If you're referring to the the sudden shift in vocal registers that happens in lower masculine-type voices, this is most noticeable as a jump from chest voice to falsetto. If the voicebank you're using has falsetto recordings, or if you're able to use a strong bank together with a soft bank, you can put those notes right next to each other to make the tone shift very noticeable.
If the voicebank doesn't have multiple recorded expressions, you can simulate the tone difference using flags. For example, with moresampler, you might want to use Mt+(number) for the stronger note, and Mt-(number) and Mb+(number) for the weaker, breathier note.
If you're instead referring to vocal fry, a crackly tone that's often used at the beginning of phrases in emotional singing styles, the ideal method will of course still be to use a voicebank with dedicated vocal fry samples. Alternatively, you can experiment with notes that start slightly early, and with a pitchbend that starts from an extremely low pitch.