Ingredient Freshness

In your inventory, every ingredient shows a little “freshness” read. It looks like this:

Curious what that means and where the number comes from? Here's the short version.

Ingredients don't sit still. Hops fade, yeast dies back, grain goes stale. Rather than make you eyeball it, the app estimates how fresh each one still is from three things: what it is, how you store it, and how long it's been sitting. Colder and better-sealed means slower. That's the whole idea.

Hops lose their alpha acids, the part that boils into bitterness. How fast depends on the variety, the temperature, and the packaging. We age them with the Garetz model, straight from the tables in Using Hops. A vacuum bag in the freezer barely moves. An open bag on a warm shelf can shed half its punch in six months, which is why the read shows both numbers, like 5.5% down to 4.1%, with the reason next to it.

Yeast loses living cells from the day it was made. Liquid yeast is the impatient one, dropping about a fifth of its cells every month, so a three-month-old pack is running near half. Dry yeast is far tougher and keeps for ages. Once it's low, plan on a starter. There's more on that in Yeast Starters.

Grain is the odd one. Its sugar potential barely changes until it actually stales, so instead of a curve we just run a shelf-life clock. Whole grain keeps for months, milled grain a lot less, and the fridge or freezer buys you more time on either.

None of this is a best-before date you typed in, and none of it is a lab result. It's a good estimate that updates itself and shows its reasoning. Know better? Enter a measured alpha or a real cell count and the app uses your number instead.