Origanum vulgare L. (OVEO) essential oil has been considered a candidate antimicrobial for use in food conservation systems. However, studies on the influence of concomitant variations of different food components or physicochemical parameters on the antibacterial properties of OVEO are scarce. This study assessed the influence of concomitant variations in amounts of proteins - PTN (4.0, 6.0 or 8.0 g/100 mL) and lipids - LIP (3.75, 5.0 or 6.25 g/100 mL) and pH values (5.0, 5.5 or 6.0) in cultivation medium on the inhibitory effects of OVEO against Escherichia coli (EC) and Salmonella Typhimurium (ST). Lowest minimum inhibitory concentration values of OVEO against EC and ST were observed in media with the highest LIP amounts regardless the PTN amount and pH value. In absorbance based microtiter plate assay (MPA), for both EC and ST, OVEO caused the lowest Grmax values in medium containing the highest LIP and PTN amounts and lowest pH value. Highest Grmax values for EC and ST were observed in medium containing the lowest LIP and PTN amount and highest pH value. Grmax values estimated from viable counts of EC and ST in tested media with OVEO confirmed bacterial growth behavior similar to that observed in MPA. Overall, the LIP amount in media was as the most influential factor to enhance the antibacterial effects of OVEO. These results indicate that the concomitant influence of LIP and PTN amounts and pH values on the antibacterial effects of OVEO should be considered for optimizing its antimicrobial efficacy in foods.

RESUMO O presente trabalho objetivou processar, caracterizar e utilizar a polpa e a farinha de resíduo de seriguela (Spondias purpurea L.) (FRS) no processamento de biscoitos, avaliando sua qualidade nutricional, microbiológica e aceitação sensorial. A FRS foi elaborada e caracterizada quanto às suas características físico-químicas. Os biscoitos foram elaborados a partir da FRS nas concentrações de 0; 10; 20 e 30% e submetidos às análises de composição centesimal, acidez, pH, ácido ascórbico, atividade de água, além da determinação do rendimento e dos custos. A análise microbiológica dos biscoitos foi executada previamente à análise sensorial, que foi realizada por 100 potenciais consumidores. A FRS apresentou elevados teores de vitamina C (57,99 mg/100 g), fibras (12,82%), carboidratos (71,77%) e valor calórico (313,21 Kcal/100 g). À medida que houve adição de resíduo, houve o aumento do teor de fibras, minerais e vitamina C nos biscoitos. Os biscoitos apresentaram notas sensoriais entre 6 e 7, de uma escala hedônica de 9 pontos, e o biscoito contendo 10% da farinha de resíduo de seriguela foi o mais aceito, com intenção de compra e preferência semelhantes aos biscoitos-controle, que foram elaborados com 100% de farinha de trigo. O aproveitamento de resíduos da seriguela na elaboração de biscoitos pode ser uma alternativa viável de alto valor nutricional e de baixo custo dos ingredientes utilizados no processamento desses produtos alimentícios, além de ser importante sob o ponto de vista ambiental.

ABSTRACT This study aimed to process, characterize and use seriguela fruit residue pulp and flour (Spondias purpurea L.) (SFR) in the processing of cookies, evaluating nutritional and microbiological quality and sensory acceptance. SFR was prepared and characterized as to its physical and chemical characteristics. Cookies made with SFR at concentrations of 0, 10, 20 and 30% were submitted to analyses of chemical composition, acidity, pH, ascorbic acid, water activity, in addition to yield and costs. Microbiological analysis of cookies was performed previously to sensory analysis, which was performed by 100 potential consumers. SFR showed high levels of Vitamin C (57.99 mg / 100 g), fiber (12.82%), carbohydrate (71.77%) and energy density (313.21 Kcal/100 g). As SFR was added, there was an increase in the content of fibers, minerals and vitamin C. Cookies showed sensory scores between 6 and 7 of a 9-point hedonic scale; however, cookie containing 10% of seriguela fruit residue flour was the most accepted, with purchase intent and preference similar to control cookies, which were made with 100% wheat flour. The use of seriguela fruit residue in the production of cookies can be a viable option to increase the nutritional value and reduce the cost of ingredients used in the processing of food products, in addition to being important from the environmental point of view.

This study assessed the capacity of adhesion, the detachment kinetic and the biofilm formation by Staphylococcus aureus isolated from food services on stainless steel and polypropylene surfaces (2 x 2 cm) when cultivated in a meat-based broth at 28 and 7 ºC. It was also to study the efficacy of the sanitizers sodium hypochlorite (250 mg/L) and peracetic acid (30 mg/L) in inactivating the bacterial cells in the preformed biofilm. S. aureus strains adhered in high numbers regardless the assayed surface kind and incubation temperature over 72 h. Cells detachment of surfaces revealed high persistence over the incubation period. Number of cells needed for biofilm formation was noted at all experimental systems already after 3 days. Peracetic acid and sodium hypochlorite were not efficient in completely removing the cells of S. aureus adhered on polypropylene and stainless steel surfaces. From these results, the assayed strains revealed high capacity to adhere and form biofilm on polypropylene and stainless steel surfaces under different growth conditions. Moreover, the cells in biofilm matrix were resistant for total removal when submitted to the exposure to sanitizers.

O objetivo deste trabalho foi avaliar a produção de um tipo de farinha de subprodutos (cefalotórax), obtidos da indústria de beneficiamento do camarão (Litopenaeus vannamei), e realizar uma análise sensorial de produtos formulados com a farinha. Foram feitas análises físico-químicas e microbiológicas do cefalotórax fresco e da farinha formulada, assim como a determinação do teor de colesterol dessa farinha e a avaliação sensorial de uma sopa e um pastel feitos com ela. Pelas análises microbiológicas, nenhum microrganismo patogênico foi encontrado nas amostras. As análises físico-químicas da farinha mostraram elevados teores de proteínas (50,05%) e minerais (20,97%). A farinha de cefalotórax de camarão apresentou elevado teor de colesterol. A avaliação sensorial indicou boa aceitação dos produtos, com índice de aceitabilidade satisfatório (81% para a sopa e 83% para o pastel), o que indica que o cefalotórax de camarão, na forma de farinha, tem potencial para o desenvolvimento de novos produtos.

The objective of this work was to evaluate the production of flour using by-products (cephalothorax) obtained from the shrimp (Litopenaeus vannamei) industry, and to perform a sensory analysis of shrimp flour-based products. Physicochemical and microbiological analyses on fresh cephalothorax and on manufactured flour were performed, as well as the determination of cholesterol content of this flour, and the sensorial evaluation of soup and pastry made with this flour. By the microbiological analyses, no pathogenic microorganism was detected in the samples. Physicochemical analyses of flour showed high levels of protein (50.05%) and minerals (20.97%). Shrimp cephalothorax flour showed high levels of cholesterol. The sensory evaluation indicated a good acceptance of the products, with satisfactory acceptability index (81% for soup, and 83% for pastry), which indicates that shrimp cephalothorax in the form of flour has a potential for developing new products.

Este estudo teve como objetivo avaliar o efeito de diferentes meios de crescimento [caldo BHI, caldo BHI adicionado de glucose (10 g/100 mL) e caldo BHI adicionado de NaCl (5 g/100 mL)] e temperaturas de incubação (28 e 37 ºC) sobre a adesão, separação e formação de biofilme sobre superfícies (2 x 2 cm) de polipropileno e aço inoxidável durante longo tempo de incubação (24-72 h) por parte de cepas de Staphylococcus aureus (S3, S58 e S54) isoladas de plantas de processamento de alimentos. Também foi avaliada a eficácia dos sanitizantes hipoclorito de sódio (250 mg/mL) e ácido peracético (30 mg/mL) na redução do número de células bacterianas viáveis presentes em um biofilme pré-formado. As cepas de S. aureus aderiram em número mais elevado quando incubadas em caldo BHI em ambos os tipos de superfícies e temperaturas de incubação testadas. A separação das células das superfícies revelou alta persistência ao longo do período de incubação. Número de células necessário para a formação do biofilme foi detectado depois de três dias de incubação em todos os sistemas experimentais. O ácido peracético e o hipoclorito de sódio não foram eficientes em remover completamente a células de S. aureus aderidas sobre as superfícies de polipropileno e aço inoxidável. Os resultados obtidos revelaram alta capacidade das cepas ensaiadas em aderir e formar biofilme sobre superfícies de polipropileno e aço inoxidável sobre diferentes condições de crescimento e que as células na matriz do biofilme apresentaram-se resistentes à total remoção quando expostas aos sanitizantes hipoclorito de sódio e ácido peracético.

This study assessed the effect of different growth media [BHI broth, BHI broth plus glucose (10 g/100 mL) and BHI broth plus NaCl (5 g/100 mL)] and incubation temperatures (28 or 37 ºC) on the adherence, detachment and biofilm formation on polypropylene and stainless steel surfaces (2 x 2 cm coupons) for a prolonged period (24-72 h) by some strains of Staphylococcus aureus (S3, S28 and S54) from food processing plants. The efficacy of the sanitizers sodium hypochlorite (250 mg/mL) and peracetic acid (30 mg/mL) in reducing the number of viable bacterial cells in a preformed biofilm was also evaluated. S. aureus strains adhered in highest numbers in BHI broth, regardless of the type of surface or incubation temperature. Cell detachment from surfaces revealed high persistence over the incubation period. The number of cells needed for biofilm formation was noted in all experimental systems after 3 days. Peracetic acid and sodium hypochlorite were not efficient in completely removing the cells of S. aureus adhered onto polypropylene and stainless steel surfaces. From these results, the assayed strains revealed high capacities to adhere and form biofilms on polypropylene and stainless steel surfaces under the different growth conditions, and the cells in biofilm matrixes were resistant to total removal when exposed to the sanitizers sodium hypochlorite and peracetic acid.

Este estudo teve como objetivo avaliar o potencial de utilização da carne de ovinos de descarte na elaboração de mortadelas. Três formulações de mortadela foram desenvolvidas, com 90, 80 e 70% de carne ovina, adicionadas de 10, 20 e 30% de gordura suína. Os resultados demonstraram que as três formulações de mortadela atenderam aos parâmetros microbiológicos preconizados pela legislação brasileira, sendo, portanto, seguros para o consumo humano. Para os parâmetros cinzas, amido, cloretos, pH e atividade de água não houve diferença estatística entre as formulações (P>0,05). Os valores obtidos na análise de umidade diferiram estatisticamente entre os tratamentos (P<0,05), aumentando os valores médios, à medida que foram aumentados os percentuais de carne adicionados, ficando a formulação com 90% de carne fora dos padrões recomendados pela legislação brasileira. A mortadela elaborada com 90% de carne obteve maiores percentuais nas análises de estabilidade de emulsão e capacidade de retenção de água. A formulação elaborada com 90% de carne se diferenciou das demais estatisticamente na análise sensorial, sendo a ela atribuídos escores menores para os atributos de textura e avaliação global. Na avaliação da intenção de compra, os avaliadores comentaram que comprariam os produtos independente das formulações. Os resultados demonstram que a carne de ovinos de descarte é uma opção viável na elaboração de mortadela, uma vez que resulta em produtos com elevado grau de aceitação e qualidade nutricional, agregando valor aos cortes de ovinos.

The aim of this study was to evaluate the potential use of spent lamb meat in the preparation of mortadella. Three formulations of mortadella were developed, using 90, 80 and 70% of lamb meat, each with 10, 20 and 30% of pork fat, respectively. The results showed that the proposed formulations met the microbiological parameters recommended by the Brazilian legislation, being, therefore, a safe meat product for human consumption. The parameters of ashes, starch, sodium chloride, pH and water activity showed no significant difference among the formulations (P>0.05). The moisture contents differed significantly from one sample to the other (P<0.05). An increase in the amount of lamb meat in the mortadella formulation resulted in an increase in moisture; this made the formulation with 90% meat improper, according to the standards recommended by the Brazilian legislation. The mortadella with 90 % meat had the highest percentages of emulsion stability and water holding capacity. The sensory evaluation showed that the formulation with 90% lamb meat presented the lowest scores of texture and overall acceptance. However, the evaluators commented that they would buy any of the products regardless of the formulation. The results show that the use of spent lamb meat is a viable option for the preparation of mortadella, as the resulting products have been widely accepted. In addition, it also gives spent lamb carcasses more commercial value.

This study assessed the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare L. essential oil and lactic acid against Staphylococcus aureus by the determination of Fractional Inhibitory Concentration (FIC) index and cell viability in meat broth and meat model. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the oil was 0.6 and 1.25 µL.mL-1, respectively. Lactic acid showed MIC and MBC of 2.5 and 5µL.mL-1, respectively. FIC indices of the combined application of the oil and lactic acid were 0.5 showing a synergic interaction. The essential oil and lactic acid showed similar (p>0.05) anti-S. aureus effect in meat broth over 96 h of exposure. Treatment with essential oil or lactic acid presented a smaller anti-staphylococcal effect in meat in comparison to meat broth. No significant difference (p>0.05) was found for the microbial counts in meat treated with each antimicrobial alone or in mixture. These results could arise as an interesting approach for the improvement of food preservation using more natural procedures, considering the current demand of consumer and sensory quality of foods.

Este estudo avaliou a ocorrência de um efeito inibitório potencializado quando da aplicação combinada do óleo essencial de O. vulgare e ácido acético sobre Staphylococcus aureus através da determinação Concentração Inibitória Fracional (FIC) e de ensaios de tempo de morte em caldo nutriente, caldo base carne e em um modelo alimentar (pedaços de carne). O ácido acético mostrou um valor de CIM e CBM de 0,6 e 1,25 µL.mL-1, respectivamente. Estudos prévios encontraram valores de CIM e CBM para o óleo essencial de O. vulgare sobre as cepas teste de S. aureus de 1,25 e 1,5 µL.mL-1, respectivamente. Valores de índices de CIF da mistura do óleo essencial e ácido acético na concentração de CIM x ½ foram £ 1,0 caracterizando uma interação de adição. Nenhum efeito sinérgico foi encontrado nos ensaios de tempo de morte. O efeito anti-estafilocócico dos antimicrobianos isolados ou em combinação (CIM x ½) foi menor quando aplicado em carne em comparação a sua adição em caldo nutriente e caldo carne. A efetiva combinação de óleos essenciais e outros agentes preservativos pode ser reconhecida como uma alternativa promissora para a indústria de alimentos, podendo viabilizando a diminuição de doses de antimicrobianos aplicadas para inibir o crescimento microbiano em alimentos.

This study evaluated the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare L. essential oil and acetic acid against Staphylococcus aureus by the determination of Fractional Inhibitory Concentration (FIC) index and kill-time assay in nutrient broth, meat broth and in a food model (meat pieces). Acetic acid showed MIC and MFC of 0.6 and 1.25 µL.mL-1, respectively. For O. vulgare essential oil MIC and MBC were 1.25 and 2.5 µL.mL-1, respectively. FIC indexes of the mixture of essential oil and acetic acid at MIC x ½ were £ 1.0, showing an additive effect. No synergy was found at kill-time study. Anti-staphylococcal effect of the antimicrobials alone or in mixture (MIC x ½) was lower in meat than in nutrient and meat broths. The effective combination of essential oils and organic acids could appear as an attractive alternative for the food industry, as the doses to inhibit the microbial growth in foods can be lowered.