How to judge whether soap saponification is good or bad?

A good soap saponification reaction means that the grease and lye react fully and completely to produce a gentle, stable and safe soap.

You can evaluate soap saponification comprehensively from the following dimensions, through a combination of sensory judgment and scientific testing:

1. Core judgment criteria: whether saponification is complete (the most important safety indicator)

Incomplete Soap saponification means that there may be unreacted strong bases (sodium hydroxide) left in the soap, and the use of such soap can irritate or even burn the skin.

1). pH testing (the most objective and reliable method)
This is the preferred scientific method to determine whether saponification is complete.
Methods: After the soap body matures (usually 4-6 weeks after the soap is removed and cut), the soap surface is wetted with distilled water and then measured with a precision pH test strip or pH meter.
Standard:
Good (safe) :p H value is usually between 7-10. The ideal handmade soap has a pH between 8-9.5, which is slightly alkaline and mild and non-irritating.
Poor effect (dangerous) :p H value higher than 10 indicates that there is too much lye residue and incomplete saponification. Absolutely not for use on the skin.
2. Tongue test (traditional but extremely discreet method)
This is a very ancient method that uses the "prickly" sensation of the tongue to the base. Please note: This method is risky and not recommended for novices. If you must try, be extremely careful.
Method: Quickly tap the dry soap noodles with the tip of your tongue and leave instantly.

Standard:
Good effect: only a faint, "electric shock"-like slight numbness, no continuous burning sensation. It means that the alkali has basically reacted completely.
Poor effect: Feeling a strong, persistent burning or tingling sensation, like a bite. This indicates that the alkali content is too high and the saponification is incomplete.

2. Judgment of the appearance and touch of the finished product
1). Observe the structure of the saponic body
Good results:
The texture is uniform and delicate, the color is consistent, and there is no obvious water-oil separation, oil spots or white powder (soda ash, alkali precipitation, only affects the appearance, not the use).
The surface is smooth and flat, and the internal structure is tight, with no or very few bubbles.
Poor effect:

Visible oil spots: dark oil droplet-like spots on the surface, which is a sign that the oil is not fully reacting.

Soda Ash is too bad: While white powder is harmless on its own, it can sometimes mean that the soap is too low or the saponification is not ideal when entering the mold.

Weeping: Liquid seeping out from the surface, which may be water, glycerin, or unreacted lye, is a clear problem soap.

Separation: The soap body is clearly divided into two or more layers with different textures.

2).Touch test

Good results:
The soap body is hard and solid, and it has hardness when pinched but will not be bothered.
The surface is delicate and smooth to the touch.
Poor effect:
It feels soft and sticky, and is easy to deform when pinched, like plasticine. This could mean incomplete saponification or excess moisture. There is a mucus or oiliness on the surface.

3. Judgment of user experience

In the end, a good bar of soap still has to be tested by use.
1). Cleansing power and skin feel
Good results:
It can produce a rich, fine and stable foam.
The washing feeling is refreshing and the cleaning power is sufficient, but the skin is not tight, dry, or itchy after use.
Even without extra fat, it feels gentle.
Poor effect:
The foam is sparse and disappears quickly.
The skin is noticeably dry, tight, and even itchy and tingling when used. This is a typical manifestation of excessive alkalinity.
2). Durability
Good effect: the soap body is hard, not easy to absorb water and soften, slow loss during use, and relatively durable.
Poor effect: the soap body is soft and rotten, and quickly turns into a paste when exposed to water, which is very undurable.

The soap saponification equipment made by has the ability to completely saponify, our engineers also have more than 30 years of saponification technology, we provide saponification system, saponification drying system, soap production equipment, printer, packaging machine and other complete production equipment. If you like our equipment, please contact us.