Which Came First, the Chicken or the Egg?
A recent study published in Nature Metabolism, found a possible explanation of why certain cellular organisms such as Saccharomyces cerevisiae, produce ethanol. According to scientists at the University of Groningen in the Netherlands, the reason may actually lie in the fact that it is a way to slow energy production, sort of like an engine governor. When placed in a nutrient-rich environment, such as those found in wine must, a yeast cell heads into hyper-drive metabolically speaking. When energy production exceeds a certain level, the yeast cells will switch from respiration to fermentation, effectively slowing down energy production.]
This self-regulated “safety cap” on the cell’s metabolic rate means that instead of taking each 6-carbon sugar ring and fully respiring the sugar down to 6 carbon dioxides, we instead get 2 ethanol and 2 carbon dioxide molecules. This is a lot less energy efficient (19 times less efficient) for the yeast cell. . . but this, biologically speaking, may actually be a good thing for the organism. What the scientists theorize is that this excess energy would stir up too much motion within the cell, effectively harming key cellular functions acting within the cell. Meanwhile, ethanol production by yeast has traditionally been viewed as a biological advantage, as ethanol is lethal to many competing organisms. So, the question then is, why did this ethanol-producing mutation occur? Was it for cellular safety reasons or was it for biological advantage? Maybe a little of both — but to read more about the study, visit: www.nature.com/articles/s42255-018-0006-7
Latest Smoke Taint Research
A talk at the Sonoma County Grape Days in February 2019 by assistant professor Dr. Thomas Collins of Washington State University Wine Science Center suggests that smoke taint can occur both pre- and post-veraison. It has been a long held belief that smoke taint is mainly a post-veraison problem, but the latest indications are that it can occur on pre-veraison grapes as well.
Smoke composition has also been shown to play a big role in smoke taint with not all wildfire smoke having the same effects on grapes. Some smoke types seem to have a bigger effect while others can have very little impact. Dr. Collins has been studying the effects of various smoke types and researching some of the key smoke taint compounds for several years now.
Join fellow home winemakers and wine lovers May 16-19, 2019 for our 12th annual WineMaker Conference located in beautiful Traverse City on the shores of Lake Michigan for full days packed with dozens of seminars and special events to help you make your own great wine. The awards dinner for the 2019 WineMaker International Amateur Wine Compeition will be held Saturday, May 18. Sign up today at: https://winemakerconference.com
Entry Deadline for the 2019 Orange County Fair Home Wine Competition. This competition is only open to amateur winemakers who live in California and includes still, fortified, sparkling, dessert, and other fruit/country wines. The cost is $15 per entry. For more information about entering your homemade wines, visit: https://ocws.org/home-wine-competition