"Detergent Doesn't Go Bad, Right?" Why Your Laundry Suffers When You Keep Using Old Detergent

Liquid: 6-12 Months, Capsule: 15 Months, Powder: 18 Months Recommended Usage
Ingredient Separation, Clumping, and Odor... Risk of Mold and Pipe Blockages
Experts: "Record Opening Date and Replace on Time for Safety"

Contrary to the common belief that laundry detergent does not spoil even after a long period, warnings have been issued that its cleaning power diminishes over time and it can even damage washing machines. Even if the detergent appears fine on the surface, the chemical components inside can separate or deteriorate over time, causing it to lose its original function.

Recently, the American eco-friendly detergent brand Blueland stated, "The active ingredients in detergent naturally decompose or separate over time, which can lead to a rapid decline in cleaning effectiveness." In general, laundry detergent is recommended to be used within one to two years from the manufacturing date. Once opened, exposure to air and humidity accelerates the rate of deterioration.

The rate of deterioration and recommended usage period vary depending on the form of the detergent. In particular, liquid detergents have a high moisture content, making them more susceptible to ingredient separation and microbial growth; therefore, it is recommended to use them within 6 to 12 months after opening. Capsule detergents can be used for up to 15 months, but care must be taken as exposure to moisture or heat can alter the coating. Powder detergents can be stored for up to 18 months if they remain dry and do not harden. However, they have the drawback of easily clumping even with slight humidity.

When deteriorated detergent is used, the most immediate issue is reduced cleaning power, but the problems do not end there. Residue left in the washing drum can promote the growth of mold and bacteria, and it can also lead to damage to the internal pipes of the washing machine or to fabrics. Some experts have warned, "When using old detergent, little to no foam is generated, stains are not properly removed, and leftover residue can clog the washing machine, causing odors and malfunctions."

Key signs that detergent has deteriorated include: separation or clumping in liquid detergent; hardening or dampness in powder detergent; loss of original scent or development of an unpleasant odor; musty smell on clothes after washing; reduced cleaning performance; and increased stains inside the washing drum. Experts recommend immediately discarding the detergent and checking the condition of the washing machine if any of these changes are observed.

Proper storage is crucial to maintain detergent performance for a long time. Experts recommend: storing detergent at a cool room temperature (10-25°C) away from direct sunlight; keeping it on a dry shelf or in a storage area rather than in a humid bathroom; closing the lid tightly after opening to minimize air exposure; not using liquid detergent for more than one year; and avoiding diluting detergent directly in the cap with water.

While eco-friendly brands are increasingly indicating recommended usage periods, this is not yet mandatory in Korea, so consumers must manage it themselves. A representative from a consumer organization advised, "Many people are unaware of the risk of deterioration when using laundry detergent for a long time. It is important to record the purchase and opening dates and develop the habit of replacing detergent in a timely manner."

Experts have warned, "Detergent is a basic product responsible for household hygiene. Neglecting old detergent can lead to reduced washing performance, washing machine malfunctions, and even health problems."