Once opened, Soy milk keeps about 7–10 days in the fridge. Unopened, it keeps about Until the package use-by date.
That's the longest window published for Soy milk — opened in the fridge is its best case.
| Situation | Keeps for |
|---|---|
| Unopened · fridge | Until the package use-by date |
| Opened · fridge | 7–10 days |
Air and warmth are what shorten an opened item's life — the right container buys back the days the packaging gives up once the seal's broken.
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About 7–10 days refrigerated at 40°F (4°C) or below, according to USDA FoodKeeper v128. Refrigerate it once it's open.
Yes — keep Soy milk at 40°F (4°C) or below once it's open. Refrigerate at 40°F (4°C) or below.
Look for: Sour or off smell; Mould or fuzzy spots; Curdled, slimy, lumpy, or separated texture; Yellowing or other discoloration. Those are the general signs for dairy & eggs — USDA FoodKeeper v128 publishes no spoilage note for Soy milk specifically. Never taste something to test it — when in doubt, throw it out.