How to Calculate Roasting Times
- 1). Determine four time calculations: preheating; initial hot roast; low temperature roasting; and final hot roast.
- 2). Write down 20 minutes for preheating the oven and 30 minutes for the initial hot roast. Roasting needs to start in a hot oven, 400 to 450 degrees F for 30 minutes before you lower the temperature.
- 3). Calculate the time for the longer low temperature portion of the roast. Multiply the total weight of the food in pounds by 30 minutes when roasting below 300 degrees F, 20 minutes when roasting from 300 to 375 degrees F, and 15 minutes when roasting at 400 degrees F and above. For example, 10 pounds of food in a 350 degree oven would slow roast for about 3 hours and 20 minutes.
- 4). Add another 20 minutes for a final hot roast period. The oven again will be turned up to 400 to 450 degrees during this final part of the cooking process.
- 5). Add the four times to calculate total roasting time. This time will give you a good estimate and allow you to monitor the progress of the roast.
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