Campden BRI: Alginate gel-in-oil emulsions can slash fat in bakery by 50%

11-Mar-2014 - Last updated on 11-Mar-2014 at 14:08 GMT

Campden BRI has reduced fat content in sponge cakes by 50% and saturated fat by 30% using an alginate gel-in-oil emulsion to substitute hard fat

Alginate gel-in-oil emulsions can be used to half the fat content of cakes and biscuits, according to research from Campden BRI.

The research firm has found that the seaweed material can be used to form thermal stable gels that can replace hard fat or oils in bakery. The alginate is incorporated into a water-in-oil emulsion where it forms solid droplets upon contact with the calcium irons present, creating a gel-in-oil emulsion.

Campden BRI’s bakery science manager Dr Charles Speirs said that the alginate could be introduced into the water-phase of oils or incorporated into a hard bakery fat at the liquid form stage.

“It’s something we’ve done in the lab and we’re keen to scale this up,” Speirs told attendees at last month’s Bakery Innovation Europe conference in Munich, organized by Fi.

“We think this has legs. You’ve got a good fat replacement option here,” he said.

The work Speirs and his team have done was based on a 1992 patent granted to Mars Incorporated. Speirs was one of the inventors on Mars’ patented solution.

Little impact on volume, texture or shelf life

Campden BRI has done testing on sponge cakes and short-dough biscuits but Speirs recommended that the fat replacer be used in a blend of regular fats, rather than as a complete fat substitute. He advised using it at a level of up to 25% of total fat.

Speirs noted that while overall fat reduction was important, the saturated fat reduction was also of interest, particularly in cakes. Testing in cakes was done using a 50:50 gel-oil emulsion replacing hard fat at levels of 25% and 50%. At 50% replacement, findings showed that saturated fat was reduced by more than 30%.

The testing in cakes showed that there was little impact to the volume, appearance, texture or shelf life. “Hard fat in cake is there to help stabilize bubbles. We need to maintain bubble strength as the baking powder does its work - we don’t want them to rupture. This is to ensure a nice, high volume cake. We can replace significant levels of the hard fat with this material and still get the same, fine bubble structure, similar volume, and similar appearance but with reduced fat content,” he said.

He added that gels have very similar water activity to the hard fats it is replacing. “The take-home message there is that you can reduce the total fat content with an aqueous system and have a similar water activity, which means shelf life is not compromised.”

In biscuits, the stack height, width and length was not impacted when the gel-in-oil emulsion replaced 50% of the hard fat in the product. Campden did test replacement at 75%, but found that gluten started to develop and biscuit height and texture started to change at this level.

Bonus: Cost savings and nutrition

Speirs said there would also be “significant cost-saving potential” because manufacturers would essentially be replacing one gram of fat with one gram of water (the alginate emulsion). “You’re basically swapping fat for vegetable oil, so in terms of cost structures, I think it stacks up.”

Asked if the alginate material had any nutritional benefits when incorporated into cakes or biscuits, he told BakeryandSnacks.com: “Oh yes. Independent research found that it slows down the rate of absorption in the gut – it makes you feel fuller for longer. This sounds incredible, because we can do a reduced-fat product that makes you feel fuller for longer.”