How to increase wheat starch content

When wheat is destined for biofuel production, the yield of ethanol is a key component to consider. Varietal choice is an important consideration with those that are soft wheat types tending to give higher ethanol yields. Harvesting delays must be avoided as there is a danger that grain in the ear starts to grow (sprout) at which point enzymes begin to breakdown the starch.

Nitrogen effects on grain starch content

Nitrogen is the most important nutrient that will directly affect the grains starch content.

High ethanol content is inversely related to grain nitrogen i.e. low grain nitrogen (or protein) is an indication of high starch content, and hence potentially high bioethanol yield per tonne. If the grain is grown specifically for ethanol then nutrient management practices should be adjusted accordingly. Nitrogen should be applied early in the growing season preventing any late nitrogen applications to increase grain protein content.

Low protein wheat grain has the highest alcohol yield for ethanol production

The correlation of wheat grain starch and grain protein