Acids in coffee: A review of sensory measurements and meta-analysis of chemical composition

Abstract

Coffee contains a variety of organic acids (OAs) and chlorogenic acids (CGAs) that contribute to overall sensory properties. Large variations in preparation and measurement methodology across the literature complicate interpretation of general trends. Here, we perform a systematic review and meta-analysis of the published literature to elucidate the concentrations of OAs and CGAs in both Coffea arabica (arabica) and Coffea canephora (robusta), for both green coffee and roasted coffee at multiple roast levels. A total of 129 publications were found to report acid concentration measurements, yielding 8,634 distinct data points. Analysis of the full data set reveals several trends. First, roasted robusta has considerably more acidic compounds than arabica with 2 to 5 times as much total OAs, and much larger amounts of formic and acetic acid. As for CGAs, in both arabica and robusta 5-CQA is the major component, and progressive roasting decreases the concentration of all CGAs. The total amount of CGA present was more dependent on roast level than the type of coffee (arabica vs. robusta). Overall, this meta-analysis suggests that the increases in certain OAs with roast level might play more of a role in the sensory profile of dark roast coffees than previously suspected.

Whole‐wheat bread enzymatically bioprocessed and added with green coffee infusion had improved volume and were sensory accepted when consumers were informed of the presence of healthy substances

“…Nonetheless, these strategies increased the contents of ash, soluble fibres, phenolics, and methylxanthines (Table 1). The ash content was slightly higher in bread added with green coffee infusion and/or bioprocessed, due to the addition of minerals from green coffee and cocoa bran, materials that present ash contents of approximately 5% (Yeager et al ., 2021) and 7% (Amorim et al ., 2017), respectively.…”

“…The addition of green coffee infusion increased the content of phenolics for both GCB (43%) and BGCB (58%) (Table 1), which was expected since green coffee is known to be rich in chlorogenic acids (Yeager et al ., 2021). The increase in phenolics content due to green coffee addition, mainly in the form of chlorogenic acids, has already been reported for bread (Świeca, et al ., 2017; Świeca et al ., 2018; de Almeida et al ., 2020) and donuts (Budryn et al ., 2013).…”

Sensory Analysis of Full Immersion Coffee: Cold Brew Is More Floral, and Less Bitter, Sour, and Rubbery Than Hot Brew

“…Perceived sourness then went up with brew temperature as well. We speculate that brew temperature impacts the concentrations of different kinds of acids, as there are many different acids in coffee with varying sensory properties [ 49 ]. Further work with detailed chemical analysis of the acids present is needed to elucidate the reason behind these discrepancies.…”

The analysis of Si/Al ratio on CGA decomposition in Indonesian traditional Kreweng pottery coffee roaster to maximize coffee acidity

“…However, the phenol content is largely depend on the optimal roasting time-temperature profile [21]. Alongside to that, the taste of a coffee is fully depend on the successful palmitic acid decomposition to oleic, linoleic, linolenic, and arachidonic acid which depend only on temperature profile [22]. Even though, every heating tion factor.…”