A continuum of research projects to improve extraction of oil and proteins in oilseed plants

Interest for vegetable oil is growing, especiallywith the increasing demandon fossil oil substitutes. World oil production is close to 135Mt with palm, soybean and rapeseed oils representing 31%, 24% and 15% respectively. In Europe, rapeseed is the major source of oil (69%). Most of this production is devoted to food uses, followed by emerging uses of oil as bio fuels, and to a lesser extent, as chemicals (250.000 t oil for EU in 2007). Seeds from rape, amajor European oil crop (>20,2Mt in 2007) contain around 45% (w/w) oil and 17 to 25% protein depending on the variety considered. Rapeseed oil has a low saturated fatty acid content and is rich in alpha linolenic acid (ALA, omega-3). It is thus one of the few foods which significantly contribute to the increase of omega-3 fatty acids in diets, by providing ALA. The two main valuable protein fractions in rapeseed meal are seed storage proteins: the 2S albumin-type Abstract: A key challenge in the actual context of fossil sources rarefaction, global warming, and of increase of the world global population, is to promote the use of molecules derived from renewable sources such as plants. Among these molecules, lipids and proteins are targets of interest. Plant lipids from oilseeds are attractive substitutes to the use of fossil oil. Till the beginning of the 20 century, numerous products used in the daily life were derived from natural renewable products. For instance, plant oil was commonly used as fuel for vehicles and was entering in the composition of paintings, lubricants etc. Unfortunately, natural oils have been progressively replaced by cheaper fossil oil in the fabrication of these products. Nowadays, fossil oils are becoming increasingly expensive being a finite comodity. It is thus important to reduce our dependence from fossil oil and develop substitution industries. Oilseeds contain important amounts of proteins which are mainly used in feed. As several kilograms of plant protein are needed to obtain one kilogram of animal protein, the interest toward using plant protein in food is reinforced. The developments of the use of plant lipids, as well as proteins are a major stakes for the competitiveness of European agriculture and industry, as well as for sustainable development. Extraction of oil and proteins from rapeseed has a significant cost, in term of energy and solvent uses, and finally affects the ultimate quality of the products (protein digestibility). In order to quantitatively extract seed reserves under mild conditions, it will be necessary to limit the amount of energy needed, and avoid any use of solvents. Ideally, seeds should be processed in a bio refinery. In this paper, we will describe how oilseeds store their reserves, and roadblocks for improving actual oilseed extraction processes. A continuum of research projects aimed at answering targeted questions will be presented, with selected results obtained.