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30 Carbohydrates & Calories
Transcript of 30 Carbohydrates & Calories
"Carbs" have something to do with food and energy and dieting...
But are they good or bad?
Carbohydrates are a type of molecule that are made up of:
Many different molecules are carbohydrates — including all the sugar molecules.
Let's go with the nutritionists' definition since we are most interested in the carbohydrates in our food.
There are two main types:
carbohydrates — such as sugars like glucose, sucrose, lactose, maltose, fructose, and dextrose.
Carbohydrates contain stored energy.
carbohydrates release energy quickly because they are small and easy to metabolize.
carbohydrates — like starches — release energy slowly because they are large which makes them more difficult for the body to metabolize.
Carbohydrates are Stored Chemical energy...
Gasoline, fuel oil, propane gas, wax candles, and other
also release stored chemical energy in the form of heat and light when they burn.
The carbohydrates in food do the same thing. They release heat and light when they burn, and we can measure the amount of heat that they give off when they burn.
In Lab 30, we will be burning various types of food.
It involves open flame, so you need to exercise caution, restraint, and self-control.
All of the burning is to be done inside the fume hood.
You may not take matches or butane firestarters away from the burning station, nor may you take them out of the classroom.
What is a calorie?
A calorie is a unit of energy.
carbs — especially simple carbs — are fattening.
In evolutionary terms, our food technology has eclipsed our physiological development.
Physically, we are still troglodytes, but we are surrounded by high-energy food choices.
Sugar is addicting because our bodies are overjoyed to have found a food source that provides so much energy so quickly.
They are programmed to store this energy so that they can avoid future deprivation and famine.
Food designers work tirelessly to give us delightful combinations of taste, texture, and oral gratification.
What does 200 calories look like?
Calories can be measured by burning food under a test tube filled with water and measuring how much the temperature rises.
What are Carbs?
Carbohydrates are a type of molecule...
over the precise definition of a carbohydrate. They argue over the ratio of the elements in any particular molecule and they argue over how the molecule is used.
Carbohydrates in food...
carbohydrates — such as starches like glycogen, cellulose, and chitin.
Carbohydrates store energy...
Energy can be stored in many different forms, but food energy is stored as chemical energy.
It is the amount of heat that is needed to raise the temperature of 1 gm of water 1º Celsius.
For instance, if you burned a Twinkie and it raised the temperature of 1 gm of water by 1ºC, then that Twinkie released 1 calorie.
Our bodies cannot ignore the excess carbs in our diets, so it stores them... as fat.
Good news: if you ever HAD TO LIVE as a cavemen again, your body would be metabolically ready for the challenge.
You are physically equipped to go back to eating wooly mammoth, giant ground sloth, or whatever else took your fancy.
Our inner-caveman cannot resist.
We are programmed to store excess energy...
Doing the experiments...
The class will be divided into four groups that will test nuts, marshmallows, Fritos, and crackers.
What if you couldn't find wooly mammoth?
There are "Good" and "bad" carbs...
Not all carbs have the same nutritional value...
(This link is broken. Take the space out from ww w.)
The "Calorie" that you see on a food package is different from the calories that you will be measuring in class.
The food package "Calorie" is actually a
It is the amount of energy needed to raise the temperature of 1,000 gm of water 1ºC.
A cashew, for instance, might release 2,000
calories when it burns — or 2 kilocalories.