Sustainable G-Polymer From Industrial Waste
This study focuses on the pre-treatment of paper sludge ash (PSA) as a by-product of paper milling industry that contains high amount of calcium, yet low in silica. The presence of high calcium content in geopolymer system will accelerate the setting time of fresh geopolymer and may disrupt the development of its mechanical strength. Therefore, in this study, the refinement of PSA properties was conducted by treating raw PSA in hydrochloric acid solution with different molarities of 0.5 M, 1.0 M and 2.0 M. The pre-treatment process was mainly purposed to decrease the amount of calcium and other impurities through leaching mechanism. Based on the experimental results, 2.0 M hydrochloric acid solution (HCl) was determined as the optimum concentration due to its ability in removing higher amount of calcium from the ash, yet still able to increase the amount of silica. Compression test on the hardened properties of geopolymer specimen also showed the deceleration of fresh fly ash based geopolymer and produced a more workable fresh geopolymer.
New Approach to Food Packaging: Antimicrobial and Edible Materials
In addition to adequate and balanced nutrition in the protection of human health, the reliability of consumed foods is also of great importance. When foods contact with the environment, they are undergoing many microbiological, physical and chemical changes such as moisture loss, aroma exchange, oxidation and contamination with microorganisms. So this changes reduce quality and shorten the shelf life. During cutting and processing of chicken meat, especially contamination on the surface causes deterioration of the meat starting from the surface and thus short shelf life. Though contamination of chicken meat surface is inevitable, growth of contaminant microorganisms can be inhibited and microorganisms can be killed. In recent years, increased risks of infection due to antibiotic-resistant microorganisms have forced the discovery of new and natural antibacterial materials. It is a new and advantageous approach to avoid environmental pollution caused by the use of food packaging and safety of food, prolongation of product shelf life by natural, edible, antibacterial biomolecules in packaging products. In the scope of the project, in order to produce an edible alginate gel containing the antimicrobial peptide nisin, which has an antibacterial property to prevent microbial growth on the surface of chicken meat, following steps was done; Synthesis of calcium alginate and nisin immobilized calcium alginate beads Optimization of immobilizing nisin in calcium alginate beads, Characterization of nisin immobilized calcium alginate beads by ATR-FTIR Spectrum and SEM Analysis, Determination of the antimicrobial activity of white meat product chicken which is coated by nisin immobilizing calcium alginate gel.