Extraction, Characterization and Properties of the Gel of Aloe Vera (Aloe barbadensis Miller) Cultivated in Chile

Abstract

This work describes the chemical characterization of Aloe vera leaves after dissecting the whole leaf into filets and skin, and characterizes the mucilaginous gel extracted from the filets. Gel was extracted by hand-fileting the leaves and pressing the resulting filet. The mean gel yield was 86.3% from the whole filet and the volume of freeze-dried gel was 0.91% that of fresh gel. The volume of the pressed fresh residue (cake) of the filet after extracting the gel was 15.1% that of the whole filet. The fresh gel had a moisture content of 97.8%, a pH of 5.24 and 0.07% acidity expressed as malic acid. Water content analysis of the freeze-dried gel and dehydrated cake revealed moisture values of 2.3% in the gel and 6.9% in the cake. The ash content was 17.20% in the gel and 13.15% in the cake. The total dietary fiber determined in the cake (71.5%) was greater than that of freeze-dried gel (64.8%), and water retention capacity (WRC), swelling (SW) and fat adsorption capacity (FAQ) were higher in the cake than in the gel. Aloin and polysaccharides were also determined in both the freeze-dried gel and cake. Antioxidant activity was greater in freeze-dried gel (46.7%) than in fresh gel (36.7%). This study aims to analyze the process by which gel and latex is extracted from aloe vera grown and utilized in Chile, comparing it with other Aloe barbadensis varieties cultivated elsewhere. Keywords Aloe vera; Gel powder; Polysaccharides; Antioxidant activity; Phytochemical analysis