What Is Aspergillus/Rice Ferment Lees Extract Filtrate?
Aspergillus/Rice Ferment Lees Extract Filtrate comes from sake making, where rice is fermented by the mold Aspergillus oryzae. During this process, a by-product called rice lees forms, rich in amino acids, peptides, sugars, vitamins and minerals released from the rice as it breaks down. Cosmetic chemists filter an extract of these lees to create a clear liquid that is easy to blend into skin care formulas.
Traditional Japanese brewers noticed that their hands stayed soft and youthful after years of handling fermented rice. This observation led beauty brands to study the ingredient and adapt it for creams, serums and masks. Today manufacturers steep rice lees in water or a mild solvent, let the beneficial compounds dissolve, then filter out solids and sterilize the liquid. The result is a lightweight ingredient that delivers nutrients without the heavy feel of oils.
You will most often see Aspergillus/Rice Ferment Lees Extract Filtrate in hydrating toners, brightening essences, anti-aging serums, sheet masks, soothing lotions and hair conditioners. Because it is water based, it slots easily into both simple moisturizers and more advanced treatments aimed at glow, firmness and overall skin comfort.
Aspergillus/Rice Ferment Lees Extract Filtrate’s Cosmetic Benefits/Uses
This ferment brings two main actions to personal care products.
- Skin conditioning: The mix of amino acids, sugars and vitamins helps skin hold moisture, boosts softness and supports a smoother texture. Over time it can make the complexion look brighter and more even.
- Emollient: While light in feel, the filtrate forms a thin comforting layer that reduces roughness and gives formulas a silky slip, making application pleasant and leaving skin supple instead of greasy.
Who Can Use Aspergillus/Rice Ferment Lees Extract Filtrate
This ferment filtrate is generally well tolerated by all skin types. Dry or mature skin benefits from the added moisture while oily or combination skin appreciates the lightweight, non greasy feel. Sensitive skin usually handles it without issues because it contains no known harsh acids or fragrances, though anyone with a history of mold or ferment allergies should proceed carefully.
The ingredient is plant based and derived from rice, so it is suitable for vegans and vegetarians as long as the finished product has not been tested on animals.
No research suggests that Aspergillus/Rice Ferment Lees Extract Filtrate poses risks to women who are pregnant or breastfeeding. That said this is not medical advice and anyone expecting or nursing should run all skincare products past a qualified healthcare professional to be safe.
The filtrate does not make skin more sensitive to the sun and can be used day or night without extra precautions beyond daily sunscreen.
Potential Side Effects/Adverse Reactions
Side effects from topical use vary from person to person. The points below outline potential reactions only. When the ingredient is properly formulated most users will experience none of these issues.
- Allergic contact dermatitis resulting in redness or rash
- Mild stinging or burning on application, especially on compromised skin
- Itching caused by sensitivity to rice proteins or the Aspergillus ferment
- Rare acne flare ups in individuals prone to fungal acne
If any of these reactions occur discontinue use and consult a healthcare professional.
Comedogenic Rating
Rating: 0 / 5 This filtrate is water based, contains virtually no oils or heavy waxes and absorbs quickly without leaving residue that could clog pores. Fermented rice compounds are lightweight and sit on the skin surface instead of blocking follicles. As a result it is considered non comedogenic.
Suitable for acne-prone or breakout-prone skin.
No special interactions with acne medications or other actives have been reported, so it layers easily within most routines.
Summary
Aspergillus/Rice Ferment Lees Extract Filtrate mainly conditions skin and works as a soft emollient. Its blend of natural amino acids, peptides and sugars pulls in water, improves smoothness and leaves a silky afterfeel without heaviness. The ingredient has gained steady popularity in K-beauty and J-beauty lines, though it is still less common in Western brands.
Current data shows it is safe for all skin types with a very low chance of irritation or pore clogging. Still, skin care is personal so perform a quick patch test when trying any new product that features this ferment to make sure it agrees with you.