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Science Academic Fair

Binder and Backboard

Requirements

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Science Binder ContentsThe following items must be in the binder and in this order:Title page

Research paperBibliographyAbstract this is done after the experimentResearch PlanPurpose

HypothesisaterialsProcedure!ataResults"onclusion#$%& forms'ournalPictures

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(nce you type e)erything for the binder*

you+ll print each page twice,

(ne copy for the binder

The second is modified a little for thebac-board

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&or those selected to go to the !iocesan

$cience &air:

The title page can not ha)e your name on it,

.ou will ha)e to reprint the title page,Therefore* please sa)e all typed pages in a

file and bac-up to flash dri)e,

.our name can go on the bac- co)er of your

binder,

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AbstractThepurposeof this project was to investigate the effect of different amounts of acid

on the curdling process of milk. This was accomplished by experimentation and

comparative studies. For my experiment, I used four different types of milk skim, !",

whole, and whipping cream. For each milk type, I heated the milk, poured the same

amount into five separate containers, added different amounts of lemon juice #acid$ to

each sample, allowed the milk to cool, poured the milk through a cheesecloth to separate

the curds from the whey, allowed the samples to dry overnight, and weighed the curds lefton the cheesecloth. %y hypothesisfor this project was that the higher the acid content of

the milk, the &uantity of curds produced would be higher. 'igher milk fat contents

should also increase the amount of curds produced. The constants and controls in my

experiment were the amount of milk used and the temperature the milk was heated to.

The variables in my experiment were the amounts of acid added to the milk, and the

different types of milk used. The resultsof the experiment showed that when more lemonjuice was added to the milk, more curds were produced. The experiment also showed that

higher milk fat contents produced more curds. The results show that my hypothesis was

correct. If I were going to do this experiment again in the future or expand this

experiment, I would put more lemon juice in the milk and keep Increasing it to try to

determine the maximum amount of curds that could be produced.

/riting the Abstract

&ollow handout pro)ided earlier in the year,

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(esearch )lanThe problem:The purpose of this pro0ect is to in)estigate the effects of different amounts of acid on the

curdling process of )arious types of cow+s mil-,

Independent variable:different types of cow+s mil- and different amounts of acidDependent variable:the amount of cheese produced due to the curdling process of the mil- with the

acidControls:the amount of mil- used and the temperature the mil- is heated toQuantitative measurement: weight 1in grams2Experimental and control groups: The control group for each mil- type is the cup with 3ero lemon 0uice

added, The experimental groups are the )aried amounts of lemon 0uice added

Materials:s-im mil-* 45 mil-* whole mil-* whipping cream* lemon 0uice* tap water* whis-* saucepan*thermometer* cheese cloth* strainer* scale* measuring cup* 46 plastic drin-ing cups* 7 clothespins* hanger*

newspaper* and $harpie pen, The different mil-s* cheese cloth* and lemon 0uice will come from the grocery

store, The -itchen items are from my -itchen, The scale is borrowed from my dad+s engineering company,Procedure: &or each of the different mil- types* the following steps were followed, !i)ide the cups into

sets of fi)e and label 6* 4* 8* 9* and 7, /eigh the empty cups and record in 0ournal, Add 8 68cups of mil-

into saucepan and heat on sto)e top to simmer 16;7< &2 while stirring with a whis- to a)oid mil- from

burning, /hen 6;7< & is reached* remo)e saucepan from sto)e top and pour warm mil- into each of the

cups to the mar-, /eigh cups again and ad0ust as necessary so that the weight of mil- in all cups is 67=grams, $ubtract the weight of the empty cups from the weight of the cups with the mil- to pro)ide the

weight of the mil-, Add =* 67* 47* 9=* and 77 drops of lemon 0uice to cups 6 through 7 and swirl, Allow the

mil- to cool for about 6> hours, eanwhile* cut the cheesecloth into e?ual si3es* and weigh each piece,

After the mil- has cooled* place a piece of cheesecloth 1folded o)er once2 into the strainer* and pour the

mil- o)er the cheesecloth so that the whey passes through* but the curds do not, &old the cheesecloth

containing the curds up from the corners* and hang the cheesecloth with a clothespin on a hanger to allow

the whey to continue to drain out onto newspaper o)ernight, /eigh the cheesecloth with the curds,$ubtract the weight of the cheesecloth to pro)ide the weight of the curds obtained,

/riting the research plan: Please follow the handout pro)ided

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Hypothesis: &or each of the different mil- types* the more drops of acid that are added* the more

curds will be produced,Also* the higher the percent mil- fat* the amount of curds produced will increase,esearch explanation: y hypothesis is explained from the research # conducted in which #

learned that the curdling process of mil- happens as a result of the changes in the structure of the mil-

protein* or casein* from the changes in the pH of the mil-, Adding lemon 0uice changes the acidity of the

mil- and therefore causes the mil- to curdle, As the protein structure of mil- changes due to acidification*

the casein begins to coagulate, Howe)er* the best form of mil- to use is fresh* raw mil- because it

contains bacteria that feed on the lactose* or the sugar in mil-* to form lactic acid, Along with lactic acid*

the acid added in acid coagulation of mil- will produce larger ?uantities of curds,#n the research* # also learned that cheese can be made from the mil- of different mammals, These

mil-s contain )arying amounts of fat, #n @"heese Primer* $te)en 'en-ins states that* @&at is important to

an indi)idual cheese+s character* but less important o)erall* since cheese can be made from mil- that is

full fat or reduced fat* or from s-im mil- that has )irtually no fat at all, #n his boo-* 'en-ins also explains

that* @(n a)erage* cow+s mil- contains 1by weight2 about C5 water* 8>5 protein* 8D5 fat* 75 lactose*

along with waterEsoluble )itamins*F,* and mineralsF Because of the permeability of the casein structure

and the changes that occur to the structure of casein during acidification* the higher the fat content of the

mil- used* the more fat may be trapped in the clumps that form in the coagulation of the mil-* whichincreases the percent of curds produced,

!ibliography:

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)urposeThe purpose of this project is to investigate the effect of different

amounts of acid on the curdling process of milk. This will be accomplished

by experimentation and comparative studies. This research will includeinformation about the cheese making process, different types of milk used

for cheese making, and the effect of acids on milk.

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'ypothesisFor each of the different milk types, the more drops of acid that are

added, the more curds will be produced.

The higher the percent milk fat, theamount of curds produced will increase.

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skim milk

!" milk

whole milk

whipping cream

lemon juice tap water

whisk

saucepan

thermometer

cheesecloth

strainer

scale

measuring cup

!* plastic drinking cups + clothespins

hanger

newspaper

harpie pen

%aterials

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)rocedureFor each of the different milk types, the following steps were followed.-ivide the cups into sets of five and label *, !, , /, and +.0eigh the empty cups and record in journal.

Add *1cups of milk into saucepan and heat on stove top to simmer #*2+3F$ while stirring with

a whisk to avoid milk from burning.0hen *2+3 F is reached, remove saucepan from stove top and pour warm milk into each of the

cups to the mark.0eigh cups again and adjust as necessary so that the weight of milk in all cups is *+4 grams.

ubtract the weight of the empty cups from the weight of the cups with the milk to provide theweight of the milk.Add 4, *+, !+, /4, and ++ drops of lemon juice to cups * through +.Allow cups to cool for about *hours.%eanwhile, cut the cheesecloth into e&ual si5es, and weigh each piece.After the milk has cooled, place a piece of cheesecloth #folded over once$ into the strainer, and

pour the milk over the cheesecloth so that the whey passes through, but the curds do not.Fold the cheesecloth containing the curds up from the corners, and hang the cheesecloth with a

clothespin on the hanger to allow the whey to continue to drain out onto newspaper overnight.0eigh the cheesecloth with the curds.ubtract the weight of the cheesecloth to provide the weight of the curds obtained.

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6onclusionThe results of my experiment are that the more lemon juice drops

are added, the more curds are produced. Also, the higher the milk fat

content of the milk there is, the more curds are produced .

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'ournal

$piral or composition noteboo-sGeep a hand written 0ournal to record dayEtoday

details of your pro0ect,

#nclude description of what needs to be done tocomplete experiment,"an be put in the bac- poc-et of binder

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!isplay Board

ust be ;6 cm tall* 646cm wide* and 8= cm deep

All information is neatly typed and organi3ed inprofessional manner,ust include 4 selfEgenerated items* such as graphs*

charts* models* pictures* or drawings,ust include:

Title Purpose Hypothesis aterials

Procedures !ata Results "onclusionAbstract

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(ral Presentations

Be prepared to present your pro0ect to the 0udges,

&i)e to se)en minute presentation including title and

purpose* and summari3ing procedures* data* results*

and conclusion,

%xpect ?uestions and answer with confidence,

!emonstrate clear communication s-ills,

aintain eye contact,

!isplay enthusiasm,