Biology Laundry Detergent Lab In New Zealand

Research Question:

Is there a difference in the effectiveness of New Zealand laundry detergents with or without enzymes when breaking down protein? 

 

 

 

 

 

Research Question: Is there a difference in the effectiveness of New Zealand laundry detergents with or without enzymes when breaking down protein? This is measured through the change in a 1.5 g  gelatin mass when exposed to three different laundry detergent brands (and their enzymes) over a period of 30 minutes.

Hypothesis: If the regular laundry detergents containing enzymes break down more gelatin mass (grams) than the organic detergent, then the regular laundry detergents are more effective. Today’s laundry detergents contain enzymes such as protease and amylase which break down proteins like that found in gelatin. This is because amylase found in enzyme-containing detergents catalyzes the breakdown of starch-based stains into smaller segments that make up the larger starch molecule. During the process of hydrolysis, protease catalyzes the breakdown of the peptide bonds that hold many amino acids together to form the protein molecule which is broken down into smaller polypeptides and amino acids. Therefore, regular detergents containing these enzymes is more likely to be more effective than the organic detergents which claim to contain no enzymes.

Background Information:

While THINK Global School spent a semester in Auckland, New Zealand, it was noticed that a there was a wide variety of laundry detergents available in the supermarkets. Mostly due to New Zealand’s popular, organic-consumer culture, several alternative detergents are sold in stores because these brands claim that their non-enzyme solution has the same—if not more— cleaning efficiency than that of its regular, competitor’s brands. Regular detergents contain organic surface-active, synthetic agents called surfactants. They minimize the surface tension of water, allowing the grease, dirt, smears to be acted upon by the enzymes thus removed[1].

Gelatin consists of protein chains that can be easily digested into amino acids. Gelatin is prepared from collagen, a protein found in animal skins and tendons (acquired during the meat collection process)[2]. When boiled, collagen decreases its mass and breaks its own protein bonds[3]. After being cooled, the collagen isn’t reverted back into its original state but becomes a gel, gelatin[4].

The purpose of this experiment is to observe and evaluate the effectiveness of organic and non-organic laundry detergents when breaking down protein through gelatin.

[1] Bajpai, Divya, and VK Tyagi. "Laundry detergents: an overview." Journal of oleo science 56 (2007): 327-40.

[2] "What is gelatin made of? | Frequently Asked Questions ..." 2013. 20 Feb. 2015 <http://www.peta.org/about-peta/faq/what-is-gelatin-made-of/>

[3] "What is gelatin made of? | Frequently Asked Questions ..." 2013. 20 Feb. 2015 <http://www.peta.org/about-peta/faq/what-is-gelatin-made-of/>

[4] "What is gelatin made of? | Frequently Asked Questions ..." 2013. 20 Feb. 2015 <http://www.peta.org/about-peta/faq/what-is-gelatin-made-of/>

Materials:

3x laundry detergents

         -1x organic (Earthwise ®)

         -2x regular (Fab ®, Persil ®)    

1x knife

1x chopping board

1x tweezers

Electronic balance (g)

5x 100ml (100cm3) beakers

Water (approximately 600 ml/ 200cm3  for each detergent solution)

Sheet of paper towels (as many as found necessary)

Pen

3x stirring rods

3x small, plastic kitchen bowls

1x 500cm3 beaker

Procedure:

1.      Separate the quantity Fab ® needed (approximately 5g of powder) by placing it in a plate.

2.      Measure detergent power’s mass on the electronic scale.

3.      Collect the 5 beakers (100cm3) and label them from 1 to 5,each according to which slice of gelatin will be placed within it later.

4.      In a kitchen bowl, pour the 5g of detergent together with 200ml of water using a 500cm3 beaker.

5.      Stir using the stirring rod until the detergent has dissolved into the water.

6.      Fill the 5 numbered beakers (100cm3), each with 50cm3of the solution. Make sure that the water measurement is accurate by bringing the beaker to eye level, as looking directly at the level of the water.

7.      Acquire the gelatin and cut 15 pieces, each with an approximate mass of 1.50g,  using the knife. Try to make the slices as accurate as possible and to do this cut the gelatin into several long and even rectangles. Then cut the rectangles into smaller pieces of similar width and length. Place them side by side to examine whether they are similar. 

8.      Separate the slices into group of 5 for each of the detergents.   

9.      Measure the mass of each individual gelatin slice. If there is excessive mass, use the kitchen knife to remove any additional pieces. Be sure to record the data on a table.

10.   Place 1 slice into each beaker and be sure to take note of which gelatin slice is in which beaker so that it is possible to accurately record the data. On a separate piece of paper, number the slice and place the paper underneath the beakers, lining up the data with the beaker.

11.   Allow the gelatin slices to soak in the solution for 30 minutes, to keep track of time use a stopwatch. Start the clock when the detergent solution is poured.

12.   Once the gelatin slices have soaked for 30 minutes, carefully remove each slice from their respective brakes one at a time using the tweezers. Do this with care, then dry the slice with the paper towel. Afterwards, place the slice on the electric balance and measure its mass. Record the data on the table. Repeat with each gelatin slice.

13.   Repeat this process for Persil ® and Earthwise ® detergents.

14.   Calculate the difference in mass of each gelatin slice before and after the 30 minute soak in the respected detergent solution. Record these calculations in the table.

 

 

Data Collection:

Table 1: Shows the changes in gelatin mass when a 1.5 g slice is exposed to regular laundry detergent, Fab ®.

Calculation example: Final mass of gelatin (g) - Initial mass of gelatin (g)= Difference between initial and final mass (g) 

Table 2: Shows the changes in gelatin mass when a 1.5 g slice exposed to regular laundry detergent, Persil ®.

Calculation example: Final mass of gelatin (g) - Initial mass of gelatin (g)= Difference between initial and final mass (g) 

Table 3:Shows the changes in gelatin mass when a 1.5 g slice exposed to organic laundry detergent, Earthwise ®.

Calculation example: Final mass of gelatin (g) - Initial mass of gelatin (g)= Difference between initial and final mass (g) 

Data Analysis:

Table 4: Shows the calculated mean difference of mass for the gelatin of Table 1, 2, and 3.

Graph 1: Shows the mean difference of efficiency for the three detergents by considering the mean differences of the final gelatin mass (g) after exposure to detergent solution .

Trends:

         In this experiment, it was notable that actually the organic detergent, Earthwise® was more efficient in the breakdown of the protein present in gelatin. It was also notable that the two non-organic detergents, Fab® and Persil®, were very similar in detergent efficiency. 

Comments:

The validity of the data and methodology can be questioned considering that the experiment was held in a high school laboratory, not a proper lab suited for complex experiments. A factor to take into consideration is water temperature which according to Laundry Temperature: Hot, Warm or Cold? is significant in the “cleaning process” and was an aspect that was not utilized in this experiment[1]. It was noticed that the larger amount of enzymes in a detergent , the more the gelatin’s mass decreased. This was a rule apart format he gelatin slice #1 in detergent 3, which seemed to decrease a significant amount, making it an anomalous result.

[1] "Laundry Temperature: Hot, Warm or Cold?." 2009. 20 Feb. 2015 <http://www.clean-organized-family-home.com/laundry-temperature.html>

Conclusion:

 

This experiment was an attempt to determine the effectiveness of laundry detergents containing enzymes and those without. It was expected that the laundry detergents containing enzymes would cause the gelatin in the beakers containing a regular detergent solution to have its protein broken down at a higher rate considering an average larger decrease in the gelatin’s mass after exposure, while the gelatin places in beakers containing organic/no enzyme detergent would have a smaller rate of protein breakdown considering an average smaller quantity of mass.

Three different groups of 5 gelatin slices were each submersed into different laundry detergents over a 30 minute time period. They were then removed from the solutions, re-weighed (grams) and the difference in mass was calculated.

The data showed, for the most part, that there were relatively small differences but no significant changes to the gelatin’s mass when under all three different laundry detergents. The larger amount of enzymes in a detergent , the more the gelatin’s mass decreased. This unclear trend between an in-differential protein breakdown between all three detergents (organic and non-organic) resulted because the conclusions of this experiment don’t support the claims of the manufacturer’s of these detergents.

The hypothesis of this experiment proved to be incorrect. The data clearly shows the gelatin masses activated in all three different detergents were not in accordance to the individual brands’ claims regarding the effectiveness of their products.

Evaluation: 

Questions for further research:

This lab work could be extended further by investigating the effect of different concentrations of the detergents on the rate of protein (gelatin) breakdown. This could enlighten one further as to if a higher concentration of enzymes results in an effective breakdown of gelatin in the same masses as in this experiment.

Another investigation could include the factors of water temperature together with detergents on gelatin. The exact same experiment would be conducted on another medium of analysis, showing the rate of protein breakdown brought on by enzymes to differentiate according to a variety of temperatures.

Works Cited

Bajpai, Divya, and V.k. Tyagi. "Laundry Detergents: An Overview." Journal of Oleo Science 56.7 (2007): 327-40. Print.

"Laundry Temperature: Hot, Warm or Cold?" Ms. Clean Jeans' Clean Organized Family Home. Web. 19 Feb. 2015. <http://www.clean-organized-family-home.com/laundry-temperature.html>.

"What Is Gelatin Made Of?" PETA. Web. 19 Feb. 2015. <http://www.peta.org/about-peta/faq/what-is-gelatin-made-of/>.