Triangle tests and sensory statistics

Triangle Tests

• Definition: A sensory test where tasters receive three cups—two identical, one different.
• Purpose: Determine whether tasters can reliably detect differences between coffees (e.g., different roasts, processing methods, or brew water).
• Procedure:

1. Present samples in randomized order.
2. Ask tasters to identify the odd cup.
3. Record results and analyze statistically.

Sensory Statistics

• Chance Probability: Random guessing gives ~33% correct responses.
• Significance Testing: Use binomial probability to assess if correct identifications exceed chance.
• Example: With 10 tasters, at least 7 correct is statistically significant at p<0.05.
• Applications:
• Validating whether small roast changes are perceptible.
• Testing water chemistry adjustments.
• Assessing packaging or storage impact.

Best Practices

• Use blinded, randomized samples.
• Standardize brew method, ratio, and temperature.
• Use multiple sessions and tasters for reliable data.

Summary

Triangle tests, supported by sensory statistics, provide a rigorous way to determine whether perceived differences between coffee samples are real or due to chance, strengthening quality control decisions.

• Tags:
• Best Practices
• Quality Control
• Water Chemistry
• Brew Method
• Processing Methods