Monday, September 9, 2013

OIL: cold pressed, expeller pressed, & chemical extractions

Information below brought to you by Recherch'e Organics:


OILS: 


We have all heard the terms cold pressed, expeller pressed and chemical extractions used in conjunction with the oils we buy.  What do all of these terms mean? Which are healthy and to what degree? In these next few paragraphs I am going to try and break down just what is going on in each individual process.  If you have read any of my other numerous posts about individual oils, these terms should be at least somewhat familiar (if only by sight). 


Expeller Pressing Oils:
     Expeller Pressed Oils:
An expeller pressed oil is an oil that has come about by means of chemical free, mechanical or physical methods.  The raw material (usually nuts, seeds and occasionally algea) is pressed, squeezed, and or crushed under high pressure until oil begins to seep out from the "parent material".  This is the method that oil has been extracted for centuries world wide. The temperature reached during this crushing and pressing process often depends on the hardness of the object being crushed. The harder the seed/nut the more friction, thus heat, is created. There is no external heat added in expeller pressed oils only what is generated by the friction of material being pressed.  Expeller pressing will only remove approximately 65-70% of the oil within the raw material, often being seen as a down fall to this method of extraction.
Cold Pressed:
 Cold pressed oils are a form of expeller pressed oils.  These oils follow the same guidelines of no chemicals used in the process and extracted only by mechanical or physical means.  The difference being, that Cold Pressed oils can not be brought to a temperature over 120 degrees F (approx. 49 degrees C).  This method preserves all of the delicate phytochemicals that make the nut or seed oil truly beneficial. All of the nuances of flavor (if using for cooking) are preserved, nutritional values, color, natural odor are all held intact. It is important to note that Europe has rigorous standards in place when it comes to using the words "cold processed" with oils.  California is another place the upholds the value of the wording in labeling, however not all places are as stringent as the two above mentioned places.  It is wise to know where your oils are coming from and look into the companies "policies" about their product.  
Expeller Pressed Oils

Chemical Extraction and Conventional Methods of Oil Extraction:
Solvent or Chemical extraction methods are by far the most popular oil rendering method of today.  Often a chemical called hexane is used in this process, which is known as a toxic substance.  Other chemicals often used are heptane, octane, or pentane, all four of which are types of naptha or petroleum distillates.   This chemical method has found it's popularity by how inexpensive and time efficient it is.  Using hexane and other chemical solvents allows a company to recover about 99% of the oil from the parent material.  In order to rid the oil of hexane, it is heated to very high temperatures, thus destroying most or all of the beneficial constituents naturally occurring with in the oil.  Not only are the natural beneficial properties of the individual oil destroyed but trace amounts of the chemical are allowable with in the food grade oil.


REMEMBER: 
Your skin is the largest organ of your body! What you put on the outside will certainly have effect on the internal workings and health and well being of the rest of your organs.