High-intensity ultrasound improves color and oxidative stability of beef from grain-fed and pasture-fed Nellore cattle.

This research aimed to evaluate the influence of high-intensity ultrasound (HIU) levels (control: 0; high: 747.79; ultra-high: 1344.17 Wcm-2) on pH, instrumental color (redness, R630/580, hue angle and chroma) and oxidative stability (lipid and protein oxidation) of Psoas major (PM) muscle from Nellore cattle raised in two feeding systems: grain and pasture. Using a structural equation modeling (SEM) approach, the relations (P > 0.05) between exogenous (HIU levels) and endogenous (pH, color, lipid and protein oxidation) variables were observed. In beef from grain-fed animals the pH was directly and negatively related to lipid oxidation (γ = -0.321), hue angle (γ = -0.847) and chroma (γ = -0.442) and protein oxidation (γ = -0.752). In PM from pasture-fed HIU exhibited a negative relation with lipid (γ = -0.144) and protein (γ = -0.743) oxidation, suggesting a possible positive influence on the oxidative stability of meat and a positive relation with redness (γ = 0.197) and R630/580 (γ = 0.379). The HIU positively influenced the color and oxidative stability of beef from Bos indicus cattle, and a synergistic effect of HIU and feeding system on beef from pasture-fed animals.

Effect of dairy by-products as milk replacers on quality attributes of ice cream.

The aim of this study was to evaluate the effect of ricotta whey (RW), cheese whey (CW), and butter whey (BUW) as replacers of whole milk (WM) at different ratios (0:100, 25:75, 50:50, 75:25, and 100:0) in the physicochemical and sensory qualities of ice cream. All formulations, including a commercial sample used as reference, were analyzed for nutritional composition, energy value, pH, titratable acidity (TA), melting behavior, desorption index, instrumental color properties, instrumental hardness, and consumer sensory testing. Overall, the addition of RW, CW, and BUW increased the moisture content, TA, melting rate, and redness (a*) and yellowness (b*) values but decreased the pH, lightness (L*) value, energy value, levels of ash, protein, lipid, and carbohydrate. As exception, CW did not influence the TA, and BUW resulted in lower lipid reduction and in lower hardness changes, and it did not affect the content of ash, protein, and a* and b* values of ice creams. Any ice cream formulation had dietary fibers and a desorption index. Ricotta whey and CW at all ratios and BUW at 25% did not affect overall liking compared with the commercial sample, whereas purchase intention was only decreased by the addition of BUW from 50 to 100%. Ricotta whey at 75 and 100% decreased melting velocity and creaminess, and BUW at 50, 75, and 100% increased hardness, TA, and cream flavor but decreased creaminess, which contributed negatively to overall liking. Therefore, the evaluated dairy by-products, especially RW and CW, have great potential for replacing milk in ice creams.

Modelling inactivation of wild-type and clinical Escherichia coli O26 strains using UV-C and thermal treatment and subsequent persistence in simulated gastric fluid.

AIMS: First, two inactivation models were compared for different phenotypic profiles of Escherichia coli O26 using ultraviolet-C light (UV-C) and thermal treatment (T), by means of Central Composite Rotatable Design of Experiment (CCRD). Second, we aimed to evaluate the subsequent survival and persistence of cells in simulated gastric fluid (SGF). METHODS AND RESULTS: Two strains of E. coli O26, a wild-type strain and a clinical ATCC strain were used in both steps. A CCRD was used in a 22 arrangement in random order. The goodness-of-fit of the models was determined. The lack of fit, and the normality of residual data were checked with the Shapiro-Wilk test, and the model accuracy factor, bias factor and the model mean square error (MSE) were measured. Subsequently, the resistance capacity of the strains was evaluated after exposure to simulated gastric acid. The CCRD results obtained indicate that the mild heat (<70°C) has a recovery effect. In addition, for the clinical strain, the UV-C and heat (above 70°C) has an additive inactivation effect. Moreover, temperature (65°C) induced SGF resistance by the wild-type and clinical strain. For the clinical strain, cells exposed to UV-C were more sensitive to SGF. In contrast to clinical strain, exposing cells of the wild-type strain to UV-C increased the survival capacity in the SGF. CONCLUSION: Response surface analyses showed that the wild-type O26 strain has higher persistence under unfavourable conditions than the clinical strain, and the stresses caused by applied microbial control technologies can increase the survival capacity in the SGF. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study shed light on different phenotypic responses in the same bacterium serogroup. Moreover, the impact of the study was that strain selection criteria must be adequate to develop effective models of inactivation.

Comparative genome analysis and characterization of the Salmonella Typhimurium strain CCRJ_26 isolated from swine carcasses using whole-genome sequencing approach.

Salmonella pathogenicity relies on virulence factors many of which are clustered within the Salmonella pathogenicity islands. Salmonella also harbours mobile genetic elements such as virulence plasmids, prophage-like elements and antimicrobial resistance genes which can contribute to increase its pathogenicity. Here, we have genetically characterized a selected S. Typhimurium strain (CCRJ_26) from our previous study with Multiple Drugs Resistant profile and high-frequency PFGE clonal profile which apparently persists in the pork production centre of Rio de Janeiro State, Brazil. By whole-genome sequencing, we described the strain's genome virulent content and characterized the repertoire of bacterial plasmids, antibiotic resistance genes and prophage-like elements. Here, we have shown evidence that strain CCRJ_26 genome possible represent a virulence-associated phenotype which may be potentially virulent in human infection. SIGNIFICANCE AND IMPACT OF THE STUDY: Whole-genome sequencing technologies are still costly and remain underexplored for applied microbiology in Brazil. Hence, this genomic description of S. Typhimurium strain CCRJ_26 will provide help in future molecular epidemiological studies. The analysis described here reveals a quick and useful pipeline for bacterial virulence characterization using whole-genome sequencing approach.

Application of molecular tools to elucidate the microbiota of seafood.

The aim of this review is to present the methodologies currently applied to identify microbiota and pathogens transmitted to humans through seafood consumption, focusing on molecular techniques and pointing out their importance, advantages, disadvantages and applicability. Knowledge of available techniques allows researchers to identify which technique best fits their expectations. With such discernment, it will be possible to infer which disadvantages will be present and, therefore, not interfering with the final result. Two methodologies can be employed for this purpose, dependent and independent cultures. However, the dependent culture has certain limitations that can be solved through the independent cultivation techniques, such as PCR, PFGE and NGS, especially through the sequencing of the 16S rRNA region, providing a complete view of microbial diversity. These have revolutionized microbiological knowledge, mainly because they allow for the identification of uncultivable micro-organisms, which represent a substantial portion of total micro-organisms, making it possible to elucidate not yet described taxa which may display pathogenic potential, besides quantifying microbial communities, microbiota genetics, translated proteins and produced metabolites. In addition, transcriptomic and metabolomic techniques also allow for the evaluation of possible impacts that microbial communities may create in their environment, as well as the determination of potential pathogenicity to humans.

The effect of feed intake containing whole cottonseed on blood parameters of Nellore bulls / Efeito do consumo de rações contendo caroço de algodão sobre parâmetros sanguíneos de bovinos Nelore

The aim of this study was to evaluate the effect of diets containing whole cottonseed (WC) on blood biochemical parameters of bulls. Thirty bulls with 30±6 months and 382.7±28.4kg were kept in feedlot (85 days) and fed the following WC levels: 0, 2.22, 4.44, 6.66, 8.88 and 11.11%. In comparing biochemical indicators from the beginning to the end of the experiment, the control group (CG) and those fed diets containing 2.22, 8.88 and 11.11% of WC had an increase (P<0.05) in serum Ca concentrations (8.34±0.65−9.56±0.92mEqL-1). In relation to Fe (202.79±69.04−300.04±79.88µg/dL), the CG and those treated with 6.66% WC showed an increase (P<0.05) in serum concentrations. As to the Mg (1.92±0.18−2.40±0.27mEqL-1), groups treated with diet containing 2.22, 4.44 and 6.66% of WC had higher (p<0.05) concentrations at the end of the study. Regarding blood lipids, groups with diets containing 2.22; 4.44; 6.66 and 8.88% of WC increased (p<0.05), respectively, in concentrations of HDL, TG, VLDL and COL. The group that received 11.11% of WC increased (P<0.05) in the concentrations of COL and HDL. It can be concluded that diets containing WC, caused no alterations in the concentrations of blood parameters analyzed in this study, with the exception of Mg.(AU)

Objetivou-se avaliar o efeito de dietas contendo caroço de algodão (CA) sobre os parâmetros sanguíneos de bovinos. Trinta touros com 30±6 meses e 382,7±28,4kg foram confinados (85 dias) e receberam dietas com as seguintes proporções de CA: 0; 2,22; 4,44; 6,66; 8,88, e 11,11%. Ao se compararem as concentrações dos indicadores bioquímicos do início com as do final do experimento, foi observado que o grupo controle e aqueles com dietas contendo 2,22; 8,88 e 11,11% de CA apresentaram aumento (P<0,05) na concentração sérica de Ca (8,34±0,65−9,56±0,92 mEqL-1). Já em relação ao Fe (202,79±69,04−300,04±79,88µg/dL), observou-se que apenas o grupo controle e aquele tratado com 6,66% apresentaram aumento (P<0,05) em sua concentração. Quanto ao Mg (1,92±0,18−2,40±0,27 mEqL-1), os grupos tratados com 2,22; 4,44 e 6,66% de CA apresentaram maiores concentrações (P<0,05) ao final do estudo. Com relação aos lipídeos sanguíneos, os grupos com dietas contendo 2,22; 4,44; 6,66 e 8,88% de CA tiveram aumento (P<0,05), respectivamente, nas concentrações de HDL, TG, VLDL e COL. O grupo que recebeu 11,11% de CA teve aumento (P<0,05) nas concentrações de COL e HDL. Conclui-se que as dietas contendo CA não causaram alterações (P>0,05) nas concentrações dos parâmetros sanguíneos analisados, com exceção do Mg.(AU)

Color stability and lipid oxidation of broiler breast meat from animals raised on organic versus non-organic production systems.

The aim of the present research was to evaluate the influence of organic and non-organic production systems on color stability and lipid oxidation of broiler meat Pectoralis major (PM) stored under refrigeration (4°C) for 9 days. PM samples from organic (ORG) and non-organic (NORG) production systems were compared based on physicochemical analyses (instrumental color, myoglobin concentration, metmyoglobin reducing activity (MRA), pH, and lipid oxidation) performed in 4 different trials (n = 4). In general, NORG broilers demonstrated higher (P < 0.05) b* and lipid oxidation values than ORG, whereas ORG samples exhibited increased (P < 0.05) MRA, ratio of reflectance at 630 per 580 nanometers (R 630/580), and a* values. The lower color stability observed in NORG samples can be partly due to lipid oxidation. Therefore, the production system can affect color and lipid stability of broiler breast meat during storage.

Meat characteristics of cattle fed diets containing whole cottonseed / Características da carne de bovinos alimentados com dietas contendo caroço de algodão

Sensory and instrumental analyses evaluated the meat and fat characteristics of feedlot-finished steers fed a diet containing cottonseed. Global impression, texture, meat color, and fat color were assessed. Thirty Nellore bulls with an average age of 30 ± 6 months and initial body weight of 382.7 ± 28.4kg were kept in feedlot stalls and fed the following cottonseed levels: 0; 2.22 %; 4.44 %; 6.66 %; 8.88 %; 11.11 % of the dietary dry matter. The cottonseed used in this experiment had an average free gossypol content of 4.5g/kg of cottonseed. The overall impression of the samples, assessed by the triangle test for difference, did not differ for more than 62 % of the panelists (P>0.01). The shear strength of roasted meat varied from 6.00 to 6.54kg. According to texture profile analysis (TPA), the hardness, springiness, and chewiness of roast meat ranged from 24.15 to 28.01 N, 0.52 to 0.56, 8.42 to 11.01 N, respectively; of raw meat, 9.51 to 13.86 N, 0.26 to 0.29, and 1.38 to 1.81 N, respectively. The different treatments did not affect meat texture, meat color, or fat color (P>0.05). Meat color, luminosity, and red intensity ranged from 37.71 to 42.85, 20.68 to 25.25, and 6.74 to 8.61, respectively; fat color, luminosity, and yellow intensity ranged from 62.26 to 63.78, 11.13 to 11.62, and 10.53 to 10.86, respectively. Cottonseed intake of up to 1.13kg/animal/day, equivalent to a free gossypol intake of 5.05g/animal/day, in place of soybean meal and ground corn, did not significantly change the global sensory impression, texture, and color of the meat and fat.(AU)

Avaliou-se, por meio de análise sensorial e instrumental, o efeito da adição de caroço de algodão à dieta de bovinos confinados sobre as características da carne e da gordura. Foram avaliadas a impressão global, a textura, a cor da carne e a cor da gordura. Trinta touros da raça Nelore, com médias de idade e peso vivo inicial de 30 ± 6 meses e 382,7 ± 28,4kg, foram confinados e receberam dietas com os seguintes teores de caroço de algodão: 0; 2,22%; 4,44%; 6,66%; 8,88%; 11,11% na matéria seca da dieta. O caroço de algodão utilizado neste experimento apresentou conteúdo médio de 4,5g de gossipol livre/kg de caroço de algodão. A impressão global da carne, avaliada por meio de teste triangular de diferença, mostrou que mais de 62% dos provadores não perceberam diferença significativa (P>0,01) entre as amostras. A textura da carne assada avaliada por meio do teste de força de cisalhamento variou de 6,00 a 6,54kg. Na análise do perfil de textura (TPA) da carne assada, a dureza, a elasticidade e a mastigabilidade variaram, respectivamente, de 24,15 a 28,01N, de 0,52 a 0,56N e de 8,42 a 11,01N. Na TPA da carne crua, variaram, respectivamente, de 9,51 a 13,86N, de 0,26 a 0,29N e de 1,38 a 1,81N. Na avaliação da cor da carne, a luminosidade, a intensidade de vermelho e a intensidade de amarelo da cor da carne variaram, respectivamente, de 37,71 a 42,85, de 20,68 a 25,25 e de 6,74 a 8,61. E para a cor da gordura, variaram, respectivamente, de 62,26 a 63,78, de 11,13 a 11,62 e de 10,53 a 10,86. A textura, a cor da carne e a cor da gordura não apresentaram diferenças significativas (P>0,05) entre os diferentes tratamentos. O consumo de caroço de algodão em até 1,13kg/animal/dia, que resultou no consumo de 5,05g de gossipol livre/animal/dia, em substituição ao farelo de soja e ao grão de milho triturado, não causou alterações significativas nas características da carne quanto à impressão sensorial global, à textura, à cor da carne e à cor da gordura.(AU)

Physicochemical evaluation of sheep milk yogurts containing different levels of inulin.

The present study aimed to evaluate the physicochemical parameters of sheep milk yogurt smoothies (SMY) containing inulin at different levels (0, 2, 4, and 6%). Titratable acidity and pH, yogurt bacteria counts, fatty acids profile, and healthy lipid indices were evaluated during 28 d of refrigerated storage. As expected for yogurts, Streptococcus thermophilus counts decreased 1 to 3 log cycles and Lactobacillus delbrueckii ssp. bulgaricus counts decreased 1 to 2 cycles from d 1 to 28. The protective effect of inulin on bacteria survival and viability in the food matrix was not verified in the prebiotic SMY during storage, regardless of inulin level. Although lower post-acidification was observed in prebiotic SMY due to inulin addition, no changes were verified in short-chain fatty acids (SCFA) or polyunsaturated fatty acids (PUFA). In contrast, an increase in medium- and long-chain fatty acids (MCFA and LCFA) and monounsaturated fatty acids (MUFA) was observed during storage in all SMY. The most significant levels of fatty acids in SMY were oleic acid, followed by palmitic and myristic acids. A high positive correlation between conjugated linoleic acid (CLA) and oleic acid (r=0.978) was observed. The cis-9,trans-11 CLA isomer represented approximately 78% of total PUFA and 2% of total fatty acids, whereas α-linoleic acid comprised about 22% PUFA and 1% of total fatty acids in SMY. The fatty acid changes during storage were associated with the metabolic activity of the starter bacteria, especially for oleic acid and cis-9,trans-11 CLA isomer. Thus, the SMY represented a great source of these compounds. We observed that inulin levels did not affect fatty acids. A nonsignificant decrease in atherogenic index was observed during storage in all SMY, and a positive correlation (r=0.973) was found between atherogenic index and thrombogenic index of SMY. High correlations were observed between lauric and myristic acids and saturated fatty acids (r=0.907 and r=0.894, respectively), providing evidence of their atherogenic and thrombogenic potential. A negative correlation was observed between stearic acid and atherogenic index (r=-0.612) and between oleic acid and atherogenic index. Sheep milk yogurt could be characterized as a food with low atherogenic and thrombogenic risk because of its healthy lipid composition. Therefore, addition of inulin to SMY could be a good option to improve functionality of this food matrix for dairy companies wishing to enter the functional food market.

Physico-chemical changes during storage and sensory acceptance of low sodium probiotic Minas cheese added with arginine.

The partial substitution of sodium chloride by potassium chloride (0%, 25%, and 50%) and addition of arginine (1% w/w) in probiotic Minas cheese was investigated. Microbiological (Lactococcus lactis and Lactobacillus acidophilus counts, and functionality of the prebiotics L. acidophilus), physicochemical (pH, proteolysis, organic acids, fatty acids, and volatile profiles), rheological (uniaxial compression) and sensory (hedonic test with 100 consumers) characterizations were carried out. The sodium reduction and addition of arginine did not constitute a hurdle to lactic and probiotic bacteria survival, with presented values of about 9 log CFU/g, ranging from 7.11 to 9.21 log CFU/g, respectively. In addition, lower pH values, higher proteolysis, and a decrease in toughness, elasticity and firmness were observed, as well as an increase in lactic, citric, and acetic acid contents. In contrast, no change was observed in the fatty acid profile. With respect to the sensory acceptance, the probiotic low-sodium Minas cheese presented scores above 6.00 (liked slightly) for the attributes flavor and overall acceptance. The addition of arginine can be a potential alternative for the development of probiotic dairy products with reduced sodium content.