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Bob Pellegrino

@kingfunk.bsky.social

130 followers 152 following 26 posts

Assistant Professor at Texas A&M University Human psychophysicist interested in all things smell and texture. 📸: @smellboi24_7

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Bob Pellegrino @kingfunk.bsky.social · 16/01/2026

2/3 We’ve built and tested an odor sampling bag system with: - Known concentrations - Closed headspace - Air as the carrier (no solvent confounds) In head-to-head tests, bags produced more reliable results than jars and preserved odorant-specific differences.

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Bob Pellegrino @kingfunk.bsky.social · 12/08/2025

This isn’t just theory! These models can replace slow, expensive “omission tests” in flavor chemistry to find the handful of molecules that actually matter in a food’s aroma. For instance, what molecules really make coffee smell like coffee. ☕

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Bob Pellegrino @kingfunk.bsky.social · 12/08/2025

4/5 Using this information, we can predict perceived odor intensity from molecular structure + concentration with high accuracy for both: • Single molecules (RMSE = 7.1 on a 100 point scale) • Complex mixtures (RMSE ~ 7.5)

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Bob Pellegrino @kingfunk.bsky.social · 12/08/2025

3/5 Using a very cool bag system to tightly control the concentration, we measured: • 62 molecules, each at ≥7 concentrations • 260 mixtures (2–10 components) • >7,000 intensity ratings from trained human panels

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Bob Pellegrino @kingfunk.bsky.social · 12/08/2025

2/5 It’s a trick question. At a lower concentration, acetophenone (left molecule, red, smells like urinal cake) is stronger than 2-heptanone (right molecule, green, smells like blue cheese). So concentration ≠ intensity. That’s been a major roadblock for neuroscience and fragrance / food industries

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Bob Pellegrino @kingfunk.bsky.social · 12/08/2025

1/5 Odor intensity isn’t just about concentration! We have a new preprint to prove it: www.biorxiv.org/content/10.1... In cahoots with @jmainland.bsky.social, @alexkoulakov.bsky.social, Rick Gerkin, Khristina Samoilova and others not on bluesky. 🧪 Which of these molecules smells stronger?

Chemical structure of acetophenone and 2-heptanone

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