My yeast starters take about 12 hours and i make them in a 2L soda bottle
I take out some must pre-sweetening - provided its a fruit wine/mead/etc
And take out some must post-sweetening
About a pint-quart of each
I use Go-Ferm so i have to mix that in with 110F water, then let that cool down to the point where it wont kill the yeast... Add the yeast and let it sit for the 15 minutes that it states on the pack, to rehydrate
From there, i swirl in the yeast thoroughly & pour in a measuring cup or maybe a little more, of the pre-sweetened juice & let the yeast chew on that for an hour or two before adding in the "other half" (usually) and giving it a few more hours to chew through that.. Then i'll start adding the sweetened must every couple hours until its al added
The idea is to acclimate the yeast to A) being rehydrated & B) to the conditions in the must. By starting the yeast in water, relatively neutral & slowing increasing the amounts of sugar/acid added, the yeast have a gentler introduction to the must conditions than if you were to just sprinkle on top of the must and let 'er rip