Cold brewing coffee results in a sweet taste with high intensity and less bitterness and sour notes. The temperature and roasting time of the equipment used can impact the flavor of the coffee. A study was conducted to evaluate cold brewing processes on Arabica coffee samples obtained from different roasting treatments. The study found that the best treatment for roasting was a temperature of 190oC with a roasting time of 10 minutes. The cold brewed coffee had high acidity intensity, a clean aftertaste, a light brown color, and a light body. The results suggest that the roasting temperature and time are significant factors in producing high-quality cold brew coffee.

A recent study focused on identifying key factors in the brewing of coffee that consistently impact the final product. The study examined grind size, roast type, steep time, grind-to-water ratio, and temperature in samples prepared using a French press technique. Using an automatic temperature compensation refractometer and statistical analysis, the study found that total steep time, grind-to-water ratio, and roast type were the most significant factors affecting total dissolved solids in the coffee. Further experiments determined that the ideal combination of factors for a target %TDS of 1.26 is a medium roast coffee ground fine with a 0.08 grind-to-water ratio, initially heated to 195 Fahrenheit, and steeped for 7 minutes in a French press. The study is unique in its focus on the impacting factors across all methods of extraction, rather than on extraction methods themselves. These findings are relevant for the food industry, as they provide useful guidance for the brewing of coffee regardless of the specific method used.

A study conducted in Karawang Regency, West Java aimed to determine the effect of roasting temperature on chemical content of coffee beans at various fruit maturity. The chemical content observed were water, caffeine, fat, chlorogenic acid, and ash before and after roasting. The results showed that the ripe coffee bean with roasting temperature of 210°C is the best, which gives the lowest yield. The unripe green beans have the highest water content. The roasting temperature did not provide a significant difference in fat, caffeine, chlorogenic acid, and ash content. Organoleptic test results showed that the mature beans with roasting temperature of 200-210°C were the most preferred, while the coffee brew most preferred was overripe bean with the roasting temperature of 200°C. These findings are important for coffee bean roasters to take into account the optimal temperature for roasting based on fruit maturity and desired taste preferences.

Roasting is a crucial step in the production of coffee that determines its aroma and flavor. The Hot Air Roasting method, introduced by Michael Sivetz, a chemical engineer and coffee industry consultant, is a different method that changes the structure and chemical properties of coffee beans through the pyrolysis process. The longer the roasting process, the weight of coffee will decrease due to the decrease in water content in coffee beans. Hot air roasting machines, which use electric energy, are efficient and can produce the best results for brewing robusta coffee at 200°C in 15-20 minutes. The inverse relationship between temperature and density of coffee is crucial in obtaining the best roasting results. It is important to note that even high-quality coffee beans cannot have maximum aroma and flavor if the roasting process is not done properly. Therefore, selecting the right type of coffee and using the appropriate roasting method are essential in producing high-quality coffee. Overall, the Hot Air Roasting method can be a suitable option for producing robusta coffee with good aroma and taste.

A study aimed at identifying and characterizing the bioactive and aromatic compounds in cold brew coffee has found that the drink is an exceptional source of chlorogenic acid. This makes it a potential substitute for energy drinks with fewer controversial additives. The study, which used headspace solid-phase microextraction and GC-MS and LC-MS analysis, investigated cold brew coffee extracts prepared using different green bean roasting profiles and varying extraction temperature and time parameters. It found that chlorogenic acid levels can be increased to above 900 mg/L or maintained at a similar level of 400–500 mg/L with caffeine. This presents the possibility of diversifying beverage production at an industrial scale. The study also identified aroma compounds responsible for fruity or caramel–roasted-almond notes, with the best option for cold brew coffee production being beans roasted in the 210–220 °C temperature range. The findings suggest cold brew coffee could change consumer purchasing decisions and create a new, natural alternative to energy drinks.

A recent study has found that the sensory quality of coffee, including its taste and aroma, significantly influences consumer acceptance. Using a Taguchi orthogonal array L9 design, the study tested the effects of postharvest treatments (full wash, honey, natural), roasting temperature (150, 175, and 200ºC), roasting time (10, 12.5, and 15 minutes), and milling (80, 100, and 120 mesh) on the sensory qualities of ground and brewed Robusta coffee. The study found that postharvest and processing treatments significantly influenced most of the sensory qualities of the samples, and that the best combination of treatments for optimal acceptance was postharvest honey, a roasting temperature of 175ºC for 15 minutes, and a sieve size of 80 mesh. The study’s findings underscore the importance of understanding how various postharvest and processing techniques can enhance or detract from the sensory qualities of coffee and how that, in turn, can impact consumer acceptance. By identifying the best postharvest and processing techniques for Robusta coffee, this research could help inform the production practices of coffee farmers and others in the coffee industry, leading to more consistent, high-quality products that meet the needs and preferences of consumers.

4 2019 Regional Identity of Hops starting point, but one should remember that hops are a very different crop, so the same variables may not be as useful for defining hop terroir. There is growing evidence that regional differences in hop chemistry and consumer-detectable aroma hop characteristics may exist, at least at the national and global levels.

A new study has found that the dominant hot beverages served in Brazil’s most popular low-cost food service establishments and coffee shops are served at temperatures that are likely to cause cancer. The International Agency for Research on Cancer has classified the consumption of “very hot” beverages as “probably carcinogenic to humans.” However, there has been no information available previously regarding the serving temperature of Brazil’s most commonly consumed hot beverage, coffee. The study found that the average serving temperatures of all beverages were on average 90% and 68% above 65 °C in the low-cost food service establishments and coffee shops, respectively. This is well above the recommended temperature level, leading the authors to conclude that consumers should allow a minimum cooling time before drinking of about two minutes at both locations. The best-selling coffee beverages in the low-cost food service establishments consisted of 50 mL shots of sweetened black coffee served in disposable polystyrene cups from thermos flasks, whilst in the coffee shops, 50 mL shots of freshly brewed espresso served in porcelain cups were the dominant beverage.

Researchers have found that activated carbon made from brewed coffee has a high adsorption capacity due to its high porosity, and this could be useful for various adsorption applications. The study looked at the manufacture of activated carbon in one step of carbonisation and activation in the same reactor and furnace. The sample was carbonised at 650°C and then immediately activated using nitrogen, resulting in activated carbons marked as K-A30, K-A60, and K-A90, for activation holding times of 30, 60, and 90 minutes respectively. K-A30 demonstrated the best pore structure of the three, with the highest nitrogen adsorption capacity, pore surface area, and pore volume, and an average pore diameter of 1.915 nm. K-A60, however, had the highest fixed carbon content of 71.67%. The research is significant because it shows that brewed coffee can be used to make activated carbon with desirable pore structure characteristics that could be useful in various applications.

Instant coffee powder is a popular drink that is produced through either freeze-drying or spray drying. However, the latter has shown advantages in terms of shorter drying time, ability to handle large quantities and continuous production. The study aimed to identify the factors affecting the quality of coffee production in the spray drying process. The initial coffee extract concentration between 30-42 wt.% was fed through the atomizer with an inlet air temperature of 423.15 K to 573.15 K, and a pressure of 52 bar. The simulation results showed that the best conditions for drying coffee were an air temperature of 423.15 K, a pressure of 52 bar, and an initial extract concentration of 42%. The velocity and vapour concentration distribution flattened as the flow moved downstream, resulting in almost uniform moisture distribution in the drying air leaving the chamber. This research provides insight into optimizing the spray drying method for coffee production, ensuring the best quality for consumers.