Shelf life analyses of Jatropha curcas L. oil extracted with mechanical and aqueous enzymatic procedures

Publication Type

Poster

Authors

Karaj, S; Latif, S; Müller, J

Year of publication

2013

Published in

Euro Fed Lipid Congress, Book of abstracts

Page (from - to)

347

Conference name

11th Euro Fed Lipid Congress and 30th ISF lecture series – New strategies for High Quality Future

Conference location

Antalya, Turkey

Conference date

27 - 30 October, 2013

Keywords

Jatropha, oilseeds

Mechanical extraction (ME) and aqueous enzymatic extraction (AEE) of oilseeds are becoming attractive for extracting oil in decentralized systems. The oil produced for household energy should not require to be highly processed, in order to produce it locally at low costs. Low processing procedures leads to reduction of shelf life and deterioration of oil chemical properties. The objective of this study was to investigate the effect of ME and AEE process on chemical properties of Jatropha oil during storage conditions (20 – 25 °C, period of two months). The chemical properties were analyzed following the guidelines laid by Deutsches Institute für Normung (DIN). Moreover, the chemical properties of ME raw, sedimented, and AEE oils with/without centrifugation were analyzed and compared with standard DIN 51605. Among the characteristic chemical properties only the kinematic viscosity of ME raw and sedimented oil exceeded the threshold of DIN 51605. Acid value remained constant for 28 days of sedimentation and then increased, indicating initialization of oxidation processes. The oxidation stability index (OSI) of ME raw and sedimented oil and AEE with centrifugation was 18.5, 10.1 and 6.1 hours, respectively. Vitamin E, known as natural antioxidant of plant oils decreased from 330 to 215 mg/l for raw and sedimented oil, respectively. Whereas, vitamin E of AEE process was about 300 mg/l with centrifugation process showing a low value compared to ME process of raw oil. Shelf life characteristics based on chemical properties prone to deterioration (acid value, oxidation stability index, vitamin E) were determined and storage recommendations were drawn.