Trisodium citrate is the tri-basic salt of citric acid, used in beverage applications as a buffer in combination with citric acid to obtain desired pH value. In dry formulations, effective buffer systems play a particularly important role because of differences in the pH of the added water. Additionally, trisodium citrate enhances the effect of antioxidants by chelating trace metals. The combination of trisodium citrate and citric acid is extensively used in soft drink formulations due to the broad buffering range, namely pH 2.5 - 6.5, and for the pleasant and refreshing taste profile.
Beyond the commonly known and most frequently used dihydrate form (TSC) of trisodium citrate, Jungbunzlauer also manufactures trisodium citrate anhydrous (TSA). To produce TSA, water molecules of the TSC crystals are removed through a process patented by Jungbunzlauer, without destroying the original crystal matrix. The resulting crystals have a porous matrix that can absorb water and can be used as a carrier for different kinds of liquids. The good flowability of the product is not impaired by the uptake of a certain amount of moisture. These properties enable optimised dry blend formulations, such as instant beverages, and enhanced processing and product features of tablets for various applications.
TSA shows several advantages over its dihydrate equivalent in beverage and food applications:
- Generally, products which are hygroscopic are also prone to caking. This is not the case for TSA. Due to its low water content, TSA is able to absorb water from the environment while maintaining its excellent flowability. This property also allows TSA to increase the stability of dry mixes by absorbing moisture from other ingredients and the environment. This prevents agglomeration of powder in the tablet production process or moulds in the pipes or in the press, which are typically caused by moisture.
- TSA has a water content of 1% compared to TSC with 11 to 13%. This means that TSA has a 11 to 14% higher product content and is thus more efficient in the formulation. The higher product content also leads to reduced cost for handling, transport and warehousing.
- TSA can be mixed with other liquids and still remains a free flowing powder. For example TSA can take up 6% of oils and up to 9% of specific organic liquids such as colorants. These liquid absorption properties can be used to improve and optimise the dry-mixing production process of powders and the pressing of tablets.
- Comparing the solubility between TSA and TSC shows that TSA has a higher dissolution rate than TSC under equal conditions.
TSC has excellent buffering, sequestering and emulsifying properties and is widely used in the food and beverage industries, while TSA offers several advantages that are particularly beneficial in dry blends. The main advantage is its ability to absorb moisture, preventing powder agglomeration, extending the shelf life of the product and allowing optimised processing and product features. In addition, TSA has a higher product content owing to the absence of water, it is able to bind liquids like flavours up to 6% while remaining a free-flowing powder, and it has a better dissolution rate.
More information about Jungbunzlauer TSA can be found under the following link: https://www.jungbunzlauer.com/en/products/citrics/trisodium-citrate-anhydrous.html