Carbohydrate Lab Wookbook

8/17/2019 Carbohydrate Lab Wookbook

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CARBOHYDRATE – LAB

Bring one Food item to be tested for Carbs on Lab day to receivesome Extra Credit!!!!Best are fruits, vegetables, cereals, dairy,honey, juices, chips, candies…I. BACKGROUND ON CARBOHYDRATES

Carbohydrates are organic molecules that contain the elements ________________, _________________ and _____________________ exclusively. They belong to the general class calledpolyalcohols because they have multiple ________________ group next either one ________________ or

______________on Carbons 1 or 2. Carbohydrates comprise about 60% o our daily caloric inta!e and arethe ma"or source o metabolic energy. Carbohydrates are categori#ed as monosaccharides, disaccharides, orpolysaccharides.

Monosaccharides $re the simplest carbohydrates and serve as the building bloc!s or _____ and ___________ saccharides. ive three examples o monosaccharides& _____________________________________________________________________________$llmonosaccharides are reducing sugars, 'hich means they ________________________ other molecules'hile being __________________________ at the same time. (ven the !etose )ructose is considered a

reducing sugar even though you learned that a !etogroup cannot be urther oxidi#ed. This is ho'& )ructose inthe presence o an oxidi#ing agent relocates its _____________ group rom carbon *2 to carbon *1,essentially turning into glucose and then undergoes oxidation.

Disaccharides +n a disaccharide, _______ monosaccharides are lin!ed together via a _____________________bond. actose, also commonly !no'n as _________sugar, is ound in mil! and mil!products. actose is made o a ___________________ and _________________________. -eople 'holac! the en#yme ________________________ are !no'n to be lactose _________________. ucrose,common table sugar, is composed o ____________________________ and _________________________/nli!e the monosaccharides, not all disaccharides are reducing sugars. The only disaccharidethat is no! red"cin# is ___________________

$o%&saccharides -olysaccharides are polymers composed o ___________________ monosaccharideunits. The most common polysaccharides have glucose as a building bloc!, and are dierent only in their

________________________.. tarch composed o the polysaccharides ____________________ and _________________________, is the ma"or orm o glucose storage in plants. $mylose 20% o starch isa linear chain o glucose 'hile amylopectin 30% is a branched polymer o glucose. lycogen is the ma"ororm o glucose storage in animals, and is ound in the liver and muscle. lycogen, li!e amylopectin in plants,is a branched polymer o glucose. +n mammals the brea!do'n hydrolysis o glycogen helps maintain

_________________________glucose levels bet'een meals. Cellulose is an unbranched chain o glucoseand is the ma"or ____________________________________ o plants. +n Cellulose the glucose moleculesare connected via a _________________________ glycosidic bond. 4umans do not possess cellulose andthereore cannot digest and utili#e the calories stored in cellulose. uch undigestable carbohydrates providethe ma"or source o ___________________ in our diet.

Common Tests for characterizing sugars

Benedic!'s !es! (or red"cin# s"#ars )"a%i!a!i*e 5enedicts reagent Cu27 reacts'ith reducing sugars to orm a red precipitate Cu7. )"an!i!a!i*e 5enedicts producesa sliding color scale ranging rom green to gold to red depending on the amountconcentration o the reducing sugar present in the sample.

8ra' in the redox brac!ets and label themabel all compounds9educed copper has the color& ______ :xidi#ed copper has the color& ______

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Se%i+ano(('s !es! (or ,e!oses& eli'anos test can be used to distinguish 6 carbonmonosaccharides hexoses that have a !etone group rom those hexoses that containan aldehyde group. ;ith !etoses the reagent produces a deep red color rapidly, 'hile'ith aldoses a light pin! color develops over a longer period o time.

Iodine !es! (or -o%&saccharides& +odine interacts 'ith the structure o amylose toproduce a deep blue


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. 5ased on your !no'ledge about the dierent tests or Carbohydrates, predict theoutcome inal color o the Benedic!s !es! and the Se%i+ano(('s test orucrose, and lucose

3. ;rite the (or4"%a not to be mista!en 'ith structureD or glucose, ructose,sucrose, maltose and lactose. ;hat did you ind out>

III. $ROCEDURES!ar! &o"r ho! +a!er 1a!h555Ma!eria%s :ne large bea!er 2B0


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C. IODINE TEST 0OR $OLYSACCHARIDES

• -lace B


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S!arch

Un,no+n

D. HYDROLYSIS O0 DISACCHARIDES AND $OLYSACCHARIDES+ndicate the color change in the table belo'. (xample& blue H orange

ucrose 7 42: ucrose 7 4Cl tarch 7 42: tarch 7 42:

+odine

5enedicts

E. TESTING 0OODS 0OR CARBOHYDRATES

Which two food items are you planning to test? ___________________________

Based on your knowledge about carbohydrates hypothesize what your food items

will most likely test positive for?

________________________________________________

8o the Tests& +ndicate the color change in the table belo'. (xample& blue H orange

Test Food 1: ________________ Food 2: ______________

Benedict’s

Seligwanoff’s

Iodine

7. CONCLUSION8 DISCUSSION

$ar!s A2 B2 C. – IDENTI0YING CARBS

/se the results table rom $, 5, C and identiy i the ollo'ing carbs 'here positive 'rite abig 7 into the respective boxor 9educing ugar, Ietose, tarch i negative leave emptyCar1 A. Red"cin#

car1B. Ke!ose C. S!arch

G%"cose

0r"c!ose

Lac!ose

S"crose

S!arch

Un,no+n

$ar! D. HYDROLYSIS/se the results table rom $, 5, C and identiy i the ollo'ing carbs 'here positive 'rite abig 7 into the respective boxor 9educing ugar, Ietose, tarch i negative leave empty

ucrose 7 42: ucrose 7 4Cl tarch 7 42: tarch 7 42:

-ositive or

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tarch

-ositive or9educing sugar $ar! E. 0OOD TESTING

/se the results table rom $, 5, C and identiy i the ollo'ing carbs 'here positive 'rite abig 7 into the respective boxor 9educing ugar, Ietose, tarch i negative leave empty

Test Food 1: ________________ Food 2: ______________

Reducing sugar

Ketose

Starch

How did your hypothesis hold up?

What was surprising/difficult about the food item testing

What did you like most about that lab?

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Carbohydrate Lab Wookbook