Glycaemic index, glycaemic load and dietary fibre characteristics of two commercially available fruit smoothies

Int J Food Sci Nutr. 2019 Feb;70(1):116-123. doi: 10.1080/09637486.2018.1481201. Epub 2018 Jun 11.


In light of the updated Eatwell Guide and the corresponding change in the consumption of fruit smoothies, the aim of this study was to measure the glycaemic index and load of two commercial fruit smoothies and to investigate the retention of dietary fibre following production. In vitro analysis was performed to identify fibre material (cellulose and pectins) using calcofluor staining and immunocytochemical labelling. A repeated measures cross-over study was conducted (n 10) to determine the glycaemic index (GI) and glycaemic load (GL) of the smoothies. Results showed that dietary fibre was still present in the smoothies after processing (16.9-17.5% cellular material by dry weight). The GI was low for both smoothies (39 and 36), whereas the GL was medium and borderline-low, respectively (11.4 and 9.7). The retention of fibre in these smoothies may have a potential positive effect on glycaemic response and may contribute to daily fibre requirements.

Keywords: Glycaemic index; cellulose; glycaemic load; mango and passion fruit smoothie; pectin; strawberry and banana smoothie.

MeSH terms

  • Adult
  • Beverages / analysis*
  • Blood Glucose / metabolism*
  • Commerce
  • Cross-Over Studies
  • Dietary Carbohydrates / metabolism*
  • Dietary Fiber / analysis*
  • Female
  • Food Handling
  • Fruit*
  • Glycemic Index*
  • Glycemic Load*
  • Humans
  • Male
  • Young Adult


  • Blood Glucose
  • Dietary Carbohydrates
  • Dietary Fiber