Emad Ahmed Chem 108 Formal Lab

Chem 108 Spring 2009 Date of experiment: 3/19/09 Date of submission: 4/2/09

Experiment #7: Analysis of Percent Fat in Chips

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Abstract : The purpose of the experiment was to analyze the mass percentage of fat in both regular and fat-free Pringle potato chips. The efficiency of fat extraction was also determined for each trial.

Fat extraction by petroleum ether was the method used by which the mass percentage of fat in the chips was determined. Petroleum ether, a solvent that dissolves only fat as opposed to salts and carbohydrates, was mixed with tiny particles of chips. The pa rticles then removed, the pet ether was then left to boil away awa y, leaving behind residue fat.

c laims of Introduction : The reason for analysis of fats in chips was due to health concern and claims “fat free chips”. When potato chips are being produced, fat is added. Normally, potatoes do not contain fat. Currently, heart attacks and heart disease are the leading cause of death for men and women world wide. To find out how much fat the chips contained, fat extraction was performed by petroleum ether. Petroleum ether, a solvent that dissolves only fat as opposed to salts and carbohydrates, was mixed with tiny particles of chips. Particles then removed, the pe t ether was then left to boil away, away, leaving behind residue fat. The expected result of the experiment would be to determine a fat percentage, in both regular and fat-free Pringle chips, that is true to the chip label information on the container. Thus, expected results would be 17% fat for regular Pringles, and 0% fat for fat-free Pringles. Sample

Regular Pringles

Fat Free Pringles

%Total Fat 17 % Serving Size (in grams) Total Fat (in grams) 28 g Theoretical % fat in chips 11 g

0% 28 g

39 %

0%

0g

This table above shows the information from the label of the chip’s carton. It is important to review this because it shows the amount of fat and other nutrition facts. The 17% “total fat” from the label above ab ove refers to the amount of fat in the product compared to the amount needed for a 2,000 calorie diet. The actual amount a mount of fat in the chips is 11 g, or 39% of total 28 g serving size (Ref. 2)



Yau (Ref. 1) was followed. Experimental Procedure : The procedure described by Yau

Data & Observations :

Data from nutrition label

Regular Pringles 17 %

Fat Free Pringles

28 g

28 g

11 g

0g

39 %

0%

Fat Free Pringles

Mass of crushed chips (g)

Regular Pringles 0.5416 g

Mass of empty Erlenmeyer Flask (g)

39.143 g

41.359 g

Mass of Flash + fat residue

39.348 g

41.460 g

Mass of fat residue

0.205 g

0.101 g

% Fat in chips

37.85 %

27 %

%Total Fat Serving Size (g) Total Fat (g) Theoretical % fat in chips

Data from experiment

0%

0.364 g

Calculations & Results :

Percent theoretical fat = (Mass of fat / Mass of sample) x 100 = (11 g / 28 g) x 100



= 0.205 g Mass of fat residue (fat-free Pringles) = (41.460g – 41.359g) = 0.101 g % Fat in chips (regular Pringles) = (0.205g / 0.5416g) x 100 = 27 % % Fat in chips (fat-free Pringles) = (0.101g/0.364g) x 100 = 37.85 %

Summary of Results and Discussion :

I.

Discussion of Class Results :

See attached Class Results Table printout. The table shows ex perimental trials from the entire class. There are a few outliers—irregular results that stand out among the rest— such as Student 5, Student 12, Student 14, Student 16 and Student 18. The average percent fat, adjusted for outliers, was 27.4 % Average Percent Fat = (Total % Fat of All Trials) / Number of trials) = ( (23.9 + 29.0 + 28.7 + 29.7 + 23.5 + 30.4 + 31.6 + 28.1 + 27.8 + 32.8 + 34.0 + 27.2 + 30.4 + 21.0 + 21.0 + 18.8 +27.9) / 17) = 27.4% Efficiency of Extraction = (Experimental % Fat / Theoretical % Fat in Chips ) x 100 = ( 27.4 / 39 ) x 100 = 70.2 %



All experimental trials showed that the fat-free Pringles have substantial fat in them. The fat-free Pringle chips contain Olestra, a fat substitute which is indigestible by the bod y but shows up as fat residue in the experiment. Olestra is added, because to cook, or bake, chips, oil is needed. The process of baking ba king chips requires fats. Olestra is a fat, this it shows up as fat in our experiment, ex periment, but it is indigestible. The fat that appeared from fatfree chips appeared to be opaque. Too Too much Olestra in food can cause negative side effects such as diarrhea, upset stomach, etc.

II.

Error Analysis:

There are many causes for error in this experiment. One could be that while crushing chips, some of the chips were left in the mortar, thus reducing the fat percent considerably. considerably. Another could be to let the pet either boil away for too long. That would reduce fat percentage as well. One of the more common mistake that a lot of individuals made was probably the absorption of tiny chip particles through the glass dropper into the beaker. That would increase the measured mass of the beaker, thus indicating an increased amount of fat percentage.

Conclusion :

“Fat-free” chips do in fact contain fat, although it is 10% less than regular Pringle chips. There is 27.7% fat in fat-free chips.

References:

Laboratory,; 1. Yau, C. L. Chem 108 Experiments in Fundamentals of Chemistry Laboratory,; Academx: Baltimore, MD, 2007; pp 64-65 2. "NEWS: DA Approves Approves at Substitute." FDA. 26 2 6 Jan 1996. 4 Apr 2009 .

Emad Ahmed Chem 108 Formal Lab

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