Health and Nutrition Chapter 4 Carbohydrates

What are disaccharides and name the three most common disaccharides in foods

Carbohydrates consisting of two sugar molecules. Sucrose is the most common disaccharide in foods.

Simple Carbohydrates

Category of Carbohydrates comprised of Monosaccharides and Disaccharides

What is the most abundant Monosaccharide in the body? Most Abundant in fruits and vegetables?

Glucose is the most abundant monsaccharide in blood and is consequentially the most abundant sugar in the body. Fructose is the most abundant in fruits and vegetables.

Psyllium

Insoluble nonpolysaccharide dietary fiber; consists of numerous alcohol units and found within the woody potion of plants. May decrease lipid absorption.

Hexose

Monosaccharide made of six carbon atoms

Lactose

Most abundant disaccharide found in milk and only one to have Beta Glycosidic Linkage. **During lactation, enzymes in mammary glands combine Glucose and Galactose

Nutritive Sweeteners

Naturally occurring, digestible carbohydrates (sucrose) Non Sugar Alternatives: Saccharin Aspartame Acesulfame K Sugar Alcohols Stevia (herbal additive) has been approved by the FDA recently.

Glycogen

Polysaccharide consisting of highly branched arrangement of glucose molecules found primarily in Liver and Skeletal Muscle. Used when glucose availability is low: fasting, strenuous or prolonged exercise. Analogous to Amylopectin

Amylopectin

Type of starch consisting of highly branched arrangement. Alpha-1,4 (linear) Branches at Alpha-1,6

Amylose

type of starch consisting of a linear (unbranched) chain of glucose molecules. Alpha-1,4

Stevia

"Natural Sugar Substitue" because it is derived from sunflower seeds. It is calorie free and considerably sweeter than processed sucrose (table sugar). Only Sweet PureVia Reb-A Rebiana SweetLeaf Truvia

Glucose

six-carbon monosaccharide and produced by photosynthesis in plants. Is used to generate ATP within body and is the preferred conduit of doing so for the nervous system and is the sole source of energy for RBC's. Can be converted into amino acids and fat for long-term storage. Body can store small amounts as glucose.

Why is Fiber an important part of a healthy diet?

Because Soluble fibers retain water and could reduce blood cholesterol. Insoluble fibers add bulk and could aid in weight management.

Monosaccharide

Carbohydrate consisting of a single sugar being comprised of the ratio CHO (1:2:1) Many natural monosaccharides but most common are Glucose Fructose Galactose *All of three are hexoses and all three exist as ring structures

Disaccharide

Carbohydrate consisting of two sugar molecules bonded together by a dehydration reaction (glycosidic linkage)

What diseases can adequate fiber prevent?

Cardiovascular disease, type 2 diabetes, obesity. Certain types of cancers if diet is low fat. Consumption of soluble viscous fibers can reduce blood cholesterol in some.

Diverticular Disease/Diverticulosis

Caused by the production of dry, hard feces due to the lack of sufficient fiber. Condition in the large intestine characterized by the presence of pouches that form along the intestinal wall. Diverticulitis is the inflammation of the diverticula (pouches) in the lining of the large intestine.

Whole-grain foods

Cereal grains that contain bran, endosperm, and germ in the same relative proportion as they exist naturally.

Soluble Fiber

Dietary Fiber that dissolved in water. Gel-forming soluble fibers are readily broken down (fermentable) by bacteria in the colon.

Insoluble Fiber

Dietary fiber that does not dissolve in water. Non-fermentable.

Maltose

Disaccharide consisting of two glucose molecules bonded together. Formed during the chemcial breakdown of starch. **Not found in very many foods but cereal starches are broken down into Maltose which is then fermented by bacteria to produce the alochol found in beer.

Complex Carbohydrates

Oligosaccharides (3-10) Raffinose Stachyose Polysaccharides (more than 10) Glycogen Starch Dietary Fibers

What are complex carbohydrates

Oligosaccharides (3-10) Raffinose Stachyrose Polysaccharides (more than 10) Glycogen Starch

Carbohydrate

Organic compound made up of varying numbers of monosaccharides

Fiber

Polysaccharide found in plants that is not digested or absorbed in the human small intestine.

Photosynthesis

Process whereby plans use light energy from the sun is transferred to chemical bonds within glucose from carbon dioxide and water.

Galactose

Six carbon monosaccharide found mainly bonded to glucose to form the milk sugar Lactose

Pectin

Soluble fiber (found in skin of fruits). Used to make jams and jellies. Might lower cholesterol by increased release of bile acids and cholesterol; significantly reduces the glycemic response.

Carbohydrate Loading

Technique used to increase body's glycogen stores

Sucralose

(Splenda) Low-calorie sweetener. Its production begins with sucrose which is then considerably processed. You get a sugar molecule with chlorine atoms. It is 600x sweeter than sucrose but yields minimal calories due to it being difficult to break down by the body. It is water soluble and stable so it is used over a wide range of beverages.

Sucrose

(table sugar) Disaccharide consisting of Glucose and Fructose. Often found in fruits and vegetables. Found in many foods and especially in sugar cane and sugar beets which can be squeezed to produce a liquid known as molasses. If you crystallzie that you get refined table sugar.

Cellulose

**Cellulose is the most abundant insoluble dietary fiber. B-glycosidic. Increases stool weight; may reduce transit time.

Why are sugars added to foods?

Sweeteners, and can be used to thicken and alter the texture of the foods.

When is nutritional value of Whole-Grains the most?

When Bran, Germ and Endosperm are all present. Bran has most of the fiber Germ supplies vitamins and minerals Endosperm is mostly starch. **Because milling removes bran and endosperm anything with refined flour lack fiber BUT most of the nutritional value is restored once the products undergo fortification.

Where is dietary fiber found?

Whole grains, legumes, fruit, vegetables. Varying dietary fibers are classified based physical properties (solubility in water) Soluble vs Insoluble

Sources and use of Insoluble Dietary Fibers

Whole-grain flour, wheat bran, seeds, vegetables. Because they don't form viscous gels and are not broken down by bacteria in GI, they just pass through and increase mass and volume of stool which would alleviate constipation by stimulating the peristalisis in colon.

High-Fructose Corn Syrup

Widely used sweetener in soft-drinks, fruit juice, beverages. A substance derived from corn that is used to sweeten foods and beverages. Equal amounts of fructose and glucose. **used extensively by food managers and now accounts for 7% of total energy intake in US>

How is HFCS prepared?

You treat corn with enzymes and find glucose-rich syrup. During this process, some glucose is converted fructose. The ratio for sucrose is half and half for Gluc and Fruc but now the ratio is 55% Fructose and 45% Glucose. **NSDA says it mixes better with liquids and it is more cost-effective to produce HFCS than it is to produce Sucrose-based products.

According to USDA, how many pounds of HDCS are consumed by Americans per annum?

35 pounds More HFCS sweetened foods are consumed than are table sugar sweetened. **It is speculated that HFCS in excess consumption may be fueling the American Obesity Epidemic

Sugar Alcohols

Alternative Sweeteners Neither sugar nor alcohol but rather POLYOL's which means it is a sugar molecule with multiple alochol groups attached to it. Occur naturally in plants, fruits, and have half the sweetness and calories of sucrose (1-2 kcal/g) Xyolitol, Sorbitol, Mannitol found in chewing gum, candies, mints, toothpastes, mouthwashes and cough syrups. **Advantage is that they do not readily promote tooth decay as does Sucrose. In excess however they can serve as a laxative and induce diarrhea.

What are food sources of fiber?

Dried Beans, Peanuts. Oats, barley, legumes, rice, bran, psyllium, seeds, soy, and fruits (water soluble viscous dietary fibers). **Based on USDA: Excellent Source must have 20% Daily Value of fiber or 5 grams of fiber per serving. Good Source must have 2.5-4.9 grams of fiber per serving.

Functional Fiber

Fiber that is added to food to provide beneficial physiological effects. Derived from natural fibrous plants.

Dietary Fiber

Fiber that naturally occurs in plants. We cannot digest these polysaccharides (cannot break the glycosidic linkages).

Downside to added sugars compared to natural?

Foods with natural sugars are generally nutrient dense relative to the calories within whereas the added sugars do not impart that quality.

Oligosaccharides

Found in dried beans, soy beans, peas, lentils. 3-10 units Humans lack digestive enzymes to process these so they go through the digestive tract untouched to the Large Intestine where bacteria break them down and you get gas or flatulence. They are part of cell membrane, play role in cell-cell recognition. Made in breasts and infused with milk as they are part of complex system that helps protect infants from disease-causing pathogens (reason why mothers are encouraged to breast feed).

Describe the rings of Glucose, Galactose, and Fructose

Glucose and Galactose are six member rings and the hydroxyl on the 4th carbon for Glucose is below and above for Galactose. Fructose forms a five member ring. Fructose is a monosaccharide that is found in honey, fruits, and vegetables.

Gums

Highly soluble and viscous nonstarch polysaccharides used to thicken foods. Reduce blood cholesterol and sugar.

Hemicellulose

Insoluble and has variety of monosaccharides.

What happens when glucose availability is low but there is a need?

Liver glycogen breaks down into glucose and is released into the blood. Muscles lack the enzyme needed to release glucose into the blood so the glucose from there is used to fuel physical activity. Some athletes try to increase their capacity via Carbohydrate Loading

What are the health benefits of fiber?

NOT REQUIRED DAILY COMPONENT but because dietary fibers cannot be digested in the small intestine they pass to the large where they are broken down by bacteria/microorganismwhich produce flatulence as a byproduct but also lipids and other materials that nourish the cells in the colon. The fiber introduction promotes the proliferation of helpful and favored microorganisms within the large intestines which inhibits the development of disease-causing bacteria in the large intestine. Studies show it protects against cardiovascular disease, obesity, type 2 diabetes; needed for digestive health. Sponge-like effects of soluble viscous dietary fibers can soften fecal matter. Also fiber might bind to cholesterol in GI tract which would prevent absorption of cholesterol; it might also delay the gastric emptying which would help promote satiety (which in turn could reduce blood glucose levels). Soluble fermentable fibers can also serve as prebiotics which would help "friendly" bacteria grow in colon.

Today the average American consumes 89 grams of added sugars (335 kcal) per day.

Nearly half (46%) of the added sugars in the American diet are from soft-drinks. Research suggests that consumption of soft-drinks (sweetened) is correlated with increased body weight.

Saccharin

Non Sugar Artificial Sweetener. Extremely sweet, very stable, and inexpensive to produce. Sweet'N Low Sugar Twin

Aspartame

Non Sugar Sweetener Consists of two amino acids bonded together and has same energy content as sucrose; but is 200 times as sweet. Anyone with PKU cannot metabolize the sweetener which may cause adverse effects. NutraSweet Equal

Acesulfame K

Non Sugar sweetener. Is a salt that contains K and is known as Sweet One. Heat stable and can be used in many products such as frozen desserts, yogurt, gum, syrups, alcoholic beverages.

B-Glucan

Non starch polysaccharide composed of branches chains. Increases stool weight due to viscosity and bacterial fermentation. May reduce blood glucose levels.

Total Fiber

The combination of dietary fiber and functional fiber.