Characterization of Siam Orange Peel Pectin Using NADES and Pre-Treatment of Pressing Temperature

Pectin has been widely used as a gelling agent, thickener, and stabilizer, especially in the food industry. Pectin is obtained by extracting plant parts such as orange peel. Solvents are needed in the pectin extraction process. Usually, inorganic solvents used, such as HCl and H₂SO₄, have negative impacts on researchers and the environment. In this study, NADES (Natural Deep Eutectic Solvent) was used with citric acid and sucrose, which are safer and more environmentally friendly. Pre-treatment by pressing was carried out to reduce the water content so that the orange peel could be changed into a simplex and ready to be extracted from its pectin. This study aims to see the effect of pre-treatment pressing temperature and the ratio of materials and volume of NADES on the characteristics of the pectin produced. The results showed that pre-treatment pressing temperature and the ratio of materials and volume of NADES had a significant effect (p <0.05) on the equivalent number, methoxyl content, galacturonic acid content, degree of esterification, and water content.