# Matrix‐Dependent Sweet–Sour Psychophysics: gLMS and Time‐Intensity of Sugar Alcohol‐Acid Mixture in Liquids and Tablets

## TL;DR

This study explores how sweet and sour tastes interact in different food formats, helping to design better low-sugar products.

## Contribution

The work introduces matrix-specific psychophysical models for sweet-sour interactions in liquids and tablets.

## Key findings

- Tablets showed steeper sourness growth than liquids with higher acid exponents.
- Malic acid produced steeper sourness growth than citric acid in most cases.
- Time-intensity parameters can control sweetness-sourness balance predictably.

## Abstract

Precision control of sweet–sour interactions is pivotal for reduced‐sugar design across formats. This work quantified psychophysical functions for xylitol, erythritol, and sorbitol with citric or malic acid in liquids and tablet candies using gLMS concentration‐intensity and time‐intensity methods. In liquids, subthreshold ratings clustered near barely detectable, while suprathreshold relations followed Stevens' power law; exponents declined at extreme levels, indicating saturation. Tablets preserved power‐law scaling yet exhibited > 79% higher acid exponents than liquids, producing steeper sourness growth; in erythritol and sorbitol, malic exceeded citric by > 21%, whereas exponents were ~1 and comparable in xylitol. TI results showed bidirectional suppression: acids lowered sweetness (I
max, AUC), with xylitol displaying compressed onset‐decay‐persistence; sugar alcohols attenuated sourness, with malic less inhibited than citric. These parameters enable predictable, matrix‐specific tuning to preserve sweetness, prevent sourness spikes, and support evidence‐based formulation for consumer acceptance, regulatory sugar targets, shelf‐life stability, and scalability.

Tablets showed > 79% steeper sourness growth than liquids by power law. Malic acid yielded steeper sourness growth than citric acid in most matrices and xylitol matrix yielded balanced perception with near‐unity sourness exponents. Time‐intensity parameters provide actionable targets for controlling sweetness‐sourness balance.