You need energy to heat the food, say, from 20 degrees to 100 degrees (the boiling point of water, under normal pressure). In some cases you can assume the food is mainly water, so use the heat capacity of water for your calculations.
Once the water has reached the temperature of 100 degrees, in theory no further energy is required to keep it at 100 degrees; if you manage to reduce heat losses to zero. For example, if you wrap the food in a blanket, it may keep hot for quite a while.
It could be either; but when you are talking about food, what is of interest is usually the energy content - meaning, chemical energy stored in the food. Heat IS energy, and a kilocalorie is the energy required to heat one kilogram of water by one degree Celsius.
Students can investigate the energy content in food by conducting experiments such as burning the food item and measuring the heat released, using a calorimeter to measure the energy content, or researching the nutritional information provided on food labels. They can also compare the energy content of different types of food items using online databases or resources.
That means how much energy it has.
calories
It is essentially chemical energy, which is released when the food is digested in the stomach
The energy content of a piece of food is determined by its macronutrient composition, particularly the amount of carbohydrates, proteins, fats, and alcohol it contains. These macronutrients provide calories that can be converted into energy during metabolism. The energy content of food is typically measured in kilocalories or calories.
To calculate calories in food using principles of food chemistry, one can use the Atwater system. This system assigns specific calorie values to macronutrients like carbohydrates, proteins, and fats based on their energy content. By analyzing the composition of a food item in terms of these macronutrients, one can calculate the total calories present.
A calorimeter. Basically you burn food inside a box and then measure the energy you get out of it. You have to make sure that the energy does not get out of the box
It depends on the food.
The energy content in food can be worked out using a method called calorimetry, where the food is burned and the heat produced is measured. This heat value can then be used to calculate the energy content in the food. The unit used for measuring energy in food is typically in kilocalories (kcal) or kilojoules (kJ).
Any unit of energy can be used to describe the energy content of food.
No, it list the energy content in calories, which is the amount of energy to raise a quantity of water by a certain temperature.