Do Instant Coffee and Herbal Tea Go Bad? How Can You Tell?

Instant coffee and dried herbal tea keep for a very long time without spoiling thanks to their low moisture content, but both can lose flavor and, in some cases, genuinely spoil if stored the wrong way. Telling the two apart matters for deciding whether to actually throw the product out. What should you check in instant coffee?Sound instant coffee is made of free-flowing, separate granules; coffee that has picked up moisture first forms small clumps, and further along it hardens into a solid cake at the bottom of the jar. That hardening alone does not make it unsafe to drink, but it does mean the coffee has absorbed moisture and likely lost much of its flavor. White or greenish fuzzy spots inside the jar are true mold, though, and coffee showing that should not be used. What should you check in herbal tea?Dried herbal tea leaves are normally separate and brittle; leaves that have absorbed moisture stick together and soften, feeling like a soft mass instead of crumbling into flakes when pressed. White or gray fuzzy spots, a smell of wet earth, or a musty odor are clear signs of spoilage in herbal tea; if any of those show up, the tea should not be brewed and drunk. What is the difference between spoilage and flavor loss?Both instant coffee and herbal tea can lose their aroma long before they truly spoil; granules exposed to open air for a long time can keep their color while losing their sharp smell and turning flat-tasting, and herbal tea can fade in color until it is nearly odorless. That state is not dangerous to drink, it just lowers quality; brewing it stronger or using it in another recipe is a reasonable option instead of throwing it away. For both products, storing in a tightly sealed container out of the light slows flavor loss as well as genuine spoilage. Opened instant coffee largely keeps its quality at room temperature for 1-2 years, and opened herbal tea for around a year; past that the product is usually not dangerous but does drop in quality. Drinking moldy herbal tea can cause food poisoning, so a batch showing mold should never be brewed — it should be thrown out. Touching the product with a spoon after opening the jar or bag is also a habit that speeds up spoilage; a damp or wet spoon dipped into instant coffee carries moisture into the rest of the jar and starts the clumping. With herbal tea, not sealing the bag tightly after every use lets moisture from the air slowly work its way into the leaves too. The fridge is not generally recommended for either product; taking the jar or bag out into room temperature can cause condensation to form on the surface, which speeds up the moisture problem. A cool, dry kitchen cupboard is a better storage spot for both than the fridge. When buying, checking whether the granules in a clear jar still look free-flowing, or whether herbal tea leaves look loose and crumbly in the pack, is a simple way to spot products that have been sitting on the shelf too long.