Brewing Tools

Hop Freshness Calculator

Estimate how much alpha acid your hops have lost based on storage time, temperature, packaging type, and the hop variety's Hop Storage Index (HSI) stability rating.

Hop freshnessAlpha acid lossHSI
Current alpha acid9.53%
Alpha lost4.7%
Freshness factor0.953
Use this much more4.9%
Oxidized alpha / beta0.47% / 0.14%
Hop storage index0.285

Estimate current alpha acids

Hop alpha acids decline as hops oxidize. Storage temperature and oxygen exposure drive most of the loss, so freezer storage and sealed packaging preserve bitterness potential.

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