The food industry loves salt, it is a magic ingredient with the ability to change an unpalatable food to one that is flavoursome and appealing. As Heston Blumenthal stated, it is the most important ingredient in the kitchen. Let’s take bread as a food that uses the multiple functions of salt. Bread produced without salt has a vastly different taste to bread produced with salt – not only taste, but the texture is different, and 99.99% of consumers prefer their bread produced with salt. It may seem hard to believe, but bread is the single largest source of salt in our diet; yet bread is not salty like potato chips are salty. That is because the majority of salt is bound within the matrix and unavailable to activate our taste receptors. It is within the bread matrix that salt has some functions, salt controls growth of yeast and promotes the development of gluten structure/texture in bread, as well as adding or enhancing flavour. As a cook, baker or food manufacturer you would be crazy not to use salt. The reason for salts continued (increased in the case of Australia, if you trust the recent data from Australian division World Action on Salt and Health (AWASH)) use in processed foods, given the multiple health reasons not too, is the multiple positive functions salt has in the food matrix.
Take meat and cheese products as examples, both are high in salt and if a manufacturer was making a reformulated meat product (chicken patties or similar), reducing the salt would adversely affect texture and require other additives to replace the water-holding, protein-binding, and fat-binding functions of the salt. In cheese, additional additives would be needed to help promote good bacteria and inhibit bad bacteria during fermentation and aging. But what compounds can replace the function of salt, and what's the cost; consumers may not be able to afford or willing to pay for a significant increase in the cost of salt reduced foods. In addition, we must not forget the role salt plays in preservation, as it reduces water activity in foods and acts to control growth of pathogens and spoilage organism. If salt levels are decreased, it will be necessary to use other preservatives to ensure safe foods with a reasonable shelf life.
From a food industry perspective, in addition to processing and safety challenges involved in producing low sodium foods, there is also an economic consideration. If it becomes apparent to a food manufacturer that consumers prefer a higher concentration of salt over the current concentration, salt may be added to that food at very little cost. For example, the approximate price of salt is 34 cents/ kg, if food manufacturers wish to increase the salt concentration of bread by 5% the approximate cost would only be 0.000756 cents/100 g. Salt is very cheap and any substitute used will increase the cost of the product. Production of foods with reduced salt will require reformulation and additional associated costs of consumer testing and pilot plant tests. Are we as consumers willing to pay the extra costs associated with reduced salt products, or are we willing to accept inferior products? Possibly not. Are we willing to accept myriad new additives that will be needed to replace the functions of salt? Again, possibly not. While the flavour aspects of salt are undoubtedly the main reason why salt is in foods at the level it is, there are also technical reasons to maintain salt levels in foods
It is widely accepted we have a food supply that delivers to much salt for population health. How to fix the problem is the issue. The most effective strategy is to reduce the level of salt in manufactured foods, as they deliver 75% of dietary salt. The food industry correctly states salt reduction is not easy to do, and there are costs involved. And we as consumers are likely unwilling to accept increased costs that will be involved with salt reduction.
One thing for certain, the last thing we need is food manufacturers increasing the current levels of salt in foods, as AWASH reported recently. There is no need for more salt in bread, or increased levels in cereals. If voluntary food industry targets cannot be determined or met for specific foods, the next step should be to legislate maximum levels of salt in foods. Perhaps this is needed, if so, start with bread at a maximum level of 800mg NaCl/100g bread – this is a good compromise value, the functionality the bread matrix is maintained, taste is fine and will be a significant step forward in reducing population salt intake.
As (hopefully) explained over the past 4 blogs, salt is a problem with no easy answer.