Production process of triply citric acid (potassium)

The poster is referring to sorbic acid, right? There are three types of sorbic acids: sorbic acid, potassium sorbate, and calcium sorbate. Sorbic acid is insoluble in water; it must first be dissolved in ethanol or potassium bisulfate before use. Its use is inconvenient and it is irritating, which is why it is not commonly used ； Calcium sorbate has a limited scope of use as specified by FAO/WHO, so it is not commonly used either ； Potassium sorbate, on the other hand, does not have these drawbacks; it is soluble in water and has a wide range of applications. It can often be found in various foods such as beverages, dried fruits, and canned goods ； Here I would like to focus on potassium sorbate: it is an unsaturated hexacarboxylic acid ； Potassium sorbate available on the market is typically in the form of white or light yellow particles, with a purity level of 98%–102% ； It has no odor or only a slight odor; it absorbs moisture easily and oxidizes to turn brown. It is stable to light and heat, with a relative density of 1.363. It decomposes at 270°C, and the pH of its 1% solution is 7–8. Potassium sorbate is an acidic preservative with strong antibacterial properties, capable of inhibiting the growth and reproduction of molds ； It primarily works by inhibiting the dehydrogenase system in microorganisms, thereby suppressing their growth and exerting an antiseptic effect; it is effective against bacteria, molds, and yeasts ； Its effectiveness decreases as pH increases; antibacterial activity reaches its peak at pH 3, and it still retains antibacterial properties at pH 6, although the minimum inhibitory concentration (MIC) cannot be lower than 0.2%. Experiments have shown that food items that have not been sterilized, when soaked in potassium sorbate solutions at pH 3.2, have a shelf life 2–4 times shorter compared to those soaked in solutions at pH 2.4. Sorbic acid, potassium sorbate, and calcium sorbate all have the same mechanism of action; their toxicity is lower than that of benzoates and parabens. The allowable daily intake for these substances is 25 mg/Kg, which is 5 times higher than that for benzoates and 2.5 times higher than that for parabens, making them relatively safe food preservatives ； In our country, it can be used in foods such as soy sauce, vinegar, pasta sauces, jams, pickles, canned goods, and some types of alcohol.

Thank you! It is indeed sorbic acid (potassium); I was careless when writing that day. However, I would like to know about its production process; it seems hard to find information on the internet.

The production process for sorbic acid is as follows: Acetaldehyde is used to synthesize crotonaldehyde in the presence of a catalyst; then crotonaldehyde reacts with ethylene to produce a polyester. This polyester is subjected to hydrolysis to yield sorbic acid, which is subsequently refined to obtain the final product, sorbic acid. The production process for potassium sorbate is as follows: sorbic acid is reacted with potassium hydroxide (potassium carbonate), followed by decolorization and drying to yield the final product, potassium sorbate