Improved enrichment of vitamin d3 in transformed coleopteran larvae by a method of ultraviolet treatment and associated food powder

A method for preparing a beetle powder comprising:

• a light treatment step during which at least one light source emits ultraviolet rays of at least the UVB type in the direction of beetle larvae, wherein the ultraviolet rays of the UVB type have an irradiance at the beetle powder greater than 80 μW/cm2 and in that said beetle larvae are dehydrated at a temperature of between 40 and 250° C., preferably between 50 and 150° C., so that the slaughtered larvae have:
• between 2 and 15% water, more preferably between 3 and 8% water, and/or
• an activity of water (AW) of less than 0.7 and are optionally ground before said light treatment.