Why does extraction change the components especially within an oil or hydrosol? There are many catch phrases aside from organic, pure, and therapeutic grade to look out for. Cold pressed oils are typically top quality. Why? Heat can chemically change the components and benefits of an oil. Related specifically to oil extraction excessive heat can strip the oil of it's benefits, losing key active properties.
Hydrosols at their purest form are steam distilled. The finished production becomes present in precipitated water. Many people are familiar with witch hazel because it is easily available, but it is most commonly distilled from alcohol. With this component it becomes extremely drying and the incredible active properties are diluted and the composition is no longer as effective.
Why is the origin important? It's important to know where each ingredient thrives in its most natural environment. For example the same essential oil from Bulgaria will have different characteristics than that plant from Provence. Environmental conditions and soil can change a plant completely.
Knowledge regarding the characteristic traits is such useful information. When we were researching essential oils and carrier oils we learned this lesson the hard way. All products contained the first two qualifications, but lacked the proper characteristics and potency. It was a critical lesson to deepen our knowledge in order to provide only the most active, effective, and reliable products.