Sensory acceptability of raw and extruded bovine rumen protein in processed meat products

The use of bovine rumen protein (raw and extruded) as a replacement for extruded soy protein concentrate in three meat products (pork sausage, chicken hamburger, and kibbe) was investigated. Similarity between rumen and soy protein meat products was assessed using triangle tests and sensory acceptability evaluated by consumer panelists using a nine-point hedonic scale. The addition of raw rumen protein was detected in all meat product types tested, while extruded rumen protein was only detected in kibbe. The addition of raw rumen protein decreased the acceptability of pork sausage aroma and flavor, but improved kibbe appearance, texture and overall acceptability. The addition of extruded rumen protein reduced the acceptability of chicken hamburger texture, but improved pork sausage flavor. Replacement of soy protein by bovine rumen protein is feasible based upon sensory results, but depended upon its form and the type of meat product to which it was added. (C) 2011 Elsevier Ltd. All rights reserved.

Adding Value to the Meat of Spent Laying Hens Manufacturing Sausages with a Healthy Appeal

The aim of this study was to evaluate the viability of the use of spent laying hens` meat in the manufacturing of mortadella-type sausages with healthy appeal by using vegetable oil instead of animal fat. 120 Hy-line (R) layer hens were distributed in a completely randomized design into two treatments of six replicates with ten birds each. The treatments were birds from light Hy-line (R) W36 and semi-heavy Hy-line (R) Brown lines. Cold carcass, wing, breast and leg fillets yields were determined. Dry matter, protein, and lipid contents were determined in breast and leg fillets. The breast and legg fillets of three replicates per treatment were used to manufacture mortadella. After processing, sausages were evaluated for proximal composition, objective color, microbiological parameters, fatty acid profile and sensory acceptance. The meat of light and semi-heavy spent hens presented good yield and composition, allowing it to be used as raw material for the manufacture of processed products. Mortadellas were safe from microbiological point of view, and those made with semi-heavy hens fillets were redder and better accepted by consumers. Values for all sensory attributes were evaluated over score 5 (neither liked nor disliked). Both products presented high polyunsaturated fatty acid contents and good polyunsaturated to saturated fatty acid ratio. The excellent potential for the use of meat from spent layer hens of both varieties in the manufacturing of healthier mortadella-type sausage was demonstrated.

Effects of the season of the year, truck type and location on truck on skin bruises and meat quality in pigs

The purpose of this study was to evaluate the effect of the season of the year (summer vs winter), type of truck (A: single decker vs B : double-decker) and pig location on the truck (front, middle, rear) on the incidence of skin bruising and pork quality variation. For this purpose, 2660 gilts of an average weight of 126.7 (+/- 6.6) kg originating from 19 different farms were used. No interaction between season of the year, type of truck and location on truck was observed. A higher number of bruises on the body at unloading and slaughter (P < 0.0001) and a higher number of bruises on the carcass (P < 0.01) were observed in winter. At unloading a higher number of bruises on the body and on the carcass after slaughter was observed in pigs transported on Truck A (P=0.004 and P=0.05). A higher, although not significant, number of bruises was found on the body of pigs transported in the rear compartment of both trucks. Higher paleness value was found in the longissimus and semimembranosus muscles in summer (P=0.0001) than in winter. Cold and heat stress have a negative influence on skin bruises and meat quality, respectively. Poor vehicle design increases the incidence of bruised carcasses without detracting from pork quality regardless of the climate conditions tested and location of the animal it] the truck. (c) 2006 Elsevier B.V. All rights reserved.

Qualitative-feed-restricted heavy swine: meat quality and morpho-histochemical characteristics of muscle fibers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Sensory acceptability of raw and extruded bovine rumen protein in processed meat products

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comparative analysis of different meat traceability systems using multiple criteria and a social network approach

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dietary fiber as fat substitute in emulsified and cooked meat model system

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of the starting time of preslaughter feed withdrawal on welfare of pigs and pork quality

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparison of methodologies for assessment of pork loin eye area

The determination of loin eye area (LEA) is one of the most common methods to assess carcass quality and it is possible to adjust calculations to predict meat amount in the carcass which is one of the important features in the classification process. The aim of this study was to compare different methodologies used to determine LEA in swine. Fifteen crossbred pigs, Landrace x Large White, males and females, were slaughtered at 140 days of age. After 24 hours of cooling at 4°C, the Longissimus dorsi muscle was removed from the left half part of carcasses for evaluation of LEA between the 12th and 13th rib. The methods were: point counting on plastic grid of 1 cm2 and 0.25 cm2 (PCGP 1 cm2 and PCGC 0.25 cm2 ), circumference method by Echo Image Viewer (ECHO), circumference method using AutoCad ® program (CAD) and method of weighing paper (WP). The design was completely randomized with 15 replications per treatment and the data were subjected to Pearson correlation and variance analysis. Averages were compared by Tukey test at a significance level of 5%. LEA values were: 35.84, 35.69, 33.86, 34.22 and 36.71 cm2 , for the PCGP 1 cm2 , PCGP 0.25 cm2 , ECHO, CAD and WP methods, respectively. The LEA values determined by methods PCGP 1 cm2 , PCGP 0.25 cm2 and WP were similar; however they were higher than those obtained by the ECHO and CAD methodologies (P<0.0001). PCGP 1 cm2 , PCGP 0.25 cm2 and WP methods may overestimate LEA values. The choice of method to be used should be based on its practicality and availability of resources, since the difference obtained between them is low.

Characterization of atypical Listeria innocua isolated from swine slaughterhouses and meat markets

Atypical Listeria innocua strains presenting phenotypic characteristics similar to those of Listeria monocyto genes were recently isolated from food and the environment. These isolates also tested positive for virulence genes specific to L. monocytogenes. Here we report the isolation of atypical hemolytic L. innocua strains from the environment of pork processing plants in Brazil. The strains were positive for L. monocytogenes virulence genes hly, inlA and inlB by PCR and presented genotypic similarities with human isolates of L. monocytogenes via the AFLP technique using HindIII single enzyme protocol. Phenotypic and genotypic similarities suggest that these atypical L. innocua may be pathogenic strains. (C) 2012 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Effect of natural antioxidant combinations on lipid oxidation in cooked chicken meat during refrigerated storage

The effect of combinations of sage, oregano and honey on lipid oxidation in cooked chicken meat during refrigeration at 4 degrees C for 96 h was determined. Chicken samples (thigh and breast) were then separated into five groups; control; butylated hydroxytoluene; oregano + sage; oregano + sage + 5%honey and oregano + sage + 10%honey. Quantitative measurements of thiobarbituric acid reactive substances, conjugated dienes, hexanal, fatty acids, cholesterol and cholesterol oxides were used as indicators of lipid oxidation. Acceptability and preference were also evaluated. The effectiveness of the natural antioxidants for reducing the velocity of lipid oxidation in cooked chicken thigh and breast was demonstrated after 48 and 96 h of refrigeration at 4 degrees C. The treatments that presented the lowest hexanal values after 96 h of refrigeration were oregano + sage + 5%honey and oregano + sage + 10%honey. Only traces of free cholesterol oxides were found (25-OH, 7-k, 7 alpha-OH and 7 beta-OH). The natural antioxidants protected cooked chicken meat from oxidation processes and resulted in great acceptability. (C) 2012 Elsevier Ltd. All rights reserved.

Evaluation of the Concentration of Nonessential and Essential Elements in Chicken, Pork, and Beef Samples Produced in Brazil

Food safety is a global concern. Meat represents the most important protein source for humans. Thus, contamination of meat products by nonessential elements is a ready source of human exposure. In addition, knowledge of the concentration of essential elements is also relevant with respect to human nutrition. The aim of the present study was to determine the concentration of 17 elements in pork, beef, and chicken produced in Brazil. Meat samples were analyzed by inductively coupled plasma mass spectrometry. The estimated daily intake for nonessential elements including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), and antimony (Sb) through meat consumption is below the toxicological reference values. However, high levels were detected for the nonessential element cesium (Cs), mainly in beef samples, an observation that deserves future studies to identify the source of contamination and potential adverse consequences.

Different approaches to identify markers for meat quality and production traits in pigs: analysis of the transcriptome in post mortem skeletal muscle and investigation of candidate genes

Due to the growing attention of consumers towards their food, improvement of quality of animal products has become one of the main focus of research. To this aim, the application of modern molecular genetics approaches has been proved extremely useful and effective. This innovative drive includes all livestock species productions, including pork. The Italian pig breeding industry is unique because needs heavy pigs slaughtered at about 160 kg for the production of high quality processed products. For this reason, it requires precise meat quality and carcass characteristics. Two aspects have been considered in this thesis: the application of the transcriptome analysis in post mortem pig muscles as a possible method to evaluate meat quality parameters related to the pre mortem status of the animals, including health, nutrition, welfare, and with potential applications for product traceability (chapters 3 and 4); the study of candidate genes for obesity related traits in order to identify markers associated with fatness in pigs that could be applied to improve carcass quality (chapters 5, 6, and 7). Chapter three addresses the first issue from a methodological point of view. When we considered this issue, it was not obvious that post mortem skeletal muscle could be useful for transcriptomic analysis. Therefore we demonstrated that the quality of RNA extracted from skeletal muscle of pigs sampled at different post mortem intervals (20 minutes, 2 hours, 6 hours, and 24 hours) is good for downstream applications. Degradation occurred starting from 48 h post mortem even if at this time it is still possible to use some RNA products. In the fourth chapter, in order to demonstrate the potential use of RNA obtained up to 24 hours post mortem, we present the results of RNA analysis with the Affymetrix microarray platform that made it possible to assess the level of expression of more of 24000 mRNAs. We did not identify any significant differences between the different post mortem times suggesting that this technique could be applied to retrieve information coming from the transcriptome of skeletal muscle samples not collected just after slaughtering. This study represents the first contribution of this kind applied to pork. In the fifth chapter, we investigated as candidate for fat deposition the TBC1D1 [TBC1 (tre-2/USP6, BUB2, cdc16) gene. This gene is involved in mechanisms regulating energy homeostasis in skeletal muscle and is associated with predisposition to obesity in humans. By resequencing a fragment of the TBC1D1 gene we identified three synonymous mutations localized in exon 2 (g.40A>G, g.151C>T, and g.172T>C) and 2 polymorphisms localized in intron 2 (g.219G>A and g.252G>A). One of these polymorphisms (g.219G>A) was genotyped by high resolution melting (HRM) analysis and PCR-RFLP. Moreover, this gene sequence was mapped by radiation hybrid analysis on porcine chromosome 8. The association study was conducted in 756 performance tested pigs of Italian Large White and Italian Duroc breeds. Significant results were obtained for lean meat content, back fat thickness, visible intermuscular fat and ham weight. In chapter six, a second candidate gene (tribbles homolog 3, TRIB3) is analyzed in a study of association with carcass and meat quality traits. The TRIB3 gene is involved in energy metabolism of skeletal muscle and plays a role as suppressor of adipocyte differentiation. We identified two polymorphisms in the first coding exon of the porcine TRIB3 gene, one is a synonymous SNP (c.132T> C), a second is a missense mutation (c.146C> T, p.P49L). The two polymorphisms appear to be in complete linkage disequilibrium between and within breeds. The in silico analysis of the p.P49L substitution suggests that it might have a functional effect. The association study in about 650 pigs indicates that this marker is associated with back fat thickness in Italian Large White and Italian Duroc breeds in two different experimental designs. This polymorphisms is also associated with lactate content of muscle semimembranosus in Italian Large White pigs. Expression analysis indicated that this gene is transcribed in skeletal muscle and adipose tissue as well as in other tissues. In the seventh chapter, we reported the genotyping results for of 677 SNPs in extreme divergent groups of pigs chosen according to the extreme estimated breeding values for back fat thickness. SNPs were identified by resequencing, literature mining and in silico database mining. analysis, data reported in the literature of 60 candidates genes for obesity. Genotyping was carried out using the GoldenGate (Illumina) platform. Of the analyzed SNPs more that 300 were polymorphic in the genotyped population and had minor allele frequency (MAF) >0.05. Of these SNPs, 65 were associated (P<0.10) with back fat thickness. One of the most significant gene marker was the same TBC1D1 SNPs reported in chapter 5, confirming the role of this gene in fat deposition in pig. These results could be important to better define the pig as a model for human obesity other than for marker assisted selection to improve carcass characteristics.

Candidate genes affecting fat deposition, carcass composition and meat quality traits in pigs

Pig meat quality is determined by several parameters, such as lipid content, tenderness, water-holding capacity, pH, color and flavor, that affect consumers’ acceptance and technological properties of meat. Carcass quality parameters are important for the production of fresh and dry-cure high-quality products, in particular the fat deposition and the lean cut yield. The identification of genes and markers associated with meat and carcass quality traits is of prime interest, for the possibility of improving the traits by marker-assisted selection (MAS) schemes. Therefore, the aim of this thesis was to investigate seven candidate genes for meat and carcass quality traits in pigs. In particular, we focused on genes belonging to the family of the lipid droplet coat proteins perilipins (PLIN1 and PLIN2) and to the calpain/calpastatin system (CAST, CAPN1, CAPN3, CAPNS1) and on the gene encoding for PPARg-coactivator 1A (PPARGC1A). In general, the candidate genes investigation included the protein localization, the detection of polymorphisms, the association analysis with meat and carcass traits and the analysis of the expression level, in order to assess the involvement of the gene in pork quality. Some of the analyzed genes showed effects on various pork traits that are subject to selection in genetic improvement programs, suggesting a possible involvement of the genes in controlling the traits variability. In particular, significant association results have been obtained for PLIN2, CAST and PPARGC1A genes, that are worthwhile of further validation. The obtained results contribute to a better understanding of biological mechanisms important for pig production as well as for a possible use of pig as animal model for studies regarding obesity in humans.

The impact of swine welfare on some qualitative traits of meat and long cured animal derived products

The present dissertation collects the results of three different research trials which have the common aim to understand the effects of swine welfare (both at farm level and during transport) on the main fresh and dry-cured meat characteristics. The first trial was carried out in order to compare the effects of illumination regimes differing in light duration or light intensity on meat and ham quality of Italian heavy pigs. The results of this trial support the conclusion that, within a moderate range of light intensity and given an appropriate dark period for animal rest, an increase of light duration or intensity above the minimum mandatory levels has no negative impact on carcass composition, meat or long-cured hams quality. The second trial was designed with the aim to investigate the effects of water restriction on growth traits, animal welfare and meat and ham quality of liquid-fed heavy pigs. Overall, the parameters analyzed as concerns growth rate, behavioural traits, blood, as well as carcass, fresh meat and cured hams quality were not affected by the absence of fresh drinking water. However, since liquid feeding did not suppress drinker use or drinker manipulation in the experimental groups, water restriction does not appear to be an applicable method to obtain a reduction of water waste. The third trial, which was carried out in Canada, tested the effectiveness of water sprinkling market-weight pigs (115±10Kg BW) before and after transport in reducing the heat stress experienced under commercial transport conditions. Our results show that the water sprinkling protocol proposed may reduce heat stress during transport and improve pork quality, particularly in specific trailer compartments. This body of research supports the general conclusion that swine welfare could be improved in different scenarios through simple and cost-effective means, without negatively affecting the quality of the main animal-derived products.