Seyed-Ahmad Shahidi

Acrylamide is a chemical that can form in some foods during high‐temperature cooking processes and is a known carcinogen according to the International Agency for Research on Cancer (IARC). Since biscuit consumption is high amongst Iranians, especially children, and there is a risk of exposure to hazardous compounds such as acrylamide, the purpose of this study is to investigate the amount of acrylamide in some types of biscuits. In this study, graphene (G) modified with magnetite (Fe ₃ O ₄ ) and sol–gel hybrid tetraethoxysilane methyltrimethoxysilane (TEOS‐MTMOS) or MSPE (magnetic solid phase extraction) and GC/MS (gas chromatography–mass spectrometry) method was used to measure acrylamide. The calibration curve, LOD (detection limit), LOQ (quantification limit), RSD (Relative standard deviation), recovery, and linear r ² (correlation coefficient) were 0–200 ng/g, 19 μg/kg, 58 μg/kg, 9.64%, 96%, and 0.9982, respectively. The results displayed that the highest level was observed in the biscuits sample with cardamom essential oil (9.01 mg/kg) and the lowest level was observed in the saffron biscuits sample (0.15 mg/kg). According to the results, the mean ± SD of all samples was 1.739 ± 0.830 mg/kg, which being higher than 0.35 mg/kg can be higher than the EU (European Union) standard level. Our results also indicated that biscuits containing essential oil (mean = 4.510 mg/kg) were more contaminated than biscuits containing natural additives (mean = 0.806 mg/kg). Monte Carlo simulation results showed the THQ (Target Hazard Quotient) and ILCR (Incremental Lifetime Cancer Risk) associated with exposure to acrylamide via biscuits for adults were 2.52E‐1 and 2.48E‐4; and for children were 8.75E‐1 and 8.47E‐4, respectively. Uncertain analysis of human health risks by consumption of biscuit samples contaminated with acrylamide showed a serious non‐carcinogenic risk (95th percentile; THQ > 1) for children and a carcinogenic risk (ILCR > 1E‐4) for children and adults. Consequently, there is a significant carcinogenic risk from biscuit consumption.

This study aimed to extract biosurfactants from lactobacilli present in traditional yogurt and evaluate their emulsifying and antioxidant performance in emulsions formed with various oils. First, yogurt samples were cultured in MRS medium, resulting in the isolation of 19 isolates (N1–N19). Morphological analyses and chemical tests on the colonies showed that seven isolates belonged to the Lactobacillus genus. Next, hemolysis, oil spread, drop collapse, and emulsification index tests were conducted. The results indicated that none of the isolates exhibited hemolytic activity; however, isolates N4 and N18 demonstrated good performance in oil spread (8.1 ± 0.16 cm and 7.4 ± 0.04 cm, respectively) and droplet collapse (droplets with diameters larger than 1 cm) tests, also showing high emulsification index (42.49 ± 0.81 and 39.05 ± 0.32, respectively) at this stage. The two isolates, N4 and N18, were identified using PCR techniques and were named Lactobacillus plantarum LBp_WAM and Lactobacillus rhamnosus DSA LR1, respectively. Biosurfactant extraction and purification were then performed on these strains, and emulsification index, emulsion stability, and creaming index tests of the biosurfactants were conducted on emulsions formed with olive, canola, sunflower, and rice bran oils. The results showed that the biosurfactants had high emulsification index, although their effect was less than that of Tween 80. Finally, the assessment of oxidation levels indicated that the emulsions prepared with biosurfactants were significantly less oxidized compared to the control sample. The findings of this research introduce the biosurfactants derived from L. plantarum and L. rhamnosus as natural biosurfactants for emulsion preparation, particularly with olive and canola oils.

This study investigated the possibility of using amaranth protein isolate (API) as a plant‐based substitute for egg yolk (EY) in the preparation of low‐fat mayonnaise (LFM). The alkali extraction/acidic precipitation method was used to isolate amaranth protein; its functional properties were then studied. The results showed that besides its great water and oil absorption capacities, API had better emulsifying capacity and significantly higher (p < .05) emulsion stability at pH 2.0 than alkali pH values. Five mayonnaise samples with different API/EY combination ratios (%) (i.e., 0/0.75, 0.25/0.5, 0.375/0.375, 0.5/0.25, and 0.75/0) were prepared. The color, emulsion stability (ES), freeze–thaw stability (FTS), droplet size, structure, rheology, and sensory properties of samples were examined. API replacement showed no adverse effects on the L* value, ES, and sensory attributes (p > .05). Low API concentrations (0.25% and 0.375%) significantly (p < .05) increased the droplet size and decreased the FTS of LFM emulsion. High API concentrations (0.5% and 0.75%) had no significant effect (p > .05) on droplet size and formed emulsions with more tightly packed oil droplets. The Cross model was chosen best to describe the flow behavior of LFM samples (R² = 0.99). The sample with 0.75% API had significantly (p < .05) the highest values of η_o (zero‐shear viscosity) and λ (relaxation time), indicating greater interaction between the emulsion particles. All samples showed a weak gel structure (G' > G"). In conclusion, API can be considered an appropriate substitute for EY in LFM production, which can benefit human health and offer a new strategy for preparing vegan products.