Thursday, December 5, 2013

Food and Science

While watching a video about a food scientist at NASA, i noticed a few videos about food and science. These are videos about lectures at Harvard University and i found them interesting. I only saw two hours of these videos, but i'll check the rest out another time.

Food and Science | Lecture 1 (2012)

https://www.youtube.com/watch?v=_Ft0cwxjBKE

Food and Science | Lecture 2 (2012)

https://www.youtube.com/watch?v=cvbcOA2ZVog

Michele Perchonok: Food Scientist at NASA

http://www.ift.org/Knowledge-Center/Learn-About-Food-Science/Day-In-The-Life/Michele-Perchonok.aspx

Michelle is a food scientist at NASA and this upcoming award winning video is all about her and her profession: https://www.youtube.com/watch?v=4wAC-ST77Ow

Sustainability

http://www.ift.org/Knowledge-Center/Learn-About-Food-Science/World-Without-Food-Science/Sustainability.aspx

In a world without food science, much of the food produced would be lost to spoilage and waste. Food scientists work to conserve resources during the entire chain of production. They make sure land and water are conserved and protected as a crop is grown and as a food product is made. They create packaging that is reduced, recycled and reusable to minimize waste. They place food production plants in areas where food can be transported and distributed efficiently.

Here's a video:

https://www.youtube.com/watch?v=HqTJdDBQtvw

World Without Food Science

http://www.ift.org/knowledge-center/learn-about-food-science/world-without-food-science.aspx

World Without Food Science™ is a public education campaign created by the Institute of Food Technologists to generate awareness of the role that food science plays in ensuring a nutritious, safe and abundant food supply.

This awareness initiative is designed to help the public understand where their food comes from so they can make informed decisions about the food they eat every day. As part of this effort, IFT provides practical consumer tips at www.iftfoodfacts.org.

History of Food Science

http://www.ift.org/knowledge-center/learn-about-food-science/what-is-food-science/history-of-food-science.aspx

Nurtured by the Institute of Food Technologists, food science and technology has evolved over many decades into a multidisciplinary field that has been instrumental in the development of a safe, affordable, and abundant food supply. Learn how our food science profession has advanced the science of food and benefitted humankind through three historic publications:

A Century of Food Science
Booklet published in 2000 covering developments in food technology and the food industry.

Food Technology magazine’s 50th Anniversary
Article on the 50th anniversary of Food Technology magazine (1997).

IFT's 50th Anniversary Issue
Complete September 1989 issue with a variety of food technology review and history articles.

What Is Food Science & Technology?

http://www.ift.org/knowledge-center/learn-about-food-science/what-is-food-science.aspx

Food Science

Food science draws from many disciplines such as biology, chemical engineering, and biochemistry in an attempt to better understand food processes and ultimately improve food products for the general public. As the stewards of the field, food scientists study the physical, microbiological, and chemical makeup of food. By applying their findings, they are responsible for developing the safe, nutritious foods and innovative packaging that line supermarket shelves everywhere.

Food Technology

The food you consume on a daily basis is the result of extensive food research, a systematic investigation into a variety of foods’ properties and compositions. After the initial stages of research and development comes the mass production of food products using principles of food technology. All of these interrelated fields contribute to the food industry – the largest manufacturing industry in the United States.

Experiment 3: Enzymatic Browning of Apples

http://www.ift.org/Knowledge-Center/Learn-About-Food-Science/K12-Outreach/Food-Science-Experiments/~/media/Knowledge%20Center/Learn%20Food%20Science/Enzymes%20in%20Food%20Systems/StudentGuideAPPLES.ashx

pdf link to directions

Experiment 2: Determining Changes in Plant Pigments with Blanching

Experiment 1: Testing for Catalase Activity

Experiment 1: Effect of Heat and pH on Color and Texture of Green Vegetables

http://www.ift.org/Knowledge-Center/Learn-About-Food-Science/K12-Outreach/Food-Science-Experiments/Enzymes-in-Food-Systems-Experiments.aspx

This is the pdf link to the experiment and its basically everything a student needs to do in order to complete the experiment and get a result.

How Does Diet Affect Your Body Temperature?

http://www.education.com/science-fair/article/does-diet-affect-body-temperature/

Research Questions:

Can diet change basal body temperature?
Which foods can change the temperature of my body?

Certain elements in a diet are believed to be able to increase a person’s basal body temperature and, as a result, improve metabolism. This experiment will evaluate whether simple diet modifications are truly able to increase body temperature.

Materials:

Basal thermometer
Coconut oil and other temperature-elevating food you identify in your research
Notebook for recording and analyzing results

Experimental Procedure:

Record your basal body temperature each morning when you wake up. Be sure to take your temperature before getting out of bed. Record temperatures for approximately 2 months to get an accurate view of your average basal body temperature.
Research diets believed to increase basal body temperature. For example, you should be sure to drink plenty of fluids, cook with coconut oil, increase protein intake, and eat complex, high-fiber carbohydrates.
Follow your new diet for approximately 2 months.
Record your basal body temperature each morning for the duration of the experiment.
Analyze your results. Do you notice changes in your body temperature after beginning your new diet? How quickly do changes take place? Does your temperature return to its starting level when you stop the diet?

An experiment is coming its way

Some info: i want to do an experiment on "Is a denser fruit healthier?"

http://www.whfoods.com/foodstoc.php

1. The World's Healthiest Foods are the Most Nutrient Dense

The World's Healthiest Foods have been selected because they are among the richest sources of many of the essential nutrients needed for optimal health. We used a concept called nutrient density to determine which foods have the highest nutritional value.

Nutrient density is a measure of the amount of nutrients a food contains in comparison to the number of calories. A food is more nutrient dense when the level of nutrients is high in relationship to the number of calories the food contains. By eating the World's Healthiest Foods, you'll get all the essential nutrients that you need for excellent health, including vitamins, minerals, phytonutrients, essential fatty acids, fiber and more for the least number of calories.

But according to another student who has made a prezi on this same experiement, results are different.

http://prezi.com/-b1jnnqvkbr-/is-denser-fruitvegetables-healthier-by-sydney-bair/

Basically, his/her results were that denser fruits were not healthier.

So, who to believe? the internet or someone who has done their math homework on all this? I'll just have to find out myself soon enough.

http://msue.anr.msu.edu/news/choose_fruits_and_vegetables_as_a_nutrient-dense_food

Choose fruits and vegetables as a nutrient-dense food

Eat fruits and vegetables as a nutrient dense food to get many of the nutrients your body needs to stay healthy, without adding lots of calories.

Fruits and vegetables are a primary food choice when you are looking to buy nutrient dense foods (foods high in nutrients and low in calories).

Tuesday, November 12, 2013

Conclusion for my strawberry experiment over the summer

Conclusion:

My experiment didn't turn out like how I thought it'd be. The hypothesis is correct, because I did look up research and found out that when frozen strawberries are used in dessert, they do lose flavor after being defrosted in water. Why? Because of the formation of the ice crystals in frozen berries. When water freezes, it expands forming crystals. These ice crystals cause most of the cells to burst by poking holes in the walls of others. When thawed, these walls don't repair themselves, therefore resulting in a mushier strawberry. With my experiment, I couldn't compare the store bought strawberries that were made with the shortcake with the frozen strawberries because the directions I followed made the shortcake a failure and it was all a mess. Many errors were made in this experiment. Some of these errors included: lack of materials, hard to work with dough, recipe wasn't clear enough, unnecessary ingredients were mixed in, etc. But its okay to make mistakes and fail a few times. Because of how this experiment turned out awfully, it gave me even more ideas on what other types of experiments I can do through out the year and what errors I should avoid making.

Thursday, October 31, 2013

Is it possible to make Jello using fresh pineapples instead of canned pineapples?

http://www.all-science-fair-projects.com/project484_39.html

MATERIALS:

Fresh pineapple, 1 (can be frozen and used later)
Canned pineapple, 1
Jello , 2 small boxes any flavor
Bowl, 1
Boiling & Cold water, 4 cups each
Spoon, 1
Paper cups
Knife, 1

PROCEDURE:
If students will eat the gelatin desserts, follow standard sanitary precautions. This is intended to be a demonstration lesson.

Cut the fresh pineapple into cubes.
Make Jello according to instructions on box.
Put one piece of canned pineapple into half of the paper cups and one piece of fresh pineapple into the other half of the cups.
Refrigerate until set. It usually takes longer than one period.
Assign homework: "Which Jello would you like tomorrow and why?" or some sort of variation on that theme.
Serve and observe.
Follow-up question: "What is meat tenderizer and what does it do?"

How does heat affect the coagulation of eggs?

http://www.all-science-fair-projects.com/project493_39.html

Procedure:

Scald milk in double boiler.
Beat egg slightly (white and yolk should be thoroughly mixed but not foamy.)
Stir sugar and salt gradually into egg.
Pour scalded milk into egg-sugar mixture, stirring constantly.
Add 1/4 tsp. vanilla and stir.

Pour the mixture into two custard cups and cook according to the directions given below for the appropriate treatment. Each formulation makes 2 custards. Your TA will help members of your group decide which treatments to make. Each group should make all treatments.

Preparation of custards.

Oven Control
1. Preheat oven to 350°F.
2. Prepare custard mixture as directed above.
3. Set custard cup in a Pyrex baker as deep as the custard cup.
4. Fill the baker with hot water to the level of the custard in the cup. Place in oven.
5. Bake until the tip of a sharp knife inserted halfway between the center and edge of the custard comes out clean. (Approx. 40-50 min.)
6. Remove immediately from hot water and place on a rack to cool, then evaluate custard.
Oven Variation:

Into a 350°F oven as in the Oven Control but without doing Step 4. Remove when a knife inserted into the custard comes out clean. Record the baking time.
2 Egg Variation: (bake in an oven as in Oven Control.)

Prepare custard according to the basic mixture, using 96 g of whole egg (2 eggs).
Microwave

Cover the custard cup with plastic wrap. Poke a few holes in the plastic to allow steam to escape. Adjust microwave time and power to get the best product you can.

What factors affect the yield and composition of meat after cooking?

http://www.all-science-fair-projects.com/project488_39.html

. Procedure

Shape 120 grams of ground beef into a round patty 1.0 cm. thick. (This is a rather thin patty.)
Cover part of a broiler pan with aluminum foil and poke holes in the foil to let the fat drip through.
Turn on the broiler in the oven and place the broiler pan in the oven so the top of the meat is about 9 cm. from the coil. (This will probably be the second rack slot down.) Leave the door of the oven part way open.

Cook the patty until either medium or well-done.

	Medium-done - broil until the center of the patty is a pinkish-brown color (about 10 min. - 5 min. on each side.)
	Well-done - broil until the center of the patty has no evidence of pink (about 16 min. - 8 min. on each side)

Weigh the cooked patty immediately after cooking, place on a plate and cut in half.
Calculate yield percent as follows: (cooked weight/starting weight) x 100
Report yield and observe color and firmness. Tasting is not necessary and not advisable for the medium-done patties.

How does the sugar concentration vary in different brands of apple juices?

http://www.all-science-fair-projects.com/project873_39.html

Materials

Quantity Item Description

5 mL of the following nine juices:

-Martinelli's Apple Juice

-Juicy Juice Apple Juice

-Washington's Natural Apple Juice

-Seneca Apple Juice

-Minute Maid Apple Juice

-Tree Top Apple Juice

-Tree Top Apple Raspberry Juice

-Tree Top Apple Grape Juice

-Tree Top Apple Pear Juice

1 Pair of Scissors

9 HPLC Vials

9 HPLC Vial Lids

9 Disposable Glass Pipettes

1 Pipette Bulb

1 Carousel

1 High Pressure Liquid Chromatograph

9 Straws

1 Automatic Refractometer

Procedures

High Pressure Liquid Chromatograph:

1. Go to the store and buy all juice.

2. Go to the lab and gather all materials.

3. Label all the juice with numbers.

4. Label all the HPLC vials with the corresponding numbers.

5. Open the first juice and use a glass pipette to fill the HPLC vial

about 2/3 full of juice.

6. Get a new glass pipette and repeat step 5 for the remaining eight

juices.

7. Screw the lids on the HPLC vials and put them into the carousel.

8. Put the carousel into the High Pressure Liquid Chromatograph

and push start.

Refractometer:

1. Stick a straw into the juice, clamp thumb over the end of the straw

and pull it out.

2. Bring the straw over the refractometer and take the thumb off the

end of the straw (juice should drip out).

3. Push Run and record the data.

4. Clean off the refractometer with Kimwipes®.

Get a new straw and repeat steps 1-4 for the rest of the juice.

Levels of carbohydrates in different varieties of milk

http://www.all-science-fair-projects.com/project1150_39.html

-    13g of non-fat powdered milk
-    100ml of soy milk
-    3 beakers
-    1 hot plate
-    1 thermometer
-    1 bottle 10% acetic acid
-    1 stirring rod
-    12 grams of calcium carbonate
-    Water
-    6 pieces of filter paper
-    300ml of ethanol
-    3 Erlenmeyer flask
-    1 digital weighing scale

Procedure

1.    For this science fair project, the independent variable is the type of milk used. The dependent variable is the amount of lactose crystals formed, which will be determined by weighing the crystals with a digital weighing scale. The constants (control variables) are the temperature of the environment (which will remain at room temperature), the amount of milk used and the process of extracting the lactose.

2.    Label the 3 beakers as milk, powder milk and soy milk. Label the 3 Erlenmeyer flasks in the same way.

3.    Pour the low fat milk and soy milk into their respective beakers. In the last beaker, mix 13g of powdered milk into 87ml of warm water. Place the 3 beakers on a hot plate, and bring the temperature of the liquids in the beakers to 55°C. Check the temperatures with a thermometer.

4.    While stirring the milk in the beakers, add drops of acetic acid till the liquids turn colourless and a mass of casein protein forms in each beaker.

5.    Remove the casein and add 4 grams of calcium carbonate to the remaining clear liquid in each beaker. Stir for a few minutes.

6.    Increase the temperature of the hot plate to bring the liquid in the beakers to a boil. Stir the liquid in each beaker with a stirring rod. The remaining proteins will precipitate. Filter the solutions into their respective Erlenmeyer flasks and continue heating until only 25ml of solution is left.

7.    Add 100ml of ethanol to the 25ml of solution in each Erlenmeyer flask, and allow to cool. Filter the liquids again. Heat the liquids in their Erlenmeyer flasks, then allow to cool slowly.

8.    As the solutions cool, lactose crystals will form in each Erlenmeyer flask. Collect these crystals and measure their weights with the digital weighing scale. Record each measurement in a table, as shown below.

Effectiveness of garlic in fighting bacteria

http://www.all-science-fair-projects.com/project1098_39_2.html

300ml milk
1 measurement cup (to measure 100ml of milk)
5 pieces garlic ground and juice extracted( approximately 5ml)
3 test tubes
4 syringes
Escherichia coli (E. Coli) specimen
2 tooth picks
1 permanent marker pen

Procedure

1. For this experiment, the independent variable is the composition of the test specimen. The dependent variable is the growth of the bacteria colony. This is determined by measuring the size of the growth using a ruler. The constants (control variables) are the room temperature, the amount of sunlight and the ingredients in the petri dish agar.

2. The petri dish prepared with the blood agar must be stored in a refrigerator. Before the start of the experiment, remove the petri dish from the refrigerator to allow it to reach room temperature.

3. Three test specimens are made and labeled as described below:

4. Specimen A - 100 ml of milk is measured using the measuring cup and poured into test tube A. With the marker pen, label this test tube A

5. Specimen B - 100 ml of milk is measured using the measuring cup and poured into test tube B. With the marker pen, label this test tube B. Using a toothpick, add a small amount of E. Coli specimen to test tube B. Shake the test tube to mix the specimen thoroughly.

6. Specimen C - 100 ml of milk is measured using the measuring cup and poured into test tube C. With the marker pen, label this test tube C Using a toothpick, add a small amount of E. Coli specimen to test tube C. Next, add the extracted garlic juice to test tube C. The test tube is shaken to mix the specimen.

7. The specimens in test tubes A, B and C are allowed to incubate for 2 hours.

8. Mark the 3 petri dishes - A, B and C. Remove the lid and using the syringe, extract 10 ml of the sample mixture from test tube A and place it in the center of petri dish A.

9. Use a new syringe to extract a 10 ml sample from test tube B and place it in dish B and repeat for test tube C/dish C.

10. Replace the petri dish lids and store the petri dishes in a cool and shaded place.

11. The diameter of the E. Coli colony is measured everyday for 5 days and recorded in the table below.

These are just ideas

I've been very busy with college applications, school, SAT's and job searches lately. But as soon as i am done with it all, i'll be trying out some of the experimental procedures i listed today.

Which Orange Juice Has the Most Vitamin C?

http://www.sciencebuddies.org/science-fair-projects/project_ideas/Chem_p044.shtml#materials

Orange Juice Titration Kit (1). Includes:
- Juicer for extracting juice from oranges
- Cheesecolth
- Vitamin C tablets, 250-mg
- Masking tape
- Permanent marker
- Chemical splash goggles
- 2% Lugol's iodine solution (30 mL); also available from Amazon.com
- Soluble starch (30 g)
- Small funnel (do not use for food after using it for chemistry)
- 50 mL graduated cylinder
- 500 mL graduated cylinder
- 50 mL Ehrlenmeyer flask
- 50 mL burette
- Ring stand
- Burette clamp
- Lab apron
- Eyedropper (a transfer pipette or medicine dropper would work too)
- Nitrile gloves (rubber or latex would work too)
- Measuring spoons (a balance accurate to the 0.1 gram would also work)
- 100 mL beaker
- Glass bottle, amber. Iodine is light sensitive and needs to be stored, once mixed, in an amber glass bottle or in an aluminum foil covered bottle.

You will also need to gather these items:

Samples of three different kinds of orange juice:
- Home-made fresh-squeezed (which means you'll need to buy some oranges)
- Premium not-from-concentrate juice (e.g. Tropicana® or Florida's Natural®)
- Made from frozen concentrate (following instructions on the concentrate can)
Distilled water; available in the bottled water section of most grocery stores

Do your background research so that you are knowledgeable about the terms, concepts, and questions, above.
Wear gloves, chemical safety goggles, and a lab coat or apron when using the iodine solutions in this experiment.
Dilute the Lugol's solution 1:10 in distilled water to make your iodine titration solution.
1. Pour the 30 mL Lugol's solution into the 500 mL graduated cylinder.
2. Add enough distilled water to bring the total fluid volume to 300 mL and mix.
3. Store the solution in a clean, tightly covered glass jar that is clearly labeled. Store it in a location that is protected from light.
4. Rinse and dry the 500 mL graduated cylinder.
Make a starch indicator solution.
1. This can be anywhere from 0.5 to 1.0%. The exact amount of starch is not critical.
2. For a 0.5% solution, add 1 g (which is equivalent to 1/4 teaspoon) of soluble starch to 200 mL of near-boiling distilled water.
3. Stir to dissolve, and allow to cool.
4. When cool, store the starch solution in a clean, tightly covered glass jar that is clearly labeled.
5. Rinse and dry the 500 mL graduated cylinder.
Make a fresh vitamin C standard solution (1 mg/mL). Do this on each day that you make vitamin C measurements from orange juice.
1. You will use this solution to "standardize" your iodine titration solution. You will measure how much of your iodine solution it takes to oxidize a known amount of vitamin C. You can then use your iodine titration solution to determine the amount of vitamin C from test samples of juice from oranges.
2. Crush a 250 mg vitamin C tablet, and dissolve it in 100 mL of distilled water.
3. Pour into a graduated cylinder and add distilled water to bring the total volume to 250 mL.
Titrate 25 mL of vitamin C standard solution.
1. Use a clean 50 mL graduated cylinder to measure 20 mL of vitamin C standard solution.
2. Pour this into a 50 mL Ehrlenmeyer flask (the shape of this flask allows you to swirl the solution to mix it without spilling).
3. Add 10 drops of starch indicator solution.
4. Set up the 50 mL buret on the the ringstand.
5. Use a funnel to carefully fill the buret with your iodine titration solution. Tip: the fluid level should not be past the graduated markings on the buret.
6. Write down the initial volume of the iodine titration solution in the buret.
7. Place the Ehrlenmeyer flask (containing the vitamin C and starch solutions) under the buret.
8. Carefully release the spring clamp of the buret to add iodine solution drop by drop.
9. Swirl the flask to mix in the iodine solution after each addition.
10. The titration is complete when the iodine creates a blue-back color in the solution that lasts for longer than 20 seconds.
11. Record the final volume of the iodine solution in the buret.
12. The difference between the initial volume and the final volume is the amount of iodine titration solution needed to oxidize the vitamin C.
13. Repeat this step three times. You should get results that agree within about 0.1 mL.
Here's how to prepare fresh-squeezed orange for testing.
1. Use a juicer to squeeze orange juice from two (or more) oranges.
2. You need 20 mL of juice per titration, and you should do at least three titrations per storage condition, for a total of 60 mL.
3. Filter the orange juice through cheesecloth to remove any pulp and seeds.
Titrating an orange juice sample is quite similar to titrating the vitamin C standard. Here are the steps:
1. Tip: if any of the orange juice samples contain pulp, filter them through clean cheesecloth before doing the titration.
2. Use a clean 50 mL graduated cylinder to measure 20 mL of the fresh-squeezed juice.
3. Pour this into a 50 mL Ehrlenmeyer flask (the shape of this flask allows you to swirl the solution to mix it without spilling).
4. Add 10 drops of starch indicator solution.
5. Set up the 50 mL buret on the the ringstand.
6. Fill the buret nearly full with your iodine titration solution.
7. Write down the initial volume of the iodine titration solution in the buret.
8. Place the Ehrlenmeyer flask (containing the vitamin C and starch solutions) under the buret.
9. Carefully release the spring clamp of the buret to add iodine solution drop by drop.
10. Swirl the flask to mix in the iodine solution after each addition.
11. The titration is complete when the iodine creates a distinct color change in the juice/starch solution. This color change will be harder to see than with the vitamin C solution, since the juice starts out orange. The color will change from orange to grayish brown when the endpoint is reached. If you continue to add iodine, the color will darken further. You want to note the volume of iodine added when the color first changes.
12. Record the final volume of the iodine solution in the buret.
13. The difference between the initial volume and the final volume is the amount of iodine titration solution needed to oxidize the vitamin C.
14. Repeat this step three times. You should get results that agree within about 0.1 mL.
For each juice (fresh, premium, or from-concentrate), calculate the average amount of iodine needed to titrate a 20 mL sample.
You can calculate the amount vitamin C in your samples by setting up a proportion. Here's an example (with made-up numbers) to show you how:
1. Let's say that it took an average of 8.5 mL of iodine solution to titrate 20 mL of 1 mg/mL vitamin C standard solution, which means 20 mg vitamin C total.
2. Let's also say it takes an average of 6.8 mL of iodine solution to titrate a 20 mL test sample of orange juice.
3. We'll call the amount of vitamin C in the orange juice sample x. You can find what x is with the following equation:
  
  X = (6.8 mg/ml)*(20 mg)/(8.5ml) = 16.0 mg
Did one type of orange juice have more vitamin C than the others? Can you explain your results?

From Bitter to Sweet: How Sugar Content Changes in Ripening Fruit

http://www.sciencebuddies.org/science-fair-projects/project_ideas/FoodSci_p063.shtml#materials

Materials and Equipment

Bananas, unripe (5 per trial; 3 trials)
Metal dinner fork and knife
Dinner plate
Cheesecloth
Scissors
Refractomete

To begin, collect five unripe bananas. Choose five bananas that are similar in size and that are all unripe. The bananas should be as similar to each other as possible. The pieces of fruit should be unripe when you take your first reading at the start the procedure and very ripe for the last reading.
Read the directions that came with your refractometer.
On the day you purchase them, cut off a section of one of the unripe bananas that is about 3 inches in length.
Place the banana section on the plate and mash it thoroughly with a fork.
Cut a 6-inch square of cheesecloth.
Place about one-third of the chopped banana in the cheesecloth and squeeze out a few drops of juice onto the lens of the refractometer.
Squeeze slowly so that the juice has time to flow through the cloth. As an alternative, you can wipe the surface of the wet cloth on the glass of the refractometer.
Read the sugar content of the unripe banana. Record the data in a data table in your lab notebook. Be sure to note the trial number, condition of the fruit, date, and sugar content (in Brix). Discard the fruit in the cheesecloth.
Repeat steps 4–7 with the remaining freshly mashed banana two more times. Use new cheesecloth and banana for each reading. You should have three separate readings for each piece of fruit.
Repeat steps 4–7 for the remaining pieces of fruit, as they ripen, as follows. Note: You might want to modify the days on which you take your Brix readings, depending on how quickly the fruit is ripening.

Day 2: Test the second piece of fruit.
Day 4: Test the third piece of fruit.
Day 6: Test the fourth piece of fruit.
Day 8: Test the last piece of fruit.

Perform the entire procedure two more times. This demonstrates that your results are repeatable. The tests can be run concurrently.
Average the degrees Brix for each day and record these numbers in your lab notebook.
Graph the time, in days, on the x-axis and the degrees Brix on the y-axis.

Do Oranges Lose or Gain Vitamin C After Being Picked?

http://www.sciencebuddies.org/science-fair-projects/project_ideas/Chem_p043.shtml#summary

Orange Juice Titration Kit (1). Includes:
- Juicer for extracting juice from oranges
- Cheesecolth
- Vitamin C tablets, 250-mg
- Masking tape
- Permanent marker
- Chemical splash goggles
- 2% Lugol's iodine solution (30 mL); also available from Amazon.com
- Soluble starch (30 g)
- Small funnel (do not use for food after using it for chemistry)
- 50 mL graduated cylinder
- 500 mL graduated cylinder
- 50 mL Ehrlenmeyer flask
- 50 mL burette
- Ring stand
- Burette clamp
- Lab apron
- Eyedropper (a transfer pipette or medicine dropper would work too)
- Nitrile gloves (rubber or latex would work too)
- Measuring spoons (a balance accurate to the 0.1 gram would also work)
- 100 mL beaker
- Glass bottle, amber. Iodine is light sensitive and needs to be stored, once mixed, in an amber glass bottle or in an aluminum foil covered bottle.

You will also need to gather these items:

About 10–12 juicing oranges (or other citrus fruit)
- Ideally, you would have access to a citrus tree with ripe fruit for the duration of the project.
- The next-best option is to use a big batch of store-bought citrus fruit. Use the procedure described below to measure the vitamin C content of citrus fruit stored for various lengths of time.
- You'll get better juice yield if you buy juicing oranges, not eating oranges.
Distilled water; available in the bottled water section of most grocery stores

Do your background research so that you are knowledgeable about the terms, concepts, and questions, above.
Wear gloves, chemical safety goggles, and a lab coat or apron when using the iodine solutions in this experiment.
Dilute the Lugol's solution 1:10 in distilled water to make your iodine titration solution. (Note: if you purchased the iodine solution for starch test, you can skip this step.)
1. Pour the 30 mL Lugol's solution into the 500 mL graduated cylinder.
2. Add enough distilled water to bring the total fluid volume to 300 mL and mix.
3. Store the solution in a clean, tightly covered glass jar that is clearly labeled. Store it in a location that is protected from light.
4. Rinse and dry the 500 mL graduated cylinder.
Make a starch indicator solution.
1. This can be anywhere from 0.5 to 1.0%. The exact amount of starch is not critical.
2. For a 0.5% solution, add 1 g (which is equivalent to 1/4 teaspoon) of soluble starch to 200 mL of near-boiling distilled water.
3. Stir to dissolve, and allow to cool.
4. When cool, store the starch solution in a clean, tightly covered glass jar that is clearly labeled.
5. Rinse and dry the 500 mL graduated cylinder.
Make a fresh vitamin C standard solution (1 mg/mL). Do this on each day that you make vitamin C measurements from oranges.
1. You will use this solution to "standardize" your iodine titration solution. You will measure how much of your iodine solution it takes to oxidize a known amount of vitamin C. You can then use your iodine titration solution to determine the amount of vitamin C from test samples of juice from oranges.
2. Crush a 250-mg vitamin C tablet, and dissolve it in 100 mL of distilled water.
3. Pour into a graduated cylinder and add distilled water to bring the total volume to 250 mL.
Titrate 25 mL of vitamin C standard solution.
1. Use a clean 50 mL graduated cylinder to measure 20 mL of vitamin C standard solution.
2. Pour this into a 50 mL Ehrlenmeyer flask (the shape of this flask allows you to swirl the solution to mix it without spilling).
3. Add 10 drops of starch indicator solution.
4. Set up the 50 mL buret on the ringstand.
5. Use a funnel to carefully fill the buret with your iodine titration solution. Tip: the fluid level should not be past the graduated markings on the buret.
6. Write down the initial volume of the iodine titration solution in the buret.
7. Place the Ehrlenmeyer flask (containing the vitamin C and starch solutions) under the buret.
8. Carefully release the spring clamp of the buret to add iodine solution drop by drop.
9. Swirl the flask to mix in the iodine solution after each addition.
10. The titration is complete when the iodine creates a blue-back color in the solution that lasts for longer than 20 seconds.
11. Record the final volume of the iodine solution in the buret.
12. The difference between the initial volume and the final volume is the amount of iodine titration solution needed to oxidize the vitamin C.
13. Repeat this step three times. You should get results that agree within about 0.1 mL.
Pick (or buy) 10–12 juice oranges. You will measure the vitamin C content of two oranges on the day of picking (day 1) and on days 2, 4, 8, and 14.
Prepare fresh-squeezed orange juice samples.
1. Use a juicer to squeeze orange juice from two oranges.
2. You need 20 mL of juice per titration, and you should do at least three titrations per storage condition, for a total of 60 mL.
3. Filter the orange juice through cheesecloth to remove any pulp and seeds.
Titrating an orange juice sample is quite similar to titrating the vitamin C standard. Here are the steps:
1. Use a clean 50 mL graduated cylinder to measure 20 mL of the fresh-squeezed juice.
2. Pour this into a 50 mL Ehrlenmeyer flask (the shape of this flask allows you to swirl the solution to mix it without spilling).
3. Add 10 drops of starch indicator solution.
4. Set up the 50 mL buret on the ringstand.
5. Fill the buret nearly full with your iodine titration solution.
6. Write down the initial volume of the iodine titration solution in the buret.
7. Place the Ehrlenmeyer flask (containing the vitamin C and starch solutions) under the buret.
8. Carefully release the spring clamp of the buret to add iodine solution drop by drop.
9. Swirl the flask to mix in the iodine solution after each addition.
10. The titration is complete when the iodine creates a distinct color change in the juice/starch solution. This color change will be harder to see than with the vitamin C solution, since the juice starts out orange. The color will change from orange to grayish brown when the endpoint is reached. If you continue to add iodine, the color will darken further. You want to note the volume of iodine added when the color first changes.
11. Record the final volume of the iodine solution in the buret.
12. The difference between the initial volume and the final volume is the amount of iodine titration solution needed to oxidize the vitamin C.
13. Repeat this step three times. You should get results that agree within about 0.1 mL.
You can calculate the amount vitamin C in your samples by setting up a proportion. Here's an example (with made-up numbers) to show you how:
1. Let's say that it took 8.5 mL of iodine solution to titrate 20 mL of 1 mg/mL vitamin C standard solution, which means 20 mg vitamin C total.
2. Let's also say it takes 6.8 mL of iodine solution to titrate a 20 mL test sample of orange juice.
3. We'll call the amount of vitamin C in the orange juice sample x. You can find what x is with the following equation:
  
  X = (6.8 mg/mL) * (20 mg)/(8.5 mL) = 16.0 mg
From your results, which oranges had the most vitamin C?

Burning Calories: How Much Energy is Stored in Different Types of Food?

http://www.sciencebuddies.org/science-fair-projects/project_ideas/FoodSci_p012.shtml#procedure

Materials and Equipment

A project kit containing most of the items needed for this science project is available for puchase from AquaPhoenix Education. Alternatively, you can gather the materials yourself using this shopping list:

homemade calorimeter, (for diagram and instructions on assembling, see Experimental Procedure, below) requires:
- two tin cans, one larger than the other,
- wood dowel, pencil or other rod-shaped support,
- cork,
- needle or wire,
- hammer and nail,
graduated cylinder,
water (preferably distilled),
thermometer (calibrated in °C, range 20–100 or greater),
safety glasses,
lighter or matches,
scale (calibrated in grams, for determining energy content per gram of food), such as the Fast Weigh MS-500-BLK Digital Pocket Scale, 500 by 0.1 G, available from Amazon.com
food items to test (dry items will obviously work better), for example:

roasted cashew nuts, peanuts or other whole nuts,
pieces of popcorn,
marshmallows,
small pieces of bread,
dry pet food.

Constructing the calorimeter (refer to the diagram above).
1. Select two cans to build your calorimeter. They should nest inside one another. The smaller can needs to sit high enough so that you can place the cork, needle and food item beneath it.
2. Remove the top and bottom from a coffee (or similar-sized) can, so that you have a cylinder open on both ends.
3. Use a hammer and nail to make holes in the bottom (to allow air to in to sustain the flame).
4. Punch holes at opposite sides of the smaller can for the support to pass through. The diagram labels the support as a glass rod, but you can use a wood dowel, a pencil, or a metal rod for the support. Your support needs to be longer than the width of your large can.
5. Grasp the needle (or wire) and push its blunt end into the cork. You will impale the food to be tested on the sharp end of the needle. (If you use wire, you can wrap it around the food item to be tested. Don't use insulated wire!)
6. The smaller can will hold the water to be heated by burning the food samples. Use the graduated cylinder to measure how much water you use; the can should be about half-full. Put the supporting rod in place through the two holes.

Food Science project top down view of homemade calorimeter

Figure 2. A top down view of the homemade calorimeter is shown here.

Weigh each of the food items to be tested and record the weight.
Fill the small can about half-way with a measured amount of distilled water.
Measure the initial temperature (T_i) of the water.
Impale the food item on the needle (or wrap the wire around it).
Have your calorimeter pieces close at hand, and ready for use. For more information on how to properly weigh items see Chemistry Lab Techniques.
Place the cork on a non-flammable surface. Light the food item (the nuts may take awhile to catch fire).
When the food catches fire, immediately place the large can around the cork, then carefully place the smaller can in place above the flame.
Allow the food item to burn itself out.
Carefully remove the small can by holding the ends of the supporting rod, and place it on a flat, heat-proof surface. The can will be hot, so be careful.
Carefully stir the water and measure the final temperature (T_f). Make sure the thermometer has reached a steady level before recording the value.
When the burnt food item has cooled, carefully remove it from the needle (or wire) and weigh the remains.
Repeat steps 2–13 for all of the food items. It's a good idea to repeat the measurement with multiple samples of each food item, to insure consistent results.
Analyze your data. Calculate the energy released per individual food item (in calories and Calories), and the energy per unit weight of each food item (in calories/gram and Calories/gram). From your individual results, calculate average values for each food type.

Questions

Which food type released the most energy per gram?
Can you calculate the average energy (in Calories) for each type of food item you tested?
Do you think the amount of Calories you measured is likely to be higher or lower than the true value for each food item? Why?

Diet and Memory: Is There a Connection?

http://www.education.com/science-fair/article/diet-memory-connection/

Research Question:

Does diet have any effect on memory?

Some fruits, vegetables, grains and fish are believed to be able to improve the health of your brain. A diet that is rich in these foods may improve your ability to remember and may even protect against diseases like Alzheimer’s. In this experiment, you will evaluate whether or not a diet that is supplemented with these brain-enhancing foods can help improve memory.

Materials:

"Memory-boosting” food (e.g., cruciferous vegetables, leafy green vegetables, red/purple fruits and vegetables, onions, fish, and food rich in folic acid)
Approximately 30 test subjects
Computer
Printer
Notebook for analyzing results

Experimental Procedure:

Research food that is believed to improve memory.
Create several memory tests to give participants. Example tests include the following: Read a list of 25 items. After 10 minutes, ask participants to write down as many of these items as they can remember; Show a picture containing many items. Allow participants to study it for 1 minute. After an hour, ask test subjects to list items that they observed in the picture; Ask test subjects to describe the weather from each day over the past week.
Ask test subjects to take your memory tests. Record the results from each test.
Ask half of your test subjects to change their diet for approximately 3 weeks to include an increased amount of memory-enhancing food. Ask this group to keep a food diary so that you have an idea of how well each test subject adhered to their “new” diet. The other half of your test subjects should follow their usual diet.
After 3 weeks ask all of your test subjects to repeat the memory tests. Change each test slightly so that they are not the same as they were before. Analyze the new tests. How much of an effect (if any) does food/diet appear to have on memory? Do those who altered their diets perform better on your memory tests compared to the group that continued their normal diet?

Are Fungi Plants?

http://www.education.com/science-fair/article/are-fungi-plants/

Research Question:

How are fungi different from green plants?
What is the difference between sugar and starch?
What is a chemical indicator?
What happens when Benedict’s solution reacts with sugar?
What happens when iodine reacts with starch?

Materials:

Store-bought mushrooms
Iodine (available from drug store or scientific supply outlet)
Sugar
Measuring spoon or graduated cylinder
Benedict’s solution (available from scientific supply outlet)
Paring knife
Kitchen stove
Small saucepan for heating mushrooms
Green leaves
White sugar
Scissors

Procedure for Experiment #1

Slice the mushroom lengthwise.
Using an eyedropper place eight to ten drops of iodine on the interior surface of the mushroom.
Write down your observation. Do you think there was more starch or sugar in the mushrooms?

Procedure for Experiment #2

Put a half cup of water into a saucepan. Add one tbsp. of sugar and one tbsp of Benedict’s solution and stir.
Heat to a low simmer.
Carefully pour the hot water into a two-cup measuring cup. Did you observe any changes in color? Record your observations.

Procedure for Experiment #3

Dice four or five small mushrooms into very small pieces.
Put the mushrooms in a small saucepan. Add three-fourths cup water and 20 ml (approximately 1.5 tablespoons) Benedict’s solution to the saucepan
Bring the mushrooms to a simmer. Continue simmering for five minutes.
Turn off the stove. Decant the water into a clear glass measuring cup. Was there a color change? Write down your observations. What do you deduce from what you observed?

Procedure for Experiment #4

Repeat experiment #4, using eight to ten green leaves instead of mushrooms. The leaves should be collected first thing in the morning, and the experiment should be performed immediately thereafter. Using a scissor, cut the leaves in small pieces about a centimeter wide before covering them with water.

How Does Microwave Radiation Affect Different Organisms?

http://www.education.com/science-fair/article/microwave-radiation-affect-different-organisms/

Research Questions:

Does microwave radiation destroy all life?
Will varying lengths of radiation affect organisms differently?

Microwave ovens blast food with high levels of energy. This results in heating up certain fats and other ingredients in food. The energy simply passes through other substances without damage. Through this experiment, we will see how this energy affects simple organisms of different types.

Materials:

Packet of radish seeds
Paper towels
Four small containers filled with sterilized potting soil
Four packets of bakers’ yeast
Four small bowls
Four prepared Petri dishes with agar (available from biological supply companies)
Sterilized swabs
Gloves
Microwave
Notepad and pen
Camera

Experimental Procedure:

Plant several radish seeds in a small container. Put them in a sunny, warm location. This is the control sample.
Place several more radish seeds on a paper towel. Microwave the seeds for five seconds.
Plant these seeds in another pot and place in the same location as the control group.
Repeat Step 2 and 3 for two more samples, except microwave one group of seeds for fifteen seconds and the other for thirty seconds.
Tend the samples by watering the pots once a day and ensuring they get enough sunlight.
Take pictures everyday and note if and how quickly the samples grow.
Dump a packet of bakers’ yeast into a small bowl of warm water. Stir. This is the control sample.
Take note of how long it takes for the yeast to bubble up and how vigorous the reaction is. Take photos.
Dump another packet of bakers’ yeast onto a plate. Microwave for five seconds.
Mix this yeast into another bowl of warm water. Repeat Step 8.
Repeat steps 9 and 10 for the other packets of yeast, except microwave one sample for fifteen seconds and the other for thirty seconds.
Wearing gloves, use the sterilized swab to collect a sample of bacteria and swab it on a prepared Petri dish. Good places to find bacteria are areas where lots of people touch something, like doorknobs or faucets. Seal the dish and label it “control.” Put it in a warm, dark place. This is your control sample.
Swab another sample from the exact location as the control sample. Smear it on another Petri dish. Seal and label the dish. Place it in a warm, dark place.
Repeat Step 13 for the other two samples.
Let the samples alone overnight.
Take one sample out (not the control) and microwave it for five seconds. Place it back in the warm, dark place.
Repeat Step 16 for the other two samples, except microwave one for fifteen seconds and the other for thirty seconds.
After another day, take out all the samples. Note how many colonies of bacteria are growing and their size.
Analyze all this data. Does microwave radiation affect all life equally? Does time matter? How does each type of organism respond to the radiation?