I was looking at this Q&A, and it got me wondering if there may be value in creating an explicit food/beverage tag. Many of the people here, or new audiences, may be focused on a specific area like that, and have more engagement with a 'higher-intent' tag.
$\begingroup$ Probably should be noted that the question already has 5 tags on it, which is the most tags that a question can have. $\endgroup$– user16Sep 22, 2018 at 13:13
food-beverage is a perfectly adequate tag. However, it's only valuable on questions which are specifically about that industry. In such cases, it informs others about the content of the question and the knowledge which may be required to answer it, since different industries may have different approaches to similar problems.
I would not recommend it, however, for the question you've linked to. Though the OP there mentions modelling beer, the question actually has nothing which is specific to beer or the food and beverage industry. It's just about modelling gas in a still/stirred solution. So, in my opinion, the more general tags currently on the question are sufficient.
Should someone wish to create that tag, they are more than welcome to. Tag creation does not require moderator intervention, merely a user with 150+ rep (or more in graduated sites) to ask a question and add the tag they want.