Preparation and anti‐evaporation properties of organic–inorganic superabsorbent based on Tragacanth gum and clay

A comprehensive assessment of superabsorbent resin produced using modified quinoa husk and coal fly ash - Preparation, characterization and application

About 200 million tons of coal fly ash (CFA) is not effectively used in China every year. To enhance the utilization of biomass waste quinoa husk (QH) and solid waste CFA and reduce the preparation cost of superabsorbent resin (SAR), a low-cost, biodegradable modified quinoa husk-g-poly (acrylic acid)/coal fly ash superabsorbent resin (MQH-g-PAA/CFA SAR) was synthesized using modified quinoa husk (MQH), acrylic acid and CFA and used to improve the drought resistance and fertilizer conservation ability of soil. The surface morphology and performance of SAR were characterized by Fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA), which provided evidence for improving the properties of SAR by grafting MQH and adding CFA. In addition, the synthesis conditions were studied and optimized, together with the contents of initiator, crosslinker, MQH, and CFA to acrylic acid as well as the neutralization degree of acrylic acid. After optimization, the optimum water absorbency of SAR in deionized water, tap water, and physiological saline was 1302, 356, and 91 g/g respectively. The swelling and water-retention mechanisms of SARs were analyzed by a dynamic model and the results were in good agreement with the experimental data. In the soil experiment, the addition of SAR improved the drought resistance ability of soil, and reduced the leaching loss of fertilizer in the soil (from 49.5 % to 36.7 %). Therefore, this material exhibits significant potential in the field of agriculture and offers a novel approach with economic benefit for the utilization of MQH and CFA.

Enhancing hamburger shelf life and quality using gallic acid encapsulated in gelatin/tragacanth gum complex coacervate

Considering mitigating oxidative degradation and inhibiting microbial proliferation in meat products, incorporating antioxidant and antimicrobial materials is critical to enhance shelf life, maintain quality, and ensure food safety. So, this study aimed to investigate the antimicrobial and antioxidant effects of encapsulated gallic acid on the quality of hamburgers during 30 days of storage. Gallic acid was microencapsulated in tragacanth gum/gelatin complex coacervate, and its encapsulation efficiency was optimized by the response surface method. The optimized encapsulation conditions were 1:4 polymer ratio (tragacanth to gelatin ratio); total polymer content, 0.9 %; pH, 3.5; and gallic acid content, 0.88 %, resulting in a 98 % encapsulation efficiency. The microcapsules were characterized using various techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. 400 ppm encapsulated gallic acid was added to the hamburger formulation, and various microbial properties, chemical analysis (peroxide value (POV) and thiobarbituric acid (TBA)), and sensory properties of the hamburgers were evaluated during storage. Results showed that gallic acid in the hamburgers decreased lipid oxidation from 0.126 to 0.103 mg MAD/kg in the TBA test and 12.73 to 11.03 meq/kg in the POV test during one month of storage. Also, phenolic compounds could prevent the growth and proliferation of spoilage microorganisms by damaging the microorganism cell walls and changing the metabolic processes. So, the amounts of total count and yeast and mold in the treated sample were lower than in the control sample. Significantly, adding encapsulated gallic acid did not negatively affect the flavor or overall evaluation of the samples. Overall, these findings suggested that encapsulated gallic acid is a suitable candidate to maintain chemical, microbial, and sensory characteristics of hamburgers over time.

Preparation and fertilizer retention/anti-leakage performances of superabsorbent composite based on hydroxypropyl methyl cellulose

To reduce the preparation cost of superabsorbent composites (SACs) and improve the water and fertilizer retention properties of soil, hydroxypropyl methylcellulose grafted with acrylic acid, polyaspartic acid and palygorskite (HPMC-g-P(AA-co-PASP)/ATP) was synthesized by aqueous solution polymerization and used to reduce of preventing water leakage in soil. The structure, surface morphology and thermal stability of the optimized SACs were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and thermal gravimetric analysis. Under optimum synthesis conditions, the maximum equilibrium absorption of SACs was 1785 g·g^-1, 254 g·g^-1, 138 g·g^-1 in deionized water, tap water and NaCl solution (0.9 wt%) respectively. Application of the SACs to soils increased their water holding and water retention capacities. In addition, the reduced leaching of added urea and low water permeability of the treated soils indicated that the SACs has the potential for applications in future sustainable agriculture.