroxy-2-nonenal (HNE) is a cytotoxic lipid derived aldehyde detected in meat and was reported to covalently adduct with nucleophilic histidine residues of Mb and predispose it to greater oxidation. However, no literature is available on characterization of lipid oxidation induced oxidation of Indian water buffalo (Bubalus bubalis) and goat (Capra hircus) myoglobins. METHODS: Present study characterize the Mb extracted from water buffalo and goat cardiac muscles using two-dimensional gel electrophoresis (2DE), OFFGEL electrophoresis and mass spectrometry (MS). Purified buffalo and goat bright red oxymyoglobin were reacted with HNE in-vitro at physiological pH (7.4) and temperature (37 °C) conditions and the formation of oxidised brown metmyoglobin was measured. The Mb-HNE adducts were detected using MALDI-TOF MS, whereas specific sites of adduction was determined using ESI-QTOF MS/MS. RESULTS: Purified buffalo and goat Mb samples revealed a molecular mass of 17,043.6 and 16,899.9 Daltons, respectively. The 2DE analysis exhibited 65 (sarcoplasmic protein extract) and 6 (pure Mb) differentially expressed (P < 0.05) protein spots between buffalo and goat samples. OFFGEL electrophoresis revealed an isoelectric point of 6.77 and 7.35 respectively, for buffalo and goat Mb's. In-vitro incubation of HNE with bright red buffalo and goat oxymyoglobin's at pH 7.4 and 37 °C resulted in pronounced (P < 0.05) oxidation and formation of brown metmyoglobin. MALDI-TOF MS analysis of Mb-HNE reaction mix revealed covalent binding (via Michael addition) of 3 and 5 molecules of HNE with buffalo and goat Oxy-Mb's, respectively. ESI-QTOF MS/MS identified seven and nine histidine (HIS) residues of Mb that were readily adducted by HNE in buffalo and goat, respectively. CONCLUSION: The study demonstrated better redox stability of buffalo Mb than goat Mb. Our findings confirm the hypothesis that relative effect of HNE was greater for Mb's with 12 ± 1 HIS residues than Mb's with 9 HIS residues and helps meat processors in developing species-specific processing strategies to reduce the color variability.

Redox instability and hemin loss of mutant sperm whale myoglobins induced by 4-hydroxynonenal in vitro.

The effects of 4-hydroxy-2-nonenal (HNE) on redox stability of Oxy- and Deoxy- wild-type (WT) and recombinant sperm whale myoglobins (P88H/Q152H, L29F, H97A, and H64F) and hemin loss from Met-myoglobin (Mb) were investigated. HNE induced greater redox instability in WT and mutant Mbs compared to controls (p < 0.05). The extent of HNE-induced OxyMb oxidation was lesser in L29F (p < 0.05) and greater in H97A and P88H/Q152H than in WT (p < 0.05). H64F DeoxyMb was more redox stable than WT DeoxyMb in the presence of HNE (p < 0.05). HNE alkylation occurred exclusively on histidine residues, and histidine 48 was alkylated in all sperm whale myoglobins. HNE alkylation accelerated the protoporphyrin moiety loss only in H97A. Met- forms of WT and L29F but not Deoxy- or Oxy- forms released hemin during storage. Primary structure strongly influenced Mb redox stability in the presence of reactive secondary lipid oxidation products.

Species-specific myoglobin oxidation.

The effect of the lipid oxidation product, 4-hydroxy-2-nonenal (HNE), on oxidation of oxymyoglobin (OxyMb) from seven different meat-producing species was investigated. Relative to controls, HNE increased OxyMb oxidation within all species (p < 0.05) at both 25 and 4 °C, pH 5.6. The relative effect of HNE was greater for myoglobins (Mbs) that contained 12 ± 1 histidine (His) residues than for those that contained 9 His residues (p < 0.05); HNE efficacy in all species except chicken and turkey decreased with time. Mono-HNE adducts were detected in all species except chicken and turkey. In general, HNE alkylation increased the Mbs' ability to accelerate lipid oxidation in a microsome model. However, neither an HNE nor a Mb species dependent effect was observed. Results suggested that microsome model system associated lipid oxidation overshadowed HNE and species effects on OxyMb oxidation observed in lipid-free systems.

Effects of lactate on bovine heart mitochondria-mediated metmyoglobin reduction.

Our objective was to determine the combined effects of lactate, LDH, and NAD on metmyoglobin reduction in mitochondria isolated from bovine cardiac muscle. Mitochondria were reacted with various combinations of lactate, LDH, NAD, and mitochondrial inhibitors, and oxygen consumption was measured using a Clark oxygen electrode. Mitochondria (3 mg/mL) and bovine metmyoglobin (0.15 mM) also were reacted with substrates/enzymes/inhibitors to determine mitochondria-mediated metmyoglobin reduction in vitro. Combining lactate-LDH-NAD with isolated mitochondria increased oxygen consumption as well as metmyoglobin reduction compared with those of either control mitochondria (without lactate) or mitochondria with added lactate, at pH 5.6 and 7.4 (p < 0.05). The addition of mitochondrial and LDH inhibitors to lactate-LDH-NAD decreased oxygen consumption and metmyoglobin reduction (p < 0.05). NADH formed from lactate-LDH-NAD can be used for nonenzymatic (via the electron transport chain) and enzymatic (NADH-dependent metmyoglobin reductase) metmyoglobin reduction.

Mass spectrometric characterization and redox instability of turkey and chicken myoglobins as induced by unsaturated aldehydes.

Turkey and chicken myoglobins (Mbs) were isolated, purified, and characterized using electrospray ionization mass spectrometry (ESI-MS), and the effect of unsaturated aldehydes (nonenal and hexenal) on their redox stability was investigated in vitro. The deconvoluted spectra from ESI-MS exhibited a molecular mass of 17291 Da for both turkey and chicken Mbs. Significant homogeneity in the fragmentation pattern of both Mbs was indicated by ESI-MS/MS. Both turkey and chicken oxymyoglobins (OxyMbs) were more prone to oxidation at pH 5.8 than at pH 7.4. Metmyoglobin formation was greater in the presence of unsaturated aldehydes than controls (P < 0.05). The results demonstrated that both turkey and chicken Mbs have identical molecular mass and that the effects of alpha,beta-unsaturated aldehydes on their redox stability are consistent with those of mammalian livestock Mbs.