It's also going to depend upon which sort of minor scale you choose since there are three basic minor scales (in Western European music anyway, before we start getting into bizarre combinations of minor pentatonic, etc, etc): Natural minor, Harmonic minor and Melodic minor.
Natural minor is the easiest as it's simply any major scale shifted down three note names; eg, take D major but start playing it from the B. This makes the major triads in a Natural minor scale appear at the 3rd, 6th and 7th degrees (staying with the b minor for now: 3rd = D major, 6th = G major 7th = A major)
The Harmonic minor is only one note different from the Natural as it contains the raised 7th. This now makes the triad built on the 3rd degree an augmented triad, not major. Instead, the Major chords in a Harmonic minor will now only occur at the 5th and 6th degrees (in b minor, 5th = F# major, 6th = G major)
The Melodic minor scale can be confusing because it's going to depend on what the composer has done with his/her melody. This is the one that has the 6th and 7th degrees raised on the way up, and then lowered on the way down. So as a general rule, if the melody was ascending, the 6th or 7th were often raised and if it was descending, they tended to be lowered. The result of this is this it alters your choices of the availability of major triads within a minor scale.
Melodic minor
ascending gives you major triads at only the 4th and 5th degrees (in a minor, 4th = E major, 5th = F# major)
Melodic minor
descending (same as Natural minor descending): 3rd = D major, 6th = G major, 7th = A major
That's probably annoyed you now hasn't it?!