Production of Higher Alcohols During Indonesian Tapé Ketan Fermentation

Abstract

A study was made of the higher alcohols (fusel oils) produced during the Indonesian tape ketan fermentation using Amylomyces rouxii as the principal mold, alone or in combination with yeasts belonging to genera commonly found in the tape ketan fermentation (Endomycopsis, Candida, and Hansenula). Total fusel oils increased with length of fermentation. Fusel oils detected in the product distillate included isobutanol and isoamyl and active amyl alcohols. No n-propanol was detected. Isobutanol and isoamyl alcohols were formed in the largest amounts. A. rouxii alone produced nearly the same quantity of fusel oils (total production, 275 mg/liter at 192 h) as it did in combination with Endomycopsis burtonii (total production, 292 mg/liter at 192 h). A. rouxii and Endomycopsisfibuliger produced fusel oils totaling 72 mg/liter at 32 h and 558 mg/liter at 192 h. A. rouxii in combination with Candida yeasts produced somewhat more fusel oils, ranging from 590 to 618 mg/liter at 192 h. A. rouxii in combination with Hansenula yeasts produced the least fusel oils, totaling 143 to 248 mg/liter at 192 h. During the first 36 h, production of fusel oils was higher at 30 and 35°C than at 25°C. At 48 h fusel oil production was slightly higher at 30°C than at 35°C. Beyond 48 h, production of fusel oils was higher at 25°C. A. rouxii in combination with Hansenula anomala and Hansenula subpelliculosa produced considerable ethyl acetate, ranging from 145 to 199 mg/liter at 36 h and 354 to 369 mg/liter at 192 h.

On-Package Color Indicator for Ripeness Monitoring of tape ketan Packaging

“…Meanwhile, the alcohol content in TK increased day by day during fermentation and was found as high as 4.6% (v/ v) after 7 days (Figure 3(c)) as also reported in reported in literature [25] . Figure 3(c) shows that the indicator follow similar trend till the TK ripe and vary from the alcohol response, when TK in the ripe and overripe stages.…”

“…Humidity inside TK packaging has mainly resulted from the equilibrium between water contained in the TK and its headspace inside packaging since the headspace outside the packaging is not much affected due to the TK stored in tray with lit that has very limited or very low of water vapor transmission rate so that humidity outside packaging can be neglected. When alcohols are produced, by sugars metabolism without oxygen with the yeasts via fermentation process [25] , the color indicator starts to change to blue as water vapor also produces, and humidity inside packaging starts to increase drastically.…”

The Potential of Glutinous Rice Tape Added with Lactobacillus plantarum Dad-13 and Saccharomyces boulardii as a Probiotic Food

“…Utaminingdyah et al (2022) reported that tape from various types of rice (nonglutinous) inoculated with Lactobacillus plantarum Dad-13 produced lactic acid levels, acetic acid, and ethanol, respectively, at 0.21-0.53%, 0.14-0.35%, and 0.81-0.91%. Cronk et al (1979) showed that Amylomyces rouxii, separately or in combination with different yeasts, yielded a higher range of alcohols, including isobutanol (2-methyl-1propanol), 2-methyl-1-butanol and isoamyl alcohol (3-methyl -1-butanol).…”

Sensory Profiles and Lactic Acid Bacteria Density of Tape Ketan and Tape Singkong in Bogor

“…The production of glucose, lactic acid, and ethanol gives a bit of alcohol taste and sour-sweet taste. Cronk et al (1979) stated that A. rouxii, with or combined with a different yeast, produces various kinds of alcohol in higher amount, including isobutanol (2-methyl-1-propanol), 2-methyl-1-butanol and isoamyl alcohol (3-methyl-1-butanol). Each of the alcohol type has different sensory characteristics, however, the concentration which can influence the sensory characteristics is not yet known.…”