What it is
The register’s chemical name for it: “2,3-Dihydroxybutanedioic acid.”
- EU register name (INCI)
- TARTARIC ACID
- CAS number
- 133-37-9 / 147-71-7 / 87-69-4
- EC number
- 205-105-7 / 205-695-6 / 201-766-0
What the register lists it for
These are the uses the European Commission’s CosIng register lists for Tartaric Acid in any cosmetic, hair roles first. They say why a maker might add it, not what it does in one formula, and they aren’t a safety rating.
- Buffering
-
Keeps the product’s pH (how acidic it is) steady.
Register definition: “Stabilising the pH of an aqueous medium in a narrow range even if an acid or base is added. Altering and/or maintaining a cosmetic product's pH at the desired level.”
- Fragrance
-
Gives the product its smell or covers an unpleasant one. A label may name each scent ingredient or group them as Fragrance (Parfum).
Register definition: “Imparting an odour or taste. Creating a perceivable pleasant smell and/or masking a bad smell.”
Where it sits on each label
US labels list ingredients from most to least, except that those at 1% or less may follow in any order. A name near the top is a large part of the formula. A label doesn’t mark where the 1% point falls, so further down, the order says little about how much is in it.
- Clarifying shampoos 1 label First five names: 0 of 1 Clarifying shampoos without it
- Deep conditioners 1 label First five names: 0 of 1 Deep conditioners without it
Every label, product by product (2)
- Camille Rose Clean Rinse Clarifying Shampoo Clarifying shampoo 20th of 34 names
- Mielle Babassu & Mint Deep Conditioner Deep conditioner 35th of 38 names
Each line runs from the first name on a label to the last; a dot is where this ingredient sits. Makers change formulas now and then; if the list on your bottle differs, go by your bottle.
Your next step
Other buffering ingredients on these labels
- Citric Acid 93 labels
- Sodium Hydroxide 25 labels
- Aminomethyl Propanol 15 labels
- Lactic Acid 12 labels
- Acetic Acid 7 labels
- Sodium Acetate 7 labels
- Disodium Phosphate 6 labels
- Sodium Lactate 5 labels
Updated · The name, numbers and uses come from the European Commission’s CosIng entry (CC BY 4.0); we write the uses in US spelling and put the hair ones first. The labels are each maker’s own. The order rule is the FDA’s Cosmetics Labeling Guide. All our sources are on the Sources page.