Actually, there is no definitive answer to this question because both hot-process soap and cold-process soap belong to the category of soaps, both obtained from the saponification reaction between fats and alkali. The most obvious difference lies in the fact that hot-process/cleansing bases save the step of preparing the soap base from scratch. Instead, they directly take the soap base, heat it to melt, and then add some beneficial ingredients. Some claim that cleansing bases are industrial soaps, but this is a statement born out of misunderstanding. Both soap bases and cold-process soaps require the reaction of fats with alkali. When producing both in large quantities, auxiliary equipment is necessary. Some persist in claiming that cold-process soap is made by hand, mixing fats and alkali manually. While this is not entirely incorrect, consider how much volume one can handle by hand. For instance, making a 2-kilogram batch might exhaust your hands, not to mention aiming for hundreds of kilograms of cold-process soap in a day. At this scale, you undoubtedly rely on equipment like electric heating tanks and stirrers. At this point, these devices are no different from soap bases. While you could manually mix a small quantity of soap base, are you going to limit yourself to producing only 1-2 kilograms per day? Home production is feasible, but once you enter the realm of industrial production, would you employ a hundred people to stir soap in basins every day? Proper stirring demands time and speed, not everyone can achieve the same quality. With the same recipe and tools, different individuals might produce entirely different soaps at the same time due to the limited heat generation time of the alkali. Imagine continuously stirring a pot with a stick, wouldn't that exhaust you? When a product enters mass production, it must rely on machinery to save time and reduce the chances of errors. To achieve mass production, both soap bases and cold-process soaps require the assistance of equipment.
What are the differences in composition between soap bases and cold-process soaps? There are differences. Let's start with cold-process soap. Cold-process soap has the simplest and relatively complex methods. The simple method involves combining a type of fat with alkali to create soap. For example, using olive oil with alkali, coconut oil with alkali, peanut oil with alkali, pig fat with alkali, or reclaimed oil with alkali can produce soap. Let's not discuss their foaming properties or washing sensations at this point; instead, let's focus on this as the simplest soap-making method. Of course, the more complex method requires understanding the characteristics of each oil and its benefits for the skin. For example, a cold-process soap might contain palm oil, coconut oil, olive oil, jojoba oil, honey, vitamin E, glycerin, and other components in specific proportions, followed by alkali according to their saponification values. Mixing these ingredients results in a very high-quality soap.
Now, what about hot-process soap/cleansing bases? Compared to cold-process soap, hot-process soap has a much more extensive list of ingredients, and these ingredients are essential and cannot be randomly added or removed. The proportions in every aspect are precise; a slight increase or decrease in any element can significantly impact the final product, unlike cold-process soap. Additionally, the materials for hot-process soap aren't raw materials or first-pressed oils; they must be refined into fatty acids. The cost of this refinement is high since it involves refining products from crude oil, leading to a price that's 40% higher or more than the crude oil itself. These refined fatty acids, along with glycerin, sugar, sorbitol, vitamin E or C, citric acid, propylene glycol, sodium laureth sulfate, sodium cocoyl isethionate, sodium lauryl sulfate, disodium EDTA, etc., undergo saponification with alkali. The engineering and technical content required for this process far surpasses cold-process soap. Therefore, dismissing hot-process soap as inferior is incorrect. In fact, its technological complexity is considerably high. Even compared to shower gels, shampoos, and facial cleansers, if the proportion or operation of the saponification reaction is incorrect, the entire batch might end up as waste. Many assume that hot-process soap is chemical soap, but in reality, each ingredient is extracted from palm oil, coconut oil, fruits, or sugarcane, which are mild components. The naming has just evolved to sound more chemical and less straightforward.
So, what's the difference in washing sensation between hot-process soap and cold-process soap? Every proportion in hot-process soap is precise to the last percentage, ensuring there are no residual fats left unreacted. On the other hand, cold-process soap allows for personal preferences to add a bit more or less fat. Its saponification reaction depends on the heat generated by alkali. With time, as the soap matures, there might be residual fats unreacted due to the saponification reaction. Consequently, the pH of cold-process soap gradually decreases from initially being over 13 to around 9. However, some fats might remain unreacted. It's advisable to use this soap sooner; otherwise, it might turn rancid. The only downside is an unpleasant odor, but it's still usable for bathing. Since cold-process soap mostly completes saponification with fats, it feels slightly smoother than hot-process soap. Hot-process soap has fat proportions of around 40% to 50%, falling short of the over 80% fat content in cold-process soap. However, in the field of cosmetic cleansing soap, hot-process soap is primarily used. There's no instance of a cosmetics company using cold-process soap for facial cleansing soap. Popular products like DHC Olive Soap, The Body Shop's facial cleansers, and Shiseido's facial soaps are all made with hot-process soap. Why? Possibly due to the relatively lower pH of hot-process soap, its transparency, and the ease with which it can be reprocessed by melting and adding additional ingredients to achieve desired effects.
These points illustrate the fundamental differences between hot-process soap and cold-process soap. Many versions on the internet merely echo popular opinions, with people commenting without having been in hot-process or cold-process soap workshops. Some claim that even ordinary soaps like Safeguard are chemical soaps without understanding their production processes. This is misleading for readers and consumers. Let's clarify regarding Safeguard being a chemical soap. Safeguard's primary raw material is soap granules, obtained from saponification and salting out of palm oil, yielding soap granules and glycerin. Therefore, glycerin is an inherent component. However, the content of glycerin in soap granules is low because most of it is extracted.
Some might ask why Safeguard turns dark when burned. Consider an item with a fat content of around 80%-what do you think happens when it's burnt? The answer is evident.
To explain Safeguard's production process briefly, it involves using a soap production line comprising mixers, grinders, extruders, and printers. Soap granules, typically 25 kilograms per pack, are poured into the mixer for thorough mixing, where colorants and other materials can be added. If multiple mixers are available, additives can be incorporated into any mixer. After mixing, the mixture is automatically conveyed to the grinder, where it's ground into soap sheets to ensure a better fusion of ingredients
. Subsequently, the soap sheets pass through the extruder, the primary machine for soap production. After extrusion, soap bars of desired sizes are obtained, passing through a printer equipped with molds to shape the soap bars. As the soap passes through the printer, it's stamped (or embossed). The result is finished soap bars that need final trimming before packaging. The entire process is incredibly fast, and producing hundreds of thousands of soap bars per day on one production line is effortless.
WhatsApp: 8618948240310
Email: Minajiang@boymay.net
001 Xinmin Second Road, Xinle Industrial Park, Maan Town, Huicheng Area, Huizhou Guangdong 516057 China
