Factors affecting acrylamide mitigation in fried potatoes

Tóm tắt

Introduction: Recent findings of acrylamide, a carcinogenic agent to humans, in foods have led to great efforts to elucidate the mechanisms of acrylamide formation and its mitigation. The acrylamide was generated during the browning process by the Maillard reaction of amino acid asparagine and reducing sugars at temperatures above 120 ◦C. Asparagine was determined to be a precursor of acrylamide formation. Therefore, asparagine reduction in raw materials can be taken into account to limit the acrylamide level in prepared foods. L-asparaginase has been used to consume acrylamide precursor by catalyzing the conversion of asparagine into aspartic acid and ammonia. Several factors including enzyme concentration, pH, temperature and frying time can influence the efficiency of acrylamide mitigation by enzyme. In the present work, we selected potatoes as raw materials to investigate the effects of factors on the acrylamide mitigation in fried potatoes.

Methods: By pre-treating potato strips in different conditions of enzyme concentrations, pH, temperature and frying time, the effects of these parameters on acrylamide levels in fried products were evaluated by measuring UV-Vis spectra of sample solutions containing acrylamide. The maximum absorbance values at 224 nm were used to determine the acrylamide concentrations by calculation from a calibration curve. Experimental data were statistically analyzed by one-way ANOVA. Colorspace measurements were performed to describe the differences in colors of the fried products after various frying times.

Results: A calibration curve was established to determine the acrylamide content of sample solutions via their maximum absorbance values. Pre-treatment of
potato strips with a solution of 1.0 IU/mL asparaginase at 37 ◦C, pH 7.3, for 30 min led to a 45.6% reduction of acrylamide in French fries compared to a solution without enzyme. The optimum pH value for the most efficient enzyme activity was 7.3. Frying time ranging from 1.0 to 6.0 min increased acrylamide content and induced a darker appearance product.

Conclusions: By using UV-Vis measurements, we demonstrated the effects of factors on L-asparaginase based acrylamide mitigation in fried potatoes. The conditions which gave the lowest acrylamide concentrations were assessed. The results could be applicable for commercial processes to minimize acrylamide content in prepared potatoes.