Yes, virtually all juices — whether fresh-squeezed, pasteurized, or from concentrate — should be refrigerated after opening, even if the unopened container was shelf-stable at room temperature.
Why it matters: Many juices (like boxed or bottled apple, orange, or cranberry juice sold in the shelf-stable aisle) undergo processing that allows them to sit unrefrigerated before opening. But once the seal is broken, oxygen and potential microorganisms can get in, and refrigeration slows bacterial, yeast, and mold growth that causes spoilage and off-flavors.
General guidelines:
- Refrigerate promptly after opening, ideally within a couple of hours at room temperature.
- Use within 7–10 days for most pasteurized juices once opened, though this varies by type and preservatives used — check the label for "use by" guidance after opening.
- Fresh-squeezed or cold-pressed juices (unpasteurized) are more perishable and should generally be consumed within 2–3 days of opening, since they lack the shelf-stabilizing heat treatment.
- Store in a sealed container to minimize oxidation and contamination, and keep the fridge at or below 40°F (4°C).
Signs juice has gone bad: off smell (sour, fermented, or "off"), fizzing or bubbling (indicating fermentation), mold, unusual color changes, or a change in taste. If any of these appear, discard it rather than taste-testing to check.
Exceptions: Some shelf-stable juice boxes or pouches (like certain kids' juice drinks) are designed for single servings and don't need refrigeration if consumed shortly after opening — but check the packaging, since guidance varies by brand and formulation.
When in doubt, refrigerating opened juice is the safer default, since the cost of doing so is minimal compared to the risk of foodborne illness or spoiled product.