resumo O combate à Covid-19 impulsionou enormes avanços na pesquisa científica, mas também a veiculação de informações de baixa qualidade, com pouca ou nenhuma fundamentação científica. Infelizmente, os alimentos aparecem de forma recorrente nos meios de comunicação acessíveis ao grande público como possíveis disseminadores da doença, trazendo inquietudes para a população, órgãos reguladores e cadeia produtiva de alimentos. Neste artigo, preparado com base na literatura científica disponível, são respondidas as seguintes questões: Os alimentos ou suas embalagens são transmissores do vírus Sars-CoV-2? Os alimentos podem causar Covid-19? O setor de alimentação e a indústria de alimentos são responsáveis pela propagação do Sars-CoV-2? Quais as medidas preventivas que os consumidores podem adotar para proteger sua saúde?

abstract The struggle against Covid-19 has driven enormous advances in scientific research, but also the dissemination of low-quality information, with little or no scientific basis. Unfortunately, food appears recurringly in the mainstream media as a possible disseminator of the disease, raising concerns in consumers, regulatory agencies and the food production chain. In this article, based on available scientific literature, the following questions are answered: Are foods or food packaging transmitters of the Sars-CoV-2 virus? Can foods cause Covid-19? Are foods or the food industry responsible for the spread of Sars-CoV-2? What preventive measures can the consumers take to protect their health?

Abstract Phenolic compounds (PC) have presented antioxidant potential as well as antimicrobial action against several bacteria. This study aimed to extract PC from grumixama (Eugenia brasiliensis Lam.) pulp using solid phase extraction (SPE), then quantify the PC by Folin-Ciocalteu assay, and to evaluate the antioxidant activity (AA) from PC by DPPH, ABTS and FRAP methods as well as its antimicrobial activity by plate diffusion assay (PDA) and Minimal Inhibitory Concentration (MIC) assays. Additionally, the centesimal composition of the fruit and its mineral content by Total Reflection X-Ray Fluorescence Spectroscopy were determined. The fruit is a good source of PC which presented a higher contribution on AA from pulp than NPHRC. Calcium was the trace element in highest concentration in the pulp, followed by iron. PC from grumixama inhibited the growth of Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa but not Escherichia coli and Listeria monocytogenes in the PDA. PC showed antimicrobial activity against the five microorganisms tested in the MIC assay, in which S. aureus and B. cereus were the most sensitive. This study highlights the antioxidant and antimicrobial potential of Eugenia brasiliensis Lam. as natural agent in the development of functional foods and nutraceuticals.

Abstract The aim of this study was to assess the anti-quorum sensing activity of phenolic extracts from grumixama (Eugenia brasiliensis), also known as Brazilian cherry, in concentrations that did not interfere with bacterial growth. The pulp phenolic compounds were extracted by using solid phage extraction in a mini-collumn C18 and quantified by spectrophotometry. The anti-quorum sensing activity was evaluated by testing the inhibition of violacein production in Chromobacterium violaceum and by evaluating the swarming motility in Aeromonas hydrophila and Serratia marcescens, both phenotypes regulated by quorum sensing. The phenolic extract strongly inhibited the production of violacein in C. violaceum, reducing its production in comparison with a control with no extract. No inhibition of growth was observed at the concentrations tested for quorum sensing inhibition. Confirming the quorum sensing inhibition phenotype, the extract was also able to inhibit swarming motility in S. marcescens and in A. hydrophila, although in the later the effect was marginal. Overall, these results indicate that phenolic extract from E. brasiliensis presents quorum sensing inhibitory activity most likely due to the presence of fruit phenolics which have been implicated as quorum sensing inhibitors in Gram negative bacteria.

A água de coco é muito popular em todo o mundo, principalmente em virtude das suas características sensoriais agradáveis, do valor nutricional e das baixas calorias. No entanto, a água de coco é um produto altamente perecível em função da presença de enzimas - tais como peroxidase e polifenoloxidase, que causam alterações indesejáveis na cor - e também em função da sua susceptibilidade à deterioração microbiana. O uso de aditivos químicos tem sido adotado pela indústria com a intenção de aumentar a vida de prateleira do produto. Neste estudo, a eficiência dos conservantes sorbato de potássio e metabissulfito de sódio foi avaliada considerando-se a estabilidade da água de coco carbonatada por meio do delineamento composto central rotacional (DCCR), variando as concentrações de sorbato de potássio entre 0 e 500 mg.L-1, e de metabissulfito de sódio entre 0 e 100 mg.L-1. Foram realizadas avaliações físico-químicas de volume de carbonatação, pH, sólidos solúveis totais, oxigênio e dióxido de carbono dissolvidos, acidez, ácido ascórbico, atividade de polifenoloxidase e peroxidase, cor e atributos de turbidez. As análises microbiológicas realizadas foram de contagem total de aeróbios, bem como de enumeração de bolores e leveduras. Observou-se que as concentrações de 375 mg.L-1 de sorbato de potássio e 75 mg.L-1 de metabissulfito de sódio apresentaram os melhores atributos de qualidade, no que diz respeito a pequenas alterações na acidez e à cor da água de coco, desde que a matéria-prima apresentasse contaminação microbiológica baixa.

Coconut water is popular worldwide, mainly because of its pleasant sensory characteristics, nutritional value and low calorie density. However, coconut water is a highly perishable product due to the presence of enzymes such as peroxidase and polyphenoloxidase, which cause undesirable changes in colour, and also because of its susceptibility to microbial spoilage. The use of chemical additives has been adopted by the industry with the intent of increasing product shelf life. In this study, the efficiency of the preservatives potassium sorbate and sodium metabisulphite was assessed using a Central Composite Rotational Design (CCRD) to determine the stability of carbonated coconut water, varying the concentrations of potassium sorbate from 0 to 500 mg.L-1, and of sodium metabisulphite from 0 to 100 mg.L-1. The chemical evaluations included carbonation volume, pH, soluble solids, dissolved oxygen and carbon dioxide, acidity, ascorbic acid, polyphenoloxidase and peroxidase activities, colour and turbidity attributes. The microbiological evaluations considered the total aerobic plate count and the enumeration of yeasts and moulds. It was observed that concentrations of 375 mg.L-1 of potassium sorbate and 75 mg.L-1 of sodium metabisulphite gave the best quality attributes with respect to minor changes in acidity and colour of the coconut water, providing that the raw material had low microbiological contamination.

OBJETIVO: A presença de Listeria monocytogenes, Salmonella sp. e Klebsiella sp. em dietas enterais e em ambientes, utensílios e equipamentos de preparo de alimentos em serviço de alimentação hospitalar, foi o objetivo desta pesquisa. MÉTODOS: A contaminação de ambientes, utensílios e equipamentos de preparo de alimentos em serviço de alimentação hospitalar por Listeria monocytogenes, Salmonella sp. e Klebsiella sp. foi avaliada em 50 amostras coletadas pela técnica de swab. Quatro amostras de dietas enterais também foram analisadas. Colônias típicas de bactérias do gênero Listeria foram isoladas de dieta enteral em ágar Oxford e a identificação da espécie L. monocytogenes foi feita por testes bioquímicos e imunológicos. RESULTADOS: A presença de Salmonella foi detectada em dieta enteral e identificada como S. rissen por sorologia. Pela relevância como agente causador de infecções hospitalares, bactérias do gênero Klebsiella foram pesquisadas e isoladas em ágar seletivo MacConkey-inositol-carbenicilina. K. pneumoniae foi encontrada em equipamento e utensílio e K. oxytoca em ambiente, equipamento e dieta enteral. Os isolados de L. monocytogenes apresentaram resistência apenas ao antibiótico cefoxitina e os do gênero Klebsiella foram resistentes a ampicilina e amoxilina. S. rissen foi sensível aos 13 antibióticos avaliados. CONCLUSÃO: A contaminação de 11% das amostras analisadas com pelo menos um dos patógenos, alerta para a necessidade de implantação de um rigoroso sistema de controle de qualidade nas áreas de manipulação dos alimentos, a fim de aumentar a segurança alimentar dos pacientes hospitalizados.

OBJECTIVE: The purpose of the research was to investigate the presence of Listeria, Salmonella and Klebsiella on samples of enteral diets and utensils, surfaces and equipments involved in food preparation in a hospital food service. METHODS: Fifty samples collected from utensils, surfaces and equipment used for food preparation in a hospital food service, and four samples collected from enteral diets were tested for bacteria of genera Listeria, Salmonella and Klebsiella. Typical colonies of bacteria of the genus Listeria from enteral diet were isolated in Oxford agar and contamination by L. monocytogenes was confirmed by immunoanalysis. RESULTS: L. monocytogenes, S. rissen and Klebsiella were isolated from enteral diet. For their relevance as agents of hospital infections, bacteria of the genus Klebsiella were evaluated. K. pneumoniae were found in equipment and utensil, and K. oxytoca were found in environment, equipment and enteral diet samples. L. monocytogenes showed resistance to cefoxitin and all Klebsiella were resistant to amoxacillin and ampicillin. S. rissen showed susceptibility to all 13 antibiotics tested. CONCLUSION: The study showed that 11% of the analyzed samples were contaminated with, at least, one of the investigated pathogens. Such results reiterate the need for awareness and knowledge of effective hygienic procedures in the hospital food manipulation areas, in order to ensure patients' safety.