Does soap have a shelf life?

Soap is a common cleaning product in our lives. Many people still like to use soap very much. Especially now there are many essential oil soaps and floral soaps on the market, which are even more popular. But did you know that soap also has a shelf life? Maybe you haven’t noticed, but soap has a relatively long shelf life. So, can soap still be used after it expires?

If the appearance and smell of expired soap have not changed significantly, you can continue to use it, but the effect will be less effective. If it has spoiled, it is better not to use it.

The main raw materials of soap are: soap base (mainly composed of saponified beef, mutton and coconut oil), antioxidants, flavors, pigments, etc. Under normal storage conditions, the shelf life of soap is generally three years. If soap is stored for a long time, its weight will become lighter and its hardness will increase. Generally speaking, long storage time has no obvious effect on the washing effect and it can continue to be used.

However, soap that has exceeded its shelf life is at risk of becoming rancid (commonly known as "deterioration"). In mild cases, yellow and black spots will appear on the surface of the soap, while in severe cases, oily sweat will appear. The detergency of rancid soap will decrease with the degree of rancidity. The reason for rancidity is that, on the one hand, the mixed fatty acids in soap contain a certain amount of unsaturated fatty acids, which are oxidized after long-term contact with air; on the other hand, the unsaponifiable matter contained in soap will decompose into fatty acids and glycerin after long-term contact with air and sunlight, causing rancidity. The resulting substances have an unpleasant odor.

How long is the shelf life of soap

Soap does have a certain shelf life, but it is relatively long. In general, soap is safe to use. If the soap has been used and is in a humid environment, it may cause bacteria to grow, leading to skin infection during use. So once you start using it, you should use it up as soon as possible.

The shelf life of laundry soap is officially three years, but in actual use it is fine as long as it is unopened and has not expired. Shelf life and expiration are two different concepts. I have a box of laundry soap that I have had for 10 years. I'm still using it, and it works fine. The soap will be fine for five years, but it will change its smell after that.