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Chemistry of chocolate. Barbora Ürgeová Petra Vrchovecká. History of chocolate. 900 B. C.: Maya – chocolate drink 16th century: chocolate brought to Europe by Spanish explorers 1657: first chocolate shop in London 18th century: chocolate manufactured in USA
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Chemistry of chocolate Barbora Ürgeová Petra Vrchovecká
History of chocolate • 900 B. C.: Maya – chocolate drink • 16th century: chocolate brought to Europe by Spanish explorers • 1657: first chocolate shop in London • 18th century: chocolate manufactured in USA • 19th century: Peter of Vevey (Switzerland) perfected process of making milk chocolate
Process of making • HARVESTING: The cacao pods from the cacao tree are crushed and left to ferment → drying cacao beans from the pods → beans are roasted, graded and ground → cocoa butter is removed from chocolate liquor. • BLENDING: Chocolate liquor is blended with the butter → →different types of chocolate. • CONCHING: blended chocolate mass is kept liquid by frictional heat → the chocolate mass is stored and heated in tanks. • TEMPERING: the mass is cooled in stages → the mass is rewarmed followed by cooling down.
Kinds of chocolate • UNSWEETEDCHOCOLATE=ground roasted chocolate beans with no other added ingredients • SEMI-SWEET CHOCOLATE = a dark chocolate with lower sugar content • WHITE CHOCOLATE = a confection based on cocoa butter without the cocoa solids
Component Plain choc. Milk choc. White choc. Nutrients protein 3,2 g 7,6 g 7,5 g lipids 33,5 g 32,3 g 37 g carbo-hydrates 60,3 g 57 g 52 g pure lecithin 0,3 g 0,3 g 0,3 g theobromine 0,6 g 0,2 g -- Mineral substances calcium 20 mg 220 mg 250 mg magnesium 80 mg 50 mg 30 mg phosphorus 130 mg 210 mg 200 mg Trace elements iron 2 mg 0,8 mg traces copper 0,7 mg 0,4 mg traces Chocolate composition In 100 g of chocolate
Vitamins A 40 IU 300 IU 220 IU B1 0,06 mg 0,1 mg 0,1 mg B2 0,06 mg 0,3 mg 0,4 mg C 1,14 mg 3 mg 3 mg D 50 IU 70 IU 15 IU E 2,4 mg 1,2 mg traces Vitamins in chocolate
Theobromine • Alkaloid found in cocoa beans and chocolate • Used in medicine as diuretic, vasodilator, and myocardial stimulant. • Chemically related to caffeine (methylxanthine family) • Mild, lasting stimulant with a mood improving effect
Caffeine • Very small amounts in chocolate • Different properties and effects as theobromine • Strong effect on CNS • Increases alertness
Psychological effects of chocolate • Lethal toxicity for animals - theobromine in chocolate is toxic -animals are unable to metabolize the chemical effectively → epileptic seizures, hearts attacks, internal bleeding • Health benefits for humans - flavonids and gallic acid help protect blood vessels, cardiac health and prevent cancer - it also has been demonstrated to counteract mild hypertension
Thank you for your attention Sources: • www.answers.com/chocolate • www.erowid.org/chemicals/ chocolate/chocolate_chemistry • www.chocolat.ch/chocsuisscomp.htm • chemistry.about.com/library/weekly/aa090301a.htm
Dictionary • harvest – sklizeň, žně • cacao pod – kakaový lusk • blend – míchat • trace elements – stopové prvky • alertness – bdělost • seizure – záchvat • cancer – rakovina