data logging slide

8/8/2019 Data Logging Slide

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y Temperature affects the action of enzyme becauseincreasing temperatures (up to around 40 C) increasethe rate of reaction, by increasing the collision ratebetween the enzyme and substrate molecules (as in any

chemical reaction).y The highest rate of reaction is at the optimum

temperature for the enzyme.

y The rate of reaction then reduces as temperature

increases until, at some point, the reaction stopsaltogether. This is because at high temperatures (usuallyover 45 C), the protein structure of the enzyme isdenatured by heat. The molecule loses its shape and theenzyme is de-activated.


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1) Mix 0.4 gram of amylase enzyme, lipase enzyme andstarch powder with 20 ml of distilled water to dilutethe powder.

2) Pour 10 ml of diluted enzyme amylase and lipase in 2different test tube labeled A and B respectively.

3) Then, another1

0 ml of starch solution and oil werepoured into the same test tube A and B respectivelyand stir the mixture. Both the 2 test tube were placedin a big beaker filled with ice cubes at 0 C.


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4) pH sensors were placed in each test tube A and Bwhile 1 temperature sensor was placed in the beaker

filled with ice cubes to measure the temperature andpH increase.

5) Heat the beaker with high fire and as the ice cubes

melts, the temperature increases.

6) Obtained result are recorded in a table and atemperature ( C) against pH graph is plotted.


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y TABLE


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Time(s)

0 200 400 600 800 1000 1200 1400 1600 1800

0

5

Temperature ( C) against pH

NOTE : Enzyme lipase

: Enzyme amylase

: Temperature


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QUESTION

Why do we use reactant such as starch and oil in thisexperiment.

Based on the graph, identify the optimum temperature and

pH for enzyme reaction to occur?

Lipase

amylase

How do we relate pH effects on the enzyme activities?

Why different enzyme have different pH?

How does temperature effect the enzyme activities?


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Enzyme activity can lead to the deterioration of foodquality. Enzymes present in animals, vegetables and fruitpromote chemical reactions, such as ripening. Freezingonly slows the enzyme activity that takes place in foods. It

does not halt these reactions which continue afterharvesting. Enzyme activity does not harm frozen meats orfish and is neutralized by the acids in frozen fruits. Butmost vegetables that freeze well are low acid and require abrief, partial cooking to prevent deterioration. This is

called "blanching." For successful freezing, blanch orpartially cook vegetables in boiling water or in a microwaveoven. Then rapidly chill the vegetables prior to freezing andstorage.


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Experiment can bestopped, pause andrestart at any time

in case if erroroccur.

The pattern of pH,temperature andtime changes canbe observed along

with theexperiment

data logging slide

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