are no standards of identity, prescribed production methods, or tests which distinguish between liquid smoke and pyroligneous acid; they can be considered to be the same. However, the numerous variables that are manipulated during pyrolysis do lead to a wide range of compositions of the condensates. In addition, implementation of many further processing steps by concentration, dilution, distillation, extraction, and use of food additives has led to the many hundreds of unique products on the market worldwide. Wood, particularly hardwood, is by far the most widely used biomass pyrolyzed to make liquid smoke. Commercial products are made using both batch and continuous methods. Commercial products are made using a range of reactors from rotary calciners, heated screws, batch charcoal kilns, to fast pyrolysis reactors. The process type and conditions of processing lead to greater variances between the condensates than the differences between the common wood types that are in use. Variables such as feed rate, vapor residence time, particle size, oxygen infiltration, and temperature can have substantial effects on yield and composition of the condensates. Wide ranges of chemical composition are reported throughout the literature and unless the process and conditions are cited, there is limited utility of such results. Commercial manufacturers strive to control their manufacturing variables in order to standardize product compositions. Water is added either during condensation or after to cause separation of three fractions. Once water is added, the aqueous phase becomes the largest and most useful fraction. It contains wood derived chemical compounds of higher chemical polarity such as those found in carboxylic acid, aldehyde, and phenol chemical classes. Many compounds together are responsible for the flavor, browning, antioxidant, and antimicrobial effects of smoke and liquid smoke. The smallest condensed fraction is the lowest-polarity upper phase which a mix of phytosterols and other oily, waxy substances. The lower phase is commonly referred to as tar. It is an intermediate-polarity mixture of phenolic polymers, secondary and tertiary reaction products, some of the water-soluble polar compounds partitioned in the amount of which is governed by individual partition coefficients, water and the bulk of the polycyclic aromatic hydrocarbons. Wood tar has been used as a preservative, water repellent, and antiseptic. Tar from birch was produced as a commodity product on large scale in northern Europe. Today commercial liquid smoke products are still prepared from this phase. Liquid smoke condensates are made commercially for the global meat industry in