Will round salt revolutionise food development?

Parthasarathi Dastidar and Pushpito K. Ghosh, part of a research group from the Central Salt & Marine Chemicals Research Institute in Bhavnagar, India, developed the new free-flowing table salt in collaboration with a major food company in India.

The breakthrough could impact numerous food makers.

"Standard common salt tends to cake easily, especially under humid summer conditions, "​Dr Pushpito Ghosh told FoodNavigator.

" Moreover, even if there is no caking, the flow of granular substances can be retarded by high contact area between the granules. A sphere is the best geometry to reduce the latter."​

Ghosh pointed out that any crystalline material such as salt has well defined faces. For example, a standard salt crystal is cubic in morphology and has six square faces.

"Any deviation from this morphology would be thermodynamically less favourable and therefore would not form without some kind of intervention,"​ he said.

The focus of others has been on mechanical intervention during crystallization. But Dastidar and Ghosh used a chemical intervention instead.

"The basic observation that cubes can be transformed into dodecahedron is not new but no one had thought perhaps from the angle that we did,"​ said Ghosh.

The challenge for the team was to carry out such modification under ambient conditions so that crystallization in solar pans was viable. They found that glycine was successful for this purpose.

"Thereafter, the main challenge was to find a way out of the problem of high requirement of glycine for the desired habit modification,"​ said Ghosh.

"This was solved by introducing the concept of recycling excess glycine in a fresh lot of saturated brine. However, this would not have worked but for the fact that the recycling led to dissolution of coprecipitated glycine leaving the condition of the salt intact."​

The end result, says Ghosh, is that the food industry has a potentially more convenient and aesthetically appealing product to offer. The fact that the modified salt contains a trace amount of glycine (0.5-1.0 per cent w/w) may also be a boon to the food industry since glycine, although non-essential amino acid, is known to impart a certain amount of refreshing and sweetish flavour.

"The salt tastes fine, but we have so far not carried out any studies on differentiated taste. Another advantage is that a solution of the salt would be completely clear unlike salts, which contain insoluble inorganic anti-caking agents.​

"We also expect that FDA clearance would be simple since glycine should be a perfectly acceptable additive in salt."​

Ghosh also said that the team was looking for enquiries from interested industries. "We may need to work in partnership with them to make the invention truly commercially viable,"​ he said.

"We will also have to work with them to catalogue the advantages and drawbacks, if any, of the product."​

The team has already filed patent applications and the PCT application has now entered the National phase of filings. Ghosh, Dastidar and colleagues plan to publish their findings in the 5 July issue of Crystal Growth & Design.