Acid-sensitive gum may fill you up for longer, cut snacking
Researchers from School of Chemical Engineering at the University of Birmingham, UK report the development of an aqueous solution based on gellan gum that forms a solid gel in the stomach, curbing appetite.
“The solution we designed takes advantage of the body’s natural process of digestion to structure itself into a gel,” explained Fotis Spyropoulos, who is working on the project. “We are now working on a key element of the formulation – how to get it to release energy slowly. This is a crucial part of our work since people would feel unhappy by having a full stomach but no reward from it in terms of energy.”
The researchers are looking to use the new solution in a breakfast drink or a type of porridge.
According to the researchers, once the low acyl gellan solution has been consumed, it forms a gel in the stomach’s acidic environment. The strength of this gel is said to be carefully controlled so it is firm enough to provide a prolonged sense of fullness, thereby reducing the likelihood of snacking and eating unhealthy foods.
The Birmingham scientists have also reportedly designed the gel structure to progressively weaken, and eventually break down and pass through the digestive tract. This is important as it will allow for the desire to eat to return in time for the normal consumption of lunch or dinner.
The novelty factor
A similar concept was reported by researchers from the University of Buffalo in collaboration with McNeil Nutritionals in 2007. In that instance, a beverage containing alginate-pectin and calcium was found to form a stable gel in the stomach and boost the feeling of fullness.
A subsequent study with 29 overweight and obese women found a 10 per cent reduction in energy intake between lunch and dinner as a result of consuming the beverage (American Journal of Clinical Nutrition, December 2007, Vol. 86, pp. 1595-1602).
In an email communication with NutraIngredients, Dr Spyropoulos said that the approach of the Birmingham researchers is to achieve the formation of the gel “in a controlled way, inside the stomach and by taking advantage of its acid environment is a novel one”.
The McNeil study looked at creation of an ionic gel, whereas the Birmingham approach is an acid gel. “This is precisely the reason why the subjects in [the McNeil] study were given two different solutions to consume one after the other; the first one containing the hydrocolloid (or mixture of hydrocolloids) that eventually forms the gel and the other the calcium solution that induces the gelation,” explained Dr Spyropoulos.
“We believe that it is easier to gain consumer acceptance by having only one product and not a combination,” he added.
“It is impossible to have a single solution when mixing a hydrocolloid like alginate and calcium, as gelation is more or less instantaneous, and therefore you will be consuming a gel rather than a ‘beverage,’” he said.
By focussing on the acidic environment of the stomach, the new approach does not need to deliver both the hydrocolloid and the ions to the stomach but only the former, said the researcher.
ChemEng approach
“Our project is, to our knowledge, the only study that actually approaches this idea from a chemical engineering prospective,” said Dr Spyropoulos. “By this I mean that we are actually looking at the stomach as an additional ‘process’ that the food is subjected to. So we are looking at how to ‘use’ this process to provide the desired benefit; satiety in this case.
“What differs in our approach, from those taken by others, is that we, besides understanding structuring (i.e. gel formation) in the stomach, are also looking into how de-structuring (weakening/collapsing) can be induced so that the gel can eventually break down and pass through the digestive tract.
“Equally important is to design the structure to slowly and controllably release energy while it occupies the stomach, which is another aspect of this work that we’re currently putting a lot of effort towards,” he said.
Dr Spyropoulos confirmed that discussions with a few industrial people have taken place regarding the project’s progress and whether it can eventually be commercialised, “but nothing ‘concrete’ in terms of partnership”, he said.
“We are optimistic that the outcomes from this work will appeal to industry as our funding comes from the Diet and Health Research Industrial Club (DRINC), on the panel of which there are a number of major food retailers and manufacturers that were heavily involved in deciding which proposals should be funded,” he added.
With the project in its early stages, Dr Spyropoulos added that the nothing has been published in scientific journals yet, although a paper is in preparation for publication in a peer-review journal.
Market growth
The research taps into the burgeoning weight loss and management market, estimated to already be worth $7bn (€5.2bn) globally. It also has implications for diabetes.
With 50 per cent of Europeans and 62 per cent of Americans classed as overweight, the food industry is waking up to the potential of products for weight loss and management.
