What is the recommended time for letting Meat Taint for bait making muskrat if that makes a difference

I grind the meat 2x then place in a vented clean bucket about 1/2 full(to allow for exspansion) and the length of time depends on how hard you want the taint i like to keep it at least room temp for at least 4 to 6 weeks or until the top has a greyish/green crust
but when you peal that back its still pink underneath i let it go until it has a sour almost sweet twang to it then mix it all together and stabilize but allow it to stay in the vented bucket for a while to allow your preserving
ingredients to work and your bait to stop giving off gasses and stablilize before you place in smaller jars

It really depends on what type of aroma you want to achieve. A heavier taint, light taint, and even meat preserved fresh can all be effective depending on the application.

How the meat is tainted makes a big difference. Sun tainting will move fast, sometimes in just a few days before you start noticing a change. Aging in a cool, dark place is much slower and more controlled. I personally prefer to fine grind the meat into a paste first, then let it develop a light taint in about 1 to 2 weeks, kept out of direct sunlight. I taint mine in glass gallon jars with burp lids so I can see the entire product and allow the gasses to escape.

Regardless of the method, the best thing you can do is go by your nose. Check it every day until it reaches the aroma you are looking. Be sure to keep good notes on what you're tainting and roughly how long it took to get the product you wanted.

Keep in mind after you stop it with preservatives it will be more mild than you thought it would be. Personally in general the more I test formulations the more I lean towards a heavy taint for coyotes. In general it just seems to give off more odor, odor lasts longer and has more attraction. There are times and places for lighter taint but in general the heavier taint works best.

What you think and how it smells to you means nothing to the coyote, testing has showed me.

As Yes Sir says, be aware that after you stop it, the preservatives will stop the outgassing and it will become quite a bit milder odor. Depending on what you want for a finished product on how much taint you want. If you really want something load, put your meat in a bucket or jar, half full and just cover with water and leave it out in the sun over the summer (vented). You will be able to smell it just from the venting for quite a distance and when you take the lid off the odor will be strong enough to dent a fender. I've used "bait" prepared that way and left up to three years wilhout preserving for making call stations. It can be as loud as loud skunk. Be aware that the louder the taint is, the more of a rolling response it will create, so apply and set accordingly.