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Coffee Powder (coffee + powder)

Distribution by Scientific Domains

Chemistry	75%

Selected Abstracts

QUANTIFYING ADULTERATION IN ROAST COFFEE POWDERS BY DIGITAL IMAGE PROCESSING

JOURNAL OF FOOD QUALITY, Issue 2 2003
EDSON E. SANO
Pure arabica coffee and mixtures of coffee husks and straw, maize, brown sugar and soybean were produced in our laboratory as investigation materials. Red/Green/Blue (RGB) color composites, magnified twelve times, were generated using a Charge Coupled Device (CCD) camera connected to a stereo microscope and a personal computer with an image processing software package. The percent areas of the contaminants in each image were calculated by the Maximum Likelihood supervised classification technique. Best-fit equations relating weight percentage (g.kg -1) and the percent areas were obtained for each coffee contaminant. To test the method, 247 coffee samples of different amounts and types of adulterants were analyzed in the laboratory. The results showed that the new method developed can analyze precisely and quickly a large number of ground coffee powders. [source]

Solid-phase aroma concentrate extraction (SPACEÔ ): a new headspace technique for more sensitive analysis of volatiles

FLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2004
Masashi Ishikawa
Abstract The SPACEÔ (solid-phase aroma concentrate extraction) method is a modi,ed version of the SPME (solid-phase micro extraction) technique for headspace analysis, with increased area of the adsorbent to enable more sensitive analysis of volatiles. The SPACEÔ rod used in the technique is fabricated from stainless steel coated with an adsorbent mixture, consisting mainly of a graphite carbon. Initially, the SPACEÔ rod is ,xed in the head of a closed ,ask, where it adsorbs the aroma. Next, the rod is thermally desorbed on-line with a high-resolution gas chromatography,mass spectrometer (HRGC,MS). In the present experiments, SPACEÔ sampling reproducibility was determined by analysing a standard mixture and roasted coffee beans. The SPACEÔ rod collected the analytes with good reproducibility, with the exception of high polar compounds. Similar analyses of coffee powder were performed by SPME and other methods for comparison with the SPACEÔ method. The SPACEÔ method proved to have superior capabilities with high concentrations, and it produced a well-balanced chromatogram. Copyright © 2004 John Wiley & Sons, Ltd. [source]

An enzyme-linked immunosorbent assay for monitoring of Aspergillus ochraceus growth in coffee powder, chilli powder and poultry feed

LETTERS IN APPLIED MICROBIOLOGY, Issue 1 2006
S. Anand
Abstract Aims:, The work was carried out to develop an immunoassay for estimation of Aspergillus ochraceus biomass on solid substrate. Methods and Results:, An indirect noncompetitive enzyme-linked immunosorbent assay (ELISA) was developed for determination of fungal biomass in food commodities using antibody raised against A. ochraceus mycelial antigen. The sensitivity of the assay was linear in the range of 10,160 ,g fungal biomass per millilitre extract of coffee (R2 = 0·989), poultry feed (R2 = 0·987) and chilli (R2 = 0·989). The growth of A. ochraceus in the food commodities like chilli, coffee beans and poultry feed, under the influence of two levels of moisture (20% and 30%) were monitored by the ELISA. The maximum fungal colonization was observed in poultry feed (9·8 and 11·8 mg g,1) followed by coffee beans (6·8 and 11·3 mg g,1) and chilli (5·1 and 6·3 mg g,1) at 20% and 30% moisture after 20 days of incubation. Similarly the fungus produced maximum ochratoxin A in poultry feed (25 and 120 ,g g,1) followed by coffee beans (8 and 24 ,g g,1) and chilli (0·2 and 0·45 ,g g,1) at 20% and 30% moisture after 20 days of incubation. Conclusions:, The method can be used for quantitative estimation of fungal biomass and comparison of fungal colonization in food substrates varying in composition. Significance and Impact of the Study:, The method can be adapted for studying the fungal colonization in different solid substrates under different culture condition. The method is sensitive to mould colonization of ,0·02% (w/w) and can be used for early detection of specific fungal infestation in food commodities. [source]