New alternatives for improving and assessing the color of dark–cutting beef – a review

Myoglobin (Mb) is a sarcoplasmic heme protein present in muscle cells, which acts as a short–term oxygen (O2) reserve in the muscle tissue. After slaughtering and exsanguination, Mb is the major pigment that provides the red color in meat. The concentration of Mb together with its redox state are two pivotal factors that determine meat color. The elevated pH of dark–cutting beef can affect both physical and biochemical properties resulting in decreased oxygenation. The darkening observed in high ultimate pH (pHu) beef concerns meat processors as color is the initial attribute that impacts on the purchase. Thus, any atypical meat color (i.e., loss of brightness) reduces consumer interest in the product. Several studies have demonstrated that immunological castration is effective in preventing both aggressive behavior and undesirable dark–cutting of bull meat. However, little information is available on the effects of processing techniques that limit the oxidation of ferrous iron (Fe2+), Mb or promote metmyoglobin (MMb) reduction in dark–cutting beef. Because of the importance of color to fresh beef marketability, this review aimed at overviewing the significance of pHu in beef color and color stability and to discuss new alternatives for improving and assessing the beef color of dark–cutting beef, especially in Nellore bulls and their crossbreds, which are widely used in beef cattle production in Brazil.

New alternatives for improving and assessing the color of dark­cutting beef ­ a review

Myoglobin (Mb) is a sarcoplasmic heme protein present in muscle cells, which acts as a short­term oxygen (O2) reserve in the muscle tissue. After slaughtering and exsanguination, Mb is the major pigment that provides the red color in meat. The concentration of Mb together with its redox state are two pivotal factors that determine meat color. The elevated pH of dark­cutting beef can affect both physical and biochemical properties resulting in decreased oxygenation. The darkening observed in high ultimate pH (pHu) beef concerns meat processors as color is the initial attribute that impacts on the purchase. Thus, any atypical meat color (i.e., loss of brightness) reduces consumer interest in the product. Several studies have demonstrated that immunological castration is effective in preventing both aggressive behavior and undesirable dark­cutting of bull meat. However, little information is available on the effects of processing techniques that limit the oxidation of ferrous iron (Fe2+), Mb or promote metmyoglobin (MMb) reduction in dark­cutting beef. Because of the importance of color to fresh beef marketability, this review aimed at overviewing the significance of pHu in beef color and color stability and to discuss new alternatives for improving and assessing the beef color of dark­cutting beef, especially in Nellore bulls and their crossbreds, which are widely used in beef cattle production in Brazil.(AU)

New alternatives for improving and assessing the color of darkcutting beef a review

ABSTRACT Myoglobin (Mb) is a sarcoplasmic heme protein present in muscle cells, which acts as a shortterm oxygen (O2) reserve in the muscle tissue. After slaughtering and exsanguination, Mb is the major pigment that provides the red color in meat. The concentration of Mb together with its redox state are two pivotal factors that determine meat color. The elevated pH of darkcutting beef can affect both physical and biochemical properties resulting in decreased oxygenation. The darkening observed in high ultimate pH (pHu) beef concerns meat processors as color is the initial attribute that impacts on the purchase. Thus, any atypical meat color (i.e., loss of brightness) reduces consumer interest in the product. Several studies have demonstrated that immunological castration is effective in preventing both aggressive behavior and undesirable darkcutting of bull meat. However, little information is available on the effects of processing techniques that limit the oxidation of ferrous iron (Fe2+), Mb or promote metmyoglobin (MMb) reduction in darkcutting beef. Because of the importance of color to fresh beef marketability, this review aimed at overviewing the significance of pHu in beef color and color stability and to discuss new alternatives for improving and assessing the beef color of darkcutting beef, especially in Nellore bulls and their crossbreds, which are widely used in beef cattle production in Brazil.

Utilização da enzima transglutaminase em medalhões de aparas e CMS de espinhaço de tilápia / Utilization of transglutaminase in medallions from parings and minced fish of spine of tilapia

The use of by-products generated in the filleting of fish constitutes a promising alternative for developing new products. The aim of this study was develop the product "tilapia medallion" using parings and minced fish of spine of tilapia associated with the enzyme transglutaminase, analyzing instrumentally the texture and identify the best formulation evaluated sensorially. Were tested formulations containing different percentages of parings and minced fish of spine of tilapia, and preliminary sensory tests selected two of the four initial formulations, the products B (40% parings + 60% minced fish) and C (60% parings + 40% minced fish). The products B e C were subjected to physico-chemical, microbiological and sensory analysis. The products presented high levels of fat and ash, because the parings from the ventral parts of the fish are rich in fat and additives used in formulations, respectively.The C product had more tender texture that the product B, probably due to the higher concentration of parings from the ventral parts used in its formulation. The sensory analysis to acceptance not detected significant difference between the formulations.(AU)

O aproveitamento de subprodutos gerados na filetagem de pescado constitui-se uma alternativa promissora para elaboração de novos produtos. O objetivo deste estudo foi desenvolver o produto medalhão de tilápia utilizando como matéria-prima aparas e carne mecanicamente separada (CMS) de espinhaço de tilápia, associado à enzima transglutaminase, analisar a textura instrumentalmente e identificar a formulação melhor avaliada sensorialmente, quanto à aceitação. Foram avaliadas formulações contendo diferentes porcentagens de aparas e CMS de espinhaço de tilápia, e testes sensoriais preliminares selecionaram duas das quatro formulações iniciais, denominadas produtos B (40% de aparas + 60% de CMS) e C (60% de aparas + 40% de CMS). Os medalhões B e C foram submetidos à análises físico-química, microbiológica e sensorial. Os produtos apresentaram elevado teor de lipídios e cinzas, em função das aparas provenientes das partes ventrais do pescado, ricas em gordura, e dos aditivos utilizados nas formulações, respectivamente. O produto C apresentou textura mais tenra que o produto B, provavelmente em função da maior concentração de aparas ventrais utilizadas na sua formulação. A análise sensorial não detectou diferença significativa entre as formulações quanto à aceitação.(AU)

Utilização da enzima transglutaminase em medalhões de aparas e CMS de espinhaço de tilápia / Utilization of transglutaminase in medallions from parings and minced fish of spine of tilapia

The use of by-products generated in the filleting of fish constitutes a promising alternative for developing new products. The aim of this study was develop the product "tilapia medallion" using parings and minced fish of spine of tilapia associated with the enzyme transglutaminase, analyzing instrumentally the texture and identify the best formulation evaluated sensorially. Were tested formulations containing different percentages of parings and minced fish of spine of tilapia, and preliminary sensory tests selected two of the four initial formulations, the products B (40% parings + 60% minced fish) and C (60% parings + 40% minced fish). The products B e C were subjected to physico-chemical, microbiological and sensory analysis. The products presented high levels of fat and ash, because the parings from the ventral parts of the fish are rich in fat and additives used in formulations, respectively.The C product had more tender texture that the product B, probably due to the higher concentration of parings from the ventral parts used in its formulation. The sensory analysis to acceptance not detected significant difference between the formulations.

O aproveitamento de subprodutos gerados na filetagem de pescado constitui-se uma alternativa promissora para elaboração de novos produtos. O objetivo deste estudo foi desenvolver o produto medalhão de tilápia utilizando como matéria-prima aparas e carne mecanicamente separada (CMS) de espinhaço de tilápia, associado à enzima transglutaminase, analisar a textura instrumentalmente e identificar a formulação melhor avaliada sensorialmente, quanto à aceitação. Foram avaliadas formulações contendo diferentes porcentagens de aparas e CMS de espinhaço de tilápia, e testes sensoriais preliminares selecionaram duas das quatro formulações iniciais, denominadas produtos B (40% de aparas + 60% de CMS) e C (60% de aparas + 40% de CMS). Os medalhões B e C foram submetidos à análises físico-química, microbiológica e sensorial. Os produtos apresentaram elevado teor de lipídios e cinzas, em função das aparas provenientes das partes ventrais do pescado, ricas em gordura, e dos aditivos utilizados nas formulações, respectivamente. O produto C apresentou textura mais tenra que o produto B, provavelmente em função da maior concentração de aparas ventrais utilizadas na sua formulação. A análise sensorial não detectou diferença significativa entre as formulações quanto à aceitação.