CHANGES IN TEXTURAL PROPERTIES AND COLOR DUE TO THE PROCESSING METHOD OF GREEN COFFEA ARABICA

Abstract

Choosing a suitable method of green coffee beans processing is one of the first steps that can significantly affect the final product. Thus, the objective of this study was to evaluate how the processing method affects the selected observed parameters (dry matter, water activity, pH, hardness, color). The postharvest processing of coffee cherries involves natural dry, semi-washed, or wet processing. On-farm postharvest coffee processing is essential for ensuring high quality of coffee cup and constitutes a chain of interlinked phases mainly aimed at removing the cherries' mucilage and drying the beans to a low moisture content of 10 to 12% (mass/mass). The coffee samples were of American origin Coffea arabica. A total of 12 samples from multiple regions were used. Samples of Coffea arabica were collected into three groups natural (dry), pulped natural (semi-washed), and wet processing (fully washed). The processing results, to some extent, influence the values ​​​​of the monitored parameters. The highest dry matter value was indicated in dry processing, and the highest value of water activity was in wet processing. The average value of pH was 5.74. Natural processing showed the most significant differences between individual groups concerning color processing. On the other hand, wet and dry processing showed very similar colors. Values of hardness were in range     86549.05 - 100674.90 g. The final quality of the green coffee beans is thus dependent on the different agricultural, and farm practices applied, which depend on the coffee plant cultivar, geography, weather conditions, and available infrastructure.