FScN 3102 Introduction to Food Science
To compare different heating methods for rate of cooking and for impact on final product quality. This will be accomplished by cooking potatoes and carrots for varied times with varied heating procedures.
Work in groups of 4. The TAs will tell you who else is in your group. Each of the following products/treatments should only be made once in each group of four. You will be responsible for knowing what the others in your group have done and for making observations of their products. The others in your group will need to see and evaluate the products you prepare.
Use uniform size whole potatoes - wash them thoroughly and weigh each one prior to heating:
After heating, weigh, cut in half, and expose to air. Evaluate the flavor, texture and appearance. Calculate the percent weight loss. Record the times, weights, and observations for all treatments.
- Bake (need 3 potatoes): puncture skin before baking at 400°F. Remove every 15 min up to 45 min.
- Microwave (need 5 potatoes): puncture skin before heating - bake individually on a paper towel for 1, 2, 3, 4 and 5 minutes.
Compare the different cooking times within each method. Explain the differences. Then, compare the 3 minute microwave, the 45 minute baked and the 15 minute pressure cooked samples. Explain the differences in sensory qualities among methods.
Wash and trim away damaged portions. Pare and slice into 0.5 cm pieces. Do all the treatments below. Use about 60 g for each treatment.
- Loosely covered saucepan: Use 1 1/2 cup of water in a saucepan with the cover in a tilted position to allow steam to escape. Add carrots after water boils. Do not let it boil dry. Cook for 10 minutes and 15 minutes.
- Steamer: cook for 10 minutes and 20 minutes. (1 cup of water in the bottom of the steamer).
- Pressure saucepan: cook for 1/2 minute and 1 1/2 minutes. Use 1/2 cup of water and start timing when 15 LB pressure is reached. See instructions for using the pressure saucepan under potatoes.
- Microwave: put in a glass custard cup with 2 tsp. of water. Heat for 1, 3, and 5 minutes. Evaluate for doneness using texture as a measure.
Describe differences between the different times within each cooking method.
Describe differences between the methods selecting the 3 minute microwave, the 1/2 minute pressure saucepan, the 10 minute steamed and the 10 minute boiled.
Lab notebook: From this lab you should have the following information in your lab notebook:
||Weights before and after cooking for each vegetable and each treatment (share values with your lab group members )
||Notes on the texture and appearance of the cooked vegetables.
||A paragraph or two about the differences you observed due to cooking times and cooking methods and why those differences existed. Use your text and lecture notes for help.
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Last Modified - 8/7/96