Barley with very low levels of hordeins
The present invention relates to methods of producing a food or malt-based beverage suitable for consumption by a subject with Coeliac's disease. In particular, the present invention relates to methods of producing a food or malt-based beverage with very low levels of hordeins. Also provided are barley plants which produce grain that can be used in the methods of the invention.
1. A method of producing a food or malt-based beverage ingredient, or a food or a malt-based beverage, from barley grain comprising 50 ppm or less hordeins, the method comprising:
(i) processing barley grain comprising 50 ppm or less hordeins to produce malt, wort, flour or wholemeal, and/or
(ii) mixing barley grain comprising 50 ppm or less hordeins, or malt, wort, flour or wholemeal produced from said grain, with at least one other food or beverage ingredient,
wherein:
a) the barley grain is homozygous for a genetic variation of the Hor2 locus where most or all of the B-hordein encoding genes in the Hor2 locus have been deleted relative to the Hor2 locus of wild-type barley grain, or wherein the malt, wort, flour or wholemeal produced from said grain comprises DNA which comprises the genetic variation of the Hor2 locus where most or all of the B-hordein encoding genes in the Hor2 locus have been deleted relative to the Hor2 locus of wild-type barley grain,
b) the barley grain is homozygous for a genetic variation at the Hor3 locus of barley which results in the grain lacking D-Hordein, or wherein the malt, wort, flour or wholemeal produced from said grain comprises DNA which comprises the genetic variation at the Hor3 locus of barley which results in the grain lacking D-hordein, and
c) the barley grain is homozygous for a genetic variation at the Lys3 locus of barley which results in the grain lacking C-hordeins, or wherein the malt, wort, flour or wholemeal produced from said grain comprises DNA which comprises the genetic variation at the Lys3 locus which results in the grain lacking C-hordeins,
thereby producing the food or malt-based beverage ingredient, or food or malt-based beverage.
2. The method of claim 1 , wherein the grain,
malt, wort, flour or wholemeal comprises 20 ppm or less hordeins.
3. The method of claim 1 , wherein the average weight of the grain is at least 35 mg.
4. The method according to claim 1 , wherein at least 80% of the grain do not pass through a 2.8 mm sieve.
5. The method according to claim 1 , wherein the grain is from a plant which has a harvest index of about 40% to about 60%.
6. The method according to claim 1 , wherein the grain has a length to thickness ratio of less than 5.
7. The method according to claim 1 , wherein the flour or wholemeal produced from the grain comprises 10 ppm or less hordeins.
8. The method according to claim 1 , wherein the grain, or malt, wort, flour or wholemeal produced from said grain lacks:
i) B-hordeins comprising a sequence of amino acids provided as SEQ ID NO:53, and
ii) B-hordeins comprising a sequence of amino acids provided as SEQ ID NO:54.
9. The method according to claim 1 , wherein the genetic variation at the Hor3 locus of barley which results in the grain lacking D-Hordein is a null allele of the gene encoding D-hordein which comprises a stop codon, splice site mutation, frame-shift mutation, insertion, deletion or encoding a truncated D-hordein, or where most or all of the D-hordein encoding gene has been deleted.
10. The method according to claim 1 , wherein the grain, malt, wort, flour or wholemeal comprises 1% or less, of the level of hordeins when compared to grain from a corresponding wild-type barley plant or malt, wort, flour or wholemeal produced in the same manner from grain from a corresponding wild-type barley plant.
11. The method according to claim 1 , wherein the coeliac toxicity of flour produced from the grain is less than about 5% of flour produced from grain of a corresponding wild-type barley plant.
12. The method according to claim 1 , wherein at least 50% of the grain germinates within 3 days following imbibition.
13. The method according to claim 1 , wherein the food ingredient or malt-based beverage ingredient is flour, starch, malt, or wort, or wherein the food is leavened or unleavened breads, pasta, noodles, breakfast cereals, snack foods, cakes, pastries or foods containing flour-based sauces.
14. The method according to claim 1 , wherein the malt-based beverage is beer or whiskey.
15. The method according to claim 1 , wherein following consumption of the food or drink at least one symptom of coeliac's disease is not developed by a subject with said disease.
16. A barley grain comprising about 50 ppm or less hordeins, or a barley plant which produces grain comprising about 50 ppm or less hordeins, wherein:
a) the grain is homozygous for a genetic variation of the Hor2 locus where most or all of the B-hordein encoding genes in the Hor2 locus have been deleted relative to the Hor2 locus of wild-type barley grain,
b) the grain is homozygous for a genetic variation at the Hor3 locus which results in the grain lacking D-hordeins, and
c) the grain is homozygous for a genetic variationat the Lys3 locus of barley which results in the grain lacking C-hordeins.
17. A method of producing barley grain comprising about 50 ppm or less hordeins, the method comprising;
a) growing a barley plant of claim 16 , and
b) harvesting the grain of the barley plant.
18. The method of claim 1 , wherein the barley grain, or malt, wort, flour or wholemeal produced from said grain, further has a level of less than 2% of a wild-type level of γ-hordeins comprising a sequence of amino acids provided as SEQ ID NO:57, wherein the level of less than 2% is relative to a wild-type barley grain, or malt, wort, flour or wholemeal produced from said grain, of the barley variety Bomi, Sloop, Baudin, Yagan, Hindmarsh, or Commander.