Enhancing the Physical Characteristics and Shelf Life of Rice Water (Oryza Sativa L.) Gel Shampoo: The Role of Propylene Glycol Concentration

Objective: This study aims to determine the effect of variations in propylene glycol concentration on the physical properties and physical stability of rice water shampoo gel and the physical strength of rice water shampoo gel preparation. Methods: The active ingredient was rice water, which was prepared by washing rice with water at the proportion of 1:1. The rice water then was applied to HPMC K4M-based gel preparations and further designed to prepare shampoo gel with varying concentrations of propylene glycol 8%, 10%, and 12%. The rice water shampoo gel was evaluated for its organoleptic properties, pH, viscosity, spreadability, flowability test, softness test, and physical stability test. Results: The results of the physical properties test on the three formulas produced an organoleptic clear pale yellow color, lemon odor, and semi-solid shape. The pH test results obtained by F1 was 7.24±0.08, F2 was 5.89±0.01, and F3 was 6.02±0.01. The viscosity test results obtained by F1 amounted to 2082±80.07 cP, F2 amounted to 4987±883.88 cP, and F3 amounted to 6531±232.79 cP. The foam height test results obtained by F1 amounted to 4.6±2.11 cm, F2 amounted to 1.46±0.05 cm, and F3 amounted to 1.7±0.17 cm. Variations in propylene glycol levels affect the physical properties of shampoo gel preparations at pH, viscosity, and foam height but do not affect the organoleptic practice. The stability test that was conducted at weeks 0, 1, 2, 3, and 4 with varying levels of propylene glycol showed significant changes on viscosity and foam height stability. Conclusion: Variations in the concentrations of propylene glycol in the three formulations affect the physical but have no effects on the pH stability of the rice water shampoo gel preparation.