Fibre may replace trans-fats for snack formulations

Inulin is already extensively used as a fat and sugar replacer, but the new studies report that the prebiotic fibres can be used as a non-fat-flavouring solution in snack bars, according to results published in the International Journal of Food Science & Technology​.

Researchers led by Vanessa Capriles from Sao Paolo University report that substitution of partially hydrogenated vegetable fat, used as the flavour fixative agent, with inulin-oligofructose increases the dietary fibre content of the finished product sevenfold, with similar overall acceptability.

Furthermore, the glycaemic index was reduced by 25 per cent.

“This study showed that it is feasible to replace the fat fixative agent with a non-fat-flavouring solution enriched with inulin and oligofructose in snack production,”​ wrote the authors.

“The results from this study also indicate that bioactive ingredients were successfully incorporated into a convenience food such as a snack, while maintaining the high sensory acceptability typical of this food product,”​ they added.

The study taps into the two sides of healthy food - adding in health promoting ingredients, and removing unhealthy ingredients, in this case trans fats.

Trans fats and heart health​

Though trace amounts of trans fats are found naturally, in dairy and meats, the vast majority are formed during the partial hydrogenation of vegetable oil (PHVO) that converts the oil into semi-solids for a variety of food applications.

Trans fats are attractive for the food industry due to their extended shelf life and flavour stability, and have displaced natural solid fats and liquid oils in many areas of food processing.

But scientific reports that trans fatty acids raise serum levels of LDL-cholesterol, reduce levels of HDL-cholesterol, can promote inflammation can cause endothelial dysfunction, and influence other risk factors for cardiovascular diseases (CVD), has led to a well-publicized bans in New York City restaurants, and other cities, like Chicago.

In the food industry this has been mirrored by an increase the in pressure on food manufacturers to reduce or remove trans fatty acids from their products and reformulate.

The food industry as a whole has expressed its commitment to removing trans fatty acids from its products, but such reformulation is not straightforward and presents challenges.

Commercial baked goods such as crackers, cookies and cakes, along with many fried foods, like french fries and doughnuts contain trans fats.

The new study looked at inulin and oligofructose (Beneo Synergy1, Orafti) to replace trans-fats in snack bars. The new snack had low fat levels of around 0.1 per cent, and a fibre content of 15.3 per cent.

When tested by 42 consumers, the inulin-oligofructose-containing bar had an acceptability score of 6.6 compared to 7.4 for the traditional bar, flavoured with the fatty fixative agent.

“The healthy low-fat fibre-enriched snack produced presented the high sensory acceptability typical for this food product type,”​ they concluded.

Source: International Journal of Food Science & Technology​
​October 2009, Volume 44, Issue 10, Pages 1895-1901
“Effect of fructans-based fat replacer on chemical composition, starch digestibility and sensory acceptability of corn snacks”​
Authors: V.D. Capriles, R.A.M. Soares, M.E.M. Pinto e Silva, J.A.G. Areas