Massami Shimokomaki

Parameters determining the quality of charqui, an intermediate moisture meat product

Charqui is a typical Brazilian meat product obtained by salting and sun-drying beef samples. The chemical, physical and microbiological characteristics of the charqui were evaluated throughout processing and storage. The results confirm charqui is an intermediate moisture meat product (A(w) = 0·70-0·75). A close relationship between moisture, pretein and ash vaiues was found, suggesting the possibility of using the resulting charqui A(w) value as a parameter to define the product instead of the official moisture and mineral residue contents. The TBA determination, which expresses the state of lipid oxidation, rapidly reached the maximum value, corroborating the previous observations on the salt pro-oxidant role, and then decreased gradually. A gradual decrease in microorganism count during processing and storage of charqui was also observed. These results indicate the feasibility of obtaining a final product with a low level of microbial count when raw materials of good quality, and adequate handling conditions, are used for charqui production.

Hamburger meat identification by dot-ELISA

The use of low cost meats to adulterate meats and meat products has been reported. Appropriate methods of analysis then are needed in order to detect this practice. The dot-ELISA method was used to identify the meat of different animal species and to detect adulteration of hamburgers. Antisera to bovine, chicken, swine and horse albumin were produced and they could detect the meat extract of the homologous species at concentrations as low as 0.6%. Thus, the anti-albumin antisera could identify bovine, chicken, swine and horse meat with adequate specificity and sensitivity both in isolation and when added to hamburger. Commercial samples of bovine, chicken and swine hamburgers showed no adulteration with bovine, chicken, swine or horse meats. Our expectation of hamburger adulteration was not confirmed.

Charqui meats are hurdle technology meat products

Abstract Charqui meat is a tropical intermediate meat product formulated using hurdle technology, a concept described by Leistner (1,2). Salt, sodium nitrite, dehydration, and packaging are hurdles sequentially applied to inhibit deteriorating microorganisms with the possibility of selecting desirable microbiota. This would characterize charqui and its derivatives as fermented meat products. This paper reviews biochemical, physico‐chemical, and ultrastructural changes that occur during processing of charquis.

Charqui meats as fermented meat products: role of bacteria for some sensorial properties development

Jerked beef, a derivative of charqui meat, is a cured, salted and dried meat product. The presence of halotolerant bacteria, where Staphylococcus spp. (84.2%) were the predominant species, would act eventually as starter cultures and was followed throughout processing. Jerked beef prepared separately with exogenous S. carnosus and S. xylosus as starter cultures resulted in high proteolysis. Samples prepared with S. xylosus had the highest proteolysis and were preferred by the sensory panel. This research has suggested that jerked beef (and thus charqui meat) prepared under these conditions is a fermented meat product.

An ultrastructural observation on charquis, salted and intermediate moisture meat products

Charqui meats are tropical intermediate moisture meat products containing 45% moisture and 15% salt with an A(w) of 0.70-0.75. Light microscopic studies of a charqui derivative popularly known as Jerked beef (JB) demonstrated considerable shrinking of muscle cells and the formation of fluid channels. The area occupied by muscle cells in JB was diminished by 30-40% in comparison with control samples. At the ultrastructural level, A-bands including the M-line disappeared indicating proteins were lost during processing. Z-lines appeared to be fragmented. In the enlarged extracellular spaces, collagen fibers retained their banding patterns although an empty space was observed surrounding these fibers. The denaturation of myofibrillar proteins during processing and the osmotic pressure caused by salting create conditions for water movement from the myofibrillar compartments to the intermyofibrillar space, then to the extracellular matrix and ultimately to the meat surface.

Intermediate moisture meat product: biological evaluation of charqui meat protein quality

Abstract Charqui is a typical salted and dry Brazilian meat product. A harsh condition for salting and drying during charqui processing could eventually damage its biological value. Therefore protein quality of raw and cooked charqui meat flours was chemically and biologically evaluated by rat growth and nitrogen balance studies. Proximate chemical compositions of desalted raw and cooked charqui flour samples showed protein content of 74.2 and 81.1%, respectively and lipid contents of 20.06 and 13.52%, respectively. There was a good balance of essential amino acids in both samples. Feeding of flour diets prepared from exhaustively desalted and dried cooked and raw charqui samples resulted in high protein efficiency ratios, in high net protein utilisations and high nitrogen balances thus showing a high biological value and also high true digestibility, with NPU similar to casein.

Lipid oxidation and fatty acid profile related to broiler breast meat color abnormalities

The aim of this work was to study the influence of lipid oxidation on broiler breast meat (Pectoralis major m) color abnormalities. There were 27.0 % more lipid oxidation in PSE in relation to normal meat and 41.0 % more in relation to DFD-like meat (p<0.05). The fatty acid profile was also significantly different since the arachidonic acid (AA) fraction increased 38.6 and 70.5 % in PSE meat comparing to normal and DFD-like meats, respectively. The ratio PUFA/SFA changed in these three types of meat: 0.736, 0.713 and 0.694 for PSE, normal and DFD-like meat respectively, reflecting the highest production of polyunsaturated fatty acids in the PSE meat samples. Results indicated that phospholipase A2 enzyme activities played a relevant role towards the development of PSE-meat syndrome in a cascade of biochemical reactions promoting the formation of free radicals from AA, which ultimately damaged the muscle membrane systems.

Synergism between dietary vitamin E and exogenous phytic acid in prevention of warmed-over flavour development in chicken breast meat, Pectoralis major M.

O efeito da suplementacao de acetato a-tocoferol (AT) e a aplicacao exogena desta vitamina E associada com acido fitico (AP) foi avaliado no desenvolvimento do WOF em file de peito de frango. O grupo controle foi alimentado com 7,7IU de AT/kg de racao e o grupo suplementado foi alimentado com 200IU de AT/kg de racao. A vitamina E na dieta inibiu o desenvolvimento de WOF, medido atraves do TBARS, em 78,9; 69,0; 60,7 e 46,5% (p<0,05) durante armazenamento a 6oC durante 0, 1,3 e 5 dias respectivamente. Esta inibicao foi significativamente aumentada (p<0,05) em 86,1; 91,6; 92,9 e 95,3% armazenamento a 6oC durante 0, 1,3 e 5 dias respectivamente, quando 2mM de PA foi adicionado no file de peito de frango suplementado. Atraves da Metodologia de Superficie de Resposta, no experimento exogeno, foi observado que o AT parece nao ter um papel significante em relacao a inibicao da oxidacao, enquanto que AP inibe parcialmente nas amostras armazenadas a 6oC durante 48h. Esses resultados mostram que AT na dieta inibiria na iniciacao e subsequentemente AP atuaria na propagacao, ocorrendo uma reacao sinergica entre os dois antioxidantes.

Chemical basis for beef charqui meat texture

This work evaluated the relationship of charqui meat (CHM) chemical composition with the tenderness throughout its production. CHM was prepared from beef Vastus lateralis of 4-5 years old. Shear force of fresh CHM showed an approx. 3-fold increase in toughness compared to the raw material while, in the case of cooked CHM it was 6-fold increased in relation to the raw charqui. The moisture content decreased by 39.0 and 58.0% (p<0.05) for uncooked and cooked CHM, respectively, in relation to the raw material. Mathematical modeling of the influence of these meat components showed that shear force increased exponentially with the loss of moisture. The texture of CHM was the result of a multitude of factors involving myofibril proteins which promoted dynamic biochemical events such as the binding of water molecules. It was the amount of the latter which ultimately determine the final charqui meat texture.

Underlying connections between the redox system imbalance, protein oxidation and impaired quality traits in pale, soft and exudative (PSE) poultry meat.

The connections between the redox imbalance in post-mortem muscle, early protein oxidation and the onset of pale, soft and exudative (PSE) condition in chicken breast are studied. PSE was induced by incubation of post-mortem chicken carcasses at 37°C for 200min. PSE-induced muscle consistently had faster pH decline and lower pH at 200min (5.84 vs. 6.59) and 24h (5.69 vs. 5.96), higher L(∗) (54.4 vs. 57.3), and lower texture and water holding capacity (WHC) than normal meat. The activities of catalase, glutathione peroxidase and superoxide dismutase were significantly lower in PSE-induced samples than in the normal counterparts. PSE was more susceptible to proteolysis and protein oxidation than normal meat during succeeding chilled storage with more intense tryptophan and thiols depletion, higher protein carbonylation and more intense formation of protein cross-links. We provide plausible explanations to support the role of protein oxidation in the impaired quality PSE chicken.