Winterization, also commonly called “dewaxing,” is a refining process that removes undesirable plant waxes from botanical extract. If these waxes are not removed from the extract, then the final product can exhibit cloudiness, reduced potency, and off flavors. Winterized extracts are said to have longer shelf life than unwinterized extracts.
Winterization is a process that is common within the botanical extraction industry as well as in other industries. The edible oil industry, for example, winterizes Canola and other food oils to ensure their shelf stability and clarity. Cloudiness or haze in an edible oil would reduce its consumer appeal and would be damaging to sales. The biodiesel industry winterizes their fuel to ensure that the fuel flows well when it is cold out.
This depends upon the extraction technique and on the final product specifications.
Generally, processors will want to winterize their extract if their product specifications include any of the following:
The extraction technique plays a large role in determining the amount of wax that is present in the unrefined extract. Some extraction techniques produce extracts that are low enough in wax that they are considered “winterized” for most purposes without further refining. Other extraction techniques produce extracts that are super high in wax content, and that cannot be used for any purpose without dewaxing.
Listed below are the common extraction techniques and the generalized characteristics of each extract:
Winterization is a simple process. The basic steps are described briefly below:
There are several ways to winterize extract. The most common way, and the way that Aptia recommends, requires a winterization reactor, a stainless filter housing, and a solvent recovery apparatus.
The winterization reactor is a stainless steel jacketed tank that is mixed and that is cooled by an external refrigeration unit. The extract and the solvent are loaded into this vessel and they are mixed together into a solution. Then they are also cooled in this vessel. Aptia manufactures a series of reactors, ranging from 50 Liter / 15 Gallon capacity up to 660 Liter / 175 Gallon capacity, that are designed specifically for this purpose.
After the solution has been chilled in the reactor, it is sent through a filter housing to separate the waxes from the miscella. Aptia manufactures the DWF stainless filter housing specifically for the moderate scale filtration requirements that are so common in the hemp industry. Aptia can also provide larger equipment for larger filtration requirements.
The winterized miscella then needs to undergo solvent recovery to separate the winterized extract from the solvent. Aptia manufactures many solvent recovery systems to meet each different facility’s requirements.