Red beet pigment composition
A method for obtaining a betalain pigment composition from red beet plants comprising pre-harvest foliar spraying of an ethylene-generating compound and the use of the obtained betalain pigment composition for coloring of an edible product.
1. A method for obtaining a betalain pigment composition from red beet plants, comprising:
(i) foliar spraying red beet plants with an ethylene-generating compound;
(ii) harvesting the red beet plants sprayed in step (i); and
(iii) isolating betalains from the red beet plants harvested in step (ii), thereby obtaining the betalain pigment composition.
2. The method according to claim 1 , wherein the ethylene-generating compound is one or more selected from 2-chloroethylphosphonic acid; (2-chloroethyl)methylbis-(phenylmethoxy)silane; (2-chloroethyl)tris(2-methoxyethoxy)silane, and 1-amino-cyclopropane-1-carboxylic acid.
3. The method of claim 2 , wherein the ethylene-generating compound is 2-chloroethylphosphonic acid.
4. The method of claim 1 , wherein the betalain pigment composition comprises betanin and vulgaxanthin.
5. The method according to claim 4 , wherein the betalain pigment composition has a betanin to vulgaxanthin ratio increased by at least 5% as compared to a betalain pigment composition obtained by a comparison method without the use of ethylene-generating compound in step (i).
6. The method according to claim 1 , wherein step (ii) comprises isolating betalains of step (iii) from at least 100 different harvested red beet plants.
7. The method according claim 1 , wherein the betalain pigment composition has a betalain pigment content at least 5% (w/w) higher as compared to a betalain pigment composition obtained by a comparison method without the use of ethylene-generating compound in step (i).
8. The method according claim 1 , wherein the betalain pigment composition has a betalain to total soluble solids (TSS) ratio is increased by at least 5% as compared to a betalain pigment composition obtained by a comparison method without the use of ethylene-generating compound in step (i).
9. The method according to claim 1 , wherein the amount of ethylene-generating compound applied at each spraying in step (i) is from 20 g egc ha −1 to 5000 g egc ha −1 .
10. The method according to claim 1 , wherein the red beet plants are in a red beet crop and the total amount of ethylene-generating compound applied by spraying in step (i) on the red beet crop from sowing to harvest is from 50 g egc ha −1 to 10000 g egc ha −1 .
11. The method according to claim 1 , wherein the foliar spraying of ethylene-generating compound of step (i) is done later than 2 weeks after the red beet plants were planted.
12. The method according to claim 1 , wherein the foliar spraying of ethylene-generating compound of step (i) is done at least 3 times before the harvesting the red beet plants of step (ii), wherein harvesting of the red beet plants of step (ii) is done later than 6 weeks after the red beet plants were planted.