Biodetoxification of Aflatoxin M1 in Artificially Contaminated Fermented Milk, Fermented Dairy Drink and Yogurt Using Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus reuteri, and Lactobacillus rhamnosus and Its Effects on Physicochemical Properties

Abstract

The aim of this research was to examine the occurrence of aflatoxin M1 (AFM1) in milk collected from Shiraz, Iran. Moreover, the capacity of the four probiotic species to reduce the concentration of AFM1 was assessed. For this research, 10 raw milk samples were collected randomly in Shiraz, Iran, in January 2023. The analyses were performed using an HPLC system equipped with a fluorescence detector. Then, AFM1 artificially contaminated probiotic drink milk (PDM) containing Lactobacillus plantarum (LP), Lactobacillus reuteri (LRE), Lactobacillus rhamnosus (LR) (LABs) alone or in combination, fermented dairy drink containing Lactobacillus acidophilus (FDD-LA), and yogurt were produced. The pH, total viable number of probiotics (TVNP), and rheology of the samples were measured. In all milk samples, the concentrations of AFM1 did not exceed the maximum threshold established by Iranian national standards. In the artificially spiked samples, the maximal reduction in AFM1 was noted in PDM_LP (96.5%), PDM_LP-LRE-LR (95.3%), yogurt (95.2%), and PDM_LR (93.8%). FDD-LA revealed the lowest reduction in AFM1 (75.9%). The TVNP increased during processing, while the pH decreased in all the samples. AFM1 did not have any negative effect on TVNP or pH. The SEM images revealed that the AFM1-treated samples had a less compact structure and more cavities. Similarly, the viscosity of the control sample without AFM1 was greater than that of the AFM1-supplemented samples. The results showed that LP, LRE, LR, LA, and yogurt starter cultures have a strong ability to decrease AFM1 in milk. However, their effect on the textural properties of the product is not favorable.