Controlling the quality of grape juice adulterated by apple juice using ESI(-) FT-ICR mass spectrometry

Food quality control is undoubtedly a process of great importance. The technological development of the last years has increased the food production and consumption, thus generating, an enormous demand for the food quality control. Grape juice is a very tasty and high quality nutraceutical drink, being widely consumed worldwide. This product has a high commercial value, making it source of several types of fraud, such as other juices' addition, like apple juice. Through negative-ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry, it was possible to detect and quantify apple juice in integral grape juice. In this study, we used the univariate linear regression model using mixtures of integral grape juice with various concentrations of integral apple juice (0, 1, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75 and 100 wt %). The model showed good accuracy. In addition, eleven commercial samples of grape juice were tested, and in two of them, apple juice was detected at approximate to 25 wt%.