Absolutes, Hydrosols and Infused Oils: How They Differ From Essential Oils

Safety first. A different name does not make a product gentler than an essential oil. We did not find a source that says so. Do not swallow any of these products, and read Essential oil safety before putting a scented product on skin.

Absolutes and concretes

One research paper on a tobacco-family plant describes how these are made. The plant is extracted with n-hexane to give a concrete. The same paper says a concrete is the first step toward a plant absolute, and that the second stage extracts the concrete cold with ethanol. [2] Researchers group absolutes, concretes, resinoids and oleoresins as "aromatic extracts" used as food flavorings and in fragrance. [3]

That description comes from one study of one plant. We did not find a source describing the methods used for flower absolutes such as jasmine or rose, which are covered on Jasmine and Rose Oils.

Proper evidence not found: we searched PubMed and Europe PMC for solvent extraction of jasmine and rose absolutes and for solvent left in finished absolutes. We found no source that reports leftover solvent levels, and none that compares absolutes with distilled oils for skin reactions.

Hydrosols (floral waters)

A 2024 review explains that when plants are distilled, two layers form as the vapor condenses, and the hydrosol is the water layer. [4] It holds traces of essential oil, usually under 1 gram per liter, plus other water-soluble plant substances. [4] Sources use many names for it, including hydrolate, aromatic water and floral water. [4]

A hydrosol is not a weak copy of the oil. The review says hydrosol and oil compositions "typically differ quantitatively and often qualitatively." [4]

Traditional use (not evidence of safety). The same review notes that in Iranian culture hydrosols are used with sweeteners to make drinks. [4] We do not advise swallowing hydrosols. The reviewers themselves say a recommended, non-toxic daily intake still needs to be established. [4] If someone swallows one and feels unwell, call Poison Help at 1-800-222-1222 in the US.

Germs can grow in them. A French study analyzed 22 orange blossom and rose hydrosol samples. Microbes grew in all of the hydrosols studied when stored in non-sterile containers, even at 5 °C. [5] In contaminated samples counts reached about 7 log10 CFU/mL (roughly 10 million per milliliter), against a French pharmacopeia limit of 2 log10 (about 100). [5] The authors concluded that the oil in a hydrosol is not enough to keep it stable, and that preservatives or aseptic packaging would be needed. [5] This was a laboratory analysis of samples, not a study of illness in people.

Labels are loose. The review points out that there are no legal definitions or standards for hydrosols, and that wastewater or decoction residues must not be mislabeled as hydrosols. [4] A product called "rose water" or "floral water" therefore does not tell you how it was made. See Who Regulates Essential Oils?.

Infused (macerated) oils

An infused oil is plant material steeped in a fatty carrier oil. One 2025 laboratory study added basil or sage to cold-pressed oils and measured fatty acids and antioxidant activity, not health effects. [6] Under the NIEHS definition of pressing or distillation, a steeped oil is not an essential oil. [1]

Proper evidence not found: we searched PubMed and Europe PMC for microbial safety and botulism risk in herb-infused oils and found no usable source. We do not give preparation instructions here. A pharmacist can advise on any infused oil you already own.

The FDA says a massage oil meant only to lubricate skin is a cosmetic, but one marketed to relieve aches or relax muscles is a drug or possibly both. [7] Carrier oils are explained on Carrier Oils Explained.

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