Reduction of Asparagine and Reducing Sugar Content, and Utilization of Alternative Food Processing Strategies in Mitigating Acrylamide Formation—A Review

Abstract

Acrylamide formation in carbohydrate- and protein-rich foods processed at high temperatures tends to form toxic and carcinogenic acrylamide, which has become a global challenge for sustaining food safety. The main acrylamide formation pathway is the Maillard reaction between reducing sugars (RS) and the amino acid asparagine at temperatures above 120 °C. Controlling the acrylamide content within the benchmark levels set by globally recognized food safety authorities has been critical in mass-scale food production. This paper reviews the importance of measures to reduce the two main acrylamide precursors of asparagine and RS contents at agronomical and pre-treatment stages before heat processing and alternative heat processing strategies to mitigate acrylamide formation. Cultivars with lower levels of asparagine and RS and appropriate nitrogen and sulfur fertilization have been successful in acrylamide mitigation. Pre-treatment, such as soaking, blanching, and treatment with pulsed electric fields and high-power ultrasonic liquid-solid extraction, facilitates the mass transfer of precursors to the surrounding media. L-asparaginase is important in converting asparagine into aspartic acid and ammonia, which do not participate in acrylamide formation. High hydrostatic pressure treatment has also successfully reduced acrylamide precursor content from raw materials. Introducing a fermentation step with food-related lactic acid bacteria, which rapidly utilizes asparagine and sugars as energy sources, has been effective in reducing acrylamide formation. Vacuum baking and frying and radio frequency treatment for post-baking and microwave processing have been found effective as alternative heat processing strategies. However, the key to significant acrylamide reduction lies in the accurate combining of individual strategies.