Jump to main content

Flavor That Food! Exploring the Science of Marinades

150 reviews


Have you ever tasted a delicious burger and wondered how it got so much flavor? Maybe you have heard your family talk about marinating foods before cooking or grilling them. A marinade is a mixture of seasonings used to flavor or tenderize food. Most cooks have strong opinions about the best way to marinate their favorite food, be it a large steak or a tofu burger. In this cooking and food science fair project, you will run controlled tests to see what factors are most important in making a marinade ingredient stick to the surface of food. Get ready to maximize your marinade!


Areas of Science
Time Required
Short (2-5 days)
Material Availability
Readily available
Low ($20 - $50)
Adult supervision is required. Use caution and ask an adult to help you use the knife.

David Whyte, PhD, and Teisha Rowland, PhD, Science Buddies


Determine how various ingredients affect the adsorption of a marinade onto food.


Every culture has its own unique way of preparing food. But whether it is Chinese or American, Italian or Indian, some of the main dishes call for a marinade. The word marinade comes from the Latin word marinara, which means "of the sea." The original marinades from several centuries ago were briny (very salty) liquids, like seawater. Whatever they are made of, marinades are meant to preserve, tenderize, and flavor foods. Figure 1, below, shows raw chicken thighs soaking in a teriyaki-flavored marinade.

Raw chicken thighs are partially submerged in a liquid marinade
Figure 1. This is a picture of raw chicken thighs being soaked in a teriyaki-flavored marinade. (Image credit: Gran / Wikimedia Commons)

In this science fair project, you will test how various ingredients affect the adsorption (yes, with a "d") of a marinade ingredient onto the surface of a food. The word adsorb is used to describe the process by which a substance adheres to the surface of an object, as opposed to being absorbed into it. The ingredients you will be testing are salt, vinegar, and sugar. Salt can help a marinade break open animal cells, which make up a piece of meat. Salt also obviously makes foods salty, while sugar makes them sweet. But how well do these ingredients work for making a marinade be adsorbed to food? Vinegar is an acid — other acids you might find around the kitchen include lemon juice and orange juice. Acids can cause foods, like meats, to be broken down, or tenderized. Does this help make vinegar a good marinade?

While you will be testing salt, vinegar, and sugar as your key marinade ingredients, you will not be using actual seasoned marinades. Instead, along with these ingredients you will use a food dye to determine the level of adsorption because a food dye is easy to measure visually. The food you will use for the experiments is tofu, which has the benefits of being inexpensive and easy to cut into cubes. Using tofu and food dyes might seem like an odd way to study marinades, but using a real marinade and steaks would be quite costly and difficult to visually examine. This is a good example of simplifying a complex problem to make it easier to control the variables so you get a clear result.

The methods might be unusual, but the results of your experiments can be applied in the kitchen the next time you help your family prepare your favorite marinade!

Terms and Concepts



Materials and Equipment

Experimental Procedure

Preparing Your Materials

To start this science fair project, you should assemble all of the materials on a clean workspace.

  1. Have your adult helper cut the tofu block into cubes, about 2 centimeters (cm) on each side, as shown in Figure 2, below. Cut about 60 tofu cubes. Keep the unused tofu in case you need more cubes.
Tofu is cut into eighteen uniform cubes and placed on a plate
Figure 2. Cut the tofu into cubes like the ones shown here. (Note that this picture shows 18 cubes, but you will want to make about 60.)
  1. Store 40 of the tofu cubes under plastic wrap in the refrigerator so they do not dry out.
  2. The first 20 tofu cubes should be brought to room temperature for the first trial.

Creating Your Standards

In this section, you will make a set of standards. These will be used to compare the tofu cubes from your test solutions to so you can see which test solution helps the food product adsorb more marinade. The standards will progress from "1" for no color, up to "6" for the maximum amount of color.

  1. Using the permanent marker, label six of the plastic cups with the numbers 1-6. Line them up on your workspace in increasing order.
  2. Put ½ cup (C) of water into each of the six cups.
  3. Add dye to the cups, starting with the cup labeled "1," as follows: 0 drops, 1 drop, 2 drops, 4 drops, 8 drops, and 16 drops.
  4. Stir the dye in each cup, going from the cup labeled "2" to the cup labeled "6." Your cups should now look like the ones in Figure 3, below.
Six clear plastic cups with different concentrations of a blue dye
Figure 3. Once you have mixed the dye in your standard solutions, they should look like the ones shown here.

Preparing the Test Solutions

Now it is time to make the test solutions. Make sure you rinse out the measuring cup and measuring spoon between making each solution.

  1. Label four plastic cups, as follows: water, salt, vinegar and sugar.
  2. To the "water" cup, add 1 C of water.
  3. To the "salt" cup, add 1 tablespoon (tbsp.) of salt and 1 C of water.
    1. Since 1 tbsp. of salt is about 18 grams (g), and 1 C of water is about 230 g, this is roughly an 8 percent solution of salt.
  4. To the "vinegar" cup, add ¼ C of vinegar and ¾ C of water.
    1. Look at the label on the vinegar bottle for the percent acidity. The percent acidity measures the percent of acetic acid in the vinegar. Divide this number by 4 to obtain the percent acidity for your test solution. Record this information in your lab notebook.
  5. To the "sugar" cup, add 1 tbsp. of sugar and 1 C of water.
    1. Since 1 tbsp. of sugar weighs about 14 g, and 1 C of water weighs about 230 g, this is roughly a 6 percent solution of sugar.
  6. Add eight drops of dye to each of the solutions: water, salt, vinegar, and sugar.
  7. Using a clean spoon or other utensil for each of the four cups, stir the cups so that the dye gets mixed in and the salt and sugar are completely dissolved in their cups. Your cups should now look like the ones in Figure 4, below.
Four plastic cups are filled with a dark blue solution and are labeled water, salt, vinegar and sugar
Figure 4. Your prepared test solutions should look like the ones in this picture.

Testing the Solutions

  1. Carefully add two room-temperature tofu cubes to each of the solutions you prepared (the six standard solutions and the four test solutions). Do not worry if the cubes in the salt solution float.
  2. Record the times that the cubes go into and come out of the dye test solution in your lab notebook.
  3. Allow the tofu cubes to marinate for 1 hour at room temperature.

Analyzing the Tofu Cubes

  1. Prepare a surface, with appropriate labels, on which to put the tofu cubes, as shown in Figure 5, below. Position the white sheet of paper lengthwise. On the piece of paper, write the following with the permanent marker:
    1. The numbers 1 to 6, about 5 cm apart near the top of the paper. The cubes from the standards will go right below these numbers.
    2. The words water, salt, vinegar, and sugar across the middle of the paper. Write the words about 5 cm apart. The cubes from the test solutions will go right below these words.
Numbers one through six are written on a piece of paper with the words water, salt, vinegar and sugar below it
Figure 5. Prepare a sheet of paper like this one for you to put your tofu cubes on (directly below the labels) and compare the cubes from the test solutions with the ones from the standards.
  1. Cover the paper with clear plastic wrap. You will put the cubes on the plastic wrap (directly below the words that describe their treatment) to keep food dye from leaking onto the paper. Work on a surface that can get a little wet.
  2. Using a slotted spoon, remove the two cubes from each of the standard solutions.
  3. Line the cubes up on the piece of plastic wrap, with the two cubes next to each other, just below their corresponding numbers, 1 to 6. This is your set of standards.
  4. Using the same slotted spoon, remove the two cubes from each of the test solutions.
  5. Put the cubes from each solution just below the word that indicates its solution: water, salt, vinegar, or sugar.
    1. Note: If not all of the surfaces on a cube are equally dyed, arrange the cube so that one of its averagely-dyed sides is facing up for you to examine and compare to the other cubes.
  6. Now estimate the level of color for the cubes from the different test solutions, using the standard cubes for comparison.
    1. Look carefully at the colors of the cubes from the water, salt, vinegar, and sugar solutions. Select which of the standard tofu cubes has a color that is the best match for each treatment. For instance, the tofu cubes from the sugar solution might most closely match the tofu cubes labeled "4."
  7. In your lab notebook, make a data table like Table 1, below. Record the test solution tofu cube and standard tofu cube matches in your data table, in the column labeled "Standard Match."
    1. If any of them are darker than standard number 6, mark it as >6.
Test Solution Standard Match
(1, 2, 3, 4, 5, or 6)
Average Standard Match
(1, 2, 3, 4, 5, or 6)
Table 1. In your lab notebook, make a data table like this one to record your results in. In the "Standard Match" column, there is a row for each tofu cube from the test solutions.
  1. Calculate the average standard match for the tofu cubes from each test solution. Record the averages in your data table, in the column labeled "Average Standard Match," for each test solution.
    1. For example, if both tofu cubes from the sugar solution matched the cubes from standard solution 4, then the average standard match for the sugar solution will be a 4.
    2. On the other hand, if one of the tofu cubes from the sugar solution matched the cubes from standard solution 4, and the other tofu cube from the sugar solution matched the cubes from standard solution 3, then the average standard match for the sugar solution will be 3.5
      (since 3 + 4 = 7, and 7 ÷ 2 = 3.5).
  2. Make a bar graph of your results. Put the test solution name on the x-axis (the horizontal axis) and the average standard match numbers on the y-axis (the vertical axis). Make a bar for each test solution.
  3. Analyze your results. What was the effect of salt on the adsorption of dye? What about vinegar and sugar?
  4. Clean all of your equipment and repeat the entire experiment two more times.
    1. Repeating an experiment helps you make sure that your results are real and accurate.
  5. Review all of your data to determine which test solution leads to the most marinade adsorption.
    1. Overall, which tofu cubes consistently adsorbed the most dye? Which adsorbed the least?
    2. What does this tell you about how well the different ingredients (sugar, salt, and vinegar) stick to the surface of food? Can you explain your results?
      1. Hint: You may want to re-read the Introduction in the Background section and do some more research on your own to find out how the different ingredients may be working to marinade food.
icon scientific method

Ask an Expert

Do you have specific questions about your science project? Our team of volunteer scientists can help. Our Experts won't do the work for you, but they will make suggestions, offer guidance, and help you troubleshoot.


  • Try variations that change one of the following: time that cubes are marinated, salt concentration, temperature (room temperature vs. refrigerator), and vinegar concentration. Vary one variable at a time, keeping everything else constant. Make fresh standard cubes if they are drying out or fading.
  • Some marinades have vegetable or olive oil in them. What happens if you mix oil in with the marinade?
  • Try natural colorings, such as saffron or paprika.
  • Experiment with a yogurt- or buttermilk-based marinade. How do these dairy products affect the marinade?
  • Vinegar is an acid. You could try this science project again using other acids that you typically have in the kitchen, such as lemon juice or orange juice. How well do these other acids that you use as food marinate the tofu cubes compared to the vinegar? To find out more about which foods are acidic, check out the Science Buddies' resource Acids, Bases, & the pH Scale.
  • Cut the tofu cubes with a knife after adsorption to investigate how far the dye has been absorbed into the cubes.
  • Experiment with cubes of chicken breast or other meat. Caution: Raw chicken might have live Salmonella bacteria, which is a health hazard. Be careful to wash everything that comes into contact with the raw meat.


If you like this project, you might enjoy exploring these related careers:

Career Profile
There is a fraction of the world's population that doesn't have enough to eat or doesn't have access to food that is nutritionally rich. Food scientists or technologists work to find new sources of food that have the right nutrition levels and that are safe for human consumption. In fact, our nation's food supply depends on food scientists and technologists that test and develop foods that meet and exceed government food safety standards. If you are interested in combining biology, chemistry,… Read more
Career Profile
Good taste, texture, quality, and safety are all very important in the food industry. Food science technicians test and catalog the physical and chemical properties of food to help ensure these aspects. Read more
Career Profile
Everything in the environment, whether naturally occurring or of human design, is composed of chemicals. Chemists search for and use new knowledge about chemicals to develop new processes or products. Read more
Career Profile
The role that the chemical technician plays is the backbone of every chemical, semiconductor, and pharmaceutical manufacturing operation. Chemical technicians conduct experiments, record data, and help to implement new processes and procedures in the laboratory. If you enjoy hands-on work, then you might be interested in the career of a chemical technician. Read more

News Feed on This Topic

, ,

Cite This Page

General citation information is provided here. Be sure to check the formatting, including capitalization, for the method you are using and update your citation, as needed.

MLA Style

Science Buddies Staff. "Flavor That Food! Exploring the Science of Marinades." Science Buddies, 20 Nov. 2020, https://www.sciencebuddies.org/science-fair-projects/project-ideas/FoodSci_p043/cooking-food-science/science-of-marinades?from=Blog. Accessed 20 Feb. 2024.

APA Style

Science Buddies Staff. (2020, November 20). Flavor That Food! Exploring the Science of Marinades. Retrieved from https://www.sciencebuddies.org/science-fair-projects/project-ideas/FoodSci_p043/cooking-food-science/science-of-marinades?from=Blog

Last edit date: 2020-11-20
Free science fair projects.