Two fruits currently being mined for this potential have been long-recognised for their nutritional properties. However, it is only recently that research has been conducted into their use as processing aids as both become available on an industrial scale in Europe.
The reputation of baobab fruit is still growing since it secured EU novel food approval three years ago, despite having been used for generations in Africa as a cure-all remedy.
By contrast, the dried d'Argen plum, or prune, has been in Europe for significantly more than three years. But it was not used as an aid to reformulation and processing until recently due to supply problems.
However both are now widely available and, while research into them continues, both have already proved useful as processing tools in areas such as flavour enhancement and healthy reformulation.
Availability
Because baobab is still new to the EU, manufacturers have been slow to pick up on it, says Lucy Welford, marketing manager at baobab product supplier PhytoTrade Africa. The unfortunate timing of the global downturn did not help, she adds. However, as interest in the fruit grows, research into its benefits increase, she says.
Activity around prunes has been held up for other reasons. Previously prunes and other stone fruits had to be pitted through the Ashlock Method, where a machine hit their 'sweet-spot', driving stones out the other side, says Kevin Matchett, commercial director at fruit and fruit ingredient supplier, JO Sims.
The method caused problems for further processing. If the strike was off centre, it could shatter the stone, sending fragments into the fruit.
Earlier this year, JO Sims became the first UK distributor for prunes pitted using California prune producer Sunsweet's method, thanks to a partnership it forged with the company. Here, instead of being struck, the stone is squeezed through the fruit's skin. The procedure is 20 times more effective than the Ashlock method. Instead of fragments being left in the fruit, if the pit is not removed, it can be easily sorted through various optical methods, allowing prunes to be more easily processed for ingredients purposes.
healthy Reformulation
There's increasing interest in the sugar alcohol sorbitol and malic acid found in prunes as flavour enhancers to replace fat, sugar and seasonings such as salt, says Matchett. "What we are seeing with prunes is that they are conferring an element of functionality to products, while obviously being 100% fruit."
JO Sims recently tested the flavour enhancing properties of prunes on an industrial chocolate-chip muffin recipe with the help of an independent bakery consultant.
The addition of prune fibre powder allowed them to reduce sugar, salt and vegetable oil content – most impressive being salt with 70% removed and maintain the same taste profile, says Matchett.
The amount of cocoa powder, an expensive commodity, also had to be cut to deliver a flavour profile close to the original, he adds, delivering an additional economic advantage.
Baobab fruit has shown similar properties. Welford says its addition to canned fruits at the South African branch of one the largest canned fruit companies enhanced their flavour. Its addition to cereal bars containing fruit also added to the fruit's flavour. Previous baobab testing for its health benefits also revealed its ability to cut down on bitter tastes.
chicken marinades
Aside from more obvious bakery applications, both fruits can aid reformulation in other sectors. University of Arkansas research found prunes could augment taste and reduce or eliminate the use of phosphates in chicken marinades. This also led to consumers saying the marinated chicken breast fillet was more tender and just as juicy with prunes, the university reported.
The study followed previous investigations of the ability of prunes to bind moisture into animal protein. Athough meat protein lost slightly more moisture when cooked, prunes performed better than phosphates when frozen and thawed. This was due to the sorbitol in prunes acting as a humectant or water-binding molecule, aided by their high fibre content.
Water binding capabilities are also vital in baking. Prunes can improve crumb texture when added to moist bakery products such as muffins and cakes, says Matchett. This can also extend shelf-life by as much as one or two days, he adds.
The high antioxidant content of baobab may also enhance shelf-life, although its recent introduction to Europe means this has not yet been examined in great detail, says Welford. Their high levels of fibre, magnesium and calcium also show further promise for processing applications, she says, although more work remains to be done here.
One area that has already been examined is baobab's ability to help jams and jelly manufacturers. It enhances the flavour of other fruits and adds its own tanginess, but it's also a natural source of pectin, enabling baobab powder to make better gelatines, Welford explains.
scratching the surface
Despite all this potential, since 2010 only five new products containing baobab and 96 containing prunes have been launched, market analyst Mintel says.
Most of the prune launches concerned prunes as a "wrinkled dried fruit" instead of an industrial ingredient, says Matchett. 95% of EU prune sales are in this form, he adds. "We are scratching the surface in terms of the benefits and the opportunities."
Unfortunately, this could remain the case in the short term. Processors may not want to boast that they have enhanced functionality or lost unhealthy components by adding fruit, says Douglas Mackay, general manager for ingredients at JO Sims.
For example, for meat products it would probably not be advisable to mention fruit additives, despite their all-natural credentials, he says.
The prune also generally suffers from a negative image. "It did give off a bit of a stigma and my generation did view prunes as old fashioned and remembers being force-fed prunes at school dinners many years ago," says Matchett. "They were known as a food to keep [bowel movements] 'regular'."
However, he says consumer perceptions are changing. Younger generations make more positive associations with them. "You'd talk about prunes giving gut health benefits and it's almost cool and fashionable." He adds that this has been brought about by their inclusion in products such as yogurts.
Exactly how ingredients derived from baobab and plum and used as processing aids will be labelled remains unclear. In some contexts manufacturers are avoiding the connotations associated with prunes by calling them dried plums, Mackay adds.
But whether the fruits appear on labels or not, no doubt the European food industry will welcome, and benefit from, continuing research into their strengths as processing aids.