'desirable amount' is correct and usable in written English.
You can use it when you want to refer to a quantity of something that is significantly large enough to be considered desirable. For example: Winning the lottery would result in a desirable amount of money.
And don't bother with the newest "debate," about the properly desirable amount of "reality" that American fiction should currently possess.
For an upper limit, the panel set 5.8 grams of salt a day (a little more than one teaspoon), but noted that this was not a desirable amount.
To find places to invest this money it has had to diversify into areas in which this erstwhile value investor lacks the desirable amount of expertise.
This paper experimentally investigates the desirable amount of ZnO particles filled into HGFs and their interval inside a composite to maximize its UV absorbability.
Steel fibres can be used either as the only shear reinforcement or in combination with a minimum or a desirable amount of stirrups.
Desirable amount of SR101 (Sigma-Aldrich, München, Germany) was firstly dissolved in 300 μl ethanol.
Overall, sitting was more strongly associated with unhealthy troponin levels than exercise was with desirable amounts.
The FAME profile had desirable amounts of saturated (32.81%), monounsaturated (36.41%), polyunsaturated (30.59%) methyl esters.
Selecting the desirable amounts of adsorbent is a key parameter which obviously affects the whole removal procedure.
Therefore, a compromise must be made to achieve desirable amounts of genetic gain without increasing inbreeding too much.
It is highly desirable that the amount of the debt should not be increased beyond the limits which will be regarded everywhere as safe under all circumstances.
