First International Conference on MOLDAVIAN RISKS – FROM ...

<strong>First</strong> <strong>International</strong> <strong>Conference</strong> on MOLDAVIAN RISKS - FROM GLOBAL TO LOCAL SCALE
16-19 May 2012, Bacau, Romania
FRIENDLY ENVIRONMENTAL TECHNIQUES USED TO
IMPROVE THE EFFICIENCY OF EXTRACTION FROM LULA
(PERSIA AMERICANA)
B. U. Saha 1, 2 , G. Kansci 1 , E. Fokou 1 , I. M. Lazar 2 , F. X. Etoa 1
1 University of Yaoundé I, Cameroon, Department of Biochemistry
1 ”Vasile Alecsandri” University of Bacau, Department of Chemical and Food Engineering,
Romania
Corresponding author: Brice Ulrich Saha Foudjo, sahabrice@yahoo.fr
Abstract: Cameroon is one of the best avocado producers in Africa. However, for a few
years, it has been noticed that local markets have oriented their demands towards some
specific varieties, leaving aside others that are less appreciated by consumers. If nothing is
done, the consequence will be the increase of Cameroon-grown avocado post-harvest
losses. Therefore, redefining an existing extraction method that takes in consideration the
financial worries of producers, the environment related issues of solvent use and the
balance that should exist between having a high yield and gaining excellent functional
properties will be a breakthrough for Cameroon. Among extraction techniques, the
aqueous extraction method, less expensive and non-pollutant, leads unfortunately to a very
low yield. This study aims to improve the yield of avocado oil extraction with this
aforementioned friendly environmental technique. The avocado cultivar Lula, harvested on
the farm of the National Research Institute of Agriculture and Development in Foumbot
(Cameroon), was used for oil extraction. Lipid content was first assessed with the Soxhlet
method, and then water extraction process, relying on Bizimana et al. method (1993), was
performed. From it, the oil yield was obtained and the extraction efficiency EE, oil yield to
lipid content, was deduced. The effect of four factors on water oil extraction, namely:
temperature (T), time (t), pH and water-to-pulp ratio (WPR), was investigated. A two-level
full factorial design 2 4 , was conducted to describe a first order mechanism of the extraction
kinetic under the response surface methodology (Barros et al., 1996). The results showed
that T, WPR and t had a positive effect on the yield whereas the pH had a negative effect
on the entire process. The mathematical model that fitted a first order regression equation
is EE=29.6821+ 3.7291*T + 1.0229*t – 3.9868*pH + 2.3599*WPR. It shows the effect of
the individual parameters. The optimal conditions for oil extraction WPR=4, pH=4.5,
T=55°C and t=180 min were found. The highest extraction efficiency obtained was
40.78%. The model obtained in this study has well defined the extraction procedure and
the aqueous medium was found to be suitable for avocado oil production with good
efficiency with respect to our criteria.
Keywords: avocado, oil yield, extraction, optimization, response surface methodology, environment.
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