Fruit bioactive compounds: Effect on lactic acid bacteria and on intestinal microbiota.

The benefits of bioactive compounds to human health have been highly explored in recent years; they are widely distributed in nature, mainly in fruits. In this review, the effect of the main fruit bioactive compounds (FBC) on lactic acid bacteria (LAB) and on gut microbiota composition was discussed. The fruit dietary fibers, phenolic compounds, fatty acids, carotenoids, and vitamins have important health benefits. Furthermore, they can interact with LAB and modulate the human intestinal microbiota, which favor the diversity of beneficial bacterial groups, thus providing several benefits to human health, such as reducing weight gain, improving the mucosal barrier function of gastrointestinal (GI) tract against pathogens, decreasing chronic inflammation and incidence of diseases, such as cardiovascular ones, diabetes, hypertension and chronic diseases. Additionally, FBC are able to change the Firmicutes/Bacteroidetes ratio and inhibit the putrefactive bacteria in the gut. Due to the complex composition of human gut microbiota and variations among individuals, additional research must be carried out to elucidate the mechanism of interaction between the bioactive compounds and the human microbiota.

Modulation of volatile release and antimicrobial properties of pink pepper essential oil by microencapsulation in single- and double-layer structured matrices.

The bioactivity of essential oils applied in foods to act as natural preservatives can be reduced due to interactions with other components of the food matrix. Microencapsulation can help to increase the functionality of these compounds. In addition, the electrostatic interaction between proteins and polysaccharides can result in double-layered encapsulating structures, ensuring greater protection to essential oils than using only protein as surface active agent. In this work, pink pepper essential oil was microencapsulated by spray drying of single-layer emulsions, stabilized by soy protein isolate (SPI), and of double-layer emulsions, stabilized by soy protein isolate/high methoxyl pectin (SPI/HMP). Pink pepper essential oil showed predominance of α-pinene, ß-pinene, ß-mircene, δ-3-carene, d-limonene, and germacrene D. Compared to SPI microcapsules, SPI/HMP microcapsules better preserved the total volatile content identified in pure oil, showed less water adsorption during storage at relative humidity ≥75% and improved antimicrobial properties. When stored for 20 days (25 °C/RH = 52.8%), both microcapsules allowed more gradual release of volatiles compared with non-encapsulated oil. Microencapsulation by spray drying did not have negative effects on the antioxidant activity of the encapsulated oil, as the microcapsules showed similar results to the non-encapsulated oil, around 11 µg Trolox/mg of oil. After storage, however, the non-encapsulated oil showed greater losses of its antioxidant activity due to higher rates of volatile release. In the in vitro antimicrobial activity assay, both microcapsules inhibited growth of Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes and Listeria innocua, although no inhibition was observed against Gram-negative bacteria. When added in milk, both microcapsules reduced bacterial growth, whereas non-encapsulated oil showed no satisfactory inhibition. Faster reduction of microbial growth in milk was observed for SPI/HMP microcapsules. Inhibition results were better for skim milk than for whole milk, suggesting that the interaction of essential oil with other lipids present in milk decreased its bioactivity. Microencapsulation positively affected the functionality of pink pepper essential oil, highlighting its potential for application as a natural preservative in food products.

Effect of the pre-treatment and the drying process on the phenolic composition of raisins produced with a seedless Brazilian grape cultivar.

The grape is an important fruit regarding economic and health benefit parameters, because of its large consumption around the world and their bioactive phenolic compounds. The drying process of BRS Morena grapes, whether pre-treated or not with olive oil for producing raisins, resulted in qualitative and quantitative changes in their phenolic composition (anthocyanins, flavonols, stilbenes, hydroxycinammic acid derivatives, flavan-3-ols and proanthocyanidins). The raisins with the pre-treatment preserved more anthocyanins and proanthocyanidins than the raisins not pre-treated. Moreover, the total dehydration time accelerated by approximately 40% in the raisins pre-treated. Therefore, the production of raisins of BRS Morena grapes pre-treated with olive oil as a natural surfactant constitutes an interesting process from both the industrial and health points of view, because of the remarkable reduction in the processing time and the preservation of high concentrations of flavonoids, which have important claims to health benefits from biological activities.

Effects of temperature and pectin edible coatings with guava by-products on the drying kinetics and quality of dried red guava.

With the objective of utilizing agro-industrial by-products and enhancing the quality attributes of dehydrated fruits, this study evaluated the effects of edible pectin-based coatings containing disintegrated guava by-products (up to 50% concentration) and drying temperatures (46-74 °C) on the drying kinetics and nutritional properties of dried red guava. Coatings were applied to guava slices prior to hot-air drying. A central composite rotatable design was used to optimize carotenoid and phenolic compound retention. The effects of the edible coating compositions combined with the drying temperatures affected the effectiveness of the film as a barrier to carotenoid oxidation. Total phenolic compound retention, however, was affected only by temperature. Responses were simultaneously optimized, and high carotenoid and total phenolic retentions were obtained at approximately 60 °C with 25% by-product concentration. The effective water diffusivities were mainly affected by temperature. Consequently, the coatings improved nutritional quality without having a major impact on drying times.

A nonstaining and tasteless hydrophobic salt of chlorhexidine.

Chlorhexidine (CHX) remains one of the most effective and widely used antiplaque agents around the world, although its side effects still limit a long-term usage as the patient compliance for oral treatment with CHX. We hypothesize that a less water-soluble tetracation salt of CHX might be able to interact weakly with tooth enamel and oral taste cells, reducing those undesirable side effects of CHX. The chlorhexidine tetrapalmitate (CHXTP) was obtained and the antimicrobial activity was evaluated by hole-plate diffusion method and twofold tube dilution method; for measurement of its propensity to stain, we used the in vitro method of polymethylmethacrylate blocks in an infusion with black tea solution; the rate of its removal from oral cavity was studied by high-performance liquid chromatography measurement of CHX extracted from human saliva samples; and its effect on the human taste perception was evaluated by taste confusion matrix method. The results showed that CHXTP salt is very active against Streptococcus mutans, with no interference on taste perception and a low tendency to stain; however, chlorhexidine digluconate shows a better retention in saliva. The use of polyvinylpyrrolidone turned possible a nonstaining and tasteless CHXTP formulation to linger in mouth.

Aspectos sensoriais e fpisico-químicos de iogurtes de soja com espessantes/estabilizantes a base de fécula de inhame (Dioscorea alata), amido modificado e gelatina / Sensorial and physical-chemical aspects of soy yogusts with yam (Dioscorea Alata) starch, modified starch and gelatin as stabilizers /thickeners

Este estudo teve como objetivo avaliar o efeito da fécula de inhame, amido modificado da Cargill-Brasil (Amidomax 4800) e gelatina da Geklita-Brasil(GEL-LAC) como espessantes/estabilizantes em diferentes proporções e combinações em "iogurte" de soja fermentado com Enterococcus faecium e Lactobacillus helveticus ssp jugurti. Dez formulações de "iogurte" de soja contendo os diferentes espessantes?estabilizantes, sempre totalizando 0,5 por cento em relação à formulação final, foram analisadas em termos sensoriais e físico-químicaos. Com base nos resultados observados concluiu-se que sob o ponto de vista sensorial o produto mais adequado fopi processado apenas com gelatina na concentração de 0,5 por cento. Esse produto também apresentou os melhores resultados físico-químicos em relação à consistência, sinérese e capacidade de retenção de água. No entanto, a gelatina utilizada isoladamente provocou aumento no tempo de fermentação do iogurte de soja.

Desenvolvimento de terminologia descritiva e perfil sensorial de cremes de leite acondicionados em embalagens de folha de flandres e tetra brik / Development descriptive terminology and sensory profile of milk creams packed both in tin foil and tetra brik

Terminologia descritiva e perfil sensorial de cremes de leite nacionais, acondicionados em tetra brik e folha de flandres foram desenvolvidas através de análise sensorial descritiva. Análise descritiva quantitativa foi aplicada em conjunto com método de rede para o desenvolvimento da terminologia descritiva. Onze termos que melhor descreveram as similaridades e diferenças entre as amostras foram gerados. Em consenso os provadores definiram os descritores, materiais de referência e ficha de avaliaçäo das amostras. Após treinamento, nove provadores foram selecionados para compor a equipe de julgadores, com base em habilidade discriminatória, reprodutibilidade dos julgamentos e consenso do indivíduo com a equipe. A intensidade de cada descritor foi avaliada em cada amostra através de escala näo estruturada de 9 cm ancorada nos extremos nos termos "pouco" e "muito". Os dados foram analisados por ANOVA, Teste de Turkey (pó0.05) e Análise de Componente Principal (ACP). Os resultados indicaram que amostras de creme de leite acondicionadas em folha de flandres apresentaram maior intensidade de consistência, aroma de cozido e sabor residual, que as amostras embaladas em tetra brik. Por outro lado, as amostras acondicionadas em tetra brik foram caracterizadas por maior intensidade de cor, aroma, sabor de leite e sabor doce, em relaçäo às amostras enlatadas. Encontrou-se correlaçäo linear entre dados sensoriais e instrumentais para as medidas de cor. As técnicas sensoriais aplicadas revelaram-se apropriadas para caracterizar sensorialmente os produtos avaliados