Thanks for the fun question, Skip! Now that seltzers have been around for a couple of years, brewers have figured out that the best way to make clean bases is to pitch a mixture of nutrient and yeast into whatever sugar substrate is chosen, oxygenate at much higher levels than typically used for brewery fermentations, ferment in a temperature range for the chosen yeast to minimize sulfur and ester production, and then clarify by fining and/or filtration. Today, it’s easy to find yeast/nutrient blends, seltzer-specific nutrients, and yeast strains identified to work well for seltzers on the market. Check out the answer to Joshua Greenberg’s “Wizard” question in the December 2020 issue of BYO for a nice review about the basics of nutrients.
OK, onto your specific question; tips for seltzer? For starters, I would peek at what commercial producers are doing, but not worry about emulating their model for production. And that model is producing a range of packaged seltzers. I’ll get back to this in a moment. My first tip is to master producing a neutral base and coming to grips on what the neutral base represents to the seltzer master. The seltzer neutral base is not really a playground for exploration because the base is a clean source of ethanol sans distillation, and that’s about it. The commercial seltzer master produces these seltzer bases by clean fermentation of a sugar water solution instead of distillation largely because of tax law. It’s also easier to simply produce a clean base by fermentation, perform a few bits of post-fermentation magic, then package.
Things are different at home. For starters, there is nothing preventing homebrewers from making a diluted alcohol solution using vodka and water, then adding flavors to produce a quick and easy seltzer. In fact, if all you want to do is make a tasty and easy seltzer, this method is the ticket. But it doesn’t check that home-fermented box that most of us desire. The other key difference between commercially and home-produced seltzers is packaging. The commercial group wants to sell cans of all sorts of seltzer products. A big chunk of homebrewers love skipping the small pack and sticking with kegs.
I think your creativity should be focused on what happens to a neutral seltzer after successfully filling a keg with clean and clear seltzer. Instead of producing one batch of seltzer at a time like you do with beer, focus on producing tinctures, syrups, shrubs, etc. that you will add to your clean seltzer. Not much different to how Berliner weisse is tweaked upon serving or how Torani syrups are used to produce Italian-style sodas by dosing into sparkling water. This is where homebrewers have a clear advantage over commercial producers. No branding, no special packages, and no fancy tap handles mean that you can convert your clean seltzer into a huge range of different products right when you pour a glass.
The creative part of this process is making the special sauces used to deliver the complexity of flavor and color you desire. This may not seem like the most groundbreaking bit of advice, but I think it’s solid, and I am sticking to it!