What Is Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate?
Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate is an active liquid that comes from fermenting silkworm cocoon extract with the friendly bacteria Lactobacillus. Silkworm cocoons are rich in proteins such as sericin and fibroin, plus amino acids that hold water well. When these proteins meet Lactobacillus in a controlled tank, the bacteria break down large protein chains into smaller, skin-loving fragments and add extra skin-conditioning compounds produced during fermentation. After the brew is complete it is carefully filtered to remove solids, leaving a clear ferment filtrate that is easy to work into creams and serums.
The move to use fermented silk in beauty care started in South Korean skin care labs in the early 2000s, inspired by traditional silk bathing practices said to soften skin. Fermentation was added to take the natural silk proteins and make them more bioavailable while boosting the hydrating effect. Today formulators value this ingredient for its light feel and ability to draw moisture, which fits well with modern “skin-microbiome-friendly” trends.
You will most often spot Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate in moisturizing lotions, lightweight serums, sheet masks, hydrating toners, anti-aging creams and soothing after-sun gels. Because it is water soluble it blends smoothly into both simple water creams and richer emulsions.
Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate’s Cosmetic Benefits/Uses
In skin care formulas this ingredient is prized for one main role.
Humectant: It attracts water from both the product and the surrounding air, then binds that water to the skin’s outer layers. This helps keep skin plump, smooth and comfortable while giving formulas a fresh, non-greasy finish.
Who Can Use Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate
This ferment filtrate suits most skin types including dry, normal, combination and oily because its main job is to pull water into the skin without leaving a heavy film. Sensitive skin generally tolerates it as well since the fermentation step breaks the silk proteins into gentler fragments, although those with a known silk allergy should avoid it.
Because the base material comes from silkworm cocoons, the ingredient is not considered vegan and may be unsuitable for strict vegetarians who avoid insect derived substances. Anyone following a plant only lifestyle will likely prefer an alternative humectant sourced from plants or synthetic fermentation.
Current safety data show no specific risks for pregnant or breastfeeding women when the ingredient is applied topically in cosmetic amounts. That said this is not medical advice and anyone expecting or nursing should run any skincare product past a qualified doctor to be on the safe side.
The filtrate does not make skin more sensitive to sunlight so it is not classed as photosensitising. It also plays well with most other common skincare ingredients and does not interfere with sunscreens or makeup.
Potential Side Effects/Adverse Reactions
Side effects and reactions to the topical application of Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate can vary from person to person. The points below list potential issues even though they are unlikely for most users when the ingredient is formulated properly.
- Mild redness or stinging on very sensitive or compromised skin
- Allergic contact dermatitis in individuals allergic to silk or other insect proteins
- Transient tingling if layered with strong exfoliating acids or retinoids
- Rare breakouts in acne prone skin if the overall formula contains comedogenic oils
If any negative reaction occurs stop using the product and seek advice from a healthcare professional
Comedogenic Rating
Rating: 0 (non-comedogenic)
Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate is a lightweight water based humectant with no oil or fatty acids that could clog pores. It sits on the skin surface only long enough to draw in moisture then evaporates or rinses away easily. Because it does not leave an occlusive film and has a very low molecular weight after fermentation, it offers little opportunity to block hair follicles.
Suitable for acne-prone or breakout-prone skin since it will not add to pore congestion, provided the rest of the formula is equally low in comedogenic ingredients.
As with any hydrating agent, pairing it with heavy butters or waxes could raise a product’s overall pore-clogging potential even if this ferment itself remains innocuous.
Summary
Lactobacillus/Silkworm Cocoon Extract Ferment Filtrate is primarily a humectant that attracts water and binds it to the outer skin layers, helping skin look plump smooth and comfortable. The fermentation process breaks silk proteins into smaller peptides that absorb quickly and boosts the filtrate with additional conditioning metabolites created by Lactobacillus.
While not as famous as hyaluronic acid or glycerin, this silk ferment enjoys moderate popularity in K-beauty hydrating toners serums and masks thanks to its light feel and “microbiome friendly” story. Western brands are starting to adopt it in niche moisturizers and after-sun gels.
Current research and industry usage show the ingredient to be low risk for irritation or sensitization when used in typical cosmetic levels. Still, everyone’s skin is unique so it is wise to patch test any new product containing this ferment before regular use.