I think it does, but it is not a common method of solid or moisture content analysis. It may take longer time. I believe it will give you accurate data. In the process of freeze-drying the moisture is first frozen in to ice and then directly converted to vapor (sublimation) and escapes due to a negative pressure. Freeze-drying is the way of getting high quality dry solids as there is no heat damages and volatile losses as in conventional heating.  

I think one of the most common and accepted method is the oven drying method (ISO6731:2010/IDF 21:2010). In my opinion the freeze drying method is not the best, because not all water content can be vapoured away from the sample.

Dear Negin Neinavaie,

Freeze-drying is expensive and takes some time and was born  to preserve compounds in fruits and vegetables or other food products  such as flavonoids. Oven drying is a good choice.

Best regards

Aly R Abdel-Moemin

Of course, this method has high accuracy, however, is very expensive to use for this purpose method. You have to take into account the large amount of water present in milk.

For several reasons freeze drying is not seen as an analytical methodology, why use it if we have standards using simple procedures for the purpose? I think the best way is the use of the ISO/IDF standard.

Dear   Negin Neinavaie

please check pdf

I actually tried both vacuum oven drying and freeze drying, surprisingly the freeze drying method shows more water content rather than vacuum oven drying. what would be the reason?

What 's the difference in absolute value? For what purpose you are using the freeze-drying method?

To estimate total solid content. I found about 2-3% difference between two methods.