Optimization of Gelatine Synthesis from Lime Fleshed Hide Trim Solid Waste

Abstract

This research takes a “waste to wealth” approach, generating useful products from solid tannery waste. It focuses on the production of gelatine from solid waste calcareous hide trimmings, which pollute the environment due to their high levels of lime, sulphide, fat, and protein. The lime trim contains the majority of the collagen so gelatine can be extracted from the cuttings using alkalis such as potassium hydroxide. Gelatine was extracted from waste using an alkaline and hydrothermal treatment method with potassium hydroxide. The most important factors in extracting gelatine from waste were found to be time, concentration, and temperature, with values of (1, 2, 3) h, (0.5, 0.75, 1) M, and (60, 70, 80) °C, respectively. The optimum conditions were 70 °C, 2 hours, and 0.75 M, as determined by optimization using Design-Expert software, and the optimum protein content was 87.25% using the Kjeldahl method for protein content analysis. After extraction, the gelatine has a viscosity of 240 cp, a gel strength of 245 g, a pH of 7.2, and a moisture content of 12.11%. This research can be fully utilized to reduce the cost of waste disposal and waste containers in the solid waste of leather tanneries while possibly generating additional revenue.