Effect of grinding, extraction time and type of coffee on the physicochemical and flavour characteristics of cold brew coffee

Abstract

The efects of grinding (medium-coarse) and extraction time (14–22h) on the physicochemical and sensorial properties of cold brew cofee produced using two types of Colombian specialty cofees (Huila and Nariño) were evaluated. Cold cofee brewed under coarse grinding and 22h of extraction exhibited the highest values of total dissolved solids, extraction yield, pH, titratable acidity (TA), and total phenolic content. The type of cofee used mainly afected the TA and pH. All cold brew cofee samples had lower TA values than their hot counterparts. Nariño cold brew samples had higher TA values than those of Huila in all treatments evaluated. Higher scores were reported in the sensorial evaluation of cold brew cofee when prepared using the shortest time (14h) and coarse grinding for both cofee types. These cofees were characterized by strong sweetness, fruity and foral favours, medium bitterness and acidity, and a creamy body. Furans, pyrazines, ketones, aldehydes, pyrroles, esters, lactones, furanones, and phenols were detected as odour-active compounds. The fndings of this study demonstrate that the particle size, contact time, and cofee type afect the physicochemical and sensorial characteristics of cold brew cofee, leading to cold brew cofees with diferent favour profles