Effect of sugar reduction and addition of corn fibre and polydextrose on pore size and syneresis of yoghurt

Abstract:

This study investigated the effect of sugar reduction and replacement by corn fibre and polydextrose on yoghurt gel pore size and syneresis. Five yoghurt formulations were produced with 9, 4.5 and 0% sucrose, and also 4.5% with added 2% corn fibre or polydextrose. The increasing demand for sugar reduction in dairy products justifies studies on new formulations such as fibre addition. Sucrose reduction from 9% to 0% led to a decrease in average matrix pore size and increased syneresis. Fibre or polydextrose addition effectively reduced syneresis, despite bigger matrix pore sizes. Fermentation profile, acidity and pH values were not significantly affected by compositional changes.

Conclusion:

The present study demonstrated that the presence and type of carbohydrates impacted the yoghurt microstructure in different forms (pore size) and syneresis. Reducing the yoghurt sucrose level from 9% to 0% led to a decrease in matrix pore size and increased syneresis. Moreover, the addition of corn fibre or polydextrose to a sucrose-reduced yoghurt increased the pore size of the matrix and decreased syneresis. The reduction or removal of sugar with or without the addition of fibre in a yoghurt formulation did not influence the fermentation time, neither acidity nor pH after 1d or 21d storage; however, sugar reduction and added fibres led to decreased syneresis at 1d, which significantly increase during shelf-life. In summary, sugar influences the physicalechemical properties of yoghurt and the addition of soluble fibres such as polydextrose can be a viable alternative for sugar replacement as fibres can modulate the characteristics of yoghurt reduced in sugar making it closest to traditional yoghurt.

There are some sensory studies in the literature concerning corn fibres and polydextrose (Allegeryer, Miller, & Lee, 2010a,b); however, future studies can be carried out focusing on sensory analysis using these fibres as a sugar substitute. In conclusion, the addition of soluble corn fibre and polydextrose in yoghurts as partial sucrose substitutes can be an alternative for the food industry, and thus meet a market demand from health-conscious consumers.

References:

Allgeyer, L. C., Miller, M. J., & Lee, S. Y. (2010a). Drivers of liking for yogurt drinks with prebiotics and probiotics. Journal of Food Science, 75, 212e219.

Allgeyer, L. C., Miller, M. J., & Lee, S. Y. (2010b). Sensory and microbiological quality of yogurt drinks with prebiotics and probiotics. Journal of Dairy Science, 93, 4471e4479.

[137] Gomes, E. G.; Carneiro, L. C. M.; Stephani, R.; De Carvalho, A. F.; Renhe, I. R. T.; Wolfschoon-Pombo, A; F.; Perrone, I. T. Effect of sugar reduction and addition of corn fibre and polydextrose on pore size and syneresis of yoghurt. International Dairy Journal, International Dairy Journal 129 (2022).