Check each type of store on a fixed schedule for the signs that matter, such as warm spots and musty smell in grain, soft or sprouting roots, swollen or leaking canned lids and slime on cured meat, and respond by removing the spoiled item at once, checking its neighbours, finding the cause and recording it. Suspect canned food is destroyed untasted, and mouldy grain, rotten produce and green or heavily sprouted potatoes are not used as feed.
Spoilage monitoring is the routine inspection of stored food for early signs of rot, mould, pests and heating, with a fixed response when a sign appears.
Look Early And Look Systematically
The carrier says to check the root cellar weekly in November and to remove any spoiling produce, and that one rotten potato can destroy a bin. Spoilage spreads from a first item to its neighbours, so the aim is to find it while it is one item.
What To Look For, And What To Do
| Store | Signs | First response |
|---|---|---|
| Grain | Warm spots, musty or sour smell, caking or clumping, insects, webbing, moisture on the bin wall | Probe with a thermometer; open and turn the heap; dry and sieve if only damp; discard grain with visible mould |
| Roots and cabbages | Soft spots, weeping, mould, sprouting, shrivelling | Remove the item and any it touched; wipe the bin; check temperature and humidity (Temperature and Humidity) |
| Canned goods | Bulging or leaking lid, hissing or spurting on opening, cloudiness, off smell | Treat as unsafe and destroy |
| Cured and smoked meat | Slime, sour or rancid smell, discolouration deep in the meat | Discard if in doubt; check cure and cellar temperature |
| Dried foods | Damp, clumping, mould, insect frass | Dry again if only damp; discard if mouldy |
| Fermented foods | Fuzzy mould, putrid smell, long periods too warm | Discard (Safety and Troubleshooting for Fermentation) |
For grain, safe moisture depends on the grain and the time kept; the existing guides give figures that differ between wheat and oats, so check the grain guide for yours (Grain Storage).
Why Grain Heats
Damp grain supports mould and insects, which respire and give off heat. Heat dries the top and drives moisture to cooler parts, so a hot spot can grow inside the heap before anything shows on the surface. A thermometer probe in the bin reveals the hot spot early. Dry the grain, turn it to cool it, and screen out clumps (Moisture and Pest Control).
What May Go To Animals
The carrier says to use partial spoilage as animal feed. That is safe for sound but bruised produce that has been trimmed. It is not safe for:
- Mouldy grain, nuts or bread. Moulds can produce mycotoxins, which cooking does not destroy and which also poison livestock.
- Rotten produce with spreading soft rot.
- Green or heavily sprouted potatoes. They contain glycoalkaloids (solanine and chaconine) that poison people and animals; cut sprouts and green skin off potatoes meant for the table, and discard any that are mostly green or taste bitter.
- Suspect canned food. The canning guide says not to feed it to animals either (Canning & Pressure Preservation).
Response Protocol
- Find the spoiled item or the hot spot.
- Remove and isolate it, and anything touching it.
- Check the neighbours on every side and below.
- Decide: use today, reprocess, trim, feed (only where allowed above) or discard. If in doubt, discard.
- Find the cause: too warm, too wet, a hole, a pest, damaged items loaded, a failed seal.
- Clean the bin or shelf and let it dry.
- Record the date, item, amount and cause in the inventory (Monthly Inventory Checks).
Measure The Loss
Loss rate = amount lost ÷ stock at the start of the month. Worked example (invented numbers to show the sum): 18 kg lost from 900 kg of potatoes is 18 ÷ 900 = 2.0% in the month. Set an alarm level for each store from your first winter’s records; a figure that climbs from month to month points to a cause that has not been found.
Spoiled stores can hurt the people who handle them
Canned food that bulges, leaks or smells wrong may carry botulism toxin, which can be fatal: do not taste it, do not feed it to animals, and wear gloves when destroying it. Mouldy grain and hay give off spore dust that can damage the lungs, so wear a cloth mask and work in the open air. Never enter a grain bin or a closed cellar alone; a bin can bury a person and a cellar can lack oxygen (Root Cellar Loading Plan).
Common Mistakes
- Waiting for the smell. By then it has spread.
- Feeding anything spoiled to animals.
- Throwing out one jar and ignoring the batch. A failed seal may point to a bad lid lot or a process error.
- Not recording the cause. The same fault recurs.
What’s Next
- Learn next: Storage Rotation & Inventory — the routine around it
- Combine with: First-in-First-out (FIFO) Systems — using the vulnerable stock first