Comparison of Temperature Effects on Brewing of Makgeolli Using Uncooked Germinated Black Rice

Abstract

1) In this study we investigated the effect of temperature on the two-stage fermentation of Makgeolli using uncooked germinated black rice. The fermentation processes were conducted at 15℃ for three weeks and 25℃ for 7 days. The pH of Makgeolli at 25℃ increased from pH3.0 to pH 4.2, which was consistent with that at 15℃. In contrast total acidity of Makgeolli at 15℃ was about half of that at 25℃ (0.36% and 0.59%, respectively). By the 7 days-fermentation at 25℃, 11% of alcohol was produced, whereas three weeks were required for the same alcohol production at 15℃. In the case of sugar contents, the amounts of total glucose-equivalent reducing sugars and glucose increased at the end of the fermentation at 25℃ up to 2.25 mg/mL and 3.4 mM, respectively, whereas those at 15℃ were maintained at very low levels (0.18 mg/mL and 0.1 mM, respectively). Such limited supplement of sugars at 15℃ seemed to affect metabolism of yeast, resulting in different composition of organic acid. At 25℃, citric acid that was 73.4 ppm at the initial fermentation was consumed completely, whereas 20 ppm of citiric acid was remained at 15℃. In addition, acetic acid and lactic acid in Makgealli at 15℃ were 53% and 14% of those at 25℃.

Philippine rice wine (Tapuy) made from Ballatinao black rice and traditional starter culture (Bubod) showed high alcohol content, total phenolic content, and antioxidant activity

“…Compared to the local red rice and non-pigmented rice, Ballatinao black rice had the highest anthocyanin content, total phenolics, crude protein and crude fat (Romero et al, 2012). Black rice varieties generally have high anthocyanin content (Hou et al, 2013), and several countries in Asia are exploring this feature to produce rice wine with high antioxidant activities, including India, Japan, Korea, China, Thailand, and Cambodia (Chay et al, 2020;Jiang et al, 2020b;Kim et al, 2012;Moirangthem et al, 2020;Singkong, 2015;Takeshita et al, 2015). In the Philippines, Ballatinao black rice is already used in Tapuy making, but to our knowledge, no studies have been done describing the use of this black rice variety in Tapuy production.…”

Quality characteristics and antioxidant activities of Korean traditional rice and quinoa‐based wine “Makgeolli”

“…Makgeolli has thus been widely recognized as a healthy alcoholic beverage globally. Studies of Makgeolli prepared the beverage using various grains, including black rice (D. R. Kim et al, 2012), brown rice (C. H. Baek et al, 2013), and barley (Park et al, 2015). In addition, Makgeolli has been prepared with the addition of various fruits and vegetables, including citron (Yang et al, 2011), pear (Lee et al, 2009), pomegranate (Kim & Eun, 2012), and blueberry (Jeon & Lee, 2011).…”