Download SIP - Proteins from oil seedsremarks - 20150317

Proteins from oil seeds
(part of the research line Biorefinery of protein-rich biomass)
Background
Recovery of oil from fruit or oilseeds is mainly done by continuous screw pressing. In order to increase
the oil yield, seeds can be pre-treated by preconditioning. Often the pressing stage is followed by an
extraction step with organic solvents, water or supercritical fluids to recover the residual oil from the
press cakes. The oil production from rapeseed and sunflower seeds results in co-products that still
contain valuable compounds like proteins. The quality of the proteins and lipids in these co-products is
largely determined by the processing conditions. An important step in the processing of rapeseed is the
inactivation of enzymes like myrosinase and lipoxygenase. Enzyme activity of both enzymes lowers the
quality of the proteins and lipids due to the formation of unwanted compounds. The inactivation of
enzymes is done by heating which strongly reduces the solubility of the proteins and therewith the
functionality. In addition, it causes unwanted reactions of proteins with e.g. phenols, which lowers the
nutritional quality. The nutritional quality of the proteins is very important for food applications, for nonfood applications the functionality is of great importance whereas the nutritional quality is irrelevant.
Rapeseed proteins for non-food applications can be obtained from currently available press cake. For
food applications, however, a new process should be developed.
Rapeseed is the most important oilseed produced in the EU-28. The rapeseed meal consists mainly of
proteins (40-45%). Cruciferin (12S globulin) and napin (2S albumin) are the major proteins found in
rapeseed isolate. The animal feed market is the main outlet for these co-products. Since the European
production of oil (seeds) steadily increases, also the amount of press cakes increases to a current level
of about 14.1 Mtons rapeseed cake, 10 Mton soy cake and 4.5 Mtons sunflower cake1.
Intended effects
At TNO and DLO-FBR knowledge is available on extraction, purification and modification of proteins for
food, feed as well as non-food applications from several protein rich sources origins . This knowledge can
be further expanded by using side streams from protein rich press cakes. By using basic knowledge on
the properties of the proteins in rapeseed, optimised extraction procedures could be used to produce
protein rich fractions with divers compositions in protein content, protein distribution and other nonprotein compounds. This diversity can lead to optimised functionality for the applications that will be
investigated. Knowledge developed on large streams can also be applied to smaller streams of oil seeds,
like sunflower, linseed or cotton.
Research focus
TNO and DLO-FBR will combine their technology portfolios to investigate four research routes:
1. Redesign of the extraction of functional proteins (food) from rapeseed press cake
•
Dry fractionation of carbohydrates and proteins (air classification, electrostatic separation)
•
Use of new fluids (supersonic fluid feed, tailor made extractants)
•
Selective extraction conditions (extrusion-extraction, selective separation of proteins and/or
removal of anti-nutritional factors)
•
Use of several wet fractionation techniques, such as chromatography, ultra- and dia
filtration, to obtain specific fractions.
2. Adapted process for oil and protein isolation from rapeseed . Focus on oil removal with the goal to
optimise both oil and protein quality. In this research route the traditional hexane extraction used to
extract the remaining oil rest from partially defatted press cake should be avoided. Alternative
processing should be incorporated to isolate the proteins from partially defatted press cakes
3. Redesign of processing press cakes (sunflower and soy bean). Similar to adaptation of the process
for production of rapeseed oil and proteins, an adapted process could very well be successful for
other sources of oil rich seed like soy and sunflower.
1
http://ec.europa.eu/agriculture/cereals/presentations/cereals-oilseeds/market-situation-oilseeds_en.pdf
1
4.
Non-food protein derivatisation towards adhesives, binders, surfactants and building blocks.
Protein properties can be tailored toward specific applications. For instance the surface activity and
water resistance of proteins can be adjusted from very low to very high. Preferably, modification
reactions are used which can be applied at a large scale, at low costs, and with the use of (chlorinefree) reactants which are used routinely in the chemical industry. Since proteins are built up by
many different reactive amino acids (amino, carboxylic, hydroxyl, amide), there are many
possibilities to adjust the functional properties of a protein. Here, four routes will be mentioned.
Hydrophilization (to increase protein solubility in water)
Partial hydrolysis (to increases protein solubility in water
Hydrophobization (to increase dispersability in non-solvents, (including water).
Crosslinking (to improve water resistance and mechanical strength)
Duration/planning
The project will initially have a duration of 2 years; the period for which funding from EZ for TNO and
FBR is available. Both TNO and FBR strive to continue the project after this period.
Invitation to Industrial Partners
Industrial parties interested and able to act as suppliers or converters of (sidestream) proteins, potential
producers and users of protein derived products, are invited to join the project.
2