Use of the mineral salts was tested at both the lab and industrial scale, with the resulting breads found to be low in salt and acceptable to 122 consumers in terms of baking qualities, appearance, texture and taste, state the researcher in the International Journal of Food Sciences and Nutrition.
Salt is a difficult ingredient for bakers to eliminate given its importance in activating yeast, enhancing flavouring and extending the shelf-life of products however the additive has been hitting the headlines as excessive consumption can be linked to heart disease and strokes.
The pressure has been mounting on food manufacturers to reduce the salt content of their foods and the UK's food standards agency (FSA) recommendation of six grams of salt per day for the general population is understood to be more a realistic target for the next five years than the ideal healthy limit.
In the UK, Ireland and the USA, over 80 per cent of salt intake comes from processed food, with 20 per cent of salt intake coming from meat and meat products, and about 35 per cent from cereal and cereal products.
Responding to this pressure, formulators are investigating new ways of producing foods with lower salt intakes. Karen Charlton from South Africa's Medical Research Council, in collaboration with researchers from Sasko Milling and Baking (Division of Pioneer Foods) and the University of Cape Town, investigated the development of reduced-sodium bread where sodium chloride (NaCl) was partially replaced with potassium, magnesium and calcium salts.
Twenty-four different breads were baked and comparing the bread to the standard brown variety. The researchers report that the potassium, magnesium and calcium content could be increased by 55, 69 and 35 per cent, respectively, and still produce bread that is acceptable to consumers.
These increases in alternative salts translated intto a 32.3 per cent reduction in sodium content, they said.
When tested by a panel of 122 consumers, the bread with one-third the sodium content of standard brown bread was deemed acceptable in terms of appearance, texture and taste.
The UK has been leading the way with salt reduction. Earlier this year UK bakers were commended by Herefordshire Trading Standards for reducing the salt content from 2005 levels.
Indeed, a survey of 53 different bread samples showed that the average salt content was 1.2 per cent compared to an average of 1.34 per cent in November 2005.
The results of the Herefordshire study showed that the highest level of salt in bread today is 1.61 per cent while in 2005 the highest recorded salt content was 2.93 per cent - indicating that bakers are taking action.
Indeed Gordon Polson, director of the Federation of Bakers, commented earlier this year that the baking sector has made significant progress given the challenges that salt reduction presents.
"Since November 2005, when the baking industry announced its plans to reduce salt in bread, the industry has made significant strides in meeting the targets agreed with the FSA," he said.
"Although our members are happy to be working with the FSA on this issue, the reduction of salt in bread thus far has been immensely challenging for the entire industry as salt plays such a critical role in dough formation.
"It is widely recognised that any change that may diminish the flavour would be counterproductive to the objective of improving diets as it is acknowledged that bread plays an important role in a healthy, balanced diet."
Numerous scientists are convinced that high salt intake is responsible for increasing blood pressure (hypertension), a major risk factor for cardiovascular disease (CVD) - a disease that causes almost 50 per cent of deaths in Europe.
CVD is reported to cost the EU economy an estimated €169bn ($202bn) per year.
Source: International Journal of Food Sciences and Nutrition
November 2007, Volume 58, Issue 7, Pages 508 - 521
"Partial replacement of NaCl can be achieved with potassium, magnesium and calcium salts in brown bread"
Authors: K.E Charlton, E. MacGregor, N.H. Vorster, N.S. Levitt, K. Steyn