catbohydrates: structure, function and analysis Flashcards
What is the general formula for carbohydrates?
CnH2nOn or Cn(H2O)n.
What are the two main types of monosaccharides based on the number of carbons?
Pentoses (C5H10O5) and Hexoses (C6H12O6).
What are the two types of ring structures in monosaccharides?
Pyranose (6-membered ring) and Furanose (5-membered ring).
Define a disaccharide and provide an example.
A carbohydrate with two sugar units connected by a glycosidic bond, e.g., sucrose.
What are polysaccharides?
Carbohydrates made of 10 or more sugar units, e.g., amylose and cellulose.
What is the difference between a homopolysaccharide and a heteropolysaccharide?
Homopolysaccharides contain one type of monosaccharide, while heteropolysaccharides contain two or more types.
What is the primary carbohydrate used for energy transport in plants?
Sucrose.
How does starch function in plants?
It acts as a long-term energy storage molecule.
Name two roles of dietary fiber in human nutrition.
Aids colonic motility and serves as a substrate for gut microbiota.
What is gelatinization in food production?
The process of breaking down starch granules using water, heat, and shear to improve texture.
Name two products where non-starch polysaccharides are used to modify texture.
Ketchup and jelly.
What is a common application of sugar alcohols like sorbitol in food?
They are used as sweeteners in sugar-free products.
Where does the enzymatic breakdown of starch begin in the body?
In the oral cavity with salivary amylase.
What happens to carbohydrates in the small bowel?
hey are broken down into monosaccharides and absorbed into the bloodstream.
Why is carbohydrate analysis important?
For food labeling, quality control, and studying nutritional impacts.
What are two methods for determining carbohydrate content?
Spectroscopy and enzymatic hydrolysis.
How does refractive index measurement help in carbohydrate analysis?
It measures the bending of light in a solution to infer sugar content.
What structural feature distinguishes amylose from cellulose?
Amylose has α(1–4) glycosidic linkages (helical structure), while cellulose has β(1–4) linkages (linear structure).
What role do carbohydrates play in food production?
They influence texture, sweetness, and stability of food products.
What are the two perspectives for analyzing total carbohydrates in food?
Quantitative (e.g., total sugar content) and descriptive (e.g., structure and composition).
What tool can be used to measure the density of a sugar solution?
A hydrometer or densitometer.
How can you separate carbohydrates from fats in food samples?
By using solvents like hexane.
What is the purpose of using a refractometer in a lab session?
To measure the concentration of dissolved sugars in solutions.
