Process Optimisation of Low-caffeine Coffee Using Steam Treatment

Abstract

In addition to being a source of freshener, coffee has an enormous possibility to be developed as a source of antioxidants for functional beverages. However, efforts to increase the value added of coffee as a health functional drink are still hindered by the presence of high level of caffeine, which is thought to have adverse effects on health, especially for coffee lovers who are vulnerable to caffeine. This study aims to optimise the steaming duration to produce low caffeine coffee while maintaining the sensory attributes and antioxidant compounds contained in it. Indonesian Arabica (Leksana variety) green coffee beans were steamed with multi-level steaming durations (0, 20, 40, 60 and 80 min) followed by roasting (medium-dark roast degree), grinding, and brewing (espresso method). The results indicate that caffeine content in the coffee was inversely proportional to the steaming duration. The lowest caffeine content was obtained from the treatment of 80 min steaming with a decrease of caffeine level up to 28.73%. However, the longer process of steaming caused a significant decrease in polyphenol content and antioxidant activity. The hedonic test shows that the steaming treatment of coffee can increase preferences of panellists. There were two driving attributes that influence the overall liking of coffee, namely: bitterness and aftertaste. Coffee obtained from the treatment of 60 min steaming was most preferred by panellists. The results of APLSR biplot mapping show that there was a big change in almost all attributes in the coffee samples after 40 min steaming.

Simultaneous Extraction and Decaffeination Process Optimization of Green Coffee Bean-Based Beverages Using Response Surface Methodology

“…Compared with the raw material, the simultaneous extraction and decaffeination using hot water successfully reduced the caffeine content in decaffeinated green coffee bean powder-based beverages by as much as 14.35 to 30.56 %. This finding is in line with Anggriawan et al [29], who reported that the caffeine content in green coffee beans decreased by 28.20 % than the raw material after the steam pretreatment process. Moreover, this study's caffeine percentage was lower than Sinaga et al [18], who reported decreased caffeine content from 2.6 % in green bean coffee to 1.04 % in decaffeinated green bean coffee using hot water as a solvent, meaning caffeine content decreased by 60 %.…”

“…The mathematical model selection of each response (caffeine content, total phenol, and antioxidant activity (IC50)) of green coffee bean powder affected by the extraction and decaffeination process was listed in Table 4. Based on Table 4, all the observed responses were followed by the quadratic model with a significant model range of 0.0013 to 0.3135 [29]. Solano et al [30].…”

“…Fuller and Rao [35] reported that the dissolution of caffeine into water increased rapidly up to 180 min, then it increased slowly when the time was increased, and a steady state condition occurred at 400 min. Moreover, Anggriawan et al [29] stated that the longer steamed process produced low caffeine content in the final product, which caused the caffeine compounds in the coffee powder lead to leach into the water as solvents.…”

Sensory Assessment of Gayo arabica coffee taste based on various varieties and manual brewing devices

“…The criterion for 'aftertaste' (0.222) in this sensory coffee test shows that the panelists make it the second criterion after 'flavor', as seen on the analysis result of coffee taste criteria assessment in Table 2. 'Aftertaste' is a term used to express the taste left in the mouth and create an experience of preferred coffee taste, where there are two driving attributes that influence overall fondness to the coffee, which are bitterness and aftertaste (Anggriawan et al, 2020). It is necessary to understand that sometimes the same coffee may give a different aftertaste among coffee connoisseurs.…”

Effect in Ultrasound Usage Time on Chemical and Organoleptic Properties of Robusta Coffee Powder (Coffea canephora. L)

“…The steaming process in coffee can increase consumer preference for coffee because it can increase the bitter taste and after taste in coffee caused by reduced caffeine and polyphenol content. The length of the steaming process has a significantly different effect on the taste and color of the coffee [9]. The roasting process aims to get the best color and aroma in coffee, and the longer roasting time can increase bitterness and reduce fruit acidity and sweet taste [10].…”