Definition of tae kwon do for English Language Learners. : a style of fighting that originated in Korea and that uses kicks and punches but no weapons. Britannica.com: Encyclopedia article about tae kwon do.
It is also used in the baking process as a leavening agent; yeast releasing gas into their environment results in the spongy-like texture of breads and cakes. Because of its role in fermentation, humans have known about and used Saccharomyces cerevisiae for a long time.
Amount of sugar; small quantities (up to 5 Baker's Percent) increases yeast activity. Above 10 Baker's Percent, slows yeast activity. Type of sugar; sucrose, glucose and fructose are fermented rapidly; maltose is fermented slowly; lactose is not fermented at all. pH of dough; optimal pH is acidic 4 to 6. Above, fermentation slows. As yeast ferments, it produces acids to lower the pH to that range.