Retasting in Sensory Evaluation

Even with all the promises AI brings to sensory and consumer science, our field still relies heavily on high-quality, consistent human data to drive reliable conclusions. This is what research says.

What The Research Say:

𝗣𝗿𝗼𝗱𝘂𝗰𝘁 𝗧𝘆𝗽𝗲

• 𝗔𝘃𝗼𝗶𝗱 𝗼𝗿 𝗱𝗶𝘀𝗰𝗼𝘂𝗿𝗮𝗴𝗲 𝗿𝗲𝘀𝗮𝗺𝗽𝗹𝗶𝗻𝗴 if the product causes 𝘀𝗲𝗻𝘀𝗼𝗿𝘆 𝗳𝗮𝘁𝗶𝗴𝘂𝗲 𝗼𝗿 𝗰𝗮𝗿𝗿𝘆𝗼𝘃𝗲𝗿 (e.g., spicy foods, strong-flavored products).

• 𝗘𝗻𝗰𝗼𝘂𝗿𝗮𝗴𝗲 𝗿𝗲𝘀𝗮𝗺𝗽𝗹𝗶𝗻𝗴 when important attributes only emerge or intensify after repeated intake (e.g., certain textures, flavor builds).

(𝘗𝘪𝘯𝘦𝘢𝘶, 𝘊𝘰𝘳𝘥𝘦𝘭𝘭𝘦 & 𝘚𝘤𝘩𝘭𝘪𝘤𝘩, 2009 – 𝘛𝘋𝘚 𝘮𝘦𝘵𝘩𝘰𝘥𝘰𝘭𝘰𝘨𝘺)

𝗣𝗿𝗼𝗱𝘂𝗰𝘁 𝗛𝗼𝗺𝗼𝗴𝗲𝗻𝗲𝗶𝘁𝘆

• 𝗛𝗼𝗺𝗼𝗴𝗲𝗻𝗲𝗼𝘂𝘀 𝗽𝗿𝗼𝗱𝘂𝗰𝘁𝘀 (e.g., soft drinks, smooth yogurts): One bite or sip may be sufficient; resampling may increase adaptation/fatigue. (𝘓𝘢𝘸𝘭𝘦𝘴𝘴 & 𝘏𝘦𝘺𝘮𝘢𝘯𝘯, 2010)

• 𝗛𝗲𝘁𝗲𝗿𝗼𝗴𝗲𝗻𝗲𝗼𝘂𝘀 𝗽𝗿𝗼𝗱𝘂𝗰𝘁𝘀 (e.g., granola, layered meals): A single sample may not represent the whole; multiple intakes help reduce variability. (𝘓𝘢𝘸𝘭𝘦𝘴𝘴 & 𝘏𝘦𝘺𝘮𝘢𝘯𝘯, 2010)

𝗧𝗵𝗲 𝗣𝘀𝘆𝗰𝗵𝗼𝗹𝗼𝗴𝗶𝗰𝗮𝗹 𝗟𝗮𝘆𝗲𝗿: 𝗪𝗵𝗮𝘁 𝗧𝗵𝗲𝗼𝗿𝘆 𝗧𝗲𝗹𝗹𝘀 𝗨𝘀

• Under the 𝗧𝗵𝘂𝗿𝘀𝘁𝗼𝗻𝗶𝗮𝗻 𝗳𝗿𝗮𝗺𝗲𝘄𝗼𝗿𝗸, 𝗿𝗲𝗽𝗲𝗮𝘁𝗲𝗱 𝗲𝘅𝗽𝗼𝘀𝘂𝗿𝗲 reduces the 𝘃𝗮𝗿𝗶𝗮𝗻𝗰𝗲 𝗼𝗳 𝘁𝗵𝗲 𝗱𝗶𝗳𝗳𝗲𝗿𝗲𝗻𝗰𝗲 𝗱𝗶𝘀𝘁𝗿𝗶𝗯𝘂𝘁𝗶𝗼𝗻, thereby 𝗶𝗻𝗰𝗿𝗲𝗮𝘀𝗶𝗻𝗴 𝗱𝗶𝘀𝗰𝗿𝗶𝗺𝗶𝗻𝗮𝘁𝗶𝘃𝗲 𝗽𝗼𝘄𝗲𝗿.

(𝘑𝘶𝘴𝘭𝘪𝘯 & 𝘖𝘭𝘴𝘴𝘰𝘯, 1997; 𝘙𝘰𝘶𝘴𝘴𝘦𝘢𝘶 & 𝘌𝘯𝘯𝘪𝘴, 2022)

• Experiments back this up:

Allowing retasting improved discrimination by 𝟮𝟱% 𝘁𝗼 𝟭𝟬𝟬%, even with 𝗵𝗼𝗺𝗼𝗴𝗲𝗻𝗲𝗼𝘂𝘀 𝗽𝗿𝗼𝗱𝘂𝗰𝘁𝘀 like fruit juice!

(𝘙𝘰𝘶𝘴𝘴𝘦𝘢𝘶 & 𝘖’𝘔𝘢𝘩𝘰𝘯𝘺, 2000; 𝘐𝘴𝘩𝘪𝘪 𝘦𝘵 𝘢𝘭., 2014)

𝗞𝗲𝘆 𝗧𝗮𝗸𝗲𝗮𝘄𝗮𝘆

Providing 𝗰𝗹𝗲𝗮𝗿 𝗮𝗻𝗱 𝗰𝗼𝗻𝘀𝗶𝘀𝘁𝗲𝗻𝘁 𝗿𝗲𝘀𝗮𝗺𝗽𝗹𝗶𝗻𝗴 𝗶𝗻𝘀𝘁𝗿𝘂𝗰𝘁𝗶𝗼𝗻𝘀 to panelists is critical. Without this, decisions based on sensory data can vary drastically—just due to a change in how the test was run.

𝗥𝗲𝗳𝗲𝗿𝗲𝗻𝗰𝗲𝘀

• Lawless & Heymann (2010). Sensory Evaluation of Food (2nd ed.). Springer

• Pineau, Cordelle, & Schlich (2009). Temporal Dominance of Sensations: What is a good attribute list? FQP, 20

• Juslin & Olsson (1997). Thurstonian and Brunswikian origins of uncertainty in judgment. Psych. Rev., 104

• Rousseau & Ennis (2022). How retasting can improve the power of product testing. In Tools and Apps. IFPress

• Rousseau & O'Mahony (2000). Effect of within-trial retasting on discrimination tests. FQP, 11

• Ishii, O'Mahony & Rousseau (2014). Small sensory differences, resampling, and consumer relevance. FQP, 31