Cooling without electricity: the principles

In short

• Bacteria multiply fastest between 5 and 60 °C (40–140 °F). Cooked food stays out no more than 2 hours, and above 32 °C (90 °F) 1 hour.
• Raw meat, fish, offal, milk, fresh cheese and cooked dishes with meat need 0–4 °C (32–40 °F). A well, a spring and a cold larder give 8–15 °C in summer: that is not a fridge.
• Without electricity, cold comes from the ground, water, evaporation, night air and ice. Only ice gives 0–4 °C in summer.
• A thermometer is a must. A place is "cold" only once you have measured it at 3 pm on the hottest days of July.
• When you have no 0–4 °C, do not store: cook and eat the same day, process it (cheese, soured milk, dried food) or keep it alive (poultry, rabbits).
• When in doubt, throw it out. Smell and taste do not reveal the bacteria that poison.

What's inside

Chapters

1. Why food spoils in the warm
2. Five sources of cold without electricity
3. How cold each food needs to be
4. What needs a real fridge
5. Measuring: thermometer and hygrometer
6. Fast cooling without a fridge
7. Keeping the cold in: shade, insulation and night
8. Choosing a method for your homestead
9. Safety: food poisoning and equipment risks
10. Common mistakes
11. Printable checklist

Worksheets

• Weekly needs calculator
• Summer map of cold spots
• Where each food goes
• A year of cooling
• Temperature log
• Equipment and buying