While trappers and hunters have used various scents for years to mask human odor and attract their target animals, fishermen have used these devices too. Some articles I have read get quite technical as to ingredients and why and how they work. I have concluded, after much reading, that scent used on bait and lures does both. Many products are commercially made and available but being a DIY type of person about some things, I also concluded that I can make my own and I have.
Around our house it is called "stink". I have variously used mineral oil which is the same as unscented baby oil, glycerin (both available at your local drug store), water, cod liver oil, fish oil capsules (cut them open and remove the oil as the capsules will not dissolve), garlic powder, garlic salt, anise extract, coffee and a few other ingredients too.
I first started by taking a pint jar filled half full of water and set it in a small pan of water which I brought to a boil on the stove. I did this as I figured the jar would be easier to clean than the pan. I added a small spoon full each of garlic powder and garlic salt to the heated water in the jar and stirred a bit to get them to dissolve. The garlic salt dissolves but the garlic powder does not. I then poured mineral oil in the jar filling it up and stirring it around a bit more and then poured the entire contents into a plastic bottle commonly used to dispense ketchup, mustard, etc., and usually found in grocery stores in the housewares section. I added a few drops of food coloring, several dashes of "glitter" of the kind used in cake decorating, stirred some more to get all the ingredients mixed well and set it aside.
Well, you may have guessed it. Oil and water do not mix and the garlic powder settles in the bottom of the container along with the glitter. No problem. It is just like some salad dressings that must be shook up prior to use. I used this same basic recipe and also used actual garlic cloves cut up in small pieces with a piece or two added to the container. I have also used coffee grounds, a drop or two of anise extract...it doesn't take much and it is an ingredient found in many commercially made scent formulations. I ended up with six different combination s of ingredients with water and mineral oil or mineral oil by itself as a base.
Next, I did the same thing using half glycerin and water for the base and glycerin by itself in an attempt to thicken the water as my trials trying to do so with corn starch failed. I also made up a cod liver oil and garlic formula and a half cod liver oil and half glycerin as a base. The cod liver oil and glycerin tend to separate and require shaking prior to use. I eventually obtained a small supply of 2 ounce bottles with spouts and caps and transferred some of all the recipes into these bottles for ease of taking along on my fishing trips. A few drops of scent on a bait or lure is sufficient.
Do they work? Who knows. I have caught fish using my razzu scent/attractants and I have been skunked too. That brings up the point about raising a stink. WARNING and DISCLAIMER! Brewing this stuff in your house and especially in your kitchen may be hazardous to your domestic tranquility...it stinks! But no more than that delicious garlic dip your wife makes that you relish with chips or crackers...that stuff stinks too.