The short answer
Set it to 5C or below, keep a single "eat me first" shelf at eye level, and put new shopping behind old rather than in front of it.
- Check the temperature with a fridge thermometer. Many home fridges run too warm, which costs days of shelf life on everything inside.
- Designate one shelf at eye level as the eat-first shelf and put anything near its date there.
- Rotate. New shopping goes behind the old, exactly the way a shop does it.
- Know the door is the warmest part, so it is for condiments and not for milk.
- Keep it reasonably full but not packed. Air has to circulate.
What will ruin it
"Use by" is a safety date and should be respected. "Best before" is about quality and most dried, tinned and frozen goods are perfectly fine well past it. Confusing the two causes a lot of unnecessary waste.
Why it works
Bacterial growth roughly doubles for every few degrees above 5C. A fridge at 8C is not slightly worse than one at 4C, it is substantially worse, and it shows up as food that goes off before its date.
Tipking is general household information, not professional advice. Test anything on a hidden patch first. Full disclaimer.
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