Background: In recent years, the development of efficient and green route to synthesis metal nanoparticles has gained considerable attention in various areas of nanotechnology. Among metal nanoparticles, silver nanoparticles (AgNPs) have attracted much interest because of their potential antimicrobial agents and they are widely applied in many biological and medical fields. With respect to Ag-based nanocomposites, chitosan-silver nanoparticles (Ch-AgNPs) represent an emerging group of bio-nanostructured hybrid materials due to their biocompatibility and biodegradability. Ch is considered a non-toxic biopolymer, as well as its antimicrobial and antifungal activities against a wide range of microorganisms. Methods: Colloidal AgNPs were prepared by chemical reduction of silver ions in the presence of Ch giving Ch-AgNPs. Physiochemical characterizations were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), and zeta potential. In vitro antibacterial activity was evaluated against Escherichia coli and Salmonella typhimurium using nutrient agar dilution method. The in vivo antibacterial activity was also tested against E. coli in minced meat under aerobic conditions at 4°C for 10 days. In addition, different biochemical parameters were determined in minced meat samples. Results: The colloidal AgNPs formed in situ by chemical reduction of Ag ions in the presence of Ch and showed a good stability. SEM and XRD confirmed the formation of nanoparticles. Zeta potential value was decreased by increase the ratio of Ag and was found to be − 0.225, − 0.193, and − 0.0695 mV for Ag ratio 0.1, 0.2, and 0.35, respectively. The in vitro antibacterial activity of Ch and Ch-AgNPs against E. coli and S. typhimurium reveal that the E. coli was more susceptible to these products than S. typhimurium and Ch-AgNPs have more influence with increasing of the silver concentrations. The in vivo antibacterial activity against E. coli in minced meat samples showed that the effect of Ch-AgNPs was a concentration dependent and greater compared with either controls or Ch alone. Conclusions: The results suggest that Ch-AgNPs could be used in food preservation as antimicrobial agents and for shelf-life extension. However, further toxicological studies on mammals are needed.

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K IDNEY beans (Phaseolus vulgaris L) are rich source of nutrients. Effect of soaking for 12hr and boiling after soaking processes on some constituents of white kidney and red kidney beans was performed. Determination of some anti-nutritional factors (Phytic acid and trypsin activity), vitamins, and minerals was achieved using standard procedures. Chemical composition of raw white kidney bean powder was 9.54, 2.05, 2.31, 3.09, 73.06 and 9.95 g/100gwhile it was 17.47, 1.4, 2.9, 5.63, 64.75 and 8.03g/100g, in red kidney beanfor protein, fat, crude fiber, ash, carbohydrates and moisture contents, respectively. The results showed significant differences in the levels of estimated anti-nutritional factors between raw beans and after soaking and boiling processes of kidney beans. The reduction percentages of phytic acid were 15.23, 60.95 and 35.89. While the reduction percentage of trypsin activity were 60.20, 65.30 and 26.87 in white and red kidney beans respectively after soaking and boiling processes compared with raw kidney beans. Generally, soaking and boiling reduced significantly (p<0.05) all the anti-nutritional factors and vitamins content of kidney bean. However, the levels of the three minerals (K, Ca and Mg) increased compared with rawbeans. The sensory score of overall acceptability was 6.50 and 8.74 out of ten for white and red kidney bean burger which revealed the acceptability of prepared burger. The current study showed that, burger of red bean are rich sources of protein thus could be useful vegetarian people in their nutrition programs as alternative for beef to improve the health status and prevent chronic diseases.

Nowadays, food industry developing a range of plant-based milk as alternatives to cow milk in order to meet the requirement of protein in developing countries mainly for individuals suffering from lactose intolerance. Rice, oat and coconut milk are a plant-based milk alternative, which are rich in nutritional value. White chocolate was prepared from cow, rice, oat and coconut milk. The result of chemical composition of cow white milk chocolate showed no significant difference in the protein contents compared to white chocolate prepared from plant based milk. Coconut chocolate contains the highest percent of fat (58.30%) and fiber (5.40%) compared to white milk chocolate which showed (54.7%) of fat and non-fiber. The oat chocolate has the highest percentage of carbohydrates (44. 0%).Minerals results showed that calcium was high in cow and rice white milk chocolate and coconut white milk chocolate was high in potassium. The pH values of plant based milk were close to cow milk. Antioxidants activity of coconut white milk chocolate was the highest (64.60%) compared to other prepared chocolate. HPLC analysis of sugar profile extracted from cow milk chocolate showed the presence of lactose sugar at a rate of 3.90%, and its absence in chocolate prepared from plant-based milk. The sensory evaluation of white chocolate revealed that the overall acceptability of coconut chocolate, was more followed with oat, rice and the cow milk chocolate. This study provides new visions for plant-based milk alternatives which have high nutrients values to meeting the needs of lactose intolerant people.