Study on the colorimetry determination conditions of pectin in fruits and derived products
In order to research the determination method of pectin content in fruits and derived products, coloring conditions of sulfuric acid-carbazole eolorimetry including absorption wavelength, amount of car- bazole-ethanol solution and sulfuric acid, temperature, reaction time, and stabilization time after coloring were optimized using galaeturonic acid as standard substance. The results showed that the optimum color- ing conditions were adding 0.25 mL 0.1% carbazole-ethanol solution and adding 5.0 mL sulfuric acid quickly to 1.0 mL filtrate, water bathing for 20 min at 85 ~C, cooling down quickly with running tape water bath, and measuring at 525 nm wavelength within 1.5 h after coloring. Under the conditions, it had wide linear range standard curve, good correlation, high precision and accuracy, and were in line with relevant standards.
国家科技期刊平台
NSTL
万方数据
维普
