Different extrusion conditions tailor polyphenol profile and bioaccessibility in black rice-based pasta: A...

Extrusion temperature can modulate the stability and bioaccessibility of phenolics in black rice pasta. Pasta was produced under cold (30-40 °C) and thermal (60-80 °C) extrusion conditions and evaluated after extrusion, drying, cooking and in vitro digestion. Free and bound phenolics were profiled by UHPLC-HRMS untargeted metabolomics and semi-quantified by subclass. Multivariate modeling (HCA/PCA; AMOPLS) identified the in vitro digestion as the dominant driver (RSS >68%), whereas extrusion temperatures marginally contributed (<10%). Cold extrusion preserved higher initial anthocyanins and phenolic acids, while thermal extrusion shifted the fingerprint toward lower-molecular-weight phenolic acids. Following in vitro digestion, samples from both extrusion conditions converged toward similar bioaccessible phenolic patterns, with flavanols markedly increasing, indicating a release from bound pools. Overall, extrusion chiefly governs phenolic form more than final bioaccessible diversity, providing a lever to tailor functional rice pasta. Findings support novel process optimization for phenolic-rich, black rice pasta formulations.