Responding to Subhash Arora’s article, ‘An Enduring Myth: Wine, Vinegar & Serving Temperature’ (delWine, August 8), the James Beard award-winning writer and author of the forthcoming book Red, White, and Drunk All Over, Natalie MacLean, comments:

“Fascinating article about wine temperatures and vinegar! I have heard conflicting statements about leaving wine out (uncorked, say in a glass): Does it actually turn to vinegar eventually or just oxidise completely (or does complete oxidation result in vinegar) enjoy your newsletters!”

Arora says: Vinegar is the end-product of fermentation. When wine is exposed, the alcohol in it gets transformed into acetic acid by the bacteria present, which requires oxygen to grow faster.

Wine stored at higher temperatures will usually taste cooked, jammy and ‘maderised’. Temperature variations from day and night will cause the wine to expand and contract, forcing oxygen to enter the sealed bottle when stored for longer periods and convert it into acetic acid (vinegar).

My article, though, focused more on storage rather than the serving temperature changing wine to vinegar. Wine in the open glass will also turn into vinegar eventually due to the action of the bacteria.

I am a frequent visitor to your web site, www.nataliemaclean.com, and I know many people who enjoy reading your informative newsletter, Nat Decants.

Reacting to the same article, Avtar Singh Sandhu of Mushal Winery (Sonoma County, USA) says: “I also picked up on the error in reporting or the statement of Aman Dhall in Brunch. You have correctly said that it is ‘storage’ and not the ‘serving’ temperature that turns wine into vinegar (High School Chemistry!). The next lot of Mushal’s wines will have a back label recommendation for storage. I feel it is essential to have an informed public.”

Sandhu has also sent a chart showing how wine degenerates as the temperature goes up. Suppose the storage temperature rises from the ideal 13°C to 23°C, the wine will age at a faster rate of 210% to 800%. The deterioration factor that converts wine into vinegar also speeds up at the same rate.

The big question for us: What happens if storage temperatures go up to 33°C or more, which is what happens at most Indian houses and stores? We shudder at the thought.