Enhancing agro-biodiversity in chicken: a sensory comparison of broths from German local chicken breeds and their crossbreeds.

The poultry meat production landscape has undergone a reduction in chicken breeds, resulting in a reliance on a limited number of varieties. Motivated by the goal of promoting sustainable chicken production and enhancing agro-biodiversity, this study pioneers a comparison between local chicken breeds (LB) and their crossbreeds (CB) with modern hybrid lines. Serving as an initial exploration within a larger project, this research acts as a prelude to a comprehensive investigation, aiming to complement the human sensory assessment of product quality. Study I assessed chicken broths prepared from 3 German LBs Bielefelder (BIE), Altsteirer (ALT), and Ramelsloher (RAM) utilizing a factorial 3 × 2 × 2 design that incorporated variations in salt content (unsalted/salted) and cooking time (1 h/3 h). The sensory profiles of the LB broths were largely similar, except for BIE, which exhibited a higher skin odor intensity. Both, increased salt content and longer cooking time intensify sensory perception on most attributes. In study II, BIE was compared with 6 CBs, with variations in salt content and cooking time (6 × 2 × 2 + 1 × 2 factorial design). BIE demonstrated higher sensory intensities than the CBs. Those were comparable, with no clear advantages or disadvantages identified from a sensory standpoint. These findings support that crossbreeding with commercial lines is not associated with changes in the sensory profile. It thus represents a strategy for improving the economic viability of local chicken breeds in order to preserve their valuable agro-biodiversity. The provided protocol for evaluating chicken broth from LBs or their CBs aims to offer researchers a standardized foundation for sensory assessments in chicken broth studies.

Meta-analysis of citrus-derived additives on chicken meat quality and safety: a comprehensive evaluation of acceptability, physicochemical properties, and microbial contamination.

Citrus represents a valuable repository of antioxidant substances that possess the potential for the preservation of meat quality. This meta-analysis aimed to comprehensively assess the impact of citrus additives on the quality and safety of chicken meat. Adhering to the PRISMA protocol, we initially identified 103 relevant studies, from which 20 articles meeting specific criteria were selected for database construction. Through the amalgamation of diverse individual studies, this research provides a comprehensive overview of chicken meat quality and safety, with a specific focus on the influence of citrus-derived additives. Minimal alterations were observed in the nutritional quality of chicken meat concerning storage temperature and duration. The findings demonstrated a significant reduction in aerobic bacterial levels, with Citrus aurantiifolia exhibiting the highest efficacy (P < 0.01). Both extracted and nonextracted citrus components, applied through coating, curing, and marinating, effectively mitigated bacterial contamination. Notably, thiobarbituric acid reactive substances (TBARS) concentrations were significantly reduced, particularly with Citrus hystrix (P < 0.01). Total volatile base nitrogen (TVBN), an indicator of protein degradation, exhibited a decrease, with citrus extract displaying enhanced efficacy (P < 0.01). Chemical composition changes were marginal, except for a protein increase after storage (P < 0.01). Hedonic testing revealed varied preferences, indicating improvements in flavor, juiciness, and overall acceptability after storage (P < 0.01). The study underscores the effectiveness of citrus additives in preserving chicken meat quality, highlighting their antibacterial and antioxidant properties, despite some observed alterations in texture and chemical composition. Citrus additives have been proven successful in 1) mitigating adverse effects on chicken meat during storage, especially with Citrus hystrix exhibiting potent antimicrobial properties, and 2) enhancing the hedonic quality of chicken meat. This research strongly advocates for the application of citrus additives to uphold the quality and safety of chicken meat.

Quality Enhancement of Frozen Chicken Meat Marinated with Phosphate Alternatives.

The effects of phosphate alternatives on meat quality in marinated chicken were investigated with the application of chilling and freezing. Breast muscles were injected with solution of the green weight containing 1.5% NaCl and 2% sodium tripolyphosphate (STPP) or phosphate alternatives. Treatment variables consisted of no phosphate [control (-)], 0.3% sodium tripolyphosphate [control (+)], 0.3% prune juice (PJ), 0.3% oyster shell, 0.3% nano-oyster shell, and 0.3% yeast and lemon extract (YLE) powder. One-third of the meat samples were stored at 4°C for 1 d, and the rest of the meats were kept at -18°C for 7 d. In chilled meat, a lower drip loss was noted for control (+) and YLE, whereas higher cooking yield in YLE compared to all tested groups. Compared with control (+), the other treatments except PJ showed higher pH, water holding capacity, moisture content, lower thawing and cooking loss, and shear force. Natural phosphate alternatives except for PJ, improved the CIE L* compared to control (-), and upregulated total protein solubility. However, phosphate alternatives showed similar or higher oxidative stability and impedance measurement compared to control (+), and an extensive effect on myofibrillar fragmentation index. A limited effect was observed for C*, h°, and free amino acids in treated meat. Eventually, the texture profile attributes in cooked of phosphate alternatives improved except for PJ. The results indicate the high potential use of natural additives could be promising and effective methods for replacing synthetic phosphate in chilled and frozen chicken with quality enhancement.

Effects of serum aspartate aminotransferase activity on levels of serum Ca2+, Ca2+ channel genes, apoptotic factors, and meat quality characteristics of chicken pectoralis major muscle.

This study investigated the association between serum aspartate aminotransferase activity and apoptotic potentials assessed by the levels of serum parameters, including Ca2+ and serotonin, Ca2+ channel genes, and caspase genes, at the early postmortem. Additionally, the effect of serum aspartate aminotransferase activity on meat and sensory quality characteristics of chicken pectoralis major muscle was investigated to determine the cause of meat quality deterioration. Among the groups categorized by serum aspartate aminotransferase activity, the high group showed a higher serotonin level and a lower Ca2+ level than the low and medium groups (P < 0.05). The low group had higher apoptotic potentials as exhibited higher levels of ryanodine receptor, sarco/endoplasmic reticulum Ca2+-ATPase, and caspases than the high group (P < 0.05). The low and medium groups showed lower pH24 h and paler surface color than the high group (P < 0.05), indicating pale, soft, and exudative-like meat. Sensory juiciness and overall acceptability were higher in the high group than in the low group (P < 0.05). Overall, serum aspartate aminotransferase activity may be a useful indicator for explaining the meat quality variation, as this molecule can prevent deterioration of chicken meat quality.

Research Note: Comparison of histochemical characteristics, chicken meat quality, and heat shock protein expressions between PSE-like condition and white-stripping features of pectoralis major muscle.

The present study compared the histochemical and meat quality characteristics of broiler pectoralis major (PM) muscle among the groups categorized according to muscle abnormalities, including pale, soft, and exudative (PSE)-like condition and white-striping (WS) feature. Additionally, this study investigated the associations between muscular abnormalities and expression levels of heat shock proteins (HSPs), including αß-crystallin, HSP70, and HSP90, at the early postmortem period. The WS breasts with normal quality condition showed greater PM muscle weight and were more associated with fiber hypertrophy, compared to the no WS breasts with PSE-like condition (P < 0.05). The PSE-like group exhibited paler surface color and tougher meat, causing more fluid loss after cooking, compared to the normal quality group (P < 0.05). However, there were no significant differences in the quality traits between the WS groups (P > 0.05), except for lightness and cooking loss. Higher αß-crystallin and HSP90 expression levels were observed in PSE-like breast compared to normal quality breast (P < 0.05), whereas WS pattern was not related with HSPs levels (P > 0.05). Therefore, HSP levels at the early postmortem period, especially those of αß-crystallin and HSP90, were associated with the breast quality characteristics of PSE-like condition broilers.

Characterization of Collagen Structure in Normal, Wooden Breast and Spaghetti Meat Chicken Fillets by FTIR Microspectroscopy and Histology.

Recently, two chicken breast fillet abnormalities, termed Wooden Breast (WB) and Spaghetti Meat (SM), have become a challenge for the chicken meat industry. The two abnormalities share some overlapping morphological features, including myofiber necrosis, intramuscular fat deposition, and collagen fibrosis, but display very different textural properties. WB has a hard, rigid surface, while the SM has a soft and stringy surface. Connective tissue is affected in both WB and SM, and accordingly, this study's objective was to investigate the major component of connective tissue, collagen. The collagen structure was compared with normal (NO) fillets using histological methods and Fourier transform infrared (FTIR) microspectroscopy and imaging. The histology analysis demonstrated an increase in the amount of connective tissue in the chicken abnormalities, particularly in the perimysium. The WB displayed a mixture of thin and thick collagen fibers, whereas the collagen fibers in SM were thinner, fewer, and shorter. For both, the collagen fibers were oriented in multiple directions. The FTIR data showed that WB contained more ß-sheets than the NO and the SM fillets, whereas SM fillets expressed the lowest mature collagen fibers. This insight into the molecular changes can help to explain the underlying causes of the abnormalities.

Effects of Dipping Chicken Breast Meat Inoculated with Listeria monocytogenes in Lyophilized Scallion, Garlic, and Kiwi Extracts on Its Physicochemical Quality.

This study was conducted to evaluate the antioxidant and antimicrobial activities of lyophilized extracts of scallions (Allium fistulosum L., SLE), garlic (Allium sativum, GLE), and gold kiwi (Actinidia chinensis, GKE) and their effects on the quality of chicken breast meat inoculated with L. monocytogenes during storage for 9 days at 4°C. The lowest minimum inhibitory concentration and minimum bactericidal concentration (25 and 100 mg/mL, respectively) against L. monocytogenes were observed for SLE and GLE, respectively. GKE had the lowest half-maximal inhibitory concentration (IC50) for 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activity (5.06 mg/mL). The pH values of meat inoculated with L. monocytogenes and dipped in 1% SLE (LSLE), 1% GLE (LGLE), or 1% GKE (LGKE) were lower than that of the control on day 3 of storage (p<0.05). The initial population of L. monocytogenes in meat was 4.95-5.01 Log CFU/g. However, the population in the LSLE (5.73 Log CFU/g) was lower than that in the control (6.23 Log CFU/g) on day 5 (p<0.05). The volatile basic nitrogen value of the LSLE (19.90 mg/100 g) was lower than that of the control (24.38 mg/100 g) on day 7 (p<0.05). Moreover, treatment with SLE resulted in the maintenance of meat quality and reduced the population of L. monocytogenes on the meat. Thus, SLE may be used as an alternative natural and environmentally friendly sanitizer for reducing L. monocytogenes contamination in the chicken meat industry.

Effect of acute heat stress and slaughter processing on poultry meat quality and postmortem carbohydrate metabolism.

This study investigated the effects of acute heat stress and slaughter processing on poultry meat quality and carbohydrate metabolism. Broilers (200) were randomly divided into 2 groups receiving heat stress (HS; 36°C for one h), compared to a non-stressed control (C). At slaughter, each group was further divided into 2 groups for slaughter processing (L = laboratory; F = commercial factory). L group breasts were removed immediately after bleeding without carcass scalding or defeathering, and stored at 4°C. F group broilers were scalded (60°C, 45 s) after bleeding and defeathering. Then the breasts were removed and cooled in ice water until the core temperature was ≤4°C. Rates of Pectoralis core temperature and pH decline were changed by slaughter processing, but only HS affected ultimate pH in group L. HS muscles had higher L* values (P < 0.05) than controls at 24 h postmortem. Laboratory processing "hot-deboning" increased drip loss, which resulted in a lower cooked loss (P < 0.05). Postmortem glycolysis was affected only by HS. The speed of lactic acid accumulation and glycogen degradation was faster in the HS group than controls at 5 min postmortem. During storage the glycolysis rates were not different (P > 0.05). Sarcoplasmic protein solubility was higher in F processed birds (P < 0.05). HS decreased the solubility of myofibrillar and total protein in the L-slaughtered birds. Thus, HS caused a higher frequency of accelerated muscle glycolysis than controls. Factory processing (chilling) could not completely eliminate the effects of accelerated glycolysis caused by pre-slaughter HS.