Tldr: My cider used to be much less sour but now it's coming out
warhead-level. What's wrong? Can K-metabisulfite help?

=====

I've been playing around with cider for about two years now but I've
been intentionally not working from any recipes; rather trying to
discover things on my own. I have an engineering background so I'm
actually more interested in the research-and-experimentation aspect than
the making-a-beverage aspect. I made one batch in August of 2022 that
was just amazing, and I've been chasing that dragon ever since* with
little success.

Here's my process: I use a gallon of Walmart-brand apple juice, with
1/4tsp pectinase, 1/2c white sugar, and 1/4tsp or so of Safcider yeast.
Sometimes, instead of the yeast I'll inoculate with about 1/4c of the
previous batch. I start a batch every two weeks, using 1-gallon plastic
iced tea jugs, capped loosely. I check the SG weekly and stop when the
SG doesn't change by more than a couple thousandths. As I'm checking
the SG I also taste the batch and if there's no sweetness left in it I
add 1/4c white sugar. I want it to run to max abv but still be a little
sweet. This normally takes about 6-8 weeks.

Between batches I rinse everything with very hot water and then store
the containers open end down to dry.

In the early days things came out OK (esp. that one batch!!!) but for
the last six months or so they're all going quite sour.

My suspicion is that I've gotten Lactobacillus into my "equipment" so I
stopped by the brew shop and asked for a good sanitizer to use with
cider; they sold me a packet of potassium metabisulfite. My intention
was to mix up a gallon of this and use it to sanitize everything between
batches, but when I looked it up it turns out folks are using it as an
additive also.

I'm due to start my next batch in a few days (3/15) and I'm unsure what
changes to make. Advice?

=====

*I know what was different about that batch but it's problematic to
duplicate

Crash Gordon <uucp@crashelex.com> wrote:

> Tldr: My cider used to be much less sour but now it's coming out
> warhead-level. What's wrong? Can K-metabisulfite help?
>

You should definitely sterilize everything before use. I always use
an oxygen-based bleach before I start a batch of something. E.g.
sodium percarbonate. Sold as stain remover for laundry use, it comes
in tubs of granules, you use 1 scoop per gallon / 5 litres. (But you
need one of those cheap no-name brands which are made from the
active ingredient with no added perfume etc.) You can also use
chlorine bleach but there's the risk of getting a chlorine smell in
your kit.

I'm surprised you've managed to use ordinary apple juice for cider
at all. As with apple pie, I find you need sour apples, either cider
apples or cooking apples, to get any appreciable flavour.

As the other poster said, metabisulfite is sometimes used at about
1/5 the normal dose to remove chlorine from tap-water prior to
brewing, the idea is that it gets used up by the chlorine and has
basically gone before you add the yeast. At normal strength its
purpose is to actually kill the yeast to halt residual fermentation
in wine, and to help protect the wine from bacterial contamination,
so putting it in water before you start carries a certain amount of
risk that it will stop the fermentation from ever starting. Again,
as the other poster said, it's not a very powerful sanitizer,
bleach is much better and much cheaper!