Impact of a Microbial Cocktail Used as a Starter Culture on Cocoa Fermentation and Chocolate Flavor.

Chocolate production suffered a vast impact with the emergence of the "witches' broom" disease in cocoa plants. To recover cocoa production, many disease-resistant hybrid plants have been developed. However, some different cocoa hybrids produce cocoa beans that generate chocolate with variable quality. Fermentation of cocoa beans is a microbiological process that can be applied for the production of chocolate flavor precursors, leading to overcoming the problem of variable chocolate quality. The aim of this work was to use a cocktail of microorganisms as a starter culture on the fermentation of the ripe cocoa pods from PH15 cocoa hybrid, and evaluate its influence on the microbial communities present on the fermentative process on the compounds involved during the fermentation, and to perform the chocolate sensorial characterization. According to the results obtained, different volatile compounds were identified in fermented beans and in the chocolate produced. Bitterness was the dominant taste found in non-inoculated chocolate, while chocolate made with inoculated beans showed bitter, sweet, and cocoa tastes. 2,3-Butanediol and 2,3-dimethylpyrazine were considered as volatile compounds making the difference on the flavor of both chocolates. Saccharomyces cerevisiae UFLA CCMA 0200, Lactobacillus plantarum CCMA 0238, and Acetobacter pasteurianus CCMA 0241 are proposed as starter cultures for cocoa fermentation.

Evaluation of the efficacy of flaxseed meal and flaxseed extract in reducing menopausal symptoms.

The objective of this study was to evaluate the efficacy of flaxseed meal and flaxseed extract in reducing climacteric symptoms of menopausal women. Ninety menopausal women were randomly distributed into three study groups: group I received 1 g per day of flaxseed extract containing at least 100 mg of secoisolariciresinol diglucoside (SDG), group II received 90 g per day of flaxseed meal containing at least 270 mg of SDG, and group III received 1 g per day of collagen (placebo group). Subjects were assessed for menopausal symptoms by the Kupperman index at the beginning and at the end of the 6 months of treatment. Subjects were also assessed for endometrial thickness and vaginal cytology. The Kupperman index values at the beginning and end of the treatments were analyzed using the paired t-test. Both the flaxseed extract (P=.007) and the flaxseed meal (P=.005) were effective in reducing the menopausal symptoms when compared with the placebo control (P=.082). Alternatively, the changes in Kupperman index were also computed and submitted to analysis of variance. In this case, no significant differences were found (P=.084) although the data indicate a decreasing tendency for the Kupperman index by both the flaxseed extract and the flaxseed meal groups. Neither the flaxseed extract nor the flaxseed meal exerted clinically important estrogenic effects on the vaginal epithelium or endometrium as revealed by the absence of changes in the blood levels of follicle stimulating hormone and estradiol, as well as in the endometrial thickness, and vaginal epithelial maturation value. No serious adverse events related to the treatments were reported. Although the results of the present study do not allow an unequivocal conclusion about the action of flaxseed on the menopausal symptoms, they suggest that it could be premature to conclude that no such action exists. Clearly the matter still deserves further experimental attention.

1H NMR, a rapid method to monitor organic acids during cupuassu (Theobroma grandiflorum Spreng) processing.

The development of an analytical method using 1H nuclear magnetic resonance (1H NMR) spectrometry to monitor cupuassu (Theobroma grandiflorum Spreng) bean fermentation, drying, and roasting processes is reported. The analysis of organic acids and alcohols of crude water extracts of cupuassu ground kernels were monitored by HPLC and 1H NMR spectroscopy. The residual protein signals caused deleterious effects on acid and alcohol quantifications. Therefore, the analytical procedures were optimized by sample cleanup and water suppression pulse sequences in order to obtain compatible data using HPLC and 1H NMR. The quantification of lactic acid, acetic acid, and 2,3-butanediol by NMR is 5- to 10-fold faster than by HPLC, with the advantage of providing the identification of several chemical species in a single experiment. Application of these analytical conditions to some cupuassu samples revealed that this methodology can be applied to the quality profiles of fermentation and roasting processes.

Citrate catabolism and production of acetate and succinate by Lactobacillus helveticus ATCC 15807.

The citrate metabolism of Lactobacillus helveticus ATCC 15807 was studied under controlled-pH fermentations at pH 4.5 and pH 6.2. The micro-organism was able to co-metabolize citrate and lactose at both pH from the beginning of growth, which enhanced the rate of lactose consumption and lactic acid production, compared with cultures without citrate. The effect of citrate on cell growth was dependent on the balance between the ratio of dissociated to non-dissociated forms of the acetic acid produced and the extra ATP gained by the cells, both facts related to the citrate metabolism. The citrate catabolism determined a change in the fermentation pattern of L. helveticus ATCC 15807 from homolactic to a mixed-acid profile, regardless of the external pH. Within this new fermentation pattern, acetate was the major product formed (13-20 mM), followed by succinate (2.4-3.7 mM), while acetoine, dyacetile or butanediol were not detected. The mixed-acid profile displayed by L. helveticus ATCC 15807 was linked to NADH(2) oxidase activity rather than the acetate kinase enzyme.

A simple GC method for determination of cryoprotector diols 1,4-butanediol or 2,3-butanediol in isolated rat hepatocytes.

We devised a simple method for determining the cryoprotectant agents 1,4-butanediol or 2,3-butanediol in isolated rat hepatocytes. After extraction of of hepatocytes with water (containing internal standard - ethylene glycol 1.25 mg/mL) the diol content was analyzed by gas chromatography. The method shows a linear response in the range 0.125 to 2.50 mg/mL for 1,4-butanediol and 0.25 to 3.75 mg/mL for 2,3-butanediol. The accuracy and precision of the method were evaluated and the coefficients of variation were found to be within = 6.0 %. The recoveries from hepatocyte samples containing 0.50, 1.00 and 2.00 mg/mL were 91.0 to 108 % for 1,4-butanediol and 80.6 to 100.3 % for 2,3-butanediol, respectively. This method allowed the determination of the intracellular concentration of diols in hepatocytes preserved for up to 120 hours at - 4 (C in UW solution + 8 % w/v 1,4-butanediol (or 2,3-butanediol).