Q: Why does my siphon coffee taste sour in summer?

In summer, your kitchen is warmer, which can make your water boil more aggressively and heat up your grinder, causing inconsistent grinds. That often leads to under-extraction—the water doesn't pull enough sweetness out of the beans, leaving sour acids behind.

Q: Should I change my grind size when it's hot?

Yes. If your coffee tastes sour, grind slightly finer. This increases surface area so water extracts more evenly and quickly. But go step by step—a big jump can make it bitter.

Q: How much coffee should I use for siphon in hot weather?

Try adding 5-10% more coffee. For example, if you normally use 20g per 300ml, try 21-22g. More coffee buffers against sourness, but don't overdo it or it'll taste harsh.

Q: Is it safe to drink sour siphon coffee?

It's safe to drink, but it's not pleasant. If the coffee smells or tastes sharply acidic or fermented, it might be spoiled—especially if beans were stored poorly in heat. When in doubt, throw it out.