ANALYSIS OF BLENDS OF RAW COFFEES OF ARABICA AND ROBUSTA VARIETIES BY ~1H NMR AND CHEMOMETRIC METHODS

摘要

The coffee drink is prepared from arabica or robusta specie grain, or even from blends of them. Arabica coffee presents more pronounced and refined flavor and its price is higher than robusta. Although the best coffee drink is obtained from arabica specie grain, blends of both are necessary in several proportions depending on consumers taste, the price rate or if it will be used to produce instant coffee or not, because robusta specie yields more soluble solids than arabica. Although arabica and robusta can been distinguished by their grain size, this visual criterion is not practical for blends with inhomogeneous grain size and it is useless after roasting and grinding. Due to this and many other reasons there is a great need for techniques that can discriminate both species and help the taster in the coffee classification to maintain the blends quality.