Upon completion of the experiment, the students will be able to:
1. Identify the factors that influence the fat absorption during deep fat frying.
2. Identify the factors that influence steaming cooking.
3. Discuss the significance of temperature of the fat in influencing fat absorption during deep fat frying.
4. Discuss the significance of water temperature during steaming cooking.
During the laboratory class, we conducted experiments regarding deep fat frying, fat absorption and steaming cooking. We fried doughnut, French fries and prawn fritter while steamed bun and chocolate cakes.
What is deep fat frying? Deep frying involves immersing food into hot oil at a ...view middle of the document...
My group is assigned to make doughnut through deep frying method. The purpose of this experiment is to identify the significance of temperature of the fat in influencing fat absorption during deep fat frying. Deep frying involves fully immersing food in hot oil. It is an extremely fast cooking method, and, despite the use of liquid oil, is best classified as a dry cooking method because it does not involve liquid water.
From the table, we can see that the percentage of oil absorption decrease as the temperature increases. At the same time, the greasiness is being determined by the oil stain left on the kitchen towel. Apparently, the doughnut cooked under lower temperature will release more oil than those cooked under high temperature. Besides, it also affects the sensory evaluation test. Doughnut fried at high temperature is found to be more aromatic, has darker colour and less greasy. This is because when the oil is hot enough and the food is not immersed in the oil for too long, the oil will not enter the food itself. When the doughnut is fried at low temperature, it can absorb huge amounts of fat and is usually consumed along with the food, causing the total fat content ingested to increase tremendously. Therefore, we can conclude that the longer the frying time, the higher the percentage of the oil absorption. We should deep fry the food in between 1900C to 2090C so that the food will be less greasy and more aromatic.
Most people prefer deep fry food because it is normally well prepared, is crispy at the outside but tender on the inside, is more flavourful and has an appealing aroma. It is also a faster, more efficient heat transfer medium than steaming or boiling in water. During deep fat frying, vegetable oils can undergo oxidation, cyclization, polymerization, degradation and so on. It is the combination of these chemical changes that cause the rancid aromas, greasy mouth feel and impaired nutritional value in fried foods. Therefore, maintaining the quality of frying fats is critical to acceptance of the food fried in them. Monounsaturated vegetable oils are generally highly praised in deep frying process.
Some health concerns exist regarding deep frying; some are misconceptions, some are contentious, and some are well-founded. In brief, properly deep frying yields food that is crisp, not greasy, and is little different from other frying such as pan-frying. Ultimately, ingredients are fundamental: deep-fried leek is still leek, while a deep-fried Mars bar is still a Mars bar. All in all, one should control the oil consumption as it will have adverse effect on human health in long run such as obesity, hypertension and stroke.
1. Was there any difference in the fat absorption that occurred at the four temperature used for frying? If so, what temperature resulted in the least absorption?
Yes. For the lowest temperature (163˚C) used for frying the fat absorption is the most while the highest...