Objectives
- Produce a whole flaxseed that is substantially degummed and free of cyanogenic glycosides.
- Produce a whole flaxseed that is largely depleted in heavy metals.
- Produce a flaxseed gum powder that is substantially free of metals and cyanogenic glycosides.
- Produce flavoured flaxseed products that are a dietary source of omega three fatty acids, protein, and lignan.
Project Decsription
Flax seeds contain compounds that include cadmium, and cyanogenic glycosides both of which reduce the nutritious effect of the flax seed. The concentration of these compounds is regulated and disqualifies Canadian flax seed in European and Japanese markets. We have invented a process that reduces the cadmium content by 85%, and eliminates the glycosides from whole flax seed, making it eligible for previously inaccessible markets. The seed treatment consists of steeping in dilute, edible acid for 2-24 h, followed by degumming and drying. The degumming process was optimized up to 80 L/h using 3-4 washes with water and is readily scalable. Stirring the seed-water mixture helps to reduce the amount of water and time needed. Additives such as enzymes, acid, or use of sonication do not improve the degumming efficiency in time or water use. The seed and gum fractions may be dried in a forced-air dryer with low breakage. It is not recommended to use a Morridge auger as it may clog and cause seed breakage. The seed fraction was analyzed for cadmium using Inductively Coupled Plasma Mass Spectrometry at the SRC Environmental Analytical Laboratories. The seed and gum fractions were analyzed for cyanogenic glycoside using proton nuclear magnetic spectroscopy (1H-NMR) conducted at the Saskatchewan Structural Sciences Center, and gas chromatography in the Reaney lab. The dried degummed seed was roasted using an oven, fluid bed drier, or microwave. The resulting roasted seed product had flavor similar to that of other roasted oilseed. This demonstrates its suitability as a baking ingredient and food product. The gum fraction is also suitable as an egg replacement and has properties comparable to xanthan gum as a thickening and texturizing ingredient. Flax seed and gum food products developed under this grant are available at Prairie Tide Diversified Inc. and some have been registered as natural food products.
Grower Benefits
- Whole flax seed treatment using dilute, edible acids eliminates cyanogenic glycosides in 2-24 h, an reduces cadmium content by 85% in 24 h.
- Flax seed degumming and drying process was optimized using an automatic sieve and forced-air dryer.
- The gum fraction co-produced in this process is also free of cadmium and cyanogenic glycoside.
- The seed fraction may be roasted to produce a pleasant flavour comparable to other oilseed like sesame.
- This new process qualifies flax seed for previously inaccessible markets in Europe and Japan, and produces food ingredients for texture, flavour, mucilage, and egg replacement.
