Non-Destructive Quantitative Analysis of Azodicarbonamide Additives in Wheat Flour by High-Throughput Raman Imaging

Abstract

Azodicarbonamide (ADA) additives are limited or prohibited from being added to wheat flour by various countries because they may produce carcinogenic semicarbazide in humid and hot conditions. This study aimed to realize the non-destructive detection of ADA additives in wheat flour using high-throughput Raman imaging and establish a quantitative analysis model. Raman images of pure wheat flour, pure ADA, and wheat flour-ADA mixed samples were collected respectively, and the average Raman spectra of each sample were calculated. A partial least squares (PLS) model was established by using the linear combination spectra of pure wheat flour and pure ADA and the average Raman spectra of mixed samples. The regression coefficients of the PLS model were used to reconstruct the 3D Raman images of mixed samples into 2D grayscale images. Threshold segmentation was used to classify wheat flour pixels and ADA pixels in grayscale images, and a quantitative analysis model was established based on the number of ADA pixels. The results showed that the minimum detectable content of ADA in wheat flour was 100 mg/kg. There was a good linear relationship between the ADA content in the mixed sample and the number of pixels classified as ADA in the grayscale image in the range of 100 -10,000 mg/kg, and the correlation coefficient was 0.9858. This study indicated that the combination of PLS regression coefficients with threshold segmentation had provided a non-destructive method for quantitative detection of ADA in Raman images of wheat flour-ADA mixed samples.

Effect of azodicarbonamide on rats with a high-fat hypercaloric diet

“…Azodicarbonamide is reported to be one of the fast-acting food oxidizers and it is also used for leavening baked goods, rice, chewing gum, flour and grains. Many scientific works are devoted to the detection and quantification of azodicarbonamide and its metabolites in food (Ye et al, 2011;Xing et al, 2012;Chen et al, 2016;Yasui et al, 2016;Wang & Chan, 2016;Che et al, 2017;Wang et al, 2018;Chen et al, 2021;Wang & Zhao, 2021;Zhang et al, 2021).…”