Method for removing glucosinolates from oilseed meals
A process to remove the glucosinolates of oilseed meals, such as Brassica carinata oilseed meals, is provided. In one embodiment, exogenous myrosinase is used to convert the glucosinolates to volatile isothiocyanate compounds, which can then be removed under conditions of mild heat and negative pressure. In another embodiment, heat and pressure are used to remove glucosinolates from Brassica carinata oilseed. The processed meals may contain less than 80% of their starting levels of glucosinolates and may be suitable for use in various applications, including as animal feeds.
1. A process for producing a meal fraction of Brassica carinata oilseed having reduced sinigrin content, the method comprising:
a. pressing seeds of Brassica carinata oilseed to produce oilseed flakes;
b. cooking the oilseed flakes at a temperature in the range of 105° C. to 180° C.;
c. pressing the cooked oilseed flakes to remove oil from the oilseed flakes, thereby producing an oil fraction and a meal fraction;
d. treating the meal fraction with hexane to extract residual oil;
e. desolventizing-toasting the hexane-extracted meal fraction to remove residual hexane for a period of greater than 1 hour but less than 5 hours; and
f. drying the meal fraction to a moisture content of 12% or less, and
g. recovering a meal fraction of Brassica carinata having a sinigrin content of less than 20 μmol per gram of meal.
2. The process of claim 1 , wherein the sinigrin content of the meal fraction of Brassica carinata oilseed is less than 15 μmol per g of meal.
3. The process of claim 1 , comprising cooking the oilseed flakes at a temperature in the range of 105° C. to 150° C.
4. The process of claim 1 , comprising pressing the cooked oilseed flakes with an expeller or screw press.
5. The process of claim 1 , comprising desolventizing-toasting the hexane-extracted meal fraction at a temperature in the range of 95° C. to 115° C.
6. A meal fraction of Brassica carinata oilseed produced by the process of claim 1 .
7. A meal fraction of Brassica carinata oilseed produced by the process of claim 2 .
8. A meal fraction of Brassica carinata oilseed produced by the process of claim 3 .
9. A meal fraction of Brassica carinata oilseed produced by the process of claim 4 .
10. A meal fraction of Brassica carinata oilseed produced by the process of claim 5 .