Foi avaliado o desenvolvimento de warmed-over flavor (WOF) em carne assada bovina através da análise sensorial descritiva utilizando-se os músculos longo dorsal, semitendinoso e supra-espinhoso de novilhos da raça Nelore. Houve uma pré-seleção para recrutamento dos provadores, de 45 indivíduos inscritos, 35 foram pré-selecionados, destes, 24 foram avaliados com testes de diferença (quatro testes triangulares) para determinar a habilidade em discriminar diferenças de WOF em amostras de carne assada. Após os testes, 13 indivíduos foram selecionados para determinar o Perfil Sensorial de cada amostra. Inicialmente, 70 termos foram propostos pela equipe sensorial para a análise descritiva quantitativa, mas foram eliminados os termos que não apresentaram relevância para o produto, que não contribuíram para a discriminação de WOF na carne assada e os que apresentaram dificuldade de ser detectados pelos provadores. Restaram ao final 18 termos, sendo todos utilizados nos três tipos de músculos analisados. A análise descritiva quantitativa pode ser realizada para a obtenção de resultados satisfatórios para a pesquisa de warmed-over flavor em carne assada em experimentos científicos e para o desenvolvimento de produtos.

We evaluated the warmed-over flavor development (WOF) in bovine roast-beef through adescriptive sensory analysis using the Longissimus dorsi, Semitendinosus and Supraspinatus muscles of Nellore steers. There was a preselection for recruitment of assessors. Forty-five individuals were registered, being 35 preselected, from these, 24 were evaluated by difference tests (triangular tests) to determine the ability to discriminate WOF's differences in roast-beef samples. After the tests, 13 individuals were selected to determine the sensory profile of each sample. Initially, the sensory team proposed 70 terms for the quantitative descriptive analysis, but terms that were not relevant for the product, or did not contribute for WOF's discrimination in roast-beef as well as the ones that were not easily differentiated by the selected assessors were eliminated. The remained 18 terms were used in the three kinds of analyzed muscles. We concluded that quantitative descriptive analysis can be accomplished to obtain satisfactory results for warmed-over flavor research in roast-beef in both scientific experiments and product development.

Escherichia coli O157:H7 has been incriminated in food poisoning outbreaks and sporadic cases of hemorrhagic colitis and hemolytic uremic syndrome in many countries. Considering the high susceptibility of Minas Frescal cheese to contamination by E. coli O157:H7, the aim of this study was to determine the occurrence of this pathogen through PCR (Polymerase Chain Reaction) and ELISA (VIDAS ECO O157®, bioMérieux, Lyon, France) test. Thirty cheese samples manufactured by artisan farmhouse producers were collected from open-air markets in Goiânia and thirty from industries under Federal Inspection located in Goiás State which trade their products in supermarkets in Goiânia. E. coli O157:H7 was detected in 6.67% samples collected in open air markets using ELISA, and 23,33% with PCR. The pathogen was not detected in samples from industries under Federal Inspection.

Antimicrobial active packaging delays or inhibits microorganism growth in packed products, and it can be used in a variety of food systems. The objective of the present research was to develop packaging incorporated with natural antimicrobial agents (active film). The effects of the active film on the spoilage, pathogenic microorganism counts, pH and color of the refrigerated chicken breast cuts were analyzed. Cellulose acetate-based active films incorporating two concentrations (20% and 50%, v/w) of rosemary (Rosmarinus officinalis L.) essential oil were manufactured and placed in contact with the chicken breast cuts for six days. An analysis of variance and mean comparison tests (Tukey's test, p<0.05) were performed on the results. The films that contained 20% essential oil and were intercalated with chicken breast samples did not demonstrate significant effects on the control of psychrotrophic or total coliform microorganisms during the storage period; however, the films incorporated with 50% essential oil demonstrated efficacy toward the control of coliforms during the storage of the samples (6 days, 2 ± 2ºC). The pH was related to the psychrotrophic microorganism count and was not influenced by the treatment. The color was not influenced by the time of storage or the treatment. The results demonstrate that active films incorporating 50% rosemary essential oil are effective at controlling certain microorganisms in chicken breast cuts.

The objective of the present study was to evaluate the occurrence of warmed-over flavour (WOF) in cooked tenderloin and the influence of alpha-tocopherol on its inhibition. A total of 24 animals were confined, 12 of which received 1200 mg/head/day of alpha-tocopherol acetate for 90 days. Longissimus dorsi muscle cuts (tenderloin) were obtained for sensory profile assessment by nine trained tasters. The tasters evaluated the taste of the meat based on four general and 18 specific attributes. The results of the evaluations were analysed with ANOVA, post-hoc tests of the means (Tukey tests), and principal component analysis (PCA). There was no significant difference in the WOF between the cuts of meat from the supplemented and non-supplemented animals. However, as the refrigeration period increased, there was a decrease in the intensity of the umami and sweet taste attributes and the flavour and aroma of the roast meat as well as an increase in the intensity of the oxidised vegetable oil flavour and the aromas of fish, hard-boiled egg, flaxseed oil, and oxidised vegetable oil. The samples that had been stored for one day were characterised by PCA as having sweet and umami tastes and the flavour and aroma of roast meat, whereas after three days, the samples were classified as having sour and bitter tastes, the flavour of chicken and nuts, and the aroma of fish. The typical sensory attributes desirable for roasted meat decreased in intensity during the three days of storage after cooking, whereas the intensity of unpleasant (oxidative) attributes for the consumer increased.

An experiment with 630 one-day-old chicks experimentally inoculated with Salmonella Typhimurium was performed to evaluate the effects of an organic acid blend (benzoic, fumaric and 2-hydroxi-4-methylltio-butanoic - HMTBa) on intestinal health and performance. The experimental challenge with Salmonella Typhimurium occurred in two different routes of administration: via crop on the first day after hatching, and via feed, offered from seven to 14 days of age. These groups were treated with organic acids in a 3 × 2 (agent versus acid) factorial arrangement. Chicks treated with organic acids had higher weight gain, mean live weight and better feed conversion at 14 days of age, and higher weight gain at 28 days of age. Chicks treated with organic acids inoculated via crop had higher duodenum villi height than animals of the control group. Jejunum villi were higher in chicks of the negative control group compared with birds supplemented with organic acids. Small intestine pH in chicks of the inoculated group was lower compared with control group throughout the trial period. HMTBa acid in the dosage of 0.4% improves intestinal health and performance when nalidixic acid resistant Salmonella Typhimurium is experimentally inoculated.

Avaliou-se o perfil bioquímico do soro de frangos de corte alimentados com a enzima α-amilase produzida por dois microrganismos. Produziram-se dois extratos, um com a-amilase obtida a partir de Cryptococcus flavus em meio de levedura comercial e outro com Aspergillus niger HM2003 em meio de proteína de soja e amido comercial, com atividade de 9,58 U/mL e 10,0 U/mL, respectivamente. Utilizaram-se 360 pintos de corte Cobb 500 de 1 dia de idade e com 49,72 ± 0,68 g de peso vivo inicial. As aves foram alojadas em baterias e foram criadas até os 21 dias de idade. Foram utilizados três dietas, cada uma com cinco repetições de 12 aves, em delineamento inteiramente casualizado. A primeira dieta (basal) foi formulada sem adição de enzima e as outras duas receberam a suplementação de a-amilase produzida por cultivo de Cryptococcus flavus e Aspergillus niger HM2003. Dietas à base de milho e soja foram formuladas em duas fases: pré-inicial (1-7 dias) e inicial (8-21 dias). Na fase pré-inicial, foram observados os seguintes valores médios para cálcio (6,90 e 5,99 mg/dL), proteína plasmática (2,0 e 2,50 g/dL) e fosfatase alcalina (979,98 e 974,66 UI/L), respectivamente para Cryptococcus flavus e Aspergillus niger HM2003. A dieta acrescida de a-amilase obtida a partir de Aspergillus niger HM2003 determinou maior concentração sérica de fósforo. Na fase inicial, os resultados significativos relacionaram-se a potássio quando avaliadas dietas com adição de a-amilase pelas duas fontes. A incorporação das enzimas testadas não proporciona alterações metabólicas ou toxicidade nos animais.

It was evaluated the biochemical serum profile of broilers fed rations supplemented with α-amylase produced by two microorganisms. Two extracts were produced, one was produced with a-amylase obtained from Cryptococcus flavus in a commercial yeast-based medium and the other with Aspergillus niger HM2003 produced in soybean protein and commercial starch medium with activity of 9.58 U/mL and 10.0 U/mL, respectively. A total of 360 Cobb 500 male 1-d broiler chicks with 49.72 ± 0.68 g of initial body weight were used in the experiment. Birds were housed in heated batteries from one to 21 days of age. It was used three diets, each one with five replicates of 12 birds in a complete random design. The first diet (basal) was formulated without the addition of enzyme and the other two were supplemented with a-amylase produced by Cryptococcus flavus and Aspergillus niger HM2003 cultivation. Corn and soybean based diets were formulated in two phases: pre-starter phase (from 1 to 7 days of age) and starter phase (from 8 to 21 days). In pre-starter phase, it was observed the following average values for calcium (6.90 and 5.99 mg/dL), plasma protein (2.0 and 2.5 g/dL) and alkaline phosphatase activity (979.98 e 974.66 UI/L) for Criptococcus flavus and Aspergillus niger HM2003, respectively. Diet added with a-amylase obtained from Aspergillus niger HM2003 increased phosphorus serum concentration. In the starter phase, significative results were related to potassium when diets added with a-amylase were evaluated by the two sources. Incorporation of tested enzymes does not provide metabolic changes neither toxicity in the animals.

Foram investigados os efeitos nutricionais de dois níveis de ácido L-glutâmico (L-Glu) combinados a quatro níveis de vitamina K (vit. K) no soro e no fígado de pintos de corte machos, Hubbard, de 1 dia de idade, criados em baterias aquecidas recebendo dieta básica purificada suplementada com 6,25 e 12,5% de ácido glutâmico combinados a 0,02; 0,2; 2,0 e 20,0 mg de vit. K/kg. Duzentas e cinqüenta e seis aves foram distribuídas em esquema fatorial 2 × 4, em delineamento inteiramente casualizado, com quatro repetições de oito aves. As concentrações de cálcio e a fosfatase alcalina (FA) no soro não diferiram aos 7, 14 e 21 dias de idade. Os níveis séricos de fósforo diferiram aos 21 dias de idade e foram maiores com 12,5% de ácido glutâmico. O peso de fígado foi maior nas aves alimentadas com a dieta com 6,25% de ácido glutâmico e 12,5% de ácido glutâmico + 0,02 mg vit. K/kg. Os níveis séricos de proteínas totais mantiveram-se muito abaixo do normal. As concentrações da enzima glutamato-piruvato transaminase (GPT) foram elevadas nas aves alimentadas com ácido glutâmico e vit. K nos níveis avaliados. A enzima alanina aminotransferase foi encontrada em concentração muito superior aos níveis considerados normais para aves alimentadas com dietas contendo ácido glutâmico e vitamina K nos níveis avaliados. Os níveis de vit. K estudados não afetaram a absorção de cálcio e fósforo e da enzima fosfatase alcalina nem o metabolismo do tecido ósseo. O nível de nitrogênio não-específico (ácido glutâmico) de 6,25% das dietas alterou o metabolismo do tecido ósseo, como resultado da maior concentração de fosfatase alcalina no soro das aves.

Nutritional effects of two levels of L-glutamic acid (L-Glu) combined with four levels of vitamin K (vit. K) in serum and the liver of chicks of day-old broilers, male, Hubbard, raised in brooded batteries, receiving basic purified diet supplemented with 6.25 and 12.5% of L-Glu combined with 0.02, 0.2, 2.0 and 20.0 mg vit. K/kg. Two hundred and fifty birds were allotted to completely randomized design an in 2 × 4 factorial arrangement, with four replications of eight birds each. Calcium and alkaline phosphatase (AP) enzyme concentrations in serum did not differ at 7, 14 and 21 days old. Serum phosphorus levels differed at 21 days and were higher with 12.5% L-Glu. Liver weight was higher in birds fed diet with 6.25% L-Glu and 12.5% L-Glu + 0.02 mg vit. K/kg. Total serum protein remained far below normal levels. Concentrations of the alanine aminotransferase enzyme were high in birds fed L-Glu and vit. K in the evaluated levels. Serum concentrations of alanine aminotransferase enzyme was much higher than that levels considered normal for birds fed diets containing L-Glu and vit. K, in the evaluated levels. Vitamin K levels affected nor the absorption of calcium and phosphorus and the AP enzyme neither the bone tissue metabolism. No-specific nitrogen level (glutamic acid) of 6.25% of the diets changed the metabolism of bone tissue, as a result of the higher concentration of alkaline phosphatase enzyme in the serum of birds.