Resistant starch balances texture in reduced-fat biscuits, study

Replacing some flour content with resistant starch (RS) in short-dough biscuits is a good way of balancing out the detrimental effects of fat replacement on texture, according to a study.

The research published in the Journal of Texture Studies studied ways in which to counterbalance any sensory changes produced by fat replacement in short-bread biscuits.

The researchers from the Institute of Agrochemistry and Food Technology (IATA) in Spain found that “texture was the main issue when a percentage of fat was removed- the biscuits got harder and crumblier,” whereas high-fat biscuits had a softer texture.

However, “the addition of resistant starch (RS) to replace part of the flour proved to be a good way of balancing out the detrimental effects of fat replacement on texture,” wrote the researchers.

Resistant starch

Resistant starch is a starch degradation that is white in colour and a natural source of dietary fibre with a bland flavour and better texture and mouthfeel than other fibres.

The ingredient has documented health benefits, including intestinal/colonic health and important benefits in glycemic management. It is commonly used to replace flour in foods due to its suitable functionalities.

Fat replacement

Researchers used National Starch’s ingredient N-Dulge as a shortening replacement at 10 % and 20%. The fat replacer, launched in 2009, is a mixture of tapioca dextrin and starch. Its intended application areas are sweet baked products such as cookies.

“Compared with the control sample, replacing 10 or 20% of the shortening with N-Dulge affected the textural attributed most. A significant increase in hardness and crunchiness scores and a significant decrease in crumbliness were found.”

Odour or flavour attributes were not impacted significantly, nor pastiness.

To counterbalance the textural abnormalities, researchers replaced part of the flour content with RS that previous work (Laguna et all. 2011) showed reduced biscuit hardness and increased crumbliness unlike fat replacement.

The researchers suggested that among the popular biscuit segment, short-dough products are “the most popular” and said that “nutritionally, it would be advantageous to decrease their fat content while keeping their sensory properties unchanged.”

The study

The findings comprised a sensory analysis conducted by a panel of eight assessors, aged between 25 and 36, skilled in quantitative descriptive analysis and a consumer test of 100 untrained regular short-dough biscuit consumers.

 

 

Source: Onlinelibrary.Wiley

June 2012, Volume 43, Issue 3, pages 235-245

“Balancing texture and other sensory features in reduced fat short-dough biscuits”

Authors: L. Laguna, P. Varela, A. Salvador, T. Sanz and S.M Fiszman