Apple Browning Lab Guide
5th Grade Science Fair
Apple Browning Lab Guide
Name: ___________________________
Date: ____________________________
Testable Science Fair Question
"Which household liquid treatment—lemon juice, salt water, honey water, or milk—prevents sliced apples from browning the longest?"
Why this works for 5th grade: It compares clear, safe household liquids, uses an easy-to-measure outcome (browning over time), and includes a fair-test control.
More 5th Grade Questions About Preventing Apple Browning:
- Acidic Liquids: "Which acidic liquid—lemon juice, lime juice, orange juice, or white vinegar—keeps apple slices freshest?"
- Kitchen Solutions: "Does salt water, sugar water, or baking soda water prevent apple browning best?"
- Citrus vs. Soda: "Which drink—lemon juice, ginger ale, or sparkling water—stops apple slices from turning brown the longest?"
- Apple Varieties: "Does lemon juice prevent browning equally well on Granny Smith, Honeycrisp, and Red Delicious apples?"
Identify Your Variables
Independent Variable
(What you change)
The type of liquid treatment coated on each apple slice.
Dependent Variable
(What you measure)
The amount of browning on each slice over 2 hours (1–5 scale).
Controlled Variables
(What stays the same)
Same apple, slice thickness, amount of liquid, plate, and room temperature.
Write Your Hypothesis
Use an If... then... because... statement to predict which treatment will work best.
If I coat apple slices in
,
then it will prevent browning the best
because
Experiment Plan & Observation Log
Fair Test Data
Materials Needed
- ☐ 1 large apple (cut into 5 equal slices)
- ☐ 2 tbsp lemon juice
- ☐ 2 tbsp salt water (1/2 tsp salt in 1 cup water)
- ☐ 2 tbsp honey water (1 tsp honey in 1 cup water)
- ☐ 2 tbsp milk
- ☐ 5 labeled paper plates & a timer
Fair-Test Steps
- Label 5 plates: Control (Nothing), Lemon Juice, Salt Water, Honey Water, and Milk.
- Brush or dip each slice in its matching liquid for 10 seconds, then place it flat on its plate. Leave the Control slice dry.
- Start your timer! Rate each slice's browning at 0, 15, 30, 60, and 120 minutes using the scale below.
Browning Rating Scale (1 = Fresh, 5 = Very Brown)
1
Crisp white, no brown
2
Tiny brown spots
3
Lightly brown edges
4
Mostly brown
5
Dark brown all over
Browning Observation Table (Record Rating 1–5)
| Treatment |
0 min |
15 min |
30 min |
60 min |
120 min |
| Control (No Liquid) |
|
|
|
|
|
| Lemon Juice |
|
|
|
|
|
| Salt Water |
|
|
|
|
|
| Honey Water |
|
|
|
|
|
| Milk |
|
|
|
|
|
Extra Observations (Smell, Texture, or Surprises)
Analysis & Conclusion Questions
Use Your Data
1. Which treatment prevented browning the best after 120 minutes, and how do you know?
Cite specific ratings from your Browning Observation Table as evidence.
2. How did the Control slice (no liquid) compare to the treated slices?
Why is it important to include a control slice in a science fair experiment?
3. Did your results support your hypothesis? Explain why or why not.
4. Why do you think the winning treatment worked best, and what would you test next?
Think about acidity, coating thickness, or trying different types of apples.
