"An oil is any neutral, non-polar chemical substance that is a viscous liquid at room temperatures and is both hydrophobic (does not mix with water, literally "water fearing") and lipophilic (mixes well with other oils, literally "fat loving")."
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Butters vs. Oils
The right term for what we call "butters" is "fats" - Physically, oils are liquid at room temperature, and fats are solid. Chemically, both fats and oils are composed of triglycerides.
Some vendors sell the "butter" version of some oils, those are just a blend, mostly a mix of Shea butter and the oil advertised. Oils and Butters come in just one form, what gives them the texture they have is their chemical composition, we can't "magically" turn an oil into a butter or vice-versa.
In my shop you will find Tucuma butter and Tucuma oil - the butter comes from the seeds and the oil comes from the pulp of the tucuma fruit, they are two different products chemically and physically.
Essential vs. Carrier Oils
Carrier Oils or base oils - characteristically, carrier oils are rather bland and viscous (thick in consistency), with little to no aroma. The good quality ones are mechanically extracted from fruits, seeds and nuts (take a look at "cold processing").
Essential Oils or volatile oils are aromatic and derived directly from various plants through a distillation process. The distillation process is usually with water or steam and makes use of the petals, leaves, bark, stem, and even roots of various plants. Essential oils are not fragrances or perfumes.
Mineral, Vegetable or Animal
Oils can come from 3 sources: Mineral - a distilled from petroleum, Animal - extracted from animal fat tissues and Vegetable, extracted from plants, most commonly the seeds and nuts but also from leaves and pulps of some plants.
Expeller pressed vs. Solvent Extracted Vegetable Oils
Oils and butters can be extracted mechanically, by a presser, the ideal way of extracting them is mechanically under controlled temperature. When mechanically extracting an oil, the friction generates heat, the harder the part of the plant is being pressed, the more heat it produces. In order not to change the oil's properties, this process is done inside cold rooms resulting in the products we call "cold pressed".
There are no chemical residues in oil that has been expeller pressed resulting in a cleaner, more pure oil, higher in natural colors and flavors.
Oils can also be extracted chemically, which is easier, cheaper and extracts more oil but produces an oil extremely inferior in quality and that can still carry microscopic particles of chemicals.
Unfortunately mass market oils, however, are not required to be labeled as solvent extracted.
Refined vs. Unrefined Oils
An oil that has been refined has passed through a series of processes such as neutralizing (to remove FFA), bleaching (to remove color) and deodorizing (to remove odor and taste). These processes are done chemically and by high heat and besides leaving chemical particles behind, they also strip all the good properties from the oils.
Unfortunately big corporations need their products to look the same every time, they also want them to have very little taste, color and odor as these are also considered "impurities" by modern consumers (silly consumers), so refined oils are more popular than ever. There are two kinds of Refining:
Chemical Refining - the Vegetable Oil is treated with caustic lye for separation of free fatty acids from oil. This is a conventional process that can be applied to all oils. The waste-water from refinery requires extensive treatment, resuming - it creates a poor quality oil and leaves a mess behind.
Physical Refining - In Physical Refining, Vegetable Oil is subject to distillation to remove free fatty acids. This reduces the amount of waste water therefore pollution. This process is becoming more popular but it is also more time consuming and expensive resulting in a more expensive oil.
Unrefined Oils (also called Virgin, Extra-Virgin or "Raw") preserve their odor, taste and color, these can change depending on the producer, area and time of the year the oil is produced. Unrefined oils can also carry some impurities and can go rancid faster. But when comes to skin and hair care you should choose unrefined oils as they keep their medicinal and cosmetic properties intact. They may be more expensive and some of them may have a stronger scent, harder to mix with essential and fragrance oils. So it really depends on your goals for the final product.
We see all these health "buzzwords" everywhere, but what do they mean?
"Wild harvested" or "Wildcrafted" is the practice of collecting plants in the wilderness, on their natural habitat. They are not farmed therefore they are not modified in any way and usually do not have the presence of any chemicals. "Wild-harvest" is usually a "Sustainable" practice: generally only the fruit, flowers, seeds or branches from plants are taken and the living plant is left, or if it is necessary to take the whole plant, seeds of the plant are placed in the empty hole from which the plant was taken. Care is taken to remove only a few plants, flowers, or branches, so plenty remains to continue the supply.
The USDA defines "Organic" products that "are produced by farmers who emphasize the use of renewable resources and the conservation of soil and water to enhance environmental quality for future generations. Organic meat, poultry, eggs, and dairy products come from animals that are given no antibiotics or growth hormones. Organic food is produced without using most conventional pesticides; fertilizers made with synthetic ingredients or sewage sludge; bioengineering; or ionizing radiation."
"Responsibly Sourced" is a term used freely to say that your products come from sustainable and/or fair trade practices. It is used from diamonds that come from non-conflict areas to sea food and basically means that a product is not damaging the planet and the people on it any further.
In the oil industry it became popular after the deforestation the palm oil farms are causing came to light, most products that use it now say theirs is "Responsibly Sourced Palm Oil".
"Fair Trade" in Brazil refers to products that were harvested, farmed and produced by people who are being offered good working conditions and being paid fairly and in currency not by bartering (bartering gives an advantage to the "big city" people - the buyers - who usually have the upper hand when dealing with harvesters and farmers.)
In the US Fair Trade Certified Products "were made with respect to people and planet. Our rigorous social, environmental and economic standards work to promote safe, healthy working conditions, protect the environment, enable transparency, and empower communities to build strong, thriving businesses. When you choose products with the Fair Trade label, your day-to-day purchases can improve an entire community’s day-to-day lives."
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