Assessing the hidden risks of non‐thermal processing: Ultrasound‐induced toxicity of cashew apple juice in a zebrafish model

BACKGROUND: High-intensity ultrasound is widely advocated for the preservation of liquid foods; however, the potential formation or release of toxic compounds during processing remains under-investigated. This study evaluated the toxicological profile of cashew apple juice processed by high-intensity ultrasound (1250, 1875, and 2500 W;L⁻¹) using two biological models of differing complexity: brine shrimp (Artemia salina) and zebrafish (Danio rerio). RESULTS: Neither unprocessed nor sonicated juice exhibited acute toxicity in A. salina nauplii. In contrast, D. rerio assays revealed significant, parameter-dependent developmental toxicity in sonicated samples, whereas unprocessed juice proved biocompatible. Sonication induced severe morphological anomalies in zebrafish, including cardiac edema, spinal curvature, and growth retardation. Toxicity was inversely related to treatment duration; short processing times (5 min) induced higher mortality and morbidity than longer durations (15 min), suggesting the degradation of toxic compounds during extended processing. CONCLUSION: These findings demonstrate that D. rerio is a more sensitive model than A. salina for assessing the safety of non-thermally processed foods in the tested conditions. Although ultrasound is effective, processing parameters can critically alter the toxicological profile of the food matrix, highlighting the need for comprehensive safety evaluations using sensitive vertebrate models prior to industrial application.