Abstract

Background:
Acrylamide is a food chemical hazard that can cause cancer in humans. French fries are among the food products with the highest acrylamide levels, and are the biggest contributor to acrylamide exposure in food. Potato peel waste, which is generated through the processing of French fries, is a rich source of phenolic compounds with the potential to prevent the formation of acrylamide.

Aim:
The aim of this study was to inhibit acrylamide formation in French fries using potato peel extracts containing phenolic compounds.

Methods:
Two potato cultivars (Kinigi and Kirundo) were processed into French fries. Five types of powdered potato peel extracts, namely, Kuruseke decoction extract (ExeD), Kuruseke ultrasound-assisted extract (ExeU), Peco decoction extract (ExPD), Peco ultrasound-assisted extract (ExPU), and T58 ultrasound-assisted extract (ExTU), were applied to French fries at four different concentration levels of dilution ratios (v/v): L1 (2:8), L2 (4:6), L3 (6:4), and L4 (8:2) of phenolic compounds to mitigate acrylamide formation. French fries strips were soaked in deionized water (control sample) and potato peel extract for 2 minutes before being deep-fried in a semi-automated fryer with sunflower oil at 175°C ± 5°C for 4 minutes. Acrylamide was quantified using QuEChERS extraction and a liquid chromatography-tandem mass spectrometer method. The data obtained were analyzed statistically.

Results:
The results showed that the potato cultivar significantly affected (p < 0.0001) acrylamide formation in French fries, with 217.91 ± 8.10 μg/kg and 349.87 ± 8.81μg/kg in Kinigi and Kirundo, respectively. Both the type and concentration of the peel extract had a significant (p < 0.0001) inhibition effect on acrylamide in French fries by 41.24% and 35.15% with the ExeU extract and the L3 (6:4) concentration, respectively. The interaction effect of potato cultivar, type, and concentration of peel extract on acrylamide formation was significant (p < 0.0001), with the highest acrylamide inhibition by 63.3% for Kinigi-ExeU-L3 French fries. There was a good relationship (p < 0.001) with a negative correlation (r = −0.665) between the concentration of phenolic compounds in potato peel extracts and acrylamide formation. Considering the impact of potato peel extract on acrylamide inhibition, this study, through logistic regression analysis, showed that the Kirundo cultivar was more impacted (ExTU: 0.822, p < 0.001) than the Kinigi cultivar (EXeD: 0.962, p > 0.05).

Conclusion:
This study demonstrated that a specific type of potato peel extract at a certain concentration can be used to produce acrylamide-safe French fries.

Key words: Acrylamide; French fries; Inhibition; Phenolics; Potato peel extracts.