Fermentation is an important process in the creation of food products. The process also generates biofuels and many pharmaceuticals.
In a new study by the University of Florida, scientists chose to analyze beer yeast fermentation. Through this study, scientists wanted to know the behavior of fermented yeast in outer space.
Even if it sounds trivial, the study’s concept has far-reaching applications.
Study author Andrew MacIntosh, a UF/IFAS associate professor of food science, said, “We are absolutely going to be conducting fermentations under Microgravity in the future as we continue space exploration, and there are going to be outcomes that will be very difficult for us to predict. It’s essential that we look at what some of those outcomes may be now so we can decide which processes are going to be the first ones we perform under Microgravity, how we adapt them, and how we can take advantage of the changes we see.”
Under the guidance of Pedro Fernandez Mendoza, the team used barley grown in Live Oak, Florida, and turned it into wort, a liquid solution of extracted grains. They then divided the wort into six identical samples. By combining the samples in tubes with Saccharomyces pastorianus, the team started the fermentation process. Saccharomyces pastorianus is the species of beer yeast used for brewing lagers.
Three tubes were kept as controls, while the other three were put in a clinostat, a machine that simulates low gravity by spinning the samples.
Scientists noted, “Microgravity did not adversely affect the number of yeast cells or their viability. Instead, the rate of fermentation increased. They attributed this result to the cells’ constant suspension, which maximized nutrient availability by preventing settling.”
Scientists found that when exposing yeast to Microgravity, fewer esters are produced. Esters are fermentation’s byproducts that create desirable and undesirable beer flavors.
Along with suspension, a yeast gene that regulates ester production was found to play part; the gene was expressed less in yeast samples exposed to Microgravity than in control samples.
Journal Reference:
- Pedro Fernandez Mendoza, Katherine Witrick, Skylar Moreno and Santiago Cardenas Pinto. Brewing Beer in Microgravity: The Effect on Rate, Yeast, and Volatile Compounds. DOI:10.3390/beverages10020047