Ginger Beer Slow Fermentation

[MMBB]

I've brewed a few batches of ginger beer and each time it has taken the yeast a very long time to chug through all of the sugar. I am wondering if it is because I used table sugar as the sweetener or if it is due to acidity from lemons. Each time I've used 5lbs of table sugar in 4g of spring water with the juice from five lemons. I steep the ginger, 8oz of fresh juice in the last batch, along with the lemon juice and the cut pieces of lemons and strain before adding to the fermenter. I used meyer lemons for my last batch to cut down on acidity. I don't currently have a way to test pH.

My last batch had an OG of 1.056 and I pitched S-04 on 2/28/22 and the SG didn't get down to 1.000 until April 7th and it continued to drop to .998 at some point later that month. The battery in my iSpindel died so I don't have a good idea of when FG was actually achieved. I added Fermaid 0 after pitching the yeast, again on March 1st, and another time thereafter (I didn't document the third addition). Temps in the fermenter were around 70 degrees on average but did spike to 73-75 a few times as May rolled in.

Should I switch to corn sugar or maybe add lemon after fermentation? Maybe try a different yeast that is more comfortable in the 70-75 degree range? I'd like to brew this more often but the lead time is crazy. It also takes forever to force carbonate which is a whole different issue.

 

[Miraculix]

I Sense multiple issues here and you basically mentioned them yourself.

The first is the nutrient regime. You don't go that high with your og, so you should be good to not step feed nutrients but throw them in all at once. I would highly recommend the nutrient regime from Staggered Nutrient Addition (SNA) - Mead University — You To Brew which means 6.3 grams of fermaid o per five litres of most, together with all the rest that goes into the mead.

Talking about all the rest, depending on the lemon juice itself and the amount of it, you might be stressing the yeast with really low pH. There are yeasts that can handle low pH better than others and I have no idea in which category s04 falls. US 05 is used a lot for sours, so I guess that one would be a good choice if you want to try another yeast. However, it might be beneficial to wait with the lemon juice up until secondary or at least up until the yeast really started to get going. That way, the introduced oxygen wouldn't matter that much.

Swapping the sugar would not change much if anything at all.