Safe Holding Times in Store for Crops Before Drying
6 August 2025With harvest in progress and potentially a backlog to drying grains, here is guidance on the maximum safe storage durations for combinable crops between harvest and drying. Holding crops at high moisture levels without timely drying or cooling can lead to spoilage, loss of germination, reduced alcohol yield, or rejection at intake. The information below outlines crop-specific safe holding periods based on moisture content and ambient temperature, with a particular focus on premium crops such as malting barley and distilling wheat.
Maximum Safe Holding Time Before Drying (Days)
| Crop | Moisture Content (%) | <15°C | 15–20°C | >20°C |
|---|---|---|---|---|
| Feed Wheat / Feed Barley | ≤13.0% | 60+ days | 30–60 days | 15–30 days |
| 14.00% | 30–45 days | 15–30 days | <15 days | |
| 15.00% | 14–21 days | 7–14 days | <7 days | |
| 16.00% | 7–14 days | 4–7 days | 1–3 days | |
| ≥17.0% | <7 days | 1–5 days | <1–2 days | |
| Distilling Wheat | ≤14.0% | 45–60 days | 30–45 days | 15–30 days |
| 14.50% | 21–30 days | 10–20 days | <10 days | |
| 15.00% | 7–14 days | 4–7 days | 1–3 days | |
| ≥16.0% | <7 days | 1–3 days | <1 day | |
| Malting Barley | ≤13.5% | 30–45 days | 15–30 days | 10–20 days |
| 14.00% | 14–21 days | 7–14 days | <7 days | |
| 14.50% | 7–10 days | 3–7 days | 1–3 days | |
| 15.00% | <7 days | 1–3 days | <1 day | |
| Oilseed Rape | ≤8.0% | 60+ days | 30+ days | 20–30 days |
| 9.00% | 14–21 days | 7–14 days | 3–7 days | |
| 10.00% | 7–10 days | 3–7 days | 1–2 days | |
| ≥11.0% | Unsafe | Unsafe | Unsafe | |
| Field Beans | ≤15.0% | 60+ days | 30–60 days | 15–30 days |
| 16.00% | 14–21 days | 7–14 days | <7 days | |
| 17.00% | 7–10 days | 3–7 days | 1–2 days | |
| ≥18.0% | <5 days | 1–3 days | <1 day |
Key Storage Risks by Crop
| Crop | Primary Risk | Mitigation |
|---|---|---|
| Feed Wheat / Barley | Fungal spoilage, insects | Dry to ≤14.5%; cool to <15°C |
| Distilling Wheat | Starch degradation, mycotoxins | Dry ≤50°C; store <14.5% moisture |
| Malting Barley | Loss of germination | Dry gently ≤40°C; store <14% moisture |
| Oilseed Rape | Self-heating, rancidity | Dry to ≤8%; monitor temperature; shallow fill |
| Field Beans | Surface mould, splitting | Dry slowly; cool below 14% |
Best Practice Recommendations
- Harvest Moisture Targets: Feed Wheat ≤15%; Distilling Wheat ≤14.5%; Malting Barley ≤14%; OSR ≤9%; Beans ≤16%.
- Drying: Avoid temperatures >40°C for malting barley, >50°C for distilling wheat. Use slow, even drying.
- Cooling: Cool grains to <15°C within 2 weeks, and <10°C for long-term storage. Use ambient air cooling.
- Monitoring: Weekly moisture/temperature checks post-harvest. Check for odours, heating, condensation.
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