| dc.description.abstract | Coffee is one of the most consumed beverages in the world. Due to its commercial importance, detection of adulterated matters has been a constant concern in fraud verification, especially when it is difficult to percept adulterations with the naked eye in samples of roasted coffee ground. In Vietnam, the most common adulterated materials are corn and soybean. This study was performed in order to detect and quantify adulteration in commercial roasted ground coffee products. The floatation, spot check and microscopic methods were applied to detect adulterants in ground coffee samples, while caffeine was used as a chemical maker to quantify the level of adulteration. Ground coffee samples were taken from national brands, local brands and street vendors. The flotation test using cold water in combination with spot check and microscopic examination appeared to be effective tools for detection of corn and soybean. Using corn as a model of the adulterant, then the caffeine content in ground coffee was well correlated with the amount of corn added, which allowed estimation of the adulteration quantity possible. The results from qualitative tests revealed that 90% of the commercial ground coffee samples were adulterated, either with corn and/or soybean. Projection from the caffeine content regression showed that level of adulteration in the studied samples was in a range from 10.0 up to 47.0%.
Key words: adulteration, caffeine, coffee, spot check, flotation test, microscopic test. | en_US |
