N 207 - carbohydrates

• glucose: 6 membered ring and 6 carbon atoms (OH is down on C4)
• galactose: 6 membered ring and 6 carbon atoms (OH is up on C4)
• fructose : 5 membered ring and 6 carbon atoms

• sucrose = fructose + galactose (in table sugar)
• maltose = glucose + glucose (in beer)
• lactose = glucose + galactose (milk/least sweet)

the bond that holds 2 glucose units together

• hydrolysis is a reaction that slips the molecule in 2
• added H2O

• starch : amylopectin and amylose
• glycogen
• celllulose

• storage form of energy in the body
• made of glucose units
• stored in the liver
• short term glucose
• liver cells produce glucose from glycogen to be sent directly to blood
• muscle cells can also produce glucose from glycogen but must use it for themselves

• storage form of energy in plants
• long chains of glucose 
• amylose = unbranched
• amylopectin = branched
• influences cooking characteristics

provides in them, roots, leaves and skin of plants

• the salivary glands secrete saliva into the mouth to moisten the food
• the salivary enzyme amylase begins digestion and hydrolyses the starch
• Starch → small polysaccharides and maltose

the stomach acids intactivate salivary enzymes, halting starch digestion

• the pancreas produces amylase that is released through the pancreatic duct into the small intestine
• Starch → small polysaccharides and maltose

• then discharges enzymes on the surface of the small intestinal cells hydrolyze the disaccharides into monosaccharides
•           
• Maltose (by maltase) → glucose + glucose

• Sucrose (by sucrase) → glucose + fructose
• Lactose (by lactase) → glucose + galactose

intestinal cells absorb these monosaccharides

it mechanically crushes and breaks down the finer and mixes it with saliva to moisten it fr swallowing

fiber is not digested and it delays gastric emptying

• fiber is not digested
• it delays absorption of other nutrients

• fiber passes intact through the digestive tract to the large intestine
• heres how the bacterial enzymes digest finer
• Some fiber (by bacterial enzymes) → short chain fatty acids + gas
• fiber holds water and regulates bowel activity
• fiber binds to water and binds to substances like bile, cholesterol and some minerals and carries them out of the body

• 1. the monosaccharides enter the capillaries of the intestinal villi of the small intestine
• 2. they travel to the liver via the portal vein
• 3. in the liver, galactose and fructose are converted to glucose

• lactose is not properly digested due to the lack of production of lactase on the brush border due to ageing or disease
• NOT an allergy
• undigested lactose can cause some symptoms like nausea, diarrhea, cramps, bloating, flatulence
• it creates an osmotic effect : holds water in the lumen
• solutions: milk with a mean, yogurt, cheese, lactose reduce milk, lactase pills

• precursor for aa
• converted to glycogen for energy storage (short term energy store)
• converted to fat for energy storage (long term energy store)
• oxidized for energy
• prevents ketosis (accumulation of ketone bodies in the blood)

• brain cells
• blood cells
• spermatogenesis
• mammary gland
• fetus

↓ blood sugar concentration

↑ blood sugar concentration

• 1. when a person eats, blood glucose ↑
• 2. ↑ blood glucose stimulates the pancreas to release insulin into the blood
• 3. insulin stimulates the uptake of glucose into cells and stage as glycogen in the liver and muscles
• insulin also stimulates the conversion of excess glucose into fat for storage

• 4. as the body uses glucose, blood levels decline ↓
• 5. ↓ blood glucose stimulates the pancreas to release glucagon into the blood stream
• 6. glucagon stimulates liver cells to break down glycogen and release glucose into the  blood
• 7. blood glucose begins to rise ↑

• 10% of cases
• high blood glucose
• destructions of pancreatic cells
• insulin secretion by the B cells of the pancreas is ineffective
• autoimmune, viral
• usually in children
• treatment = exogenous insulin injections, low fat, low GI CHOs and fibre, balance diet and exercise

• 90% cases
• high blood glucose
• cell are not sensitive to insulin
• "insulin resistance"
• treatment = low fat, low GI CHOs and fibre, weight loss, exercise, diet

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its a method to classify foods according to their potential for raising blood glucose

GI% = glycemic response to 50g of food x100% / glycemic response to 50g of glucose

• lowering the glycemic index of the diet may improve blood lipids and reduce CVD risk
• low glycemic diet can also help with weight management

• the decay of teeth
• begins when acid dissolves the enamel that covers the tooth
• if not repaired, the decay may penetrate the dentin and spread into the pulp of the tooth, accusing inflammation, abscess and possible loss of the tooth

• sugars from foods and breakdown of starches contribute to tooth decay
• bacteria ferment the sugars in the mouth and produce an acid that erodes tooth enamel causing dental carries

• sugar alcohols like xylitol, mannitol, sorbitol
• they're not fermentable and are slowly absorbed
• about 2kcal/g
• "sugar free" dow not mean "no cal"

• from cell walls
• structural
• less fermentable

sources = cellulose, ligin, hemicellulose

• actions in the body =
• ↑ fecal weight and speed fecal passage through colon,
• provide bulk and fullness

• health benefits = alleviate constipation, 
• ↓ risks of appendicitis,
• hemorrhoids,
• may help with weight management

foods = fibrous veg, wheat bran

• cement
• glue from plants
• more fermentable

sources = pectin, gums, mucilages

• Actions in the body = 
• ↓ blood cholesterol by finding to bile,
• slow glucose absorption,
• slow transit of food through upper GI tract, hold moisture in stools,
• softening them,
• yield small fat molecules after fermentation that the colon can use for energy

• Health benefits =
• ↓ list of heart disease
• ↓ risk of diabetes

• foods = additives - carrageenan, guar gum (emulsifier), pectin in jams
• beans, legumes, nuts, fruits, oats, barley

• its not digested by out enzymes
• slows abosrption for better glycemic control

• soluble fiber = binds bile acids 
• ↓ enterohepatic circulation
• ↓ fat, cholesterol and fat soluble vitamin absorption
• ↓ cholesterol levels

• insoluble fiber = binds cations
• phytates ↓ Fe, Ca, Zn absorption

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• ↑ GI motility, speeds up transit
• attracts water, bulk
• ↓ constipation, diverticular disease, haemorrhoids 

• fermented by intestinal bacteria
• gas - CH4, H2, CO2
• short chat FAs 
• energy for colonocytes
• binds bile acids and toxicants - protects colon

current intake = 20-25g/d

• AI for finer base don energy intake:
• 38g/day for men
• 25g/d for women

NO UL FOR FIBER

• 1. weight control
• foods tend to be ↓ in fat and ↑ satiety and bulk

• 2. heart disease
• ↓ in saturated fat, ↑ in phytochemical
• ↓ cholesterol

• 3. cancer
• ↓ colon cancer risk,  ↓ pH phytochemical, vitamins

• 4. diabetes
• glycemic control
• weight control

5. GI health