Ammonium ferric citrate added to salt

Ammonium ferric citrate is an additive that is usually green or brownish red and odorless. When we hear the word additives, we associate it with words like "toxic" and "unhealthy". However, ammonium ferric citrate is a benign additive. Adding ammonium ferric citrate to table salt will have unusual effects. It exists as a nutritional growth agent and has a hygroscopic effect, which keeps the salt dry. Below we will introduce in detail the role of adding ammonium ferric citrate to table salt.

1. Edible salt produced in Dingyuan Salt Mine, Chuzhou, Anhui Province was used as a carrier, and ammonium ferric citrate was added as an anti-caking agent. The salt was stored for several months to simulate the actual situation. Samples were taken at 0, 30, 180, and 210 days to determine the whiteness, water-insoluble matter, and ammonium ferric citrate content of the salt. The agglomeration of the salt was observed, and the surface state of the crystals after agglomeration was observed using a microscopic scanning electron microscope. The results showed that the content of ammonium ferric citrate remained almost unchanged within 210 days, and had no effect on the water-insoluble content of salt, but had a greater effect on whiteness. Combined with the anti-caking effect, the dosage of ammonium ferric citrate can be controlled within 40 mg/kg. Through microscopic scanning electron microscopy observation, it was determined that the anti-caking mechanism of ammonium ferric citrate is to change the crystal lattice.

2. A method for indirectly determining the content of ammonium ferric citrate in table salt by spectrophotometric determination of iron content using o-phenanthroline as a colorimetric agent. This method improves the color development conditions, making the test results accurate and reliable, and the operation process is fast and simple. The appropriate amount of reagent addition was determined through conditional experiments. Interference tests verified that this method can eliminate the interference of calcium, magnesium, potassium, iodine, and sulfate ions commonly found in table salt. This method has a detection limit of 0.1 μg/mL for ammonium ferric citrate, and has good linearity between 0.1 mg and 0.5 mg in the determination system, with a linear correlation coefficient of 0.999 9. The standard deviation of samples with an ammonium ferric citrate content of 23 mg/kg determined 20 times using this method is 0.35 mg/kg.

3. Using salt produced in Zigong, Sichuan as a carrier, ammonium ferric citrate was added as an anti-caking agent. After tracking the physical and chemical indicators and anti-caking effects of salt, it was found that ammonium ferric citrate added to edible salt in an appropriate proportion has the effect of delaying the agglomeration of salt. The physical and chemical indicators of the product are stable and meet the standard requirements, providing a new choice for my country's well salt companies to solve the problems of salt agglomeration and anti-caking agent replacement. This paper mainly explores the application and stability of ammonium ferric citrate in table salt.