Chili

Chili keeps 3–4 days refrigerated and 2–3 months frozen — and it is one of the better leftovers, since the flavor genuinely improves after a day.

Cool it quickly. Chili is thick and dense, which makes it slow to cool, so divide it into shallow containers no more than two inches deep and refrigerate within two hours. Do not put a full stockpot in the refrigerator.

Chili freezes exceptionally well. Portion it flat in freezer bags so it stacks and thaws quickly. The beans and meat both hold up; only dairy toppings need to be added fresh.

Reheat to a full boil, stirring. If you are keeping chili warm for a party, hold it above 140°F in a slow cooker on high rather than on the warm setting, and do not use a slow cooker to reheat cold chili — it passes too slowly through the growth range.

Chili has two things working in its favor and one working against it.

In its favor: acidity from tomatoes, at a pH usually around 4.5–5.0, which is low enough to slow many bacteria meaningfully. And a long simmer, which is a thorough kill step for vegetative cells.

Against it: chili is thick, dense, and cooked in large batches, which is the profile that suits Clostridium perfringens. Its spores survive the simmer, the oxygen-poor interior of a heavy pot is what it prefers, and slow cooling through 125–70°F gives it the conditions to multiply rapidly. Meat chili in a big pot cooled on a counter is close to the canonical scenario for it.

Beans add a second consideration, though mainly for dried beans rather than canned: raw or undercooked kidney beans contain phytohaemagglutinin, a lectin that causes acute nausea and vomiting. It is destroyed by boiling for at least ten minutes, but slow cookers do not reliably reach that temperature — dried kidney beans must be boiled hard before going into a slow cooker. Canned beans are already cooked and pose no such risk.

Spoiled chili smells sour or fermented rather than rich, may fizz or bubble cold, and develops a slimy texture or surface mold.