Effect of Fertilizer on the Survival Rate of Brine Shrimp

PURPOSE

The purpose of this experiment was to determine the effect of different amounts of fertilizer on the survival rate of brine shrimp.

I became interested in this idea last year when I did an experiment on the effect of oil on brine shrimp and wondered if fertilizers would affect brine shrimp. I have always been interested in fish and marine life. 

The information gained from this experiment could show farmers that synthetic fertilizers are harmful to our environment and that they should consider natural fertilizers.

HYPOTHESIS

My hypothesis was that as the amount of fertilizer in the water increased, the survival rate of the brine shrimp would decrease.

I based my hypothesis on the book Animal Care from Protozoa to Small Mammals, which stated that brine shrimp could digest small amounts of certain chemicals.

EXPERIMENT DESIGN

The constants in this study were:

•    The amount of brine shrimp in each test group

•    The containers the shrimp are in 

•    The amount of salinity in the water

•    The age of the brine shrimp

•    The type of water (well water) 

•    The type of fertilizer

The manipulated variable was the amount of fertilizer in the water.

The responding variable was the survival rate of the brine shrimp.

To measure the responding variable, I looked into the jars and when there was no movement in the jars, then all the shrimp were dead.                                                              

MATERIALS

QUANTITY	ITEM DESCRIPTION
About 4,000	Brine shrimp or brine shrimp eggs
4	Glass jars approx 1l each
5ml	Fertilizer
60ml	Saltwater powder
1	Brine shrimp Hatcher (if hatching eggs)
1	Milk jug (if hatching eggs)
1 bottle	Brine shrimp food
4	Petri dishes
1	Heat lamp

                     

PROCEDURES

1.    Hatch brine shrimp if needed: add 4ml of sea salt powder, the temperate should always be about 20-25 degrees Celsius, use the brine shrimp Hatcher to hatch the shrimp

2.    Make sure the heat lamp is always on

3.    Stir shrimp and then put an equal amount in 4 Petri dishes   

4.    Put 1 Petri dish of shrimp in each jar 

5.    Don’t do anything to the first jar of shrimp 

6.    Add 1ml. of fertilizer to the second jar

7.    Add 2ml. of fertilizer to the third jar

8.    Add 3ml. of fertilizer to the fourth jar 

  
9.    Observe how the brine shrimp react to the fertilizer

10.   Determine the survival/death rate of the shrimp after observation

11.    Record your findings in a journal 

12.    Feed brine shrimp every 24 hours

13.    Each evening repeat steps 9-12

14.    After 7 days graph your results

15.    Repeat steps 1-14 two more times

RESULTS

The original purpose of this experiment was to determine the effect of different amounts of fertilizer on the survival rate of brine shrimp

The results of the experiment showed the more fertilizer in the water, the faster the brine shrimp died. The brine shrimp in the control group lived the longest (7+ days average). The shrimp in group number 3 lived the shortest (1 day average). The brine shrimp in group number 2 took 2 days to completely die out on average. The brine shrimp in group number 1 lasted 3 days on average.

CONCLUSION

My original hypothesis was that as the amount of fertilizer goes up the number of brine shrimp would go down.

The results indicate that this hypothesis should be accepted, because the brine shrimp in-group 3 died out first and that was the group with the most fertilizer.

After thinking about the results of this experiment, I wonder if different types of fertilizer would affect them in the same way. In particular I would test natural fertilizers.

If I were to conduct this project again I would conduct many more trials to show better results.

Researched by --- Kolton W

Read More

Effect of Storage Temperature on the Deterioration

PURPOSE

The purpose of this experiment was to determine the effect of storage temperature on the deterioration of hop oil.

I became interested in this idea because I wondered if the temperature at which the hops were stored would have any effect on the amount of hop lupulin. 

The information gained from this experiment could help the Yakima economy and the hop industry by showing what temperature you should store the hops to keep the alpha at the level that customers want it, so the hops are useful for their products. 

HYPOTHESIS

My hypothesis was that the higher storage temperature would increase the deterioration of hop oil stored for 30 days. 

I based my hypothesis on a statement by SS Steiner Hop Company employee Jeremy Leker who said, “The cooler temperature the hops are stored at the longer it takes them to deteriorate.”

EXPERIMENT DESIGN

The constants in this study were:

•    Type of hops (Zeus)

•    Amount of oil in each sample

•    Storage temperature

•    Extraction method

•    Measurement method

The manipulated variable was the temperature in which the hops were stored.  

The responding variable was the amount of hop oil in the hop after being stored in a warehouse for one month. 

To measure the responding variable, I used a spectrophotometer. 

MATERIALS

QUANTITY ITEM	DESCRIPTION
1	70 degrees warehouse
1	20 degrees warehouse
3	Bags of Hops
1	Spectrophotometer
1	Pair of safety goggles
1	Meat grinder
1	1  Shaker
8	227 gram bags of hops
1	Scale
1	Produce bag
600	ml. Toluene

PROCEDURES

1)    Gather all materials.

2)    Take 227 grams hops that have been stored in a 10 degree Celsius warehouse for one month and grind them in a meat grinder 

3)    Run them through the meat grinder again

4)    Place the ground hops in a plastic produce bag

5)    Measure out five grams (plus or minus 0.02 of a gram) of the ground hops

A.    Using the metal scoop, scoop up small amounts at a time and place them into the jar that is on the scale until the weight reaches five grams

6)    Measure 100 ml of toluene into the jar with the ground hops

7)    Place the jar of hops and toluene into a shaker and turn it on 

8)    Let the shaker run for 30 minutes

9)    Using a pipette, measure out 100 ml of the mixed hop and toluene from the jar

10)    Transfer into a vial

11)     Transfer the vial mixture into the spectrophotometer to  measure the wave-lank of the hops and toluene

12)    Record the percentage of lupulin 

13)    Repeat steps 2-12 using hops that have been stored at 21 degree Celsius warehouse

14)    Repeat steps 2-13 3 times more, testing once a month

RESULTS

The original purpose of this experiment was to determine the effect of storage temperature on the deterioration of hop oil.

The results of the experiment were that after being in the room temperature warehouse for 30 days the hop alpha (amount of lupulin) deteriorated faster than in the cooler warehouse.  The average alpha in the hops after being stored in the 30 degree warehouse was 16.2% alpha.  The average deterioration after being stored in the 30 degree warehouse was 10.8%.  The average alpha in the hops after being stored in the 70 degree warehouse was 15.1% alpha.  The average deterioration after being stored in the 70 degree warehouse was 14.5%.  

CONCLUSION

My original hypothesis was that the higher storage temperature would increase the deterioration of hop oil stored for 30 days.  

The results indicate that this hypothesis should be accepted because after being in the room temperature warehouse for 30 days the hop alpha deteriorated an average of 14.5%.  After being in the cold warehouse for 30 days the hop alpha deteriorated an average of 14.5%.  

After thinking about the results of this experiment, I wonder if different varieties of hops would deteriorate faster or slower than zeus, especially at these same temperatures.  

If I were to conduct this project again I would have more samples.  I would also test the hops at more storage temperatures.  Another thing that I would do is continue the test for a longer time period.  

Researched by ----- Michelle U

Read More

Effect of Various Temperatures on the Type and Growth Rate of Bacteria in Meat

PURPOSE

The first purpose of this experiment was to determine the effect of temperature on the growth rate of bacteria in meat.

The second purpose of this experiment was to determine the effect of temperature on the types of bacteria that grow in meat.

I became interested in this idea when my mom would thaw out the meat in the sink then leave it there until we cooked it. I wondered how long it took the meat to spoil in different temperatures.

The information gained from this experiment could help homemakers and the food service industry protect people from food poisoning. Hospitals, schools, and restaurants would all benefit.

HYPOTHESIS

My first hypothesis was that the most bacteria would grow in the temperatures between 21° and 37° Celsius.

I based my first hypothesis on a statement made my the U.S Department of Agriculture's Meat and Poultry Hotline that said  “Bacteria grow most rapidly in the range of temperatures between 21° and 37°C. If the temperature is above 32°C, food should not be left out more than one hour.” 

My second hypothesis was that the four main types of bacteria that would grow were Staphylococcus aureus, Salmonella enteriditis, Escherichia coli O157:H7, and Campylobacter.

I based my second hypothesis on another statement made by the U.S. Department of Agriculture’s Meat and Poultry Hotline which said “leaving food out too long at room temperature can cause bacteria (such as Staphylococcus aureus, Salmonella enteriditis, Escherichia coli O157:H7, and Campylobacter) to grow to dangerous levels that can cause illness.”

EXPERIMENT DESIGN

The constants in this study were:

•  Amount of Meat

•  Temperatures Used

• Sterile knives and grinder

•  Autoclave

•  Incubator and incubation temperature

•  Petri Dishes

•  General test method

The first manipulated variable was the storage temperatures:

•  Freezing (0ºC)

•  Refrigeration (4ºC)

•  Room Temperature (20ºC)

•        Body Temperature (36ºC)

The second manipulated variable was the types of meat used.

•  Hamburger
•  Sausage
•  Steak
•  Chicken

The first responding variable was the amount of bacteria in the meat after storage.

The second responding variable was the type of bacteria that grew after storage.

To measure the responding variable I took the saline/meat "slurry" and spread it on the blood agar plates and incubated them for 48 hours. Then I took a colony count and identified the bacteria using the API 20 E procedures (see appendix.)

MATERIALS

Quantity	Items
15	Set of gloves
2	Incubators
1	Autoclave
1	Vortex
78	Petri dishes
4	Disposable Grinders
1	Saline Fluid
1	Pound of Beef
1	Pound of Chicken
1	Pound of Steak
1	Pound of Pork
80	Loop  Spreading tips
1	Freezing Temperature (0°C)
1	Refrigeration (4°C)
1	Body Temperature (36°C)
1	Room Temperature (20°C)
1	Lab coat
4	Sterile knifes

PROCEDURES

1.  Purchase approximately 5 ounces of four different types of meat

• Hamburger
•  Steak
•  Pork
•  Chicken

2. Go to the Yakima Valley Memorial Hospital

3. Wash hands

4. Put on lab coat and gloves

5. Prepare the sterile knife, grinder and scissors.

6. Cut one square inch meat out with sterile knife.

7. Cut meat into one square cm pieces and place in sterile grinder.

8. Grind for two minutes

9. Fill grinder with 50 ml. saline fluid

10. For one minute vortex the saline/meat “slurry”

11. Divide slurry into 4 different ten ml. containers

12. Discard leftover slurry in autoclave

13. Label each container with type of meat and number 

14. Place four containers in each temperature at hour zero

•  Freezing (0ºC)
•  Refrigeration (4ºC)
•  Room Temperature (20ºC)
•  Body Temperature (36ºC)

15. Take one slurry and add 10 micro L onto blood agar.

16.  Return slurry to storage temperature.

17. Spread with loop and place in incubator at time zero.

18. Label agar

19. Repeat steps 5 through 18 with each type of meat.

20. At hour 12 repeat steps 15 though 18.

21.  Repeat step 19 with each meat from each temperature at each hour

•  12 hours
•  24 hours
•  36 hours
•  48 hours

22. After the 48 hour incubation period remove plates from incubator

23. Count colonies with unaided eye under a white light and record. 

24. Autoclave all contaminated items 

25.  Follow procedures for Gram Stain from appendix on page 

26.  Identify types under microscopes

27.  Follow procedures “API 20 E” from appendix on page 

27. Wash hands.

RESULTS

The original first purpose of this experiment was to determine the effect of temperature on the growth rate of bacteria in meat.

The second purpose of this experiment was to determine the effect of temperature on the types of bacteria that grow in meat.

The results of the experiment were that Hamburger had the most bacteria at 0 hours and chicken had the least. Freezing all of the meats was more effective in limiting the growth rate of bacteria than storing the meats in any of the other temperatures. All meats grew the most in the 37 degree temperature at 48 hours and the least in 0 degrees centigrade temperature.

Pork had on average about 13 bacteria colonies at freezing temperature, 135 colonies at refrigeration temperature, 6000 colonies at room temperature, and 7563 colonies at body temperature. The types of bacteria on the meat were Aeromonas, Hydrophilia, Serratia, Non fermenting GNR, Serratia plymothica, and Staph Coagulant.

Chicken had, on average, about 13 bacteria colonies at freezing temperature, 27 colonies at refrigeration temperature, 1200 colonies at room temperature, and 4600 colonies at body temperature. Overall, the chicken had the least amount of bacteria colonies. The types of bacteria were Bacillus, Diptheroids-Skin flora, Staph Coagulent, and Escherichia Coli. 

Steak had, on average, about 90 bacteria colonies at freezing temperature, 260 colonies at refrigeration temperature, 9000 colonies at room temperature, and 9875 colonies at body temperature. The types of bacteria were Diphtherioids/Cat P, enterococci/Cat WR, Micro Coccus, and Serratia.

Hamburger had about 852 bacteria colonies at freezing temperature, 7275 colonies in refrigeration temperature, 12,125 colonies at room temperature, and 14,000 colonies at body temperature. Overall, Hamburger grew the most bacteria in any temperature. The types of bacteria were Micro coccus, Enterococci, Streptococcus ap, Serratia sp, Enterobacter cloacae, and Acinetobacter baumanii.

CONCLUSION

My first hypothesis was that the most bacteria would grow in the temperatures between 21° and 37° Celsius. The results indicate that my first hypothesis should be accepted. All the meats grew at a steady rate and had the most growth at 37°.

My second hypothesis was that the four main types of bacteria that would grow were Staphylococcus aureus, Salmonella enteriditis, Escherichia coli O157:H7, and Campylobacter.The results indicate that my second hypothesis was partially correct. We did find campylobacter, staphlylococcus and a strain of Escherichia coli but not Escherichia coli 0157:H7 or Salmonella. I rejected this hypothesis.

After thinking about the results of this experiment, I wonder what would happen if I did my procedures again with cooked meat. Would the bacteria content be completely different? Would we still find pathogenic bacteria?

If I were to conduct this project again I would make sure all my meats had the exact same “pull” dates. Also when I counted my bacteria colonies I would make sure I had more exact numbers instead of some estimations. I would use a more exact counting system for that, perhaps a microscope with a millimeter grid.

Researched by ---- SARAH S

Read More