Have you ever wondered why apples get brown after you slice them? In this article, we will find out using a method that scientists use in their experiments. It’s called the scientific method — a systematic approach that allows us to investigate and comprehend the natural world. Let’s follow the method step by step.

Step 1: Observation

The first step in the scientific method is observation. By carefully examining sliced apples, we notice a rapid transformation as they turn brown shortly after exposure to air. This observation serves as the foundation of our scientific inquiry.

Step 2: Question

Based on our observation, we generate a fundamental question: What causes apples to turn brown when cut open? This question leads us to form hypotheses to explain the phenomenon.

Step 3: Hypothesis

Hypotheses are educated guesses and proposed explanations rooted in existing knowledge. In the case of apple browning, we may hypothesize that the enzymatic activity within the apple plays a significant role in this process.

Step 4: Experiment

To test our hypotheses, we design a simple experiment. We slice apples and divide them into two groups (group 1 and group 2). Group 1 slices are soaked in lime juice (an acid) for 5 minutes, drained, and the slices placed on a kitchen countertop where it is exposed to air for 30 minutes. Group 2 slices are placed on the same countertop without any application of lime juice.

Step 5: Collecting and Analyzing Data

Collecting and analyzing data is a crucial step in the scientific method. We meticulously analyze the results of our experiments, paying close attention to the extent of browning in each set of apple slices. We notice that group 1 slices retained their natural color, but group 2 slices turned brown. This observation guides us toward drawing a valid conclusion.

Step 6: Forming a Conclusion

Our findings indicate that browning is reduced when the apple slices are exposed to lime juice. We can therefore conclude that lime juice treatment interferes with enzymatic activity, preventing browning. The enzyme responsible for enzymatic browning is polyphenol oxidase. After slicing, the enzymes are exposed to oxygen, causing the production of a brown compound called melanin. Exposure to acids such as lime juice deactivates or reduces the activity of the enzyme reducing the amount of melanin formed. Understanding the mechanisms behind apple browning helps food scientists and producers to develop preservation techniques that inhibit enzymatic browning and improve the visual appeal of fresh produce.

Step 7: Sharing Your Findings

The final step of the scientific method is sharing your findings. Always remember that scientists build on the shoulders of other scientists. There is no need to reinvent the wheel if someone else has already done the work. Share your findings even if the data did not satisfy your original hypothesis. You may do this by publishing in a journal, magazine, or blog, speaking at a scientific conference, or sharing the information with a group at your school, company, or community group.

Through the lens of enzymatic browning, we have ventured into the intriguing realm of the scientific method. By keenly observing, asking questions, formulating hypotheses, conducting experiments, and analyzing data, we can arrive at valid and objective conclusions. The scientific method is a powerful tool that enables us to unlock the mysteries of the world around us. So, embrace your curiosity, ask questions, and embark on your own scientific explorations!


  • Courtney Simons

    Dr. Courtney Simons has served as a food science researcher and educator for over a decade. He holds a Bachelor of Science in Food Science and a Ph.D. in Cereal Science from North Dakota State University.