For the fisherman with his own smokehouse in the backyard or the barbecue fanatic who wakes up at 2 am to fire up the smoker for that perfect 14-hour smoked brisket, the idea that someone could pop open a little bottle and pour in some smoke seems like blasphemy. In part, this is where Liquid Smoke gets its bad reputation. Stories emerge about strange chemicals, toxic substance, and the kind of chemistry that would turn you into a super villain if we all lived in the Marvel Universe.
This simply isn't true.
The real story starts with Ernest H. Wright, who at the age of 15 noticed a black liquid dripping from the stove pipe that heated the print shop he worked in. This black liquid tasted like smoke. Years later, as the owner of a drug store, he experimented with wood combustion and found that by condensing the hot smoke from a fire it would form a smoke-flavored liquid. After a few years of working to stabilize the flavor, he perfected the process, and in 1985 introduced Wright's Liquid Smoke, which is still sold today.
Liquid Smoke is really as simple as all this makes it sound. Wood gets burned, the exhaust of that fire is a lot of things to a chemist, but to most of us, it is smoke and steam. Fire produces water in the form of vapor and this vapor, condensed through a cooled tubing, captures the smoke. Take this liquid and distil it down to a concentrate, filter out the impurities (soot and ash) and you have liquid smoke.
So "all natural" liquid smoke is, in fact, all natural. No strange chemistry, just smoke suspended in water. But, a true devotee of barbecue or smoked foods would never touch the stuff, right? The truth is, most of the liquid smoke manufactured in the world doesn't find its way into those little bottles on the grocery shelf.
Liquid smoke is used as a flavor additive in a whole host of foods. It is, of course, the source of the smoky flavor in commercial barbecue sauces, marinades, and "barbecue" flavored foods. Liquid smoke is also in hot dogs, smoked meats in the lunch aisle, and a number of cheeses. It is also used in most of the bacon you buy.
Since pure liquid smoke is considered natural by the government it can be applied to foods labeled as natural without any real disclosure. The label on the bottle of most brands of liquid smoke will say that the ingredients are water and some kind of smoke, like "hickory smoke". This little loophole in labeling allows bacon makers to say that their product is smoked, list smoke as an ingredient, and never say that it is made with liquid smoke and never spend a moment in an actual smoker.
While barbecue snobs turn up their noses at liquid smoke, the truth is that most of them probably consume quite a bit of the stuff without even realizing it. Producers of these foods can call their products smoked gouda or smoked sausage and never actually smoke anything in the way we think. The process of adding liquid smoke or other smoke flavorings becomes the justification for the use of the word "smoked".
So, should you use liquid smoke? I'm not going to say no. Liquid smoke is as safe as any smoking process, probably more so. This means that there is a very small, but real cancer risk. This is because smoke, no matter the source, contains a number of interesting chemicals and some of them have been shown to cause cancer. According to studies, these chemicals can be found in liquid smoke.
If you do use liquid smoke to add that certain smokiness to your pot of chili, I suggest choosing a brand that contains no additional flavorings. If the point is to add smoke flavor, I don't see the reason to add molasses or any other flavorings in the process.
There are alternatives, however. These days it is possible to find smoked salts, sugars, and other foods that are in fact actually smoked. Buy from reputable stores that specialize in natural products and there should be any concern about buying salt coated in liquid smoke.