Tuesday, March 31, 2015

The Effect of Soluble Fibre Enrichment on Taste Perception - Preliminary Evidence

By Pridhuvi Thavaraj (PhD candidate) and Eugeni Roura PhD and Senior Researcher, University of Queensland

Researchers at the Queensland Alliance for Agriculture and Food Innovation at the University of Queensland (UQ) are investigating the fascinating area of the effect of fibre on the perception of taste. In this article, UQ scientists Pridhuvi Thavaraj (PhD candidate) and Eugeni Roura (Senior Researcher) explain the findings of their research on the effect of soluble fibre on our perception of taste.

Dietary fibres are believed to have a beneficial effect on human health related to weight management, diabetes, cardiovascular diseases and cancers among other conditions (Chawla & Patil, 2010). Due to this, they are in the forefront of many public health diet campaigns that urge a higher fibre intake. The current recommended adequate intake of dietary fibre is 25 - 30g/day (Department of Health and Ageing & Council, 2005). To meet this adequate intake, many everyday foods are being enriched with different types of dietary fibre (Al'absi, Nakajima, Hooker, Wittmers, & Cragin, 2012). However, how fibre enrichment in foods affects taste perception has not yet been systematically investigated.

Recent findings have provided further evidence that the sense of taste plays an important role in nutrient sensing and food intake (Chaudhari & Roper, 2010; Laffitte, Neiers, & Briand, 2014). Foods that have been enriched with fibres have been linked to decreased consumer preference (Laguna, Primo-Martin, Varela, Salvador, & Sanz, 2014; Yılmaz, 2005; Zahn, Forker, Krugel, & Rohm, 2013). The main changes observed in food after fibre enrichment are related to texture, appearance, and taste (Devereux, Jones, McCormack, & Hunter, 2003; Zahn et al., 2013). In addition, it is known that fibre enrichment decreases taste perception, however most of these conclusions have been drawn using liquid food models that are not representative of solid foods (Baines & Morris, 1987; Hollowood, Linforth, & Taylor, 2002).

In our current research we studied the interaction between dietary soluble fibres (Beta-Glucan and Pectin powders) and the sensitivity to sweet, bitter and umami tastes using a tasteless and non-nutritious solid food taste delivery model (chewing gum) using a procedure known as the forced-choice ascending concentration series method of limits for best estimation of thresholds or BET). BET refers to the amount of tastant (eg sugar) required for the detection of taste (Lawless, 2013). A lower threshold means that a lower amount of tastant is required for perception. Our study found that regardless of the treatment, both soluble fibres significantly (P<0 .001="">) decreased the BET for sweet, bitter and umami tastes while no impact on salty and sour tastes was observed.

These results suggest that soluble fibre enrichment of foods have the potential to enhance some of the tastes of solid foods when adequately manipulated. Consequently, our findings have the potential to design food formulations with less taste enhancers (eg sucrose) which may contribute to lower energy intake and a better control of weight gain.

References:

1. Al'absi, M., Nakajima, M., Hooker, S., Wittmers, L., & Cragin, T. (2012). Exposure to acute stress is associated with attenuated sweet taste. Psychophysiology, 49(1), 96-103. doi: 10.1111/j.1469-8986.2011.01289.

2. Baines, Z. V., &; Morris, E. R. (1987). Flavour/taste perception in thickened systems: the effect of guar gum above and below c*. Food Hydrocolloids, 1(3), 197-205. doi: http://dx.doi.org/10.1016/S0268-005X(87)80003-6

3.Chaudhari, N., & Roper, S. D. (2010). The cell biology of taste. The Journal of Cell Biology, 190(3), 285-296. doi: 10.1083/jcb.201003144

4.Chawla, R., & Patil, G. R. (2010). Soluble Dietary Fiber. Comprehensive Reviews in Food Science and Food Safety, 9(2), 178-196. doi: 10.1111/j.1541-4337.2009.00099.x

Department of Health and Ageing, & Council, N. H. a. M. R. (2005). Nutrient Reference Values for Australia and New Zealand, Including Recommended Dietary Intakes Retrieved 17/05/2014, from http://www.nrv.gov.au/sites/default/files/page_pdf/n35-dietaryfibre_0.pdf

5. Devereux, H. M., Jones, G. P., McCormack, L., & Hunter, W. C. (2003). Consumer acceptability of low fat foods containing inulin and oligofructose. Journal of Food Science, 68(5), 1850-1854. doi: 10.1111/j.1365-2621.2003.tb12341.x

6. Hollowood, T. A., Linforth, R. S. T., & Taylor, A. J. (2002). The Effect of Viscosity on the Perception of Flavour. Chemical Senses, 27(7), 583-591. doi: 10.1093/chemse/27.7.583

7. Laffitte, A., Neiers, F., & Briand, L. (2014). Functional roles of the sweet taste receptor in oral and extraoral tissues. Curr Opin Clin Nutr Metab Care, 17(4), 379-385. doi: 10.1097/mco.0000000000000058

8. Laguna, L., Primo-Martin, C., Varela, P., Salvador, A., & Sanz, T. (2014). HPMC and inulin as fat replacers in biscuits: Sensory and instrumental evaluation. Lwt-Food Science and Technology, 56(2), 494-501. doi: 10.1016/j.lwt.2013.12.025

9. Lawless, H. T. (2013). Psychophysics I Quantitative Sensory Analysis (pp. 1-23): John Wiley & Sons.

10. Yılmaz, I. (2005). Physicochemical and sensory characteristics of low fat meatballs with added wheat bran. Journal of Food Engineering, 69(3), 369-373. doi: http://dx.doi.org/10.1016/j.jfoodeng.2004.08.028

11. Zahn, S., Forker, A., Krugel, L., & Rohm, H. (2013). Combined use of rebaudioside A and fibres for partial sucrose replacement in muffins. Lwt-Food Science and Technology, 50(2), 695-701. doi: 10.1016/j.lwt.2012.07.026