三种坚果类食品壳提取物的抑菌性比较研究

本实验采用滤纸片法探讨了花生、板栗和葵花子壳乙醇提取物对六种食品中常见污染菌的抑菌性,不同pH下抑菌活性的变化、提取物热稳定性和对食品防腐作用研究等。结果表明:三种提取物对六种试验菌均有很强的抑制作用,它们的抑菌性受pH影响很大,且抑菌性有很好的热稳定性。防腐实验研究表明,在48h内它们对3种试验食品的抑菌率大都在80%以上,最高达94.20%。它们能很好地保存食品的风味。

新疆部分特色林果果壳的抗菌活性研究

目的:研究新疆特色林果核桃、巴达木果壳乙醇提取物的抑菌特性。方法:用滤纸片法检验果壳乙醇提取物对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌和变形杆菌的抑菌活性,通过液体培养基稀释法测定最低抑菌浓度。结果:巴达木乙醇提取物(25%乙醇提取10 h)对大肠杆菌有较好的抑菌效果,最低抑菌浓度(MIC)为25%;核桃乙醇提取物(25%乙醇提取24 h)对大肠杆菌有较好的抑菌效果,MIC为6.25%。结论:核桃、巴达木果壳乙醇提取物对受试菌具有较好的抑菌效果,为进行大规模开发利用提供了有效依据。

Elaboration and Characterization of a Hybrid Composite Material with Two Particles of the Same Size: Coco Shells and Palm Shells

This work aims to develop and characterize a hybrid composite material with two particles of the same size. As reinforcing particles, the hulls of palm nuts and coconut are chosen. Hybrid composite material composites in the form of specimens were produced by molding at 10%, 20% and 30% mass fractions in various sizes (0.63 mm, 1.25 mm and 2.5 mm). The samples were physically characterized (water absorption rate, moisture content, actual, theoretical and apparent density) and mechanical in 3-point flexion. The main results are: the highest and minimum water absorption rate are respectively 3.57% and 0.67% for respectively particle sizes 1.25 mm (sample P10C30) and 0.67% in the size of 0.63 mm (sample P10C10). The moisture content varies from 0.64 to 7.14% respectively for the P20C20 (2.5 mm) and P10C30 (2.5 mm) samples. The maximum and minimum real density are 1340,518 Kg/m3 and 1055.981 Kg/m3, for respectively the composites of particles sizes 1.25 mm (P20C10) and 0.63 mm (sample P20C20). The minimum real density is Its maximum theoretical density is 1194.949 Kg/m3 (for samples P20C10, P10C10 and P30C10);however, the minimum is 1189.966 Kg/m3 (P10C20 and P20C20). The bulk density varies from 933.28 Kg/m3 to 1176.1 Kg/m3, respectively, in sizes from 2.5 mm (P10C30) to 0.63 mm (for P10C30). As for the mechanical characteristics, the Modulus of Elasticity (MOE) varies from 25.664 GPa to 25.759 GPa, respectively, the samples P10C10 (1.25 mm) and P10C20 (2.5 mm). The MOE values describe a parabola whose peak is reached when the palm shell loads are 20%, that is to say P20C10, whatever the particle size distribution. In resilience, samples with small particles are more resilient with a maximum value of 22.49 J/cm2 and a minimum value of 4.45 J/cm2 to verify the principles of Hall-Petch’s law.