It depends on many factors.  Starch is paracrystaline.  So, lack of birefringence is an indicator of gelatination.  You could make a slurry and observe under polarized light.  Compare this to standard flour.  If only 20% or less granules exhibit the polarization cross, it is considered gelatinized.

Thank you very much Claire Wills.

Which instrument do recommend for this test?

Are you aware of any other simpler technique?

Dear Mario Martinez Martinez,

Thank you very much for your assistance. I dont have access to DSC or RVA but have data on water absorption capacity. Is there a threshold WAC that qualifies a sample sample of flour to consist mainly of pregelatinized starch?

Dear Mario Martinez Martinez, 

Thanks again for your valuable contribution.

Regards.....