Roasting Time
Total cooking time from the meat's weight and a per-kilogram rate.
Formula
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Example
3 kg at 40 min/kg: t = 120 min
How it works
This formula calculates the total roasting time by multiplying the food's mass by a cooking rate given in minutes per kilogram. It works because the roast time is assumed to scale proportionally with weight: if the roast is twice as heavy, it usually needs about twice as long to cook at the same rate. The result is an estimate, so oven temperature, shape of the cut, and whether the meat is stuffed can still change the actual time.
When to use it
Use this when a recipe or cooking chart gives a fixed number of minutes per kilogram for a roast, chicken, or similar cut of meat. It is especially useful for planning cooking schedules and estimating when food will be ready.
Worked example, step by step
A 2.5 kg chicken is cooked at 50 min/kg. Use the formula: t = m × r Substitute the values: t = 2.5 × 50 Calculate: t = 125 Final answer: t = 125 minutes
Common mistakes to avoid
- Using grams instead of kilograms without converting first
- Adding the numbers instead of multiplying weight by minutes per kilogram
- Forgetting that the result is in minutes, not hours
Did You Know?
A meat thermometer beats any timing formula — doneness depends on internal temperature, not the clock.
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