Microbial biosurfactants with high ability to reduce surface and interfacial surface tension and conferring important properties such as emulsification, detergency, solubilization, lubrication and phase dispersion have a wide range of potential applications in many industries. Significant interest in these compounds has been demonstrated by environmental, bioremediation, oil, petroleum, food, beverage, cosmetic and pharmaceutical industries attracted by their low toxicity, biodegradability and sustainable production technologies. Despite having significant potentials associated with emulsion formation, stabilization, antiadhesive and antimicrobial activities, significantly less output and applications have been reported in food industry. This has been exacerbated by uneconomical or uncompetitive costing issues for their production when compared to plant or chemical counterparts. In this review, biosurfactants properties, present uses and potential future applications as food additives acting as thickening, emulsifying, dispersing or stabilising agents in addition to the use of sustainable economic processes utilising agro-industrial wastes as alternative substrates for their production are discussed.

This study assessed the occurrence of an enhancing inhibitory effect of the combined application of Origanum vulgare (OV) and Rosmarinus officinalis (RO) essential oils against bacteria associated to minimally processed vegetables using the determination of Fractional Inhibitory Concentration (FIC) index, kill-time assay in vegetal broth and application in vegetable matrices. Moreover, it was determined chemical composition of the essential oils and their effects alone and in mixture on sensory characteristics of minimally processed vegetables. Carvacrol (66.9 g/100 g) was the most prevalent compound in OV essential oil, while for RO was 1.8-cineole (32.2 g/100 g). OV and RO essential oil showed MIC in a range of 1.25-5 and 20-40 μL/mL, respectively. FIC indices of the combined application of the essential oils were 0.5 against Listeria monocytogenes, Yersinia enterocolitica and Aeromonas hydrophilla suggesting a synergic interaction. Only for Pseudomonas fluorescens FIC index was 0.75 purposing additive effect. Application of the essential oils alone (MIC) or in mixture (¼ MIC + ¼ MIC or ¼ MIC + ½ MIC) in vegetable broth caused significant decrease (p b 0.05) in bacterial count over 24 h. Mixture of essential oils reduced (p b 0.05) the inocula of all bacteria in vegetable broth and in experimentally inoculated fresh-cut vegetables. Similar efficacy was found to reduce the autochthonous microflora in vegetables. Sensory evaluation of vegetables sanitized with essential oils revealed that the scores of the most evaluated attributes fell between like slightly and neither like nor dislike. The combination of essential oils at sub-inhibitory concentrations could mean an interesting approach to sanitize minimally processed vegetables.

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Objetivou-se comparar os parâmetros físico-químicos e termo-oxidativos do óleo bruto de buriti com o refinado, como também determinar o teor de vitamina A, perfil lipídico e potencial antioxidante destes óleos. Amostras de óleo bruto e refinado foram avaliadas quanto à viscosidade, densidade relativa, índices de refração, acidez, ácidos graxos livres, peróxido e de iodo, grau de oxidação lipídica por UV-Vis, termogravimetria, calorimetria, capacidade antioxidante, teor de vitamina A e perfil de ácidos graxos. O refino do óleo diminuiu o percentual de ácidos graxos livres e os índices de acidez, de iodo e de peróxido, apresentando maior estabilidade termo-oxidativa que o óleo bruto. Porém sua capacidade antioxidante, o teor de vitamina A e o de ácidos graxos insaturados foram reduzidos em relação ao óleo bruto. Logo, sugere-se a otimização do processo de refino para minimizar perdas nutricionais no óleo de buriti, que por suas características pode ser considerado um alimento funcional.The objective of this study was to compare the physicochemical, thermo-oxidative and nutritional characteristics of crude and refined buriti oil. Crude and refined oil samples were evaluated for viscosity, relative density, refraction, acidity, free fatty acids, peroxide and iodine, lipid oxidation degree by UV-Vis, thermogravimetry, calorimetry, in vitro antioxidant capacity, vitamin A content and fatty acids profile. The refining process decreased the free fatty acids percentage and acidity, peroxide and iodine indexes, with greater thermal-oxidative stability, which is critical for its use in cooking food. However, its antioxidant capacity, vitamin A and unsaturated fatty acids contents were reduced compared to crude oil. Therefore, it is suggested to optimize the refining process to minimize nutritional losses in buriti oil, which due to its characteristics, can be considered a functional food.

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Origanum vulgare L. (oregano), Lamiaceae, has been known as plant specie with prominent biological properties for a long time. This study aimed to evaluate the antibacterial activity of Origanum vulgare essential oil on various Gram-positive and Gram-negative spoiling and/or pathogen food-related bacteria, as well as to observe its antimicrobial effectiveness in a food conservation micromodel. The results showed a strong antibacterial activity of the assayed essential oil noted by large growth inhibition zones (30-37 mm). MIC values were between 20-40 µL/mL for the most bacteria strains. Essential oil was able to cause significant (P<0.05) inhibitory effect on the bacteria viability providing a bacteriostatic effect after 24hours of exposure. In addition, the MIC provided a significant (P<0.05) decrease of the autochthonous bacterial flora in ground meat samples stored under refrigeration. These results support the possibility of using Origanum vulgare essential oil as alternative antimicrobial compound in food conservation systems.

O trigo como matéria-prima pode ser considerado como responsável pela qualidade da sua farinha, considerando-se a diversidade das variedades de grãos existentes, bem como as condições de clima e solo de cada região. O trigo possui importante papel no aspecto econômico e nutricional da alimentação humana, pois a sua farinha é largamente utilizada na indús-tria alimentícia (FERREIRA, 2003; GIEKO;DUBKOVSKY;.A qualidade do grão de trigo é o resultado da interação das condições de cultivo (interferência do solo, clima, pragas, manejo da cultura e da cultivar), em soma à interferência das operações de colheita, secagem e armazenamento, fatores estes AbstractWheat flour has a wide range of applications in the food industry, with an important economic and nutritional role in the human diet. It is known that the nutritional and technological aspects of wheat flour depend on the cultivation, harvesting, drying and storage conditions of the wheat grains used as raw material. This research aimed at analyzing the technological quality of samples of national and imported wheat grains, as well as of flour samples obtained from them. For this, physical-chemical (moisture, wet gluten, mineral content, falling number, hectoliter weight) and farinographic (water absorption, development time, stability) analyses were carried out. Physical-chemical analyses showed significant differences (p < 0.05) in the mineral content, wet gluten and falling number of the imported and national grain samples, and also among the flour samples obtained from them. Moisture was the only physical-chemical parameter that did not present a significant difference (p < 0.05) among the national and imported samples. Imported wheat grains and their flours presented higher values for wet gluten (28.0-33.4 %) and falling number (322.33-428.33 seconds), when compared to the national samples. Farinographic analyses showed a significant difference (p < 0.05) in water absorption, development time and stability among the national and imported wheat flour samples. Moreover, the farinographic analyses presented noteworthy values for water absorption (54.43-59.30 %) and stability (10.0-24.75 minutes) for the imported wheat flours. These results showed a lower technological quality of the national wheat grains and flours studied, when compared to the imported samples, with a negative interference in their industrial use and economic value. Keywords: wheat; wheat flour; technological quality. ResumoA farinha de trigo possui variadas aplicações na indústria de alimentos, apresentando um importante papel no aspecto econômico e nutricional da alimentação humana. Sabe-se, que as características nutricionais e tecnológicas da farinha de trigo sofrem interferência direta das condições de cultivo, colheita, secagem e armazenamento dos grãos de trigo utilizados como matéria-prima. Este estudo objetivou avaliar a qualidade tecnológica de amostras de grãos de trigo nacionais e importados, bem como de amostras de farinhas produzidas a partir destes grãos, através da análise de par...