New method discovered to test for antioxidants in chocolate
UBC food scientists have come up with a cheaper and faster way to measure the levels of antioxidants in chocolate. They are planning on using this method to recognize when antioxidant levels rise and fall during the manufacturing process, from raw cocoa beans to chocolate bars. “Our method predicts the antioxidant levels in chocolate in under a minute, compared to the industry standard that can take several hours or even days,” said Xiaonan Lu, an assistant professor in food, nutrition and health in the faculty of land and food systems, who developed the method alongside PhD student Yaxi Hu. “It’s not a substitute for the traditional method used at the moment, but it does show a strong correlation for being just as reliable.”The UBC procedure uses infrared spectroscopy, a technology which illuminates infrared light onto chocolate samples. The infrared spectra record the chemical composition of each sample, including the levels of polyphenols, micronutrients with high antioxidant properties. The conventional method depends on biochemical tests to read absorbance values which are expensive and time consuming. Hu said testing antioxidant levels will help chocolatiers select better beans, and also to improve their processing parameters. Chocolate is manufactured through various processing stages from drying, to roasting and to fermentation, from chocolate beans. UBC food scientists are starting to use their method to measure cocoa beans from different countries in each stage to pin point when antioxidants are at their highest and lowest levels. “If we identify drying as the step that significantly lowers the bean’s antioxidant properties, for example, we will want to develop a strategy to reduce the drying time, or drying temperature,” said Lu. Finding the antioxidant level could be valuable information for chocolate companies wanting to make products high in antioxidants, appealing more to health conscious consumers. Antioxidants are beneficial to human health and help contribute to the prevention of cancers, vision loss and heart diseases. They are usually found in foods like pecans, blueberries and chocolate. The research is in its early stages as the scientists test hundreds of samples. This new method used to quantify antioxidant levels was funded by a local chocolatier in Metro Vancouver, the Natural Sciences and Engineering Research Council (NSERC) and by the non-profit MITACS. The UBC food scientists are hoping to receive more funding, specially from a major chocolate company, to advance their studies.