Abstract

Acrylamide formation in starchy foods during high-temperature processing, has remained a pressing food safety concern. Despite numerous physical, chemical and biochemical interventions proposed at curbing its presence, quest for a sustainable solution continues. Among these approaches, L-asparaginases (EC 3.5.1.1) have emerged as a potent acrylamide mitigator in food industry. However, currently available formulations are predominantly mesophilic L-asparaginase II enzymes, which necessitate added pre-processing steps and strict temperature control, thereby limiting their industrial suitability under frying conditions. However, reports on the use of thermostable Type-I L-asparaginases for acrylamide mitigation remain scarce. To address this gap, present study evaluated a thermostable, L-glutaminase free L-asparaginase I (AfASNase), cloned from Anoxybacillus Flavithermus. This enzyme exhibited robust catalytic activity across a wide temperature (50-70°C) and pH range (5-10), showing its suitability for the process-flexible commercial food applications. Pre-treatment of sliced potatoes with three doses of AfASNase (5, 10 and 20 U.mL−1) prior to frying, clearly resulted in the dose dependent reduction of acrylamide content, achieving reduction to ~45.47% ~52.47% and ~68.96% respectively, as quantified by high performance liquid chromatography (HPLC). Notably, a synergistic pre-treatment strategy, combining blanching followed by AfASNase (20 U.mL−1) application, further slashed the acrylamide content to ~89.41%. Importantly, these substantial reductions were achieved by preserving visual golden hue and crisp in the final product, which is the key consumer preference. Collectively, these findings position AfASNase as an industrially attractive acrylamide mitigator, offering a safer and process-flexible alternative to the existing conventional mesophilic biocatalysts for lowering acrylamide content in fried foods.