Below the salt

02-Jan-2008 - Last updated on 15-Mar-2017 at 16:21 GMT

Although no one ingredient can replicate the many characteristics of salt, flavour experts are doing their damnedest. Sarah Britton investigates

Lowering salt consumption across the world by 15% could save 8.5M lives by 2015, according to a recent study based on 23 countries led by London-based health charity King's Fund.

But it seems that despite these shocking figures, people are unwilling to cut down their salt intake. "We are biologically programmed to love salt," says chief flavourist at Synergy Gail Underwood.

Nevertheless, under pressure from the Food Standards Agency, food manufacturers are determined to reduce salt levels in their products. Synergy commercial director Steve Morgan claims that the firm is getting a lot of enquiries on salt reduction, but that the process is far from straightforward. "There are two key challenges with salt flavour: the flavour of the mineral itself; and its enhancing qualities, which lift the other flavours in the product," he says. "For example, in bakery, salt affects the flavour of dough, so it's two-fold."

Synergy has looked at ways of enhancing other flavours in bread to compensate for salt reductions. "If you can put more of a bread character into products, this can distract consumers from the lack of salt," says Underwood. "The bread crust is the main flavour from bread, so we're developing a slightly toasted bread character."

Although the salt content of bread isn't particularly high, because people consume vast amounts of it, there is demand for salt reduction, adds Hanneke Veldhuis, business manager for flavour innovation at DSM in the Netherlands. "The move to reduce salt started in products that used a hell of a lot of salt, such as ready-to-eat foods and soups. Here, yeast extracts work well, as they have a meaty, brothy taste profile," she says.

"But recently there has been pressure on cereals, bread, cheese and crackers. We use yeast extracts to reduce salt in these, but with the original taste of yeast dumbed down using our knowledge of enzymes, fermentation and yeast technology."

However, using yeast extracts has a knock-on effect. "You may need to replace some stabilisers - it's not a standalone solution," says Morgan. But he isn't about to let this stand in Synergy's way. "We're talking to a stabiliser company about teaming up together, to offer a broader solution. I'd like to see some joint stabiliser/flavour ingredients in the future."

But even when ingredients firms do come up with the goods, there are other criteria that they must meet. "In terms of our lactic yeast extract, it's proven to do the job," says Morgan. "I should have people banging the door down, but the noise around store cupboard ingredients is blocking the solutions. It doesn't really make sense as Marmite, which is based on yeast extract, is in kitchen cupboards across the UK."

In order to feed the UK demand for clean-label ingredients, the firm is looking towards naturally sourced solutions. Underwood explains that mineral extracts from lakes are an option. "There are about 30 different minerals, which are low in sodium and potassium and would enable us to make a cleaner declaration," she says.

Nick Price, senior flavourist at Ungerer & Company agrees that the demand for natural could be a barrier to progress. "A lot of it's down to the retailers and whether they'll accept the term 'flavouring'," he says.

Ungerer's Unsal salt replacer is classed as a flavouring and is based on kokumi - a taste enhancement made up of the breakdown particles from nucleotides. These are chemical compounds that enhance glutamic acid perception and increase saltiness.

Cost conundrum

It's not just the clean-label issue that is putting manufacturers off using salt replacers though. "Unsal is costly compared to salt, so manufacturers tend to just remove salt," says Price. "But this results in bland-tasting products, and it's no good if consumers are just adding the salt back at the table."

The firm has developed a flavoured version of Unsal in order to provide processors with a multi-functional offering. "If you can afford to flavour your food, you can afford our ingredient," says Price. "We're looking to launch cheese, garlic, onion and mixed vegetable-style flavours in the new year."

Damian Bellusci, commercial director at Create Flavours also notes that manufacturers are unwilling to spend a great deal on salt replacers. "Price is our main focus," he says. "There's no question you'll have to increase the price for salt replacers compared to salt. There have been good replacers out there for a while now, but manufacturers don't want to accept the on-cost involved. You can pick up salt for 12p per kg, while with replacers you're looking at anything from £2-10 per kg."

In the past, Create has worked with yeast extracts, but because they are expensive the firm has spent the past six months looking at other areas such as plant extracts. "We're just putting the finishing touches to a range of salt reduction ingredients to be launched in March. We are currently comparing them in savoury and sweet applications to monitor their flavour release," says Bellusci.

David Kilcast, business head of the sensory and consumer science group at Leatherhead Food International (LFI) doesn't have much faith in salt replacers.

"The majority of replacers all have serious deficiencies in taste profiles," he says. "Potassium chloride is the most widely used, but this has a very bitter taste."

He believes that the solution may lie in looking at different salt structures. "I have worked on a collaborative project looking at amorphous salt - a non-crystalline form of salt. By using a freeze-drying procedure, we were able to give a more aerated release." LFI found that the replacement of table salt with amorphous salt as a surface coating to savoury snack foods delivered a higher perceived saltiness. Kilcast explains that the surface coating of salt gave tastebuds a rapid hit of saltiness.

"We've also looked at the use of double emulsions. This involves changing the structure of salt and its position on the product to give a heightened perception," he says. "I think a lot of industry will be looking at this."

Sweet inspiration

Nottingham University's professor Andy Taylor suggests that sweeteners research may give clues to salt reduction. There's a sweeteners experiment which shows that with a single sensory system, such as taste, stimuli at sub-threshold levels can be detected when several are combined, he claims. "We always say: 'If you can't taste it, it's no good.' But maybe we're wrong. There's a lot of work in this area - people believe there is potential there. I don't think anyone's done such an experiment with salt, but I'd love to see if the result was the same."

Mastertaste technical director John Margetts agrees that this may well be a winning strategy. "The biggest problem with enhancing salt is introducing flavours that aren't welcome. We're looking at ingredients that can enhance salt, but remain at levels below the taste threshold."

The many different applications for salt mean that there is no silver bullet, but it is clear that steady progress is being made in many different categories.

Kilcast claims that it is a very much a tortoise and the hare scenario in that only manufacturers that move steadily will win the race to lower their salt levels. "Reduction by stealth will probably work best, but if competitors don't follow, you may lose the market to others," he warns. FM

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