FTIR and PLS-regression in the evaluation of bioactive amines, total phenolic compounds and antioxidant potential of dark chocolates.

Cloning techniques are used to improve agronomical traits and answer to the demand for fine chocolate. The objective of this study was to predict the concentrations of bioactive amines, phenolic compounds, and the antioxidant potential of dark monoclonal chocolate from nine fine cocoa varieties by FTIR analysis and conventional techniques. Total phenolic compounds, bioactive amines and antioxidant activity varied significantly among chocolates. The antioxidant activity was also affected by the analytical method (DPPH vs. Rancimat). Chemometric models based on FTIR data provided satisfactory predictions of the concentrations of the amines: spermidine (R2 = 0.92; RMSEP = 0.39; RMSEC = 0.21), tryptamine (R2 = 0.92; RMSEP = 0.41; RMSEC = 0.20), cadaverine (R2 = 0.82; RMSEP = 1.58; RMSEC = 0.75) and tyramine (R2 = 0.87; RMSEP = 1.87; RMSEC = 0.68); as well as phenolic compounds and antioxidant activity by Rancimat® (R2 = 0.98; RMSEP = 0.32; RMSEC = 0.21) and DPPH (R2 = 0.97; RMSEP = 4.05; RMSEC = 1.66). The wavenumbers of amines vibrations are among those that most affected antioxidant prediction models, confirming the contribution of amines to the antioxidant activity of chocolates.

In vitro bioaccessibility of amino acids and bioactive amines in 70% cocoa dark chocolate: What you eat and what you get.

Chocolate is an important source of free bioactive amines and amino acids which play important roles in human health. Considering the limited information on the bioaccessibility of these compounds from chocolate, the objective of this study was to characterize their profiles and bioaccessibility in 70% cocoa dark chocolate through in vitro simulation of oral, gastric and intestinal digestions. Seven amines were detected; polyamines were predominant before in vitro digestion, whereas tyramine, cadaverine and spermidine after digestion. All amines showed high bioaccessibility with slight influence of digestive enzymes. Amines increased after gastrointestinal digestion: tyramine (13-fold), tryptamine (9-fold), others (2.4-4.2-fold) and histamine appeared. All amino acids, GABA and ammonia were detected in chocolate, and their contents increased after in vitro digestion due to digestive enzymes (4.6, 2.8 and 2.1, respectively). Dark chocolate protein is a good source of tryptophan, phenylalanine + tyrosine, isoleucine, histidine, but limiting for lysine, leucine, and threonine.

Teores de mercúrio em mexilhões do mercado consumidor e influência do tratamento térmico / Mercury contents in mussels from the retail market and influence of thermal processing

A contaminação por mercúrio é um desafio para a saúde humana e animal. Os moluscos bivalves, especialmente os mexilhões, absorvem, retém e concentram o mercúrio. Este trabalho teve como objetivo determinar os teores de mercúrio em mexilhões do mercado varejista de Belo Horizonte, MG e investigar a influência do tratamento térmico. Foram analisadas 42 amostras de mexilhão marrom procedentes de cultivo marinho. Os teores de mercúrio foram determinados por espectrometria de absorção atômica de combustão após amalgamação em ouro. Todas amostras tinham mercúrio em teores que variaram de 0,020 a 0,076 mg/kg. Nenhuma amostra apresentou teor de mercúrio superior ao limite estabelecido pela legislação brasileira (0,05 mg/kg para crustáceos, moluscos e cefalópodes). O cozimento do mexilhão por 3 e 6 min não foi eficaz na eliminação do Hg.