Jaboticaba yoghurts enriched with whey protein or albumin: evaluation of phenolic content and color / Iogurtes de jabuticaba adicionados de proteína do soro do leite ou albumina: avaliação do conteúdo fenólico e cor

In the present study, nonfat yoghurt made with whey protein isolate (WPI) or pasteurized egg white powder (albumin) was added with syrup containing jaboticaba pulp and lyophilized jaboticaba peel flour and six experimental groups were made: control yoghurt (CY); WPI yoghurt (WY); albumin yoghurt (AY), syrup yoghurt and WPI (WSY); syrup and albumin yoghurt (ASY) and syrup yoghurt (SY). This study aimed to verify the influence of the addition of fruit syrup on the phenolics compounds and on the instrumental color parameters of yoghurts made with proteins on the 1st and 28th day of storage. There was a significant decrease in total phenolics content in yoghurt containing WPI and syrup (from 1408.14mg GAE.L-1 to 686.73mg GAE.L-1), as well as total anthocyanin content. However, yoghurt containing syrup and albumin showed an increase in total flavonoid content on day 28 of storage (from 28.30mg QE.100g-1 to 38.29mg QE.100g-1). Regarding color, there was an increase in L* and b* values in yoghurt containing syrup and WPI and in yoghurt containing syrup and albumin. For a* values, a decrease was observed at the end of the storage period in samples containing protein (WPI or albumin) and syrup. The data showed that the addition of jaboticaba syrup to yoghurts containing different proteins provided different phenolics compounds contents at the end of the storage period, and different color parameters to the final product.

No presente estudo, iogurtes desnatados feitos com proteína isolada do soro do leite (PIS) ou albumina isolada da clara do ovo pasteurizada em pó (albumina) foram adicionados de xarope contendo a polpa da jabuticaba e a farinha liofilizada da casca da jabuticaba, obtendo-se seis grupos experimentais: iogurte controle (CY); iogurte PIS (WY); iogurte albumina (AY); iogurte xarope e PIS (WSY); iogurte xarope e albumina (ASY) e iogurte com xarope (SY). Neste estudo objetivou-se verificar a influência da adição do xarope da fruta nos compostos fenólicos e nos parâmetros instrumentais de cor dos iogurtes elaborados com proteínas no 1oe 28o dia de armazenamento. Houve uma diminuição significativa no teor de fenólicos totais no iogurte contendo PIS e xarope (de 1408.14mg GAE.L-1para 686.73mg GAE.L-1), bem como no teor de antocianinas (de 158.45mg cyanidin-3-glucoside.L-1para 56.45mg cyanidin-3-glucoside.L-1). No entanto, os iogurtes contendo xarope e albumina apresentaram um aumento no teor de flavonóides totais no 28o dia de armazenamento (de 28.30mg QE.100g-1para 38.29mg QE.100g-1). Em relação a cor houve um aumento dos valores de L* e no valor de b* no iogurte contendo xarope e PIS e no iogurte contendo xarope e albumina. Já para os valores de a* foi observado uma diminuição ao final do período de armazenamento nas amostras contendo proteína (PIS ou albumina) e xarope. Os dados demonstraram que a adição do xarope de jabuticaba a iogurtes contendo diferentes proteínas proporcionaram diferentes conteúdos de compostos fenólicos ao final do período de estocagem, e diferentes parâmetros de cor ao produto final.

Jaboticaba yoghurts enriched with whey protein or albumin: evaluation of phenolic content and color / Iogurtes de jabuticaba adicionados de proteína do sorodo leite ou albumina: avaliação do conteúdo fenólico e cor

In the present study, nonfat yoghurt made with whey protein isolate (WPI) or pasteurized egg white powder (albumin) was added with syrup containing jaboticaba pulp and lyophilized jaboticaba peel flour and six experimental groups were made: control yoghurt (CY); WPI yoghurt (WY); albumin yoghurt (AY), syrup yoghurt and WPI (WSY); syrup and albumin yoghurt (ASY) and syrup yoghurt (SY). This study aimed to verify the influence of the addition of fruit syrup on the phenolics compounds and on the instrumental color parameters of yoghurts made with proteins on the 1st and 28th day of storage. There was a significant decrease in total phenolics content in yoghurt containing WPI and syrup (from 1408.14mg GAE.L-1 to 686.73mg GAE.L-1), as well as total anthocyanin content. However, yoghurt containing syrup and albumin showed an increase in total flavonoid content on day 28 of storage (from 28.30mg QE.100g-1 to 38.29mg QE.100g-1). Regarding color, there was an increase in L* and b* values in yoghurt containing syrup and WPI and in yoghurt containing syrup and albumin. For a* values, a decrease was observed at the end of the storage period in samples containing protein (WPI or albumin) and syrup. The data showed that the addition of jaboticaba syrup to yoghurts containing different proteins provided different phenolics compounds contents at the end of the storage period, and different color parameters to the final product.

No presente estudo, iogurtes desnatados feitos com proteína isolada do soro do leite (PIS) ou albumina isolada da clara do ovo pasteurizada em pó (albumina) foram adicionados de xarope contendo a polpa da jabuticaba e a farinha liofilizada da casca da jabuticaba, obtendo-se seis grupos experimentais: iogurte controle (CY); iogurte PIS (WY); iogurte albumina (AY); iogurte xarope e PIS (WSY); iogurte xarope e albumina (ASY) e iogurte com xarope (SY). Neste estudo objetivou-se verificar a influência da adição do xarope da fruta nos compostos fenólicos e nos parâmetros instrumentais de cor dos iogurtes elaborados com proteínas no 1º e 28º dia de armazenamento. Houve uma diminuição significativa no teor de fenólicos totais no iogurte contendo PIS e xarope (de 1408.14mg GAE.L-1 para 686.73mg GAE.L-1), bem como no teor de antocianinas (de 158.45mg cyanidin-3-glucoside.L-1 para 56.45mg cyanidin-3-glucoside.L-1). No entanto, os iogurtes contendo xarope e albumina apresentaram um aumento no teor de flavonóides totais no 28º dia de armazenamento (de 28.30mg QE.100g-1 para 38.29mg QE.100g-1). Em relação a cor houve um aumento dos valores de L* e no valor de b* no iogurte contendo xarope e PIS e no iogurte contendo xarope e albumina. Já para os valores de a* foi observado uma diminuição ao final do período de armazenamento nas amostras contendo proteína (PIS ou albumina) e xarope. Os dados demonstraram que a adição do xarope de jabuticaba a iogurtes contendo diferentes proteínas proporcionaram diferentes conteúdos de compostos fenólicos ao final do período de estocagem, e diferentes parâmetros de cor ao produto final.

Atividade bactericida e bacteriostática da casca do pequi (Caryocar brasiliense) em bactérias deteriorantes e patogênicas isoladas de alimentos / Bactericidal and bacteriostatic activity of pequi (Caryocar brasiliense) against deteriorant and pathogenic bacteria from foods

O pequi é uma fruta nativa do Cerrado brasileiro que apresenta elevado teor de compostos antioxidantes e pode apresentar ação antimicrobiana. Dessa forma, objetivou-se com o presente trabalho avaliar a atividade bacteriostática e bactericida do extrato da casca do pequi. Das cepas estudadas 5 são padrões cedidos pela FIOCRUZ e 5 são bactérias de alta resistência a antimicrobianos isoladas de carne e frango. Foi determinada a concentração inibitória mínima (CIM) e concentração bactericida mínima do extrato da casca do pequi. O extrato da casca do pequi apresenta atividade antimicrobiana frente a bactérias patogênicas e deteriorantes. C. jejuni e C. colisão as mais sensíveis. S. aureus apresentou tolerância. E. coli O157:H7 e E. coli são menos sensíveis. O resíduo do pequi é uma potencial e importante fonte de antimicrobianos naturais.

Ação do extrato do resíduo de Caryocar brasiliense frente a formação de biofilme dos principais microrganismos veiculados por produtos de origem animal / Action of the Caryocar brasiliense waste extract against the biofilm formation of the main microorganisms carried by products of animal origin

Objetivou-se com o presente estudo avaliar a inibição da formação de biofilme pelo extrato do resíduo do pequi frente a microrganismos patogênicos e deteriorantes de alimentos. A casca do pequi foi obtida de frutas coletadas na cidade de Montes Claros/MG, foi seca em estufa de ventilação forçada, moída e peneirada em 250 Mesh. Seu extrato foi obtido em micro-ondas analítico. Foram utilizadas cinco cepas padrão e cinco isolados de produtos de origem animal, que foram reativadas e confirmado a sua pureza em ágar específico. Para avaliar a formação do biofilme foram utilizadas microplacas esterilizadas, sendo adicionados 90µL de BHI com 1% de glicose, 10µL da suspensão de cada bactéria e o extrato em diferentes concentrações. Concluiu-se que o extrato da casca do pequi inibe a formação de biofilme por bactérias patogênicas e deteriorantes.

Molecular Detection, Typing, and Quantification of Campylobacter spp. in Foods of Animal Origin.

The most frequently reported zoonosis and the main bacterial foodborne disease infection in humans is caused by Campylobacter spp., and C. jejuni and C. coli are the most common types. These bacteria can be found in the intestinal tracts of cattle, dogs, cats, sheep, poultry and pigs. The isolation of this microorganism is laborious because it requires specific media and a low oxygen concentration for growth. Additionally, differentiation between species through conventional bacteriology is difficult, as there are few different biochemical characteristics among the various species. Molecular microbiological techniques have become more important and are now broadly applied to help overcome difficulties in the identification, differentiation, and quantification of this pathogen. To date, there have been advances in the development and use of molecular techniques for the identification of microorganisms in foodstuffs. Tools such as pulsed-field gel electrophoresis and multilocus sequence typing are the most commonly used for typing. For the identification and confirmation of species, polymerase chain reaction (PCR) is crucial. Quantification by real-time PCR has wide applicability. To identify strains and antimicrobial resistance genes, sequencing technologies have been applied. This review builds on the discussion about the main and most widely used molecular methods for Campylobacter, as well as methods showing better potential for the classification, identification, and quantification of this important pathogen.

Simultaneous analysis of carbohydrates and organic acids by HPLC-DAD-RI for monitoring goat's milk yogurts fermentation.

During yogurt manufacture, the lactose fermentation and organic acid production can be used to monitor the fermentation process by starter cultures and probiotic bacteria. In the present work, a simple, sensitive and reproducible high-performance liquid chromatography with dual detectors, diode array detector and refractive index was validated by simultaneous analysis of carbohydrates and organic acids in goat milk yogurts. In addition, pH and bacterial analysis were performed. Separation of all the compounds was performed on an Aminex HPX-87H column (300×7.8 mm, 9 µm) utilizing a 3 mmol L(-1) sulfuric acid aqueous mobile phase under isocratic conditions. Lactose, glucose, galactose, citric, lactic and formic acids were used to evaluate the following performance parameters: selectivity, linearity, precision, limit of detection (LOD), limit of quantification (LOQ), decision limits (CCα), detection capabilities (CCß), recovery and robustness. For the method application a six goat milk yogurts were elaborated: natural, probiotic, prebiotic, symbiotic, cupuassu fruit pulp, and probiotic with cupuassu fruit pulp. The validated method presented an excellent selectivity with no significant matrix effect, and a broad linear study range with coefficients of determination higher than 0.995. The relative standard deviation was lower than 10% under repeatability and within-laboratory reproducibility conditions for the studied analytes. The LOD of the method was defined from 0.001 to 0.003 µg g(-1), and the LOQ from 0.003 to 0.013 µg g(-1). The CCα was ranged from 0.032 to 0.943 µg g(-1), and the CCß from 0.053 to 1.604 µg g(-1). The obtained recovery values were from 78% to 119%. In addition, the method exhibited an appropriate robustness for all parameter evaluated. Base in our data, it was concluded that the performance parameters demonstrated total method adequacy for the detection and quantification of carbohydrates and organic acids in goat milk yogurts. The application of the method was successfully applied to monitoring different goat milk yogurts during fermentation.

Detection of fluoroquinolone resistance by mutation ingyrA gene of Campylobacterspp. isolates from broiler and laying (Gallus gallus domesticus) hens,from Rio de Janeiro State, Brazil / Detecção de resistência às fluoroquinolonas através da mutação no gene gyrA em Campylobacter spp. isolados de frangos de corte e galinhas (Gallus gallus domesticus) poedeiras, no Estado do Rio de Janeiro, Brasil

Poultry are considered to be the main reservoir of Campylobacterspp. bacteria, an important pathogen for humans. Many studies have reported a rapid selection of fluoroquinolone-resistant strains following the widespread use of these antimicrobials in poultry production and human medicine. The main mechanism of fluoroquinolone resistance in Campylobacteris a mutation in the Quinolone Resistance Determinant Region (QRDR) in the gyrA gene, which codes for the subunit of the enzyme DNA gyrase, the target for fluoroquinolone. The aim of this study was to investigate the mutation in QRDR in the gyrA gene of Campylobacterstrains previously isolated from broiler carcasses and feces of laying hens. Thirty-eight strains of C. jejuniand 19 C. colistrains (n=57), previously characterized as resistant to ciprofloxacin and enrofloxacin by the disk diffusion method and minimum inhibitory concentration (MIC), were selected. For detection of the mutation, a fragment of 454pb QRDR in the gyrA gene was used for direct sequencing. All strains presented the QRDR mutation in the gyrA gene at codon 86 (Thr-86-Ile), which confers resistance to fluoroquinolones. Other known silent mutations were observed. This genotypic characterization of fluoroquinolone resistance inCampylobacterstrains has confirmed the prior phenotypic detection of the resistance. The Thr-86-Ile mutation was observed in all samples confirming that this is the predominant mutation in enrofloxacin and ciprofloxacin resistant strains of C. jejuniand C. coli.

As aves são consideradas o principal reservatório deCampylobacterspp., um importante patógeno para humanos e muitos estudos têm relatado uma rápida seleção de cepas resistentes às fluoroquinolonas após o uso destes antimicrobianos na produção avícola e na medicina humana. O principal mecanismo de resistência às fluoroquinolonas em Campylobacterconsiste na mutação na Região Determinantes de Resistência às Quinolonas (RDRQ) do gene gyrA, que codifica para a subunidade A da enzima DNA girase, alvo das fluoroquinolonas. O objetivo deste estudo foi investigar a mutação na RDRQ do gene gyrA em cepas de Campylobacterpreviamente isolados de carcaças de frangos de corte e fezes de galinhas poedeiras. Foram selecionadas 38 cepas de C. jejunie 19 cepas de C. coli(n=57), previamente caracterizadas como resistentes à ciprofloxacina e enrofloxacina, pelo método da difusão em disco e pela determinação da concentração inibitória mínima. Para detecção da mutação, foi utilizado sequenciamento direto de um fragmento de 454pb da RDRQ do gene gyrA gerado por PCR. Todas as cepas apresentaram a mutação na RDRQ do gene gyrA no códon 86 (Tre-86-Ile), que confere resistência às fluoroquinolonas e outras mutações silenciosas foram observadas. A caracterização genotípica da resistência às fluoroquinolonas em Campylobacterconfirmou a prévia detecção fenotípica dessa resistência e a mutação Tre-86-Ile foi observada na totalidade das amostras, comprovando ser esta a mutação predominante em cepas de C. jejunie C. coliresistentes à enrofloxacina e ciprofloxacina.