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A new procedure for the determination of biogenic amines (BAs), putrescine, cadaverine, spermidine, spermine and tyramine, based on the purification through precipitation and centrifugation of peptides in an acid extract from the sample is proposed. The novelty of the procedure in relation to the liquid-liquid purification reported in the literature is based on shortening the time of analysis and reducing BAs losses during sample preparation. The procedure permitted better precision, recovery, and sensibility, particularly in lower concentration levels, when compared to extraction without purification before derivatization. The method was applied to the simultaneous determination of the five aforementioned BAs in commercial yogurt samples by reversed-phase high-performance liquid chromatography (RP-HPLC). The procedure presented adjusted correlation coefficients between 0.980 and 0.997, and linear range in samples of 1–50 mg L−1 (cadaverine), 3–50 mg L−1 (putrescine, spermidine and spermine) and 5–50 mg L−1 (tyramine), with accuracy ranging from 67.81% to 142.78% in the limit of quantification (LOQ) and from 88.99% to 118.26% in other concentration levels. The limit of detection of BAs in yogurt samples was 0.18–4.01 mg L−1, while LOQ ranged between 1 and 5 mg L−1. The intraday relative standard deviation was ≤15.74% in LOQ and ≤10.05% in other concentration levels. The purification step by precipitation was fundamental to eliminate the interferences present in the yogurt samples, and it was relevant to increase the sensitivity of BAs detection when compared to liquid-liquid purification. Keywords: Extract purification, Sample preparation, In-house validation method, Tyramine, Cadaverine, Putrescine, Fermented milk, FDA Guidelines, Decision limits, Detection capabilities

Cheese ripening involves lactose metabolism, lipolysis and proteolysis, which are affected by many factors. The aim of this study was to assess changes due to ripening (90 days) of goat milk cheese through bacteriological and physicochemical analysis in order to verify if, at the end of ripening period, this cheese could be considered “lactose-free”. Three batches of the goat milk cheese were manufactured and ripened at 10 °C and 80% relative humidity for 90 days. Titratable acidity increased by about 59 °D due to carbohydrate degradation and organic acid production. However, pH (5.31–5.25) remained constant. Lactococcus was the dominant cheese microbiota, acting in the fermentation of lactose (1.17–0.06 mg/g) and lactic acid production (5.49–s10.01 mg/g). Thus, ripening time was decisive for bacteriological and physicochemical goat milk cheese characteristics. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10068-019-00682-w) contains supplementary material, which is available to authorized users.

Fowls are the main reservoirs of the highly important food-originating pathogen called Campylobacter spp. and broilers’ meat and byproducts are the main vehicles of this microorganism. Increasing of Campylobacter spp. resistant strains to fluorquinolones, an antimicrobial class often employed in poultry farming and in human medicine has become a great concern to poultry breeders. In fact, several studies evaluated increasing bacterial resistance against these antimicrobial agents. The role of CmeABC efflux system has been underscored among the resistance mechanisms in Campylobacter spp. to fluorquinolones. This study investigated the occurrence of CmeABC efflux pump in 81 and 78 enrofloxacin resistant strains of Campylobacter jejuni and C. coli respectively, isolated from broilers collected from six abattoirs situated at São José do Vale do Rio Preto/RJ poultry center and from two commercial abattoirs situated at Metropolitan Region of Rio de Janeiro, from 2013 to 2016. The resistance to enrofloxacin was assessed by agar dilution to determine minimum inhibitory concentration (MIC). The CmeABC efflux system was investigated through the detection of genes genes cmeA, cmeB and cmeC by PCR. The activity of CmeABC efflux pump was investigated in 20 strains by using the efflux pump inhibitor Phenylalanine-Arginine β-Naphthylamide (PAβN). The three genes cmeA, cmeB and cmeC were detected in 94.3% of the strains (C. jejuni = 80 and C. coli = 70), whereas the system was absent or incomplete in 5.7% of strains (C. jejuni = 1 and C. coli = 8). MIC varied between 0.5μg/ml and 64μg/ml, and 88.7% of strains were enrofloxacin resistant and 11.3% featuring intermediate resistance. The inhibition of the efflux pump by PAβN reduced the MIC to enrofloxacin up to eight times in fifteen strains (75%). These results indicate that this system is frequent and active in Campylobacter spp. Resistant strains in the presence of enrofloxacin. RESUMO: As aves são os principais reservatórios de Campylobacter spp., importante patógeno de origem alimentar e a carne de frango e produtos derivados são os principais veículos desse microrganismo. O aumento de cepas de Campylobacter spp. resistentes às fluorquinolonas, uma classe antimicrobiana frequentemente empregada na avicultura e na medicina humana, tornou-se uma grande preocupação para os produtores de aves e vários estudos avaliaram o aumento da resistência bacteriana a esses antimicrobianos. O papel do sistema de efluxo CmeABC tem sido enfatizado entre os mecanismos de resistência em Campylobacter spp. à fluorquinolonas. O presente estudo investigou a ocorrência da bomba de efluxo CmeABC em 81 cepas de Campylobacter jejuni e 78 cepas de Campylobacter coli resistentes à enrofloxacina, isoladas de frangos de corte coletados em seis abatedouros situados no polo avícola de São José do Rio Preto/RJ e de dois abatedouros comerciais situados na Região Metropolitana do Rio de Janeiro, de 2013 a 2016. A resistência à enrofloxacina foi avaliada pelo método de diluição em ágar para determinar a concentração inibitória mínima (CIM). O sistema de efluxo CmeABC foi investigado através da detecção dos genes cmeA, cmeB e cmeC por PCR. A atividade da bomba de efluxo CmeABC foi investigada em 20 cepas utilizando o inibidor da bomba de efluxo Phenylalanine-Arginine β-Naftilamida (PAβN). Os três genes cmeA, cmeB e cmeC foram detectados em 94,3% das cepas (C. jejuni = 80 e C. coli = 70), enquanto o sistema estava ausente ou incompleto em 5,7% das cepas (C. jejuni = 1 e C coli = 8). A CIM variou entre 0,5μg/ml e 64μg/ml e 88,7% das cepas foram resistentes à enrofloxacina, enquanto 11,3% apresentaram resistência intermediária. A inibição da bomba de efluxo pelo PAβN reduziu a CIM da enrofloxacina até oito vezes em quinze cepas (75%). Estes resultados indicam que este sistema é frequente e ativo em cepas resistentes de Campylobacter spp. na presença de enrofloxacina.

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.

Despite goat milk having health benefits over cow milk, goat milk yogurt (GY) presents low consistency and viscosity, which reduces its overall acceptability by the consumer. Thus, new innovative methods can be an alternative to improve the quality of GY. Hence, this study aimed to investigate the effect of ultrasound (US) treatment with different sonication times on quality parameters of probiotic GY during refrigerated storage. US treatment was conducted at 20 KHz for 3, 6, and 9 min in yogurt. Lactobacillus bulgaricus and Lactobacillus acidophilus LA-5 were sensitive to US treatment, presenting a decrease in the yogurts stocked. This loss of viability led to reduced post-acidification due to smaller lactose metabolization in yogurt samples submitted to the US. Among tested treatments, the application of 6 min enhanced the apparent viscosity and consistency index of GY yogurts. In addition, this time also reduced tyramine and total biogenic amine (BAs) content. These findings suggest that 6 min of sonication is a promising way to improve the rheological properties and reduce the acidity and BAs content in GY. Further studies should be performed to optimize the US setting conditions to preserve the probiotic culture viability in yogurts.

Processing may affect the bioactivity of soy food products, due to the conversion between isoflavones’ chemical forms. We investigated the effect of dry-heating or fermentation by Saccharomyces cerevisiae on soybean meal (SBM) chemical composition, with emphasis on isoflavone glycosides to aglycones conversion. Biscuits were prepared with aglycone-rich SBM and evaluated regarding their technological, nutritional, functional and sensory properties. Fermentation yielded more isoflavone aglycones (7.8-fold) than dry-heating (2.5-fold). Fermentation improved nutritional quality (50% increase in fiber, and 32%, 83% and 69% decreases in carbohydrate, lipid and trypsin inhibitors, respectively) and increased antioxidant activity (up to 206%) of SBM. Soybean meal biscuits showed adequate technological properties and improved nutritional and functional qualities in comparison to wheat biscuits (up to 3.7-, 4.6-, 2.8- and 4.7-fold increases in protein, dietary fiber, ash and antioxidant activity, respectively; 2.1-fold decrease in carbohydrate). SBM biscuits showed good sensory acceptance, whereas fermented SBM biscuits showed low sensory scores.

Juçara (Euterpe edulis) is a native Brazilian palm tree from the Atlantic Forest, whose fruit-processing waste can present high concentration of antioxidant compounds. This research was assessed to determine the antioxidant potential of juçara waste extracts aiming to reduce the lipid and protein oxidation processes on conventional and antibiotic-free broiler meat throughout 9 d during refrigerated storage. The juçara waste extracts were obtained by microwave-assisted extraction. Two different extracts were tested based on the optimum point obtained when checking total phenolic (TPC) contents (Extract P) and antioxidant activity (Extract A) based on a previous study. The treatments using conventional and antibiotic-free broiler meat included: chicken patties without antioxidant addition (AFBNC and CBNC), with synthetic antioxidant (BHT) (AFBPC and CBPC), with Extract P (AFBEP and CBEP) and with Extract A (AFBEA and CBEA), totaling 8 treatments. Antioxidant activity of extracts along with TPC, flavonoid, anthocyanin, and tannin contents of extracts and patties were assessed. Proximate composition, fatty acid profile, lipid and protein oxidation process, and instrumental color were analyzed in patty treatments. Although both extracts had similar content of TPC and tannin, extract A presented the highest anthocyanin, while extract P exhibited the highest flavonoid. While extract A exhibited the highest antioxidant activity, extract P was highly influential in the stability of lipid oxidative degradation in both types of broiler meat (AFBEP and CBEP), and as successful as BHT (AFBPC and CBPC). In addition, extract P was also able to stabilize protein oxidation in conventional broiler meat (CBEP) from the third day, until the end of the storage period. Therefore, the fruit waste extract P of juçara can be a promising source of natural antioxidants to prevent the oxidative process in conventional and antibiotic-free broiler meat.

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.

The aim of this study was to assess the chemical quality and instrumental texture parameters, as well as their relationships, of five Brazilian freshwater fish species stored at 4 °C for 6 days. In general, ammonia, TCA-soluble peptides, and biogenic amine values increased with storage time, attributed to the advance of the deterioration process. Ammonia and TCA-soluble peptide concentrations correlated positively with the increase of putrescine, spermine, and histamine. Putrescine production began during the first days of storage, while cadaverine was produced later. Spermine and spermidine showed variable behavior, increasing and decreasing, respectively. With regard to the instrumental texture parameters, firmness, hardness, and chewiness decreased at the beginning of the storage period, whereas an increase was observed in springiness. All instrumental texture parameters demonstrated high correlations with ammonia and TCA-soluble peptides. The increase in certain biogenic amines (putrescine, cadaverine, and spermine) seems to correlate well with decreases observed in firmness, hardness, and chewiness. In addition, a strong relationship was observed between the initial days of storage and instrumental texture parameters, while a significant correlation between the end of the storage and the chemical quality analyses was verified. Firmness, hardness, chewiness, and cohesiveness were considered parameters with high potential in the evaluation of fish freshness during the first days of storage, whereas the chemical quality analyses and springiness were considered important for later evaluation of fish quality. Therefore, instrumental texture parameters may be used as quality indicators in the evaluation of freshwater fish freshness.

Although the demand for goat milk products has been growing, they have lower consumer acceptability than products derived from cow milk. However, the addition of cupuassu pulp can be used to improve the formulation of these products. For this reason, the aim of this study was to investigate the influence of new goat milk yogurt manufactured with cupuassu pulp on physicochemical properties, consumers' perceptions, and overall consumer acceptance. In addition, the effect of antioxidant health information on consumer acceptance and purchase intention of cupuassu goat milk yogurts was evaluated. The results demonstrated a positive expectation regarding linking and familiarity to goat milk products and products with cupuassu pulp. The pH, total phenolic content, lightness, redness, yellowness, and apparent viscosity were potentially affected by the addition of cupuassu, with the highest concentration of cupuassu (10%) exhibiting the greatest changes in parameters. Based on principal component analysis, partial least squares regression, and just-about-right and penalty analysis, the addition of cupuassu pulp improved some sensory attributes of goat milk yogurt, such as cupuassu aroma, cupuassu flavor, yellow color, consistency, and viscosity, which positively influenced product acceptance. In addition, antioxidant health information increased the acceptance and purchase intention of cupuassu goat milk yogurts. Taking into account the parameters investigated in this study, the best scoring formulation was goat milk yogurt with 10% cupuassu pulp. Our results suggest that cupuassu pulp can be considered a potential ingredient to improve the sensory and texture properties of goat milk yogurt. Furthermore, the antioxidant health information could be a sensory strategy to increase the acceptance of cupuassu goat milk yogurts.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior FAPERJ - Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro Bioactive amines (BAs) represent a considerable toxicological risk in fermented dairy products because they provide the ideal environment for their formation. Thus, secondary control measures to prevent or reduce BAs formation in dairy products are urgently needed. However, additional scientific knowledge about the factors affecting BAs production and the interaction among them is currently necessary to achieve this goal. In this context, Partial Least Square with Variable Importance in Projection (PLS-VIP) analysis followed by cross-validation was applied to variables to investigate their interactive effect on BAs accumulation in cow's and goat's fermented milk during refrigerated storage. Streptococcus thermophilus and Lactobacillus acidophilus LA-5 increased tyramine and total BAs content in both cow's (CFM) and goat's (GFM) fermented milks. In CFM, Maillard reaction involving galactose and increased post acidification interacted to enhance accumulation of BAs (R2 = 0.895, P = 1.11 × 10−5); whereas for GFM, losses of consistency coefficient and viscosity were essential for BAs accumulation (R2 = 0.919; P = 2.72 × 10−6). These findings show that by preventing Maillard reaction and delaying post acidification in CFM, as well as by controlling viscosity in GFM, there can be mitigation of BAs formation during storage.

To investigate the prevalence of Campylobacter and Salmonella in poultry carcasses in state of Rio de Janeiro, Brazil, 60 samples from 6 slaughterhouses were collected over a period of 6 months. A total of 82 Campylobacter isolates were obtained from twenty seven (45%) positive chicken carcasses, including 44 isolates (53.66%) of Campylobacter jejuni and 38 (46.34%) of Campylobacter coli. The identification of all strains was confirmed by PCR. Salmonella was isolated from 4 (6.67%) carcasses by conventional method and was detected in 5 (8.33%) of 60 chicken carcasses by PCR. Two Salmonella Albany and two Salmonella Typhimurium were identified. Antimicrobial susceptibility testing was primarily done by the disk diffusion method and later by assessing minimum inhibitory concentrations (MICs) against all the isolates. All the Campylobacter isolates were resistant to ciprofloxacin and enrofloxacin. It was observed high MIC values for enrofloxacin (64 mg/mL) in one C. jejuni and two C. coli strains, and for ciprofloxacin ( 128 mg/mL) in one C. jejuni and three C. coli strains. No Salmonella isolate was resistant to these antibiotics by both methods. These findings reveal a broad extent of fluoroquinolone resistance in Campylobacter isolates from chicken carcasses in Brazil and underline the need for prudent use of these antibiotics in poultry production to minimize the spread of fluoroquinolone resistant Campylobacter.

Sodium chloride reduction in foods is a significant focus of the dairy industry; however, it can interfere with dairy product quality. Thus, researchers have carried out studies on alternatives to maintain dairy product safety when presenting reduced NaCl content, such as natural antimicrobial addition. Caryocar brasiliense (pequi) is a fruit with high phenolic compound concentrations in the pulp and peel and known antioxidant and antimicrobial properties. This study aimed to define the optimum stage for pequi waste extract addition during cheese manufacturing in order to maintain and prolong the shelf life of reduced-sodium goat Minas Frescal cheese. Four different goat Minas Frescal cheese treatments were carried out: control cheese (without extract; CC), pequi extract addition to milk (CM), pequi extract addition to mass (CS), and cheese immersion in pequi extract (CIE). The treatments were subjected to microbiological (Staphylococcus spp., Escherichia coli, Enterobacteriaceae, coliforms and fecal coliforms, Lactococcus spp., and lactic acid bacteria counts), textural (hardness and consistency), and instrumental color (luminosity, yellow intensity, red intensity, chroma, hue angle, and total color change) analyses. No Enterobacteriaceae, Staphylococcus spp., E. coli, or coliforms and fecal coliforms were detected during storage for any of the assessed samples, including CC. Regarding texture, all samples presented a trend for decreasing rigidity during storage. In addition, lower luminosity values were also observed in cheeses produced with added pequi extract (CM, CS, and CIE) when compared with CC. All cheeses produced with added pequi were stable regarding all evaluated parameters; however, pequi extract addition to milk (CM) was shown to be more efficient, leading to higher textural parameters and better microbiological quality during storage. Thus, the CM treatment is the most recommended for pequi waste extract addition during Minas Frescal cheese manufacture.

Biogenic amines (BAs) are low-molecular-weight organic bases, which possess biological activity. In food, the presence of BAs as histamine and tyramine is a public health concern being the most notorious food-borne intoxications. BAs can be detected in raw and processed foods that are formed and degraded through several pathways during the metabolic processes of animals, plants, and microorganisms. The BAs analyses are very important because they are considered as indicators of food quality and safety. Some bacteria are usual contaminants of food and have been described with the ability to produce BAs, which can be the result of failures in manufacturing practices, poor quality, or insufficient hygienic conditions. Hence, BAs can be used as a quality index for meat, fish, and dairy products. In addition, some lactic acid bacteria strains can also contribute to BAs production and this group is mainly responsible for their synthesis in fermented foods. Consequently, the control of BAs in food is a challenge for the food industry.

Resumo Estudos têm revelado que a resistência às quinolonas em cepas de Campylobacter está relacionada à presença da mutação Treonina-86 para Isoleucina. Com o objetivo de investigar a presença dessa mutação em cepas de Campylobacter sensíveis e resistentes à ciprofloxacina e enrofloxacina, o conteúdo cecal de 80 frangos de corte de criação orgânica, abatidos sob Serviço de Inspeção Estadual (S.I.E.) do Estado do Rio de Janeiro, foram coletados e investigados para a presença de Campylobacter. A determinação da resistência à ciprofloxacina e enrofloxacina foi feita pela técnica de difusão em disco e de diluição em ágar para determinação da Concentração Inibitória Mínima (CIM). A detecção da mutação na Região Determinante de Resistencia às Quinolonas (RDRQ) no gene gyrA foi realizada através de sequenciamento. Campylobacter foi isolado a partir de 100% das amostras avaliadas, sendo 68,75% correspondente à C. jejuni e 31,25% à C. coli. No teste de difusão em disco, 100% das cepas foram resistentes à ciprofloxacina e 56,25% das cepas foram resistentes à enrofloxacina. No teste de diluição em ágar, todas as cepas foram resistentes à ciprofloxacina apresentando CIM variando de ≥ 16-64μg/mL, e resistência ou resistência intermediaria à enrofloxacina foi detectada em 42,50% (CIM ≥ 4-32μg/mL) e 38,75% (CIM = 2μg/mL) das cepas, respectivamente. A mutação Tre-86-Ile, foi observada em 100% das cepas analisadas. Além dessa mutação, foram observadas outras mutações não silenciosas (Val-73-Glu, Ser-114-Leu, Val-88-Asp, Ala-75-Asp, Ser-119-Gli, Arg-79-Lis) e mutações silenciosas (His-81-His, Ser-119-Ser, Ala-120-Ala, Fen-99-Fen, Ala-122-Ala, Gli-74-Gli, Ile-77-Ile, Ala-91-Ala, Leu-92-Leu, Val-93-Val, Ile-106-Ile, Tre-107-Tre, Gli-113-Gli, Ile-115-Ile, Gli-110-Gli). A observação de que cepas sensíveis à enrofloxacina pelos testes fenotípicos apresentavam a substituição Tre-86 para Ile sugere que outros mecanismos podem contribuir para a resistência à enrofloxacina em Campylobacter. Abstract Studies have shown that resistance to quinolones in Campylobacter strains is related with Threonine-86-Isoleucine mutation. In order to investigate the presence of this mutation in sensitive and resistant Campylobacter strains to ciprofloxacin and enrofloxacin, the cecal contents of 80 broilers from organic raising chickens, slaughtered under State Inspection Service (S.I.S) of the State of Rio de Janeiro, were collected and tested for the presence of Campylobacter. The determination of ciprofloxacin and enrofloxacin susceptibility was done by disk diffusion and agar dilution methods for determining the Minimum Inhibitory Concentration (MIC). The detection of mutation in Quinolone Resistance Determinant Region (QRDR) in gyrA gene was done by sequencing. Campylobacter was isolated from 100% of the samples, being 68.75% C. jejuni and 31.25% C. coli. By the disk diffusion method, resistance to ciprofloxacin was observed in all isolates and 56.25% of the strains were resistant to enrofloxacin. By agar dilution method, all strains were resistant to ciprofloxacin (MIC ≥ 16μg/mL to ≥ 64μg/mL) and full and intermediate resistance to enrofloxacin was detected in 42.50% (MIC ≥ 4-32μg/mL) and 38.75% (MIC =2μg/mL) of the strains, respectively. Mutation Thr-86-Ile was observed in 100% of the isolates investigated. In addition to this mutation, others no silent mutations (Val-73-Glu, Ser-114-Leu, Val-88-Asp, Ala-75-Asp, Gly-119-Ser, Arg-79-Lys) and silent mutations (His-81-His, Ser-119-Ser, Ala-120-Ala, Phe-99-Phe, Ala-122-Ala, Gly-74-Gly, Ile-77-Ile, Ala-91-Ala, Leu-92-Leu, Val-93-Val, Ile-106-Ile, Thr-107-Thr, Gly-113-Gly, Ile-115-Ile, Gly-110-Gly) were detected. All the enrofloxacin-sensitive strains by the phenotypic methods had the Thr-86 to Ile substitution, which suggests other mechanisms contributing to enrofloxacin resistance in Campylobacter.

The aim of this study was to investigate the effect of ultraviolet (UV)-C treatment on the decrease of the inoculated Staphylococcus aureus population in precooked shredded bullfrog meat. The precooked meat was inoculated with 8 log cfu/g of S. aureus. The packaged bullfrog's back meat was then exposed to low (0.65 mW/s/cm2), medium (1.04 mW/s/cm2) and high (1.68 mW/s/cm2) UV-C intensities over different time intervals (60, 100 and 140 s). A reduction of 3 log cfu/g was observed in all treatments when compared with the inoculated but nonirradiated treatment (T0). All the UV-C treatments of bullfrog's back meat used in this study reduced the S. aureus count (P

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.

Physicochemical and microbiological changes in yogurts determine their storage and shelf life. Thus, monitoring yogurt quality is essential for consumer acceptance and food safety. However, traditional techniques of yogurt quality analysis are food-destructive, environment polluting, costly, and time-consuming. On the other hand, nondestructive techniques only measure a single quality property, not expressing the yogurt overall quality. In this study, predictive models validated by bootstrapping and cross-validation methods demonstrate the biogenic amine index (BAI) as a nondestructive monitoring system of overall quality during storage. The optical parameter was a strong nondestructive predictor of the BAI for both cow’s milk yogurt, CY (Rv = 0.944; p = 0.007), and goat’s milk yogurt, GY (Rv = 0.909; p = 0.009). For CY, the reduction in the overall acceptability during storage was a strong predictor of the BA index (Rv = 0.869; p

The aim of this Research Communication was to investigate the changes in physicochemical, colour, apparent viscosity and texture properties in low-fat goat milk yogurts prepared with cupuassu pulp by the addition of inulin (SI), maltodextrin (SM), whey protein (SW) and skim milk powder (SP). Three batches of each cupuassu goat milk yogurt were prepared and analysed on the 1st day of storage by pH, proximate composition, colour, apparent viscosity, and texture. In comparison to yogurts from whole (W) or skimmed milk (S), all of the fat replacers improved the physicochemical properties (P < 0·05). The addition of the carbohydrates (inulin and maltodextrin) and proteins (whey protein and skim milk powder) also influenced the colour of the low-fat cupuassu goat milk yogurt (P < 0·05). All fat replacer treatments (SI, SM, SW and SP) presented a higher (P < 0·05) apparent viscosity than W and S yogurts. However, only the addition of skim milk powder increased the texture parameters (firmness and consistency) (P < 0·05). These results suggest that skim milk powder can be used to improve the texture properties of low-fat cupuassu goat milk. Furthermore, inulin, maltodextrin, and whey protein can potentially be applied in the goat dairy industry to increase the viscosity of yogurts.

The aim of this study was to determine the potential for waste extracts from the pequi (Caryocar brasiliense) and juçara (Euterpe edulis) to reduce oxidatiove processes in antibiotic-free broiler meat. The use of natural antioxidants extracted from fruit-processing wastes has been neglected. Although these residues contain high amounts of these bioactive compounds, they are often discarded by industry. Meat samples were exposed previously submitted to UV-C radiation at 1.161 mW / cm2 for 10 minutes to accelerate the rancidity process. Pequi and juçara waste extracts were obtained by microwave-assisted extraction (MAE). A total of four conditions were tested using antibiotic-free broiler thighs and drumstick meat: BN-with no antioxidant (negative control), BP-with BHT (Butylated hydroxytoluene) (positive control), BE-with juçara extract, BC-with pequi extract. The color, pH, lipid and protein oxidation (days 0, 2, 4, 6, 8 and 10), antioxidant contents and activity (days 0 and 10), and proximal composition and fatty acid profile (day 0) were tested, followed by principal component analysis (PCA). Pequi waste extract presented the highest antioxidant content and activity. BE and BC treatments presented the highest total phenolic (TPC) and flavonoid (TFC) content, and BE presented the highest total monomeric anthocyanin content (TAC). TFC increased during storage in all treatments. The waste extracts of C. brasiliense presented the highest antioxidant activity against lipid oxidation in the antibiotic-free broiler meat. Moreover, both extracts presented high antioxidant activity against protein oxidation. Although the pequi peel extract had a better effect in terms of suppressing both types of oxidation, either this extract or the jussara waste extract could be used as a technological strategy to reduce the oxidative processes in antibiotic-free broiler meat for the poultry industry. Thus, waste extracts can be a potential technology to reduce the oxidative processes in antibiotic-free broiler meat.

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 (CCβ), 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 CCβ 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.

Poultry are considered to be the main reservoir of Campylobacter spp. 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 Campylobacter is 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 Campylobacter strains previously isolated from broiler carcasses and feces of laying hens. Thirty-eight strains of C. jejuni and 19 C. coli strains (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 in Campylobacter strains 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. jejuni and C. coli.

Cupuassu is an acidic fruit that has a characteristic aroma, flavor, and texture; its fiber-rich pulp can provide a different consistency than other fruit pulps. Goat milk is an excellent source of amino acids, fatty acids, and minerals, and is widely used for processing fermented milks, such as yogurt. However, compared with cow milk yogurts, it is difficult to make goat milk yogurts with a good consistency. Therefore, it is necessary to use certain technological strategies. This study was carried out to investigate the possibility of adding cupuassu pulp, probiotic (Lactobacillus acidophilus LA-5), and prebiotic (inulin) to improve the texture of goat milk yogurt. A total of 6 treatments were performed: natural (N), probiotic (Pro), prebiotic (Pre), synbiotic (S), cupuassu (C), and probiotic with cupuassu (PC). The viability of probiotic in yogurts (Pro, S, and PC) was evaluated. In addition, instrumental analyses (pH, color, apparent viscosity, and texture) were performed to evaluate the influence of these different ingredients on goat milk yogurts. The probiotic bacteria remained viable (≥7 log cfu·mL(-1)) throughout the 28d of refrigerated storage, which exceeded the minimum count required to confer probiotic physiological benefits. The pH levels of the yogurts inoculated with L. acidophilus (Pro, S, and PC) were lower than others yogurts (N, Pre, and C). However, all yogurt samples underwent gradual decreases in pH until 7 to 14d of storage. The lightness (L*) was affected initially by addition of all ingredients (cupuassu pulp, probiotic, and prebiotic). The addition of cupuassu pulp (C and PC) increased the L* during the period of storage. Apparent viscosity and firmness decreased in the PC yogurt. The consistency was highest in the yogurts with added prebiotic (Pre and S) than the other yogurts (N, Pro, C, and PC) at the end of the storage period (d 28). The cohesiveness remained constant in all yogurts (N, Pro, Pre, S, C, and PC). Based on the results obtained from the current study, it was concluded that cupuassu pulp addition improves the texture of goat milk yogurts. Therefore, this pulp could be an important technological strategy for the dairy goat industry.

The Euterpe edulis (Juçara) is native to Brazil, which berries and wastes present high antioxidant content. Therefore, in this study, microwave-assisted extraction (MAE) was investigated for antioxidant compounds extraction from E. edulis waste and maximized antioxidant activities using response surface methodology coupled with a central composite design. Three factors were observed: microwave power (400/500/600 W), exposition time (30/60/90 sec) and ethanol concentration solvent (40/60/80%). The extracts were characterized by determination of total phenolic (TPC), flavonoids (TFC), monomeric anthocyanins (TAC), tannins content (TTC), and in vitro antioxidant assay (AA%). The yield of TPC, TFC, TAC, and TTC varied at 595.43-2171.34 mg GAE.100 g DM-1, 137.36-251.24 mg QE.100 g DM-1, 179.32-354.38 mg C-3-GE.100 g DM-1 and 0.23-1.00 µg TAE.100 g DM-1, respectively. The optimal MAE parameters for TPC was microwave power 668.18 W, exposition time 110.45 s and aqueous ethanol concentration 93.64%, for TFC same parameters observed; though for TAC the different parameters were 532.28 W, and for TTC 9.55 s. However, for antioxidant activity, the parameters were 668.18 W, 110.45 s time and 64.41% of aqueous ethanol solvent. Therefore, this methodology was successfully applied for optimal extraction of total phenolics, flavonoids, monomeric anthocyanins and tannins from juçara waste and obtain optimal antioxidant activity.