Lecture 11: Lipids Flashcards
General uses of lipids
foods soaps candles paints lubricants biofuel
What is the most common form of lipid?
Triglycerides
What is the caloric value of Carbohydrates, proteins and fats?
Carbs: 4 kcal/gram
Proteins: 4 kcal/gram
Fats: 9 kcal/gram
Calorie
Amount of energy it takes to raise water 1 degree C
What does the USDA recommend for fat intake?
Eat less than 35% of total calories from fats and oils (keep it between 20-35% of total calories
Trigycerides
3 fatty acids attached to glycerol
Triglyceride hydrolysis
During digestion we need to hydrolyze the fatty acids off the glycerol
Lipids break down lipases
What is the importance of triglyceride hydrolysis?
Only free fatty acids are absorbed
Vegetable oil
Is triglyceride extracted from a plant
Been used for millennia
Edible oil is extracted primarily from seeds
What is the largest quantity of all vegetable oils
Palm oil
What is the largest in quantity of all edible vegetables oils
Soybean
Mechanical extraction of oil
“crushing” or “pressing”
Solvent extraction
the most common solvent is petroleum-derived hexane
This technique is used for most of the “newer” industrial oils such as soybean and corn oils
How is olive oil made?
After crushing of the fruit, water and oil can also be easily separated by centrifugation
What does virgin mean in virgin olive oil?
“That the oil has been extracted from the olives using purely mechanical means”