Fermentation technologies to obtain bread with increased fibre content and reduced starch digestibility and calorie density

Project Details

Status: Active
Investment: $194,580
Commodity: Wheat
Organization: University of Alberta
Investigator: Michael Gaenzle

White wheat bread is a staple in the North American diet, but is also considered a calorie dense and high glycemic food.

Why is this research important for Alberta ag?

White wheat bread is a staple in the North American diet, but is also considered a calorie dense and high glycemic food. However, depending on the recipe, the fermentation processes used in bread production, and the baking process, the glycemic index of bread can range from 50 to 100 (with white wheat, straight dough bread at one end of the scale and whole grain/whole flour sourdough bread at the other end).

Sourdough fermentation does not consistently reduce the glycemic index of bread, but multiple studies document that the use of sourdough fermentation in combination with high fibre baking reduces the glycemic index of bread. This effect has been attributed to the impact of lactic acid on starch-protein interactions; in addition, sourdough fermentation reduces the detrimental effect of bran on the texture and volume of bread and hence improved shelf life and sensory quality.

Current information on the metabolic potential of sourdough lactobacilli suggest that additional avenues to achieve a reduced starch digestibility through enzymatic starch modifications at the dough stage are possible, however, these options remain to be explored for use towards improved quality and nutritional properties of bread.

This project aims to build on past studies and to additionally make use of metabolic properties of sourdough lactobacilli that were discovered only recently to increase the fibre content of bread and to reduce the starch digestibility.

What benefits can producers expect from this research?

Wheat is a major crop in western Canada, but Canadian consumers are increasingly avoiding wheat because of either real or perceived gluten intolerance. This work aims to benefit crop producers by restoring consumers' confidence in products from wheat and improve consumer perception of wheat and its role in the Canadian diet.

How will these research findings reach producers on-farm?

Results will be presented at industry-specific conferences and at international symposia focusing on cereal chemistry, sourdough baking, or the use of lactic acid bacteria in food fermentations.