Using liquid smokes as food preservative
Liquid smokes have been used extensively in food systems to impart flavor characteristics that are similar to smoked food products. These may be used to preserve quality and ensure safety of foods.
Liquid smoke is traditionally applied to meats, fish and poultry and it has also been used to add flavor to items such as cheese, tofu and even pet foods.
It has been as an alternative process derived from the smoke treatment after the burn of sawdust or wood chips, followed by either the condensation or polymerization stages.
Liquid smokes are usually obtained from the condensation of wood smoke produced by smoldering wood chips or sawdust under limited oxygen. Commercial full-strength liquid smokes are commonly fractionated, purified and concentrated to yield aqueous, oil or dry powder products.
There are several methods for applying liquid smoke. Liquid smoke can be directly added to the meat batter, or dipping the product in to the liquid smoke solution, or by spraying the smoke solution over the product.
Improved hygiene, a decrease on processing time, lower environmental pollution and less smoke varieties, are among the advantages of such technology, obtaining products with distinct organoleptic characteristics with antimicrobial properties as well as the possibility to eliminate poly aromatic hydrocarbons – PAHS. The main health concern about PAH is due to the fact that some of them have proven to be highly carcinogenic in laboratory animals, having been also implicated in different types of human cancers due to a metabolic activation in mammalian cell to “dihydrodiol epoxides” causing errors in DNA replication.
Through the refining process, undesirable polycyclic aromatic hydrocarbons (PAH) are removed, and the intensity of flavor and color in the resulting refined liquid smoke is adjusted.
The various phenolic compounds present in liquid smoke lowers the pH and destroys the walls of bacterial cells.
The chemical composition of liquid smokes depends primarily on the wood type and moisture content of wood, the latter influences the pyrolysis temperature and the duration of smoke generation.
Use of liquid smoke is a more controllable and consistent process compared to traditional smoking practices. Liquid smoke includes either smoke condensate dissolved in water, oil or smoke extracts in organic solvents. Smoke condensate can also be absorbed on solids such as spices, salt, sugars, starch or protein, thus resulting in dry or powdered forms.
