The effect of natural alternative sweeteners lucuma, yacon, and monk fruit on the growth of probiotic lactic acid bacteria

  • Elizabeth Kahler

Student thesis: Masters ThesisMasters by Research


Research continues to emerge indicating the potential destructive effects of non-nutritive sweeteners on the viability of gut microbe populations. Recent trends demonstrate an increase in demand for natural and plant-based replacements for artificial sweeteners. Yacon, lucuma, and monk fruit are novel ingredients that exhibit low calorie sweetening power in addition to multifunctional attributes that make them useful as alternatives to artificial sweetening substances. Fermentable sugars contained within these sweeteners have the potential to display prebiotic impact for active growth of beneficial probiotic bacteria. Lactic acid bacteria are a populous group of probiotic organisms with a long established history of consumption in fermented foods and an association with functional impacts on the structure of the gut microbiome. There is little research pertaining to the influence of sucrose substitutes on the viability of probiotic bacteria, variable specificity of the different strains, and how compatibility with different sweeteners plays a major role in their survival. In this study, we investigated the effect of novel sweeteners on the acidification of skimmed milk during fermentation with probiotic bacteria. In culture medium, acidification kinetics were inhibited in the presence of the sweeteners, suggesting that the sugars and/or other compounds contained in the sweeteners displayed mechanisms of inhibition which possibly suppressed growth of the lactic acid bacteria. However, there was no significant difference in viability (p > 0.05) between in treatments and control. This study was limited and experiments were cut short by the sudden lockdown due to the Covid-19 pandemic. It is suggested that future research employ chromatographic techniques to analyse the sugar composition of the sweeteners. Viability analysis experiments which yielded inconclusive data should be repeated. Additionally, variations in starter cultures may be explored for their specific enrichment of gut probiotic populations at the strain level. A sensory component will help inform new product development.
Date of Award23 Mar 2021
Original languageEnglish
Awarding Institution
  • Abertay University
SupervisorBoon Chu (Supervisor) & Sarah Cottin (Supervisor)

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