Amr Amer

The existence of aflatoxin M₁ (AFM₁) in raw milk results in economic losses and public health risks. This research aims to examine the capability of bentonite to adsorb and/or eliminate AFM₁ from various raw milk types. In addition, the effects of numerous bentonites (HAFR 1, 2, 3 and 4) on the nutritional characteristics of the milk were studied. Our findings revealed that goat milk had the highest value of AFM₁ (490.30 ng/L) in comparison to other milks. AFM₁ adsorption was influenced by applying bentonite (0.5 and 1 g) in a concentration-dependent manner for different time intervals (from 0 to 12 h). The percentage of AFM₁ reached the maximum adsorption level after 12 h to 100, 98.5 and 98% for bentonites HAFR 3, 1 and 2, respectively. HAFR 3 (1 g bentonite) presented higher adsorption efficiency than other bentonites used in the phosphate buffer saline (PBS) and milk. Residual levels of AFM₁ reached their lowest values of 0 and 1.5 ng/L while using HAFR 3 in PBS and milk, respectively. With regard to the influence of bentonite on the nutritional characteristics of milk, there was an increase in fat, protein and solid non-fat ratio while using HAFR 3 and 4, yet decreased lactose in comparison with the control. Scanning Electron Microscopy and Fourier Transform-Infrared Spectroscopy both identified bentonites as superior AFM₁ binders. The results demonstrated that bentonite, particularly HAFR 3, was the most effective adsorbent and could thus be a promising candidate for the decontamination of AFM₁ in milk.

The high incidence of aflatoxins (AFs) in chocolates suggests the necessity to create a practical and cost-effective processing strategy for eliminating mycotoxins. The present study aimed to assess the adsorption abilities of activated charcoal (A. charcoal), yeast (Saccharomyces cerevisiae), and the probiotic Lactobacillus rhamnosus as AFs adsorbents in three forms—sole, di- and tri-mix—in phosphate-buffered saline (PBS) through an in vitro approach, simulated to mimic the conditions present in the gastrointestinal tract (GIT) based on pH, time and AFs concentration. In addition, the novel fortification of chocolate with A. charcoal, probiotic, and yeast (tri-mix adsorbents) was evaluated for its effects on the sensory properties. Using HPLC, 60 samples of dark, milk, bitter, couverture, powder, and wafer chocolates were examined for the presence of AFs. Results showed that all the examined samples contained AFs, with maximum concentrations of 2.32, 1.81, and 1.66 µg/kg for powder, milk, and dark chocolates, respectively. The combined treatment demonstrated the highest adsorption efficiency (96.8%) among all tested compounds. Scanning electron microscope (SEM) analysis revealed the tested adsorbents to be effective AF-binding agents. Moreover, the novel combination of tri-mix fortified chocolate had a minor cytotoxicity impact on the adsorptive abilities, with the highest binding at pH 6.8 for 4 h, in addition to inducing an insignificant effect on the sensory attributes of dark chocolate. Tri-mix is thus recommended in the manufacturing of dark chocolate in order to enhance the safety of the newly developed product.

This study aims to assess the occurrence of Staphylococcus aureus in chicken fillets and to control its growth using various lyophilized seaweed extracts (i.e., Halimeda opuntia (HO), Actinotrichia fragilis, and Turbinaria turbinata) by an agar disk diffusion assay in vitro. Results showed that prevalence of S. aureus in breast and thigh samples reached of 92% and 84%, respectively. Lyophilized HO extract was the only seaweed that showed the antibacterial activity against S aureus with a significant difference at p < 0.05. The minimum inhibitory concentration (MIC) of HO extract was 1.5%, with an inhibition zone of 8.16 ± 0.73 mm. Regarding 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, IC₅₀ was recorded at 55.36 μg/mL, whereas cytotoxic IC₅₀ of the lyophilized HO extract on peripheral blood mononuclear cells (PBMCs) was 33.7 µg/mL; a higher IC₅₀ of HO extracts permits their use as a safe food additive in meat products. Moreover, total phenolic compounds and total flavonoids compounds recorded 20.36 ± 0.092 and 16.59 ± 0.029 mg/mL, respectively. HPLC analyses of phenolic compounds profiles exhibited many bioactive substances and the higher ratio was daidzein with 10.84 ± 0.005 µg/mL and followed by gallic acid with a value of 4.06 ± 0.006 µg/mL. In a challenge study, chicken fillet (CHF) experimentally inoculated with S. aureus (ST) and treated with the lyophilized HO algal extract at 4% and 6% (CHF/ST/HO) showed a complete reduction of S. aureus count on the 6th and 4th days in chicken fillet stored at 4 °C, respectively. Moreover, CHF/ST/HO at 4% and 6% of HO extract enhanced the sensory attributes of grilled un-inoculated chicken fillet. Thus, lyophilized HO extracts are promising antibacterial and antioxidant candidates in the chicken meat industry.

Camel milk is one of the most important sources of nutrition and a cure for the population in many arid regions. Raw camel milk from the healthy lactating camel is nearly sterile at secretion, contamination of milk can take place at any stage of milk production and processing; therefore, it may lose its quality and safety standards. Therefore, the aim of this study to evaluate the microbial quality of 100 raw dromedary camel milk samples obtained from markets and farms in Matrouh Governorate, Egypt throughout 4 months (from October 2019 to January 2020). The obtained results revealed that the mean pH values of raw dromedary camel milk samples collected from markets and farms were 6.41±0.13 and 6.42±0.15, respectively. Only 7 (14%) and 2 (4%) of the examined samples did not comply with DK standards. The respective mean count (log10 CFU/ml) of aerobic bacterial, psychrotrophic bacterial, Staphylococcus aureus, Coliforms, Enterococci and yeast were 7.61 ± 0.83; 7.72 ± 0.70; 4.50 ± 1.69; 7.44 ± 0.51; 5.27 ± 0.45 and 5.45 ± 0.68 in market milk samples while in farm milk were 5.10 ± 1.67; 5.04 ± 1.19; 2.70 ± 1.46; 4.75 ± 0.92; 3.11 ± 1.28 and 3.61 ± 0.84. Most of the examined raw camel market milk was regarded as grade III ( <6.30 log10 CFU/ ml) according to dairy Kenya standards (DKS, 2061:2016) for the aerobic bacterial count (68%) and Coliforms count (54%). E. coli (24%) and Enterobacter aerogenes (18%) were the most predominant Coliforms isolated from examined samples. These germs can limit the keeping quality and safety of raw camel milk. There is a requisite to improve the hygienic status and providing adequate sanitary procedures from the point of production until milk consumption.