# Is the Quantity of Capsaicin in Food Related to Its Organoleptic and Sensory Effects? A Systematic Review

## TL;DR

This paper reviews how capsaicin levels in food relate to sensory effects, finding that while quantitative methods improve accuracy, they don't consistently predict sensory outcomes.

## Contribution

The study highlights limitations in correlating measured capsaicin levels with sensory effects and suggests emerging technologies may refine current methods.

## Key findings

- Quantitative capsaicin levels correlate with extrapolated Scoville Heat Units (SHU) values.
- No direct relationship was found between capsaicin levels and consistent sensory effect measurements.
- Emerging technologies like electronic tongues and AI may improve chemesthetic profiling.

## Abstract

Capsaicin, an alkaloid predominantly found in plants in the genus Capsicum, is naturally present in food and utilized in dietary supplements and medicinal products. It interacts with cellular receptors, triggering a sensory response often perceived as pain, measurable by the Scoville Organoleptic Test. However, due to its susceptibility to biases, this test has largely been supplanted by quantitative methods for determining capsaicin content. This systematic review investigates the relationship between quantitatively measured capsaicin levels in dietary products and their sensory effects. The review protocol, registered with the Open Science Framework (OSF), involved searches in the EBSCOHost, ProQuest, and Ovid databases. Findings indicate a direct correlation between quantitatively determined capsaicin levels and extrapolated Scoville Heat Unit (SHU) values. Additionally, associations were noted between capsaicin exposure and physiological responses, as well as between capsaicin sensitivity and other chemesthetic and taste modalities. However, no direct relationship was found between quantitative capsaicin levels in dietary products and consistent, reproducible measurements of their sensory effects. This research marks a point in the discourse where quantification technology refines the traditional SHU system and underscores the need to advance quantitative detection beyond SHU.

This review examined the link between capsaicin levels and extrapolated Scoville Heat Units (SHU), noting inconsistent sensory correlations. Although precise methods like HPLC quantify capsaicin accurately, converting to SHU reduces reliability. Emerging technologies such as electronic tongues and AI may address these limitations, offering standardized chemesthetic profiling and potentially replacing the SHU scale.