Yogurt Filtrate
INCI: Lactobacillus/Yogurt Ferment Filtrate
A filtered, microbe-free fermented extract from yogurt cultures. Contains amino acids, peptides, and probiotic by-products.
Overview
Yogurt filtrate is the cosmetic ingredient produced by fermenting milk (or a milk-protein-based medium) with Lactobacillus and Streptococcus cultures (the same cultures that make food yogurt), then filtering the result to remove the live bacteria. What remains is a sterile, microbe-free liquid containing:
- Lactic acid — small amounts, contributing mild AHA action
- Amino acids and small peptides — from milk protein hydrolysis during fermentation
- Postbiotic compounds — the metabolic by-products of the bacterial fermentation, including small lipids, vitamins (especially B-complex), and unique fermentation-derived molecules
- Calcium and milk minerals — in small amounts
The “postbiotic” angle is the modern marketing positioning. Where probiotics are live bacteria and prebiotics are fibres that feed them, postbiotics are the by-products of bacterial metabolism. There is real research support for postbiotic skin care — particularly for skin microbiome support, anti-inflammatory action, and barrier repair.
It is animal-derived (made from cow’s milk) so it is not vegan. Lactose-intolerant customers can safely use topical yogurt filtrate; the lactose is metabolised during fermentation.
Shelf life is 12-18 months for liquid form.
What it does in a formula
- Postbiotic skin microbiome support — modulates the balance of skin bacteria
- Mild AHA exfoliation from natural lactic acid content
- Skin barrier support through amino acids and peptides
- Anti-inflammatory action from fermentation by-products
- Skin conditioning — gentle softening effect
It is one of the more interesting “fermented skincare” actives. The Asian skincare market has been ahead of the European/American market on fermented ingredients for over a decade, and yogurt filtrate is one of the simpler examples.
How to use
Add to the cool-down phase, below 40 C. Heat-sensitive (peptides and amino acids).
Usage rates by product type:
- Postbiotic-positioned face creams: 2-5%
- Hydrating toners: 2-4%
- Sensitive-skin face creams: 1-3%
- Sheet mask essences: 2-5%
- Eye creams: 1-3%
- Body lotions (gentle): 1-3%
- Hair conditioners (rinse-off): 1-3%
It pairs naturally with prebiotic ingredients (inulin, agave extract), with other fermented actives (rice ferment, sake ferment), and with niacinamide.
Best for / Worst for
Best for: postbiotic and microbiome-positioned skincare, sensitive-skin formulations, K-beauty inspired product lines, eczema-supportive lotions, gentle exfoliating face creams.
Worst for: vegan formulations (animal-derived from cow’s milk), strict casein- or milk-protein-free formulations (a small number of customers with severe milk-protein allergy may react), strong-acid-positioned products (the lactic acid content is too low for headline AHA claims).
Common pitfalls
Vegan positioning. Yogurt filtrate is made from milk and is not vegan. Plant-based alternatives (rice ferment, soy ferment) exist.
Lactose intolerance. This is not a concern — fermentation metabolises the lactose. Communicate this if customers ask.
Confusing filtrate with live yogurt. The cosmetic ingredient is bacteria-free. Adding raw yogurt to a cosmetic is not the same and will introduce microbial contamination.
Heat sensitivity. Add to cool-down phase.
Substitutes
- Lactobacillus ferment lysate — purer postbiotic without dairy.
- Rice ferment (sake ferment / Saccharomyces ferment) — plant-based fermented alternative.
- Soy ferment — plant-based fermented alternative.
- Bifida ferment lysate — different bacterial postbiotic.
- Mild lactic acid + amino acid blend + niacinamide — for measurable postbiotic-style effects from individual ingredients.