Oxidative stability and physicochemical changes of dark chocolates with essential oils addition.

This research aimed to evaluate the oxidative stability and rheological properties of dark chocolates with the addition of essential oils (EO) of Cymbopogon citratus, Pimpinella anisum, and Mintostachys mollis. For this purpose, before the inclusion in chocolates, the EO were chemically characterized to identify the most important volatile compounds. We added essential oils of P. anisum, C. citratus and M. mollis to dark chocolates (cocoa 70%) at doses of 10, 12 and 14 µL per 500 g, separately. These chocolates were evaluated for oxidative activity, hardness, microstructure, rheological and melting properties and antioxidant capacity. It was found that C. citratus EO (10 µL/500 g of chocolate) improve the oxidative stability of the chocolates at 90 days of storage at 25 °C (230 meq O2/kg), while higher concentrations promote lipid oxidation. The incorporation of essential oils improves the antioxidant capacity, likewise, it changes the rheological, thermal, and microstructural properties. Therefore, essential oils can improve the physicochemical characteristics of dark chocolates allowing greater stability in oxidative fat and thus increase the shelf life.

Changes in bioactive compounds during fermentation of cocoa (Theobroma cacao) harvested in Amazonas-Peru.

Cocoa (Theobroma cacao) is the main raw material for the production of chocolate; it is considered the food of the gods, as it possesses a diversity of bioactive compounds beneficial to human health. The abundance of bioactive compounds, among others, is conditioned by the post-harvest processing of cocoa beans, and fermentation is a major step in this regard. Consequently, this research evaluated the changes in phenolic compounds and methylxanthines occurred in the fermentation of Criollo and CCN-51 cocoa beans, varieties of great commercial interest for the cocoa-growing areas of Peru. For this purpose, samples were taken every 12 h of cocoa beans under fermentation for 204 h in which phenols (gallic acid, caffeic acid, catechin, and epicatechin) and methylxanthines (theobromine, caffeine and theophylline) were quantified by ultra-high performance liquid chromatography (UHPLC); total polyphenols by Folin Ciocalteu; antioxidant capacity by DPPH free radical capture method; total anthocyanins; pH; titratable acidity; and fermentation rate of beans. We found that during fermentation, phenolic content, antioxidant activity, and methylxanthines of cocoa beans decreased; on the other hand, the anthocyanin content increased slightly. Indeed, at distinctly degree, fermentation influences bioactive compounds in cocoa beans, depending on the variety cultivated.

Physical, functional and sensory properties of bitter chocolates with incorporation of high nutritional value flours.

Due to the growing demand for healthy food products, the industry is seeking to incorporate inputs with high nutritional potential to traditional products. The objective of this research was to evaluate the effect of incorporating Lepidium meyenii, Chenopodium pallidicaule, Amaranthus caudatus, Sesamum indicum and Salvia hispanica flours on the physical, chemical, rheological, textural and thermal characteristics, and the degree of sensory acceptance of dark chocolate bars (65% cocoa). To this end, chocolate bars were made with the incorporation of five flours in four doses (1, 2, 3 and 4%), obtaining 20 different formulations compared with a control treatment (without flour addition). It was found that as flour incorporation levels increased, viscosity, antioxidants and particle size of the chocolates increased, but hardness and pH decreased. The addition of the flours also affected the acceptability and microstructure of the chocolate bars. The incorporation of up to 4% of the flours studied improved the degree of acceptance of the chocolates. Consequently, the incorporation of grain flours with high nutritional value can enhance the characteristics of dark chocolates, becoming a technological alternative for the chocolate industry.