Analytical method to detect adulteration of ground roasted coffee

Abstract

In this work, an HPLC-based detection method for identification of coffee powder adulterated with roasted barley, wheat and rice powders was developed by using various chemical indices such as monosaccharides (mannose, rhamnose, glucose, galactose, xylose and arabinose), trigonelline and nicotinic acid. As a quality assurance, the recovery efficiencies were 84.1%-90.2% for the monosaccharides, 113.6% for trigonelline and 114.9% for nicotinic acid. The limits of detection were 0.047-0.070 mmol kg À1 for the monosaccharides, 0.209 mg kg À1 for trigonelline and 0.117 mg kg À1 for nicotinic acid. The glucose concentration in coffee samples adulterated with roasted barley, wheat and rice at 99:1 (w/w) mixing ratio was significantly different from the control coffee sample. The limit of discrimination from adulterated coffee samples was 1% (w/w) when glucose was used as a chemical index (P < 0.05).a Linear ranges were measured for six concentrations (0.5, 1, 2, 5, 10 and 20 mmol L Àl ). b LOD = 3.14 9 SD/slope (mmol kg À1 ). c LOQ = 10 9 SD/slope (mmol kg À1 ). d Linear ranges were measured for six concentrations (1, 5, 10, 50, 100 and 500 mg kg À1 ).Analysis of coffee adulteration H. Y. Song et al.

Effect of microwave and oven roasting methods on total phenol, antioxidant activity, phenolic compounds, and fatty acid compositions of coffee beans

“…Coffee beans are used in food industry to produce the most consumed beverage in the world (Song, Jang, Debnath, & Lee, 2019). Among all commodities worldwide, coffee ranked the second following crude oil as most traded food commodity (International Coffee Organization, 2016).…”

HPLC-Based Chemometric Analysis for Coffee Adulteration

“…Applications of HPLC for the detection of adulterated coffee were mainly based on targeted methods. Analytes such as oligosaccharides, monosaccharides, trigonelline, and/or nicotinic acid were applied as markers to identify adulterants in coffee [ 7 , 8 , 9 , 11 ]. In this study, HPLC with non-targeted analysis was developed to differentiate coffee adulteration.…”

“…Several analytical methods have been proposed to identify the adulteration of ground roasted coffee, including gas chromatography-mass spectrometry (GC-MS) [ 3 ], high-performance liquid chromatography (HPLC) [ 7 , 8 , 9 ], ultraviolet-visible spectrophotometry (UV-Vis) [ 10 ], ultra-performance liquid chromatography (UPLC) [ 11 ], Fourier-transform infrared spectroscopy (FTIR) [ 12 ] and voltammetric electronic tongue [ 13 ]. The above methods apply either targeted- or non-targeted analysis methods.…”

“…In a review of the literature, detecting coffee adulteration by using liquid chromatography belongs to a target analysis method that analyzes compounds (carbohydrates) in coffee and adulterated coffee to accomplish the distinction [ 7 , 8 , 9 , 11 ]. In contrast, spectroscopy methods have evolved as non-target analytical methods to detect coffee adulteration.…”

Application of genetic algorithm and multivariate methods for the detection and measurement of milk‐surfactant adulteration by attenuated total reflection and near‐infrared spectroscopy

“…This is a threat to public health. This adulteration is not only limited to milk but can also be observed in other foods like olive oil, honey, saffron, orange juice, coffee, apple juice, and nuts 2–11 . Milk has been reported to be adulterated by inexpensive, inferior quality, and harmful chemical substances to increase the volume, mask the quality parameters (e.g., protein and fat content), and prolong the product's shelf life 11–13 …”