Enjeux et amélioration de la réduction de l'acidité dans les fruits mûrs du palmier à huile, Elaeis guineensis, Jacq. (synthèse bibliographique)

Reduction of acidity in mature oil palm (Elaeis guineensis Jacq.) fruits: stakes and oil quality improvement. A review. Introduction. Palm oil acidification determines the quality and stability of this important foodstuff. This review article analyzes the causes of acidification, and its effects on the quality and stability of palm oil. The stakes involved in the reduction of acidity in fruits and the approaches used are also analyzed, especially reduction via genetic improvement. Literature. Acidification is mainly due to the action of an endogenous lipase of the fruit's mesocarp, but it can also be caused by microbial lipase or autocatalytic hydrolysis. Many factors, particularly plant material, conditions of harvest and post-harvest bunch treatment, and conditions of oil extraction and storage have an appreciable impact on acidification. Acidification reduces the quality and market value of palm oil and causes important oil losses due to the removal of free fatty acids in the mill. The genetic background of individuals of low oil acidity has been identified. The variability of this trait makes varietal selection possible. One gene implicated in palm oil acidification has been identified, but other genes or genetic factors may also be involved. Conclusions. Such research has led to the recent commercialization of the first oil palms with low acidity. This will improve oil quality, increase yield and facilitate the management of harvest and post-harvest operations, especially for smallholder farmers. There is a need to identify all the genetic factors responsible for the degradation of triglycerides in the Elaeis genus. The validation of genomic tools would allow the marker-assisted selection of oil palm varieties with low acidity

Improving palm oil quality through identification and mapping of the lipase gene causing oil deterioration

The oil palm fruit mesocarp contains high lipase activity that increases free fatty acids and necessitates post-harvest inactivation by heat treatment of fruit bunches. Even before heat treatment the mesocarp lipase activity causes consequential oil losses and requires costly measures to limit free fatty acids quantities. Here we demonstrate that elite low-lipase lines yield oil with substantially less free fatty acids than standard genotypes, allowing more flexibility for post-harvest fruit processing and extended ripening for increased yields. We identify the lipase and its gene cosegregates with the low-/high-lipase trait, providing breeders a marker to rapidly identify potent elite genitors and introgress the trait into major cultivars. Overall, economic gains brought by wide adoption of this material could represent up to one billion dollars per year. Expected benefits concern all planters but are likely to be highest for African smallholders who would be more able to produce oil that meets international quality standards