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Unformatted text preview: Lecture 23
Water Liquid common to almost all foods Found in solid foods as well as all liquids – Fresh bread is 60% water Human body is ~3/4 water Most important nutrient Bottled Water
Bottled Water Second most popular beverage in U.S.
Regulated by FDA
Mineral water – Water as it comes from its source
– All naturally obtained water contains minerals Calcium, magnesium, iron, sulfur Deionized water – All mineral content removed via ion exchange Distilled water – Mineral content removed through distillation (converted to steam and condensed by cooling) Sparkling Water
Sparkling Water Sparkling water—contains CO2 Naturally occurring Commercial – seltzer Club soda—filtered and carbonated + added salts – Bicarbonate—origin of the term “soda”
– Sodium citrate
– Sodium phosphate Tap Water
Tap Water Regulated by EPA Municipal water supplies vary – Wells
– Rivers, canals, other fresh water supplies Chlorinated May be flouridated – Important dietary source to prevent dental caries
– Flouridation level not to exceed 1 ppm Mottled Enamel
Mottled Enamel Sport or Isotonic Beverages
Sport or Isotonic Beverages Developed for use in physical performance to prevent dehydration and replace electrolytes, with added calories Useful if physical activity is greater than 1 hour. CHO sources
– Sucrose, glucose, maltodextrin
– Electrolytes—Na and K Red Bull
Red Bull Expensive energy drink Contains—glucose, sucrose, B complex vitamins, caffeine, taurine, and glucuronolactone Controversial with a loyal following Carbonated Beverages
Carbonated Beverages Most popular beverage in U.S. More commonly referred to as “soda” on the East Coast and “pop” in the midwest.
– In midwest “soda” refers to sparkling water “pop” refers to the sound of opening a can 90% water and 10% sugar with flavor, color, acid, and preservative. Manufactured from flavored syrup and carbonated water. Soft Drink Nutrition
Soft Drink Nutrition Is there any? Explosion of average serving size Citric, phosphoric, and malic acids may erode tooth enamel Sugars are a substrate for cariogenic bacteria Coffee
Coffee Originated in the Middle East Brought to Europe by Venetian traders to become the drink Highly merchandizable item, growth in coffee bar industry has been substantial over the past 10 years Coffee Beans
Coffee Beans Fruit of the coffee tree (seed or bean)
Harvested red—called green coffee
Trees require a moist, warm climate. Harvested beans are shipped, roasted, and blended in the country where it will be consumed.
US blends are
– blended to achieve desirable body and aroma, with limited astringency and bitterness
– Roasted according to consumer preference
– Preferred light roast Coffee Composition
Coffee Composition Small amount of CHO Responsible for carmelization in roasting Small amount of protein Reasonably high fat Flavor
Rancidity through oxidation. Begins as soon as beans are ground.
Change more pronounced in finely ground coffees
After opening—store refrigerated
Some is lost through roasting
Decaffeinated coffee is produced by treating beans with solvents or a hydrating wash. Decaffeinated coffee ~97% caffeinefree Caffeine Caffeol—responsible for flavor and aroma Organic acids—responsible for sourness and slight bitterness Tannin Responsible for bitterness Common Coffee Brewing Common Coffee Brewing Equipment Drip method – Glass or metal carafe
– Brews small amount, usually 1012 c at a time
– Hot water comes in contact with coffee grounds once to extract caffeol and caffeine Perculator method (urn) – Brews a large quantity, usually 23 gallons at a time
– Hot water boils to circulate over grounds multiple times, extracting caffeol, caffeine, and tannins Coffee Urns
Coffee Urns Drip Coffee Pots
Drip Coffee Pots Keurig
Keurig Tea Plantation
Tea Plantation Tea Leaves
Tea Leaves Tea
Tea Grows in tropical and semitropical climate Leaf of an evergreen shrub, camellia sinensis Leaves are picked by hand Composition of Tea
Composition of Tea Tannins – Color, bitterness Theine – CNS stimulant Epigallocatechin gallate (EGCG) – Catechin with antioxidant properties, found in both green and black tea Polyphenol – Generic term which refers to flavonoids, catechins, theaflavins, thearubigens in green and black tea. Theaflavin in black tea—responsible for flavor and color Thearubigen in black tea—color and flavor Black Tea
Black Tea 78% of world’s production Popular in US, Great Britain, Europe, and India Produced by spreading leaves out to air dry and promote a natural fermentation to provide the deep brown color
– Withered, rolled, dried, and fired (heated)
– Pekoe and orange pekoe—grade and leaf size, not flavor Black Tea
Black Tea Green Tea
Green Tea 20% of the world production Preferred in China and Japan Leaves are steamed (retains green color) to inactivate enzymes, then rolled and fired (not fermented) Contains larger amount of epigallocatechin gallate (EGCG)
– Flavonoid antioxidant, commonly called catechin, believed to reduce cancer risk Green Tea
Green Tea Oolong Tea
Oolong Tea Partially fermented Short fermentation period does not allow color change in leaf so it is only partially blackened Flavor and aroma is in between black and green teas Oolong Tea
Oolong Tea Black vs. Green Tea
Black vs. Green Tea – Color is inversely proportional to flavor Green is much more flavorful than black Brewing Tea
Brewing Tea Bring fresh, cold water to a full rolling boil and let cool slightly Pour hot water over teabag Steep for 35 minutes for black or oolong tea Steep 11 ½ minutes for green tea Cocoa and Chocolate
Cocoa and Chocolate Tree Theobroma cacao grows in the tropics Leathery berries, seeds in pods, each pod containing ~ 3040 seeds Cocoa and chocolate are produced by grinding the seeds After harvest, seeds are fermented for 57 days to develop flavor Further Cocoa Processing
Further Cocoa Processing Seeds are cracked to separate shell from bean Cracked seeds are called chocolate nibs Nibs are ground and heatedchocolate liquor Chocolate Nibs
Chocolate Nibs Chocolate Liquor
Chocolate Liquor Composition of Chocolate
Composition of Chocolate Fat – 5058% cocoa butter
– In chocolate, will migrate to surface to cause “bloom” Starch – 11% Flavor
Theobromine – CNS stimulant Health Benefits of Chocolate
Health Benefits of Chocolate Flavonoid content – Flavonolnitric oxide – blood pressure control
– promote healthy blood flow by preventing clotting
– High ORAC—oxygen radical absorption capacity Dark chocolate 13000 ORAC Milk chocolate 6700 ORAC Chocolate Bloom
Chocolate Bloom Alcoholic Beverages
Alcoholic Beverages Beer Wine Distilled spirits – Serving sizes vary, but all contain same amount of alcohol, 1 oz. Beer—12 oz. Wine—5 oz. Distilled spirits—1 ½ oz. Beer
Beer Yeast fermentation of grain (barley) Malt is produced through conversion of starch from grain maltose, glucose – Grain is soaked in water, called steeping, causing the grain to sprout or germinate.
– Germinated grains are dried (kilning) malt
– Barley malt is mashed (moist heat to gelatinize starch) to convert nonfermentable starches to simple sugars to produce wort
– Liquid wort is high in sugars and easily fermented by yeast Brewing of Beer
Brewing of Beer
6. Hops are added to wort and boiled.
Cooled mixture inoculated with Saccharomyces carlsbergensis yeast.
Ferments for 9 days
Temperature lowered to 32o F to stop the production of alcohol from yeast.
Mixture is filtered to remove impurities.
Lagering—storing beer in tanks for several weeks to months to develop flavor Wine
Wine Fermented fruit juice, usually grape Three step process – Fermentation—pH 3 (acid) reduces growth of most microorganisms, but yeast
– Racking—wines are allowed to settle, allowing heavier particles to sink to the bottom of container. – Aging—drawn out wine is stored in casks for months to years to continue fermentation and develop flavor Distilled Spirits
Distilled Spirits Hard liquor produced by distillation process (steam product is quickly cooled) Produced from grain or fruit Amount of alcohol = proof
– 20 proof = 10% alcohol ...
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This note was uploaded on 11/20/2011 for the course FOOD SCI 709:201 taught by Professor Tangel during the Spring '11 term at Rutgers.
- Spring '11