The first stage of chocolate production consists of a natural, seven-day microbial fermentation of the pectinaceous pulp surrounding beans of the tree Theobroma cacao. There is a microbial succession of a wide range of yeasts, lactic-acid, and acetic-acid bacteria during which high temperatures of up to 50 degrees C and microbial products, such as ethanol, lactic acid, and acetic acid, kill the beans and cause production of flavor precursors. Over-fermentation leads to a rise in bacilli and filamentous fungi that can cause off-flavors. The physiological roles of the predominant micro-organisms are now reasonably well understood and the crucial importance of a well-ordered microbial succession in cocoa aroma has been established. It has been possible to use a synthetic microbial cocktail inoculum of just 5 species, including members of the 3 principal groups, to mimic the natural fermentation process and yield good quality chocolate. Reduction of the amount of pectin by physical or mechanical means can also lead to an improved fermentation in reduced time and the juice can be used as a high-value byproduct. To improve the quality of the processed beans, more research is needed on pectinase production by yeasts, better depulping, fermenter design, and the use of starter cultures.

A total of 234 LAB isolates from Brazilian food products were initially screened for their ability to survive at pH 2.0. Fifty one of the isolates survived and were selected. They were characterized by phenotypic methods, rep-PCR and identified using 16S rRNA gene sequencing as Lactobacillus fermentum (34 isolates), Lactobacillus plantarum (10) and Lactobacillus brevis (7). Based on being either highly tolerant to bile, showing an ability for auto-aggregation and/or hydrophobic properties, one L. fermentum (CH58), three L. plantarum (CH3, CH41 and SAU96) and two L. brevis (SAU105 and FFC199) were selected. The highest co-aggregation ability with Escherichia coli was observed to L. plantarum CH41. L. brevis SAU105 and FFC199 and L. fermentum CH58 exhibited antagonistic activity towards the pathogens Listeria monocytogenes and Staphylococcus aureus. L. plantarum CH3 and CH41 and L. brevis FFC199 showed adhesion ability to Caco-2 cells (1.6, 1.1 and 0.9%, respectively) similar to the commercial probiotic, Lactobacillus rhamnosus GG (1.5%). They were able to increase the transepithelial electrical resistance (TEER) of Caco-2 cells over 24 h (p< 0.05). The present work showed that the probiotic characteristics were strain-specific and that the isolates L. plantarum CH3 and CH41 (cocoa) and L. brevis FFC199 (cauim) exhibited potential probiotics properties.

a b s t r a c tThe main aim of this work was to produce fruit wines from pulp of gabiroba, cacao, umbu, cupuassu and jaboticaba and characterize them using gas chromatographyemass spectrometry for determination of minor compounds and gas chromatography-flame ionization detection for major compounds. Ninetynine compounds (C 6 compounds, alcohols, monoterpenic alcohols, monoterpenic oxides, ethyl esters, acetates, volatile phenols, acids, carbonyl compounds, sulfur compounds and sugars) were identified in fruit wines. The typical composition for each fruit wine was evidenced by principal component analysis and Tukey test. The yeast UFLA CA 1162 was efficient in the fermentation of the fruit pulp used in this work. The identification and quantification of the compounds allowed a good characterization of the fruit wines. With our results, we conclude that the use of tropical fruits in the production of fruit wines is a viable alternative that allows the use of harvest surpluses and other underused fruits, resulting in the introduction of new products into the market.

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Microbial ecology and chemical composition of Brazilian kefir beverage was performed. The microorganisms associated with Brazilian kefir were investigated using a combination of phenotypic and genotypic methods. A total of 359 microbial isolates were identified. Lactic acid bacteria (60.5%) were the major isolated group identified, followed by yeasts (30.6%) and acetic acid bacteria (8.9%). Lactobacillus paracasei (89 isolates), Lactobacillus parabuchneri (41 isolates), Lactobacillus casei (32 isolates), Lactobacillus kefiri (31 isolates), Lactococcus lactis (24 isolates), Acetobacter lovaniensis (32 isolates),Kluyveromyces lactis (31 isolates), Kazachstania aerobia (23 isolates), Saccharomyces cerevisiae (41 isolates) and Lachancea meyersii (15 isolates) were the microbial species isolated. Scanning electron microscopy showed that the microbiota was dominated by bacilli (short and curved long) cells growing in close association with lemon-shaped yeasts cells. During the 24 h of fermentation, the protein content increased, while lactose and fat content decreased. The concentration of lactic acid ranged from 1.4 to 17.4 mg/ml, and that of acetic acid increased from 2.1 to 2.73 mg/ml. The production of ethanol was limited, reaching a final mean value of 0.5 mg/ml.