Coffee adulteration

White (1995), not for a sensory analysis but mainly with a view to determining coffee adulterations, used the data of combined headspace GC and high-performance LC for multivariate analysis. Principal component analysis visualized the relationship between samples, and the outlying samples could be identified. The method could be an additional tool for classification and quality control of coffee products. 

White D.R. (1995) Coffee adulteration and a multivariate approach to quality control. 16th Int Colloq. Chem Coffee (Kyoto, 9-14.4.1995) (ASIC, 1995), 259-66. 

Caramel color interacts with other food components. As an example, a concentration higher than 700 ppm caramel in cola increased the rate of hydrolysis of the aspartame, forming alpha-L-aspartyl-L-phenylalanine. Caramelization products inhibited enzymic browning by 85.8 and 72.2% when heated at pH 4 and 6, respectively, for 90 min. The highest inhibitory activity was found for the fraction with molecular weight of 1000 to 3000. Caramel is often used for adulteration of juices and other foods like honey or coffee. It can be determined by quantification of marker molecules such as 5-HMF, 4-Mel, and DFAs. ... 

A Pittet, D Tornare, A Huggett, R Viani. Liquid chromatographic determination of ochratoxin A in pure and adulterated soluble coffee using an immunoaffinity column cleanup procedure. J Agric Food Chem 44 3564-3569,1996. 

Coffee/ Romance of Coffee/ All About Tea, and Romance of Tea. There is also the chapter on coffee and tea by Ukers and Prescott in the Jacobs treatise. Neumann, in 1735, wrote Vorn Tee, Caffee, Bier, und Wein. Wiley s Beverages and Their Adulteration was a well-known text. The topic Genussmittel looms large in German literature. 

Prodolliet J., Bruelhart M., Blanc M.B., Leloup V. et al. (1995b) Adulteration of soluble coffee with coffee husks and parchments. J. Ass. Off. Anal Chem. 78(3), 761-7. 

Or a spoonful of ground coffee may be placed in a small bottle of cold water, and shaken for a moment if the sample of coffee is pure, it will rise to the surface and hardlr tinge the water, whilst if the coffee is adulterated with chicory, the latter will fall to the bottom and color the water as before. A similar coloration of the water will bo produced, however, if the coffee be adulterated with burnt sugar, which is the basis of the so-called coffee essences or extracts. ... 

A radiometric method utilizing liquid scintillation counting has been developed which can assist in evaluation of the presence and degree of adulteration of plant extraction material with its synthetic counterpart. The basis of the method is the measurement of the decrease in the ambient radiocarbon level of the plant material caused by the addition of petroleum derived synthetic material. Cinnamic aldehyde used for evaluating the quality of cinnarmn, and caffeine extracted from tea and coffee are two products which lend themselves well to this method of analysis. The procedures for sample preparation, liquid scintillation counting and accuracy in evaluating product adulteration are discussed. 

Light microscopy (LM) is regularly used to obtain rapid, inexpensive qualitative and quantitative information in food analysis. The first routine use of LM in food analysis was for the identification of adulteration (e.g., the presence of chicory root in coffee) or contamination (insect, rodent, microbial, and foreign bodies). Bright-field, polarizing, and fluorescent microscopy are the three traditional LM techniques used most frequently in food analysis. The basic instrument is a conventional compound (bright-field) microscope, to which polarizing and fluorescence accessories are easily attached. 

GC-MS coupled with chemometric techniques has been used to characterize roasted coffees [54], to detect adulterants in olive oils [55], and to determine fatty acids in fish oils [56], GC-MS data have also been used in toxicology assessments to reveal patterns in complex chemical mixtures with the help of multivariate analyses [57,58],... 

Bemal et al. (1996) also determined seven monosaccharides present in instant coffee. A C-18 SPE step was again used before analysis to protect the chromatography system. Two of the coffees used in this study were adulterated. This was easily detectable because the levels of glucose and fructose were elevated compared to the... 

Accum F (1820) A treatise on adulterations of food, and culinary poisons exhibiting the fraudulent sophistications of bread, beer, wine, spiritous liquors, tea, coffee, cream, confectionery, vinegar, mustard, pepper, cheese, olive oil, pickles, and other articles employed in domestic economy. Abraham Small, Philadelphia... 

Food law was largely concerned with protection of the revenues from tea, coffee, hops and sugar, but in view of the widespread adulteration of bread with alum, rice flour, potatoes, beans and peas, an anti-adulteration law was passed in the early nineteenth century. Medical practitioners were the first to register their scientific concern to the State the findings of the Committee of Inquiry into the cholera epidemic of 1854 helped the profession to gain a hold on the sanitary laws of the UK. 

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