Morning, all. I have a few hours of recipe testing ahead of me, so let’s just cut to the chase:

1. Today’s Food section! Read it!

2. Today’s Free Range chat! Join it!

3. Today’s Chat Leftover! Memorize it!

Okay, I didn’t really mean that last one. I just think things read better in groups of three. Here’s this week’s question, an unanswered straggler from last week’s chat:

The gin rickey recipe from last week sounds like it would hit the spot in our hot weather. The recipe calls for mineral water. Would you mind explaining the difference between mineral water, club soda and seltzer? They all seem very similar to me.

And so they are, grasshopper. So they are. Here’s the scoop.

Mineral waters, once drunk chiefly for medicinal purposes, contain naturally dissolved minerals and come from wells, natural springs and other underground sources. They can be fizzy or not. The minerals are said to impart distinctive flavors to the water — sort of like terroir with wines. To be labeled mineral water, a product must contain at least 250 parts per million of what the FDA calls “dissolved solids.”

Club soda, which is sometimes called soda water, has been artificially carbonated to make it fizz. It also contains bicarbonate of soda, an alkaline substance that can help neutralize stomach acid. It’s very similar to seltzer, which is also artificially carbonated. In its pure form, seltzer water is tasteless, but in recent years flavored seltzers have become common. For practical purposes, club soda and seltzer water are interchangeable as mixers for all but the most picky palates.

The FDA regulates, monitors and inspects all three kinds of water. It considers mineral water to be a bottled water, and it considers club soda and seltzer to be soft drinks.

How did I know all this? I didn’t. For help, I turned to the Food section’s information bible, otherwise known as The New Food Lovers Companion, which exists in well-thumbed volumes on staff members’ desks here. I also checked the FDA’s Web site. And now, on to the recipe tests. I’m expecting great things from some flounder.