The effects of time and relative humidity on dry-aged beef: Traditional versus special bag.

The objective of this study was to evaluate the effects of relative humidity (RH) and different dry aging methods on the quality of beef. Sixteen loins, from eight carcasses, were used in this experiment. Each pair of loin was cut into eight sections with equal size, which were evenly assigned to eight treatments, by the combination of two dry aging methods (traditional and highly moisture-permeable special bag), two relative humidity (65 and 85% RH) and two aging times (21 and 42 days). At 85% RH, neither special bag nor the traditional dry aging methods were viable, since samples presented high microbiological counts, mucus and bad odor. At 65% RH, Enterobacteriaceae and lactic acid bacteria were not detected in any treatment. The highest aerobic plate count and psychrotrophic count were observed in the samples of the traditional dry-aged process whereas the special bag showed the greatest mold and yeast count. Regarding dry aging in special bag, there was a reduction in the weight loss (P < 0.05) and no change in the physical-chemical characteristics (P > 0.05) compared to traditional dry aging. The values of pH, moisture and Warner-Bratzler shear force were not affected (P > 0.05) by aging method and relative humidity. Thus, the results indicate that high RH should be avoided for both dry aging methods. Furthermore, the special bag dry aging can be considered an alternative to produce dry-aged beef, as it reduces weight losses even at conditions of lower relative humidity.

The Effects of Melatonin Supplementation on Sleep Quality and Assessment of the Serum Melatonin in ICU Patients: A Randomized Controlled Trial.

OBJECTIVES: To evaluate whether the use of exogenous melatonin affects sleep, reduces the prevalence of delirium, and decreases the need for analgosedation and to assess whether serum melatonin indices correlate with exogenous administration in critically ill patients. DESIGN: Double-blind, randomized, placebo-controlled study. SETTING: Multicenter ICUs of two tertiary hospitals. PATIENTS: A total of 203 adult patients who were admitted to the ICU and administered with analgesics and/or sedatives. INTERVENTIONS: Oral melatonin (10 mg) or placebo for up to seven consecutive nights. MEASUREMENTS AND MAIN RESULTS: The number of observed sleeping hours at night was assessed by the bedside nurse. Sleep quality was evaluated using the Richards Campbell Questionnaire Sleep (RCSQ). The prevalence of delirium, pain, anxiety, adverse reactions, duration of mechanical ventilation, length of ICU and hospital stays, and doses of sedative and analgesic drugs administered were recorded. The use of analgesics and sedatives was assessed daily. Melatonin levels were determined by enzyme-linked immunosorbent assay. Based on the RCSQ results, sleep quality was assessed to be better in the melatonin group than that in the placebo group with a mean (SD) of 69.7 (21.2) and 60.7 (26.3), respectively (p = 0.029). About 45.8% and 34.4% of participants in the melatonin and placebo groups had very good sleep (risk ratio, 1.33; 95% CI, 0.94-1.89), whereas 3.1% and 14.6% had very poor sleep (risk ratio, 0.21; 95% CI, 0.06-0.71), respectively. No significant difference was observed regarding the days free of analgesics or sedatives, the duration of night sleep, and the occurrence of delirium, pain, and anxiety. Melatonin serum peak levels at 2 AM were 150 pg/mL (range, 125-2,125 pg/mL) in the melatonin group and 32.5 pg/mL (range, 18.5-35 pg/mL) in the placebo group (p < 0.001). CONCLUSIONS: Melatonin was associated with better sleep quality, which suggests its possible role in the routine care of critically ill patients in the future.

Effects of freezing and thawing on microbiological and physical-chemical properties of dry-aged beef.

This study evaluated the effects of freezing, prior to and after dry aging, on the microbiological and physical-chemical quality of beef. Strip loins (n = 24) from 12 carcasses were assigned to four treatments: non-frozen dry aging (Dry); dry aging, steak fabrication, freezing and slow thawing (Dry + ST); freezing, fast thawing (FT; 20 °C/15 h) and dry aging (FT + Dry); freezing, slow thawing (ST; 4 °C/48 h) and dry aging (ST + Dry). Freezing conditions were - 20 °C/28 days and dry aging conditions were 2 °C/70% relative humidity, for 28 days. Freezing prior to dry aging did not affect the microbial counts compared to Dry. However, FT + Dry and ST + Dry increased (16%) total process loss (P < .05) compared to Dry and Dry+ST. Moreover, freezing changed volatile compounds profile. Thus, freezing prior to dry aging was not a feasible process due to increased process loss, while freezing after dry aging was considered a viable alternative to preserve the steaks without compromising beef physical-chemical traits.

Maturação seca e úmida da carne bovina e seus efeitos na qualidade sensorial e microbiológica

O perfil do consumidor brasileiro se tomou mais exigente em relação à qualidade da carne. Entre os atributos que fazem parte dessa definição, as características de palatabilidade são de suma importância para a avaliação de consumidor e podem ser melhoradas por meio da maturação. Essa técnica consiste em armazenar a carne em câmaras frias, sob condições controladas de temperatura, umidade relativa e velocidade do ar, por um período de tempo, a fim de que enzimas endógenas promovam mudanças em sua estrutura. Os métodos de maturação seca e úmida podem interferir diferentemente em muitos atributos. Em razão disso, esta revisão bibliográfica objetivou comparar esses dois processos, frente a alguns dos parâmetros de palatabilidade, como maciez, sabor e aroma da carne bovina, além da qualidade microbiológica dos produtos. Conclui-se que os processos de maturação, úmido e seco, melhoram a maciez da carne na mesma proporção, mas a maturação a seco possibilita o desenvolvimento de atributos de sabor mais desejáveis, quando comparado com a maturação úmida. Entretanto, os mecanismos responsáveis por esta melhoria ainda não são claros e precisam ser melhor investigados. De maneira geral a proliferação de micro-organismos é melhor controlada na maturação a seco, mas cuidados especiais devem ser tomados quando da etapa de toalete, remoção das superfícies ressecadas, para não haver contaminação cruzada.(AU)

The Brazilian consumer's profile has become more rigorous regarding to meat quality. Among the attributes that are part of definition of quality, palatability characteristics are the main concern for consumer evaluation and may be improved by aging. This technique consists in storing the meat in cold storage under controlled conditions of temperature, relative humidity and air flow during a period of time in order to promote changes in its structure by the activity of endogenous enzymes. The dry-aging and wet-aging differ in many attributes. Therefore, this review proposes to compare those two processes regarding to some of their palatability parameters such as tenderness, flavor and aroma in beef, in addition to verify the microbiological quality of the products. lt is concluded that the dry aging process is simple, but requires special care to meet desired sensory results and ensure microbiological safety.(AU)

Maturação seca e úmida da carne bovina e seus efeitos na qualidade sensorial e microbiológica

O perfil do consumidor brasileiro se tomou mais exigente em relação à qualidade da carne. Entre os atributos que fazem parte dessa definição, as características de palatabilidade são de suma importância para a avaliação de consumidor e podem ser melhoradas por meio da maturação. Essa técnica consiste em armazenar a carne em câmaras frias, sob condições controladas de temperatura, umidade relativa e velocidade do ar, por um período de tempo, a fim de que enzimas endógenas promovam mudanças em sua estrutura. Os métodos de maturação seca e úmida podem interferir diferentemente em muitos atributos. Em razão disso, esta revisão bibliográfica objetivou comparar esses dois processos, frente a alguns dos parâmetros de palatabilidade, como maciez, sabor e aroma da carne bovina, além da qualidade microbiológica dos produtos. Conclui-se que os processos de maturação, úmido e seco, melhoram a maciez da carne na mesma proporção, mas a maturação a seco possibilita o desenvolvimento de atributos de sabor mais desejáveis, quando comparado com a maturação úmida. Entretanto, os mecanismos responsáveis por esta melhoria ainda não são claros e precisam ser melhor investigados. De maneira geral a proliferação de micro-organismos é melhor controlada na maturação a seco, mas cuidados especiais devem ser tomados quando da etapa de toalete, remoção das superfícies ressecadas, para não haver contaminação cruzada.

The Brazilian consumer's profile has become more rigorous regarding to meat quality. Among the attributes that are part of definition of quality, palatability characteristics are the main concern for consumer evaluation and may be improved by aging. This technique consists in storing the meat in cold storage under controlled conditions of temperature, relative humidity and air flow during a period of time in order to promote changes in its structure by the activity of endogenous enzymes. The dry-aging and wet-aging differ in many attributes. Therefore, this review proposes to compare those two processes regarding to some of their palatability parameters such as tenderness, flavor and aroma in beef, in addition to verify the microbiological quality of the products. lt is concluded that the dry aging process is simple, but requires special care to meet desired sensory results and ensure microbiological safety.

Maturação seca e úmida da carne bovina e seus efeitos na qualidade sensorial e microbiológica

O perfil do consumidor brasileiro se tornou mais exigente em relação à qualidade da carne. Entre os atributos que fazem parte dessa definição, as características de palatabilidade são de suma importância para a avaliação do consumidor e podem ser melhoradas por meio da maturação. Essa técnica consiste em armazenar a carne em câmaras frias, sob condições controladas de temperatura, umidade relativa e velocidade do ar, por um período de tempo, a fim de que enzimas endógenas promovam mudanças em sua estrutura. Os métodos de maturação seca e úmida podem interferir diferentemente em muitos atributos. Em razão disso, esta revisão bibliográfica objetivou comparar esses dois processos, frente a alguns dos parâmetros de palatabilidade, como maciez, sabor e aroma da carne bovina, além da qualidade microbiológica dos produtos. Conclui-se que os processos de maturação, úmido e seco, melhoram a maciez da carne na mesma proporção, mas a maturação a seco possibilita o desenvolvimento de atributos de sabor mais desejáveis, quando comparado com a maturação úmida. Entretanto, os mecanismos responsáveis por esta melhoria ainda não são claros e precisam ser melhor investigados. De maneira geral a proliferação de micro-organismos é melhor controlada na maturação a seco, mas cuidados especiais devem ser tomados quando da etapa de toalete, remoção das superfícies ressecadas, para não haver contaminação cruzada

The Brazilian consumer's profile has become more rigorous regarding to meat quality. Among the attributes that are part of definition of quality, palatability characteristics are the main concern for consumer evaluation and may be improved by aging. This technique consists in storing the meat in cold storage under controlled conditions of temperature, relative humidity and air flow during a period of time in order to promote changes in its structure by the activity of endogenous enzymes. The dry-aging and wet-aging differ in many attributes. Therefore, this review proposes to compare those two processes regarding to some of their palatability parameters such as tenderness, flavor and aroma in beef, in addition to verify the microbiological quality of the products. It is concluded that the dry aging process is simple, but requires special care to meet desired sensory results and ensure microbiological safety