Food preservation in Project Zomboid

Every perishable item has two timers: days until it turns stale and days until it turns rotten. Each one ages at a rate set by the Food Rot Speed sandbox option, and cold storage slows it further. Sealed cans and dry goods usually have no timer at all. See the food list for any item's numbers.

The stage penalties above come from 42.20 data (one source), and that source notes that older tables with different values do not match current builds. Rotten food also restores less hunger. The Iron Gut trait lowers the chance of getting sick from it.

These are base values before sandbox and fridge modifiers. Cooking a raw item usually does not reset its timer. Rice and pasta pots are the exception, because the pot is a new item. With high Cooking skill you can add a small share of rotten ingredients to a dish: about 5% at level 7 and 10% at level 9 to 10.

A powered fridge makes food age at about one fifth of the normal rate, so food lasts roughly five times as long. Food that is fully frozen (the name reads "Frozen") does not age at all until it thaws. Sources disagree about the freezer before food is fully frozen: one says it acts like a fridge until the item freezes, another describes the freezer compartment as about 25 times slower. Either way, the useful state is fully frozen. The sandbox Fridge Factor option changes how strong this effect is, so check your sandbox settings.

Without power a fridge or freezer is just a box. It does not slow aging and it does not freeze anything. One source says that since 42.21 appliances warm up gradually on the day the grid fails, so food does not spoil the moment the lights go out (one source). The same source says food in a bag inside a fridge is now chilled properly.

A generator keeps cold storage running after the power shutoff, at the cost of steady fuel. A fridge on generator power draws about 0.008 to 0.013 liters per hour (one source).

Opinion In a cold winter, an unheated room or an outdoor crate can stand in for a freezer, but test it with a single item before trusting a whole hunt to it.

Jarring is the main vanilla way to keep a harvest without power. In Build 42 you must learn the recipe first: read the American Homesteading magazine or reach Cooking 8. Find the magazine in the usual places listed on the magazines page. Build 41 guides often assume the recipe is known and list sugar in the brine. Neither is true in Build 42.

Crops that can be jarred include bell peppers, broccoli, cabbage, carrots, eggplant, leeks, potatoes, radishes and tomatoes. One source also lists fish roe. After sealing, cook the jar on a heat source (about 60 minutes); an uncooked jar spoils at the normal rate.

Shelf life is disputed. Two sources give 60 days fresh plus 30 days stale. Another, written for 42.19, says 30 days fresh and fully rotten at 60. Write the date on your jars in your head and check the tooltip.

Lids and vinegar run out first. Vinegar has no crafting recipe in vanilla Build 42, so loot grocery stores, restaurants and kitchens for bottles and jugs. New jars can be made by glassmaking at level 5 (one source). Grow the crops on the crops page with jarring in mind.

Build 42 added drying racks, but in vanilla they dry plants, not meat. There is no confirmed vanilla recipe for drying or smoking meat or fish, and no recipe for salting meat. Salt is used as a jarring ingredient. Beef jerky exists and never spoils, but it is loot only; no recipe makes it. Mods add meat racks and smokers, but they are not part of the base game.

One source says a large rack takes 1 to 20 units at a time and needs about two in-game days per batch (one source). This matters for farming rather than meat. For a big kill from hunting, fishing or butchering, your choices are to eat or cook it fast, freeze it, or share it.

Some foods have no spoilage timer while sealed. These are the core of any stockpile. Open them only when you are about to eat, because an opened can lasts about as long as raw meat.

Store the stockpile in your base's storage, away from the fridge, and keep track of nutrition, since a diet of pasta alone leaves you short on protein and fat.

The grid fails at a time set in sandbox options; the shutoff page covers the timing. Start this plan as soon as the first week is under control.

1. Fill the pantry early. Loot every can, bag of rice and pasta, and all vinegar, salt, jars and lids you find.
2. Learn jarring. Look for American Homesteading in bookstores and homes, or keep cooking toward level 8.
3. Eat from the fridge first. Fresh meat, milk and fruit go before anything sealed.
4. On shutoff day, triage. Cook all raw meat that day, jar any vegetables before they turn stale, and eat the rest.
5. Decide on a freezer. Only run one on a generator if you have a reliable fuel supply.
6. Plant for storage. Potatoes, cabbage and carrots either keep well or jar well.

Opinion Most players do better treating the freezer as a short bonus and the pantry as the real plan. Fuel runs out; cans do not.