Robert Gardner - Ace Your Food Science Project

HUNGRY FOR SCIENCE?

What makes up the food you eat? How can you test for carbohydrates and vitamin C? How much gas is in a bottle of soda? The fun biology and chemistry experiments in this book allow young scientists to follow the scientific method. Many experiments include ideas they can use for a science fair project.

About the Authors

ROBERT GARDNER is an award-winning author of science books for young people. He is a retired high school teacher of physics, chemistry, and physical science. After teaching science for nearly thirty years, SALVATORE TOCCI decided to devote his time to writing chemistry textbooks and science books for young readers. THOMAS R. RYBOLT has taught chemistry at the University of Tennessee at Chattanooga for more than twenty-five years.

When you hear the word science, do you think of a person in a white lab coat surrounded by beakers of bubbling liquids, specialized lab equipment, and computers? What exactly is science? Maybe you think science is only a subject you learn in school. Science is much more than that.

Science is the study of the things that are all around you, every day. No matter where you are or what you are doing, scientific principles are at work. You dont need special materials or equipment, or even a white lab coat, to be a scientist. Materials commonly found in your home, at school, or at a local store will allow you to become a scientist and pursue an area of interest. By making careful observations and asking questions about how things work, you can begin to design experiments to investigate a variety of questions. You can do science. You probably already have but just didnt know it!

Perhaps you are reading this book because you are looking for an idea for a science fair project for school, or maybe you are just hoping to find something fun to do on a rainy day. This book will provide an opportunity for you to learn more about food and the field of food science. You may not realize that food is a science. You probably dont think too much about the food you eat. You probably dont often consider where it came from, how it was produced, what it is made of, or how much energy it contains. Food science is an important field that covers all aspects of harvesting, handling, processing, distributing, marketing, and consuming food. This field integrates and applies knowledge from chemistry, biology, microbiology, biochemistry, engineering, and nutrition for the production of safe, wholesome, and affordable food.

From the experiments in this book, you will discover the science behind many of the foods you eat every day. You may be surprised that you can have fun and learn about food science at the same time.

All scientists look at the world and try to understand how things work. They make careful observations and conduct research about a question. Different areas of science use different approaches. Depending on the phenomenon being investigated, one method is likely to be more appropriate than another. Designing a new medication for heart disease, studying the spread of an invasive plant species such as purple loosestrife, and finding evidence about whether there was once water on Mars all require different methods.

Despite the differences, however, all scientists use a similar general approach to do experiments. It is called the scientific method. In most experiments, some or all of the following steps are used: making an observation, formulating a question, making a hypothesis (an answer to the question) and prediction (an if-then statement), designing and conducting an experiment, analyzing results and drawing conclusions, and accepting or rejecting the hypothesis. Scientists then share their findings with others by writing articles that are published in journals. Afterand only aftera hypothesis has repeatedly been supported by experiments can it be considered a theory.

You might be wondering how to get an experiment started. When you observe something in the world, you may become curious and think of a question. Your question can be answered by a well-designed investigation. Your question may also arise from an earlier experiment or from background reading. Once you have a question, you should make a hypothesis. Your hypothesis is a possible answer to the question (what you think will happen). Once you have a hypothesis, it is time to design an experiment.

In some cases, it is appropriate to do a controlled experiment. That means there are two groups treated exactly the same except for the single factor that you are testing. Any factor that can affect the outcome of an experiment is a variable. For example, if you want to investigate whether raisins will rise to the surface when placed in a carbonated beverage, two groups may be used. One group is called the control group, and the other is called the experimental group. The two groups should be treated exactly the same: The same number of raisins should be placed in the same amount of liquid, be kept at the same temperature, and so forth. The control group will be the raisins placed in sugar water, while the experimental group will be the raisins placed in ginger ale. The variable of interest is carbonation. It is the variable that changes, and it is the only difference between the two groups.

During the experiment, you will collect data. For example, you might count the number of raisins that rise to the surface. You might time how long it takes for the raisins to rise. By comparing the data collected from the control group with the data collected from the experimental group, you can draw conclusions. Because the two groups were treated exactly alike, all the raisins in the ginger ale rising to the surface would allow you to conclude with confidence that it is a result of the one thing that was different: carbonation.

Two other terms that are often used in scientific experiments are dependent and independent variables. The dependent variable here is the rising of raisins, because it is the one you measure as an outcome. Carbonation is the independent variable; it is the one the experimenter intentionally changes. After the data is collected, it is analyzed to see whether the hypothesis was supported or rejected. Often, the results of one experiment will lead you to a related question, or they may send you off in a different direction. Whatever the results, there is something to be learned from all scientific experiments.

Many of the experiments in this book may be appropriate for science fair projects. Experiments marked with a symbol () include a section called Science Fair Project Ideas. The ideas in this section will provide suggestions to help you develop your own original science fair project. However, judges at such fairs do not reward projects or experiments that are simply copied from a book. For example, a picture of the food pyramid, which is commonly found at these fairs, would probably not impress judges unless it was done in a novel or creative way. On the other hand, a carefully performed experiment to determine the amount of energy in a variety of snack foods would be likely to receive careful consideration.

Science fair judges tend to reward creative thought and imagination. However, its difficult to be creative or imaginative unless you are really interested in your project. Take the time to choose a topic that appeals to you. Consider, too, your own ability and the cost of materials. Dont pursue a project that you cant afford.

If you decide to use a project found in this book for a science fair, you will need to find ways to modify or extend it. This should not be difficult because you will probably find that as you do these projects new ideas for experiments will come to mind. These new experiments could make excellent science fair projects, particularly because they spring from your own mind and are interesting to you.