Abstract

Background: The energy value of a substance is essential in nutritional labeling. However, the available energy of newly developed highly cross-linked phosphate starch (HCPS-N) and modified cellulose (MC) are unknown.

Objective: To evaluate the available energy of HCPS-N and MC, an indirect and simple method which was applied as an indicator of the fermentability based on the breath hydrogen excretion, was used.

Methods: HCPS-N was made from tapioca starch by polymerization in the presence of 0.5% phosphoric acid. MC was made from microcrystalline cellulose, maltodextrin, and karaya gum to attain a highly stable suspension. The present study was carried out using a within-subject, repeatedmeasures design. Blood was collected at 30 min intervals for 3 h after the ingestion of 30 g of a test substance. The end-respiratory gas was collected for 14 h after ingestion of 5 g of a test substance to evaluate the available energy.

Results and Discussion: Plasma glucose and insulin levels did not elevate after the ingestion of HCPS-N, although they increased significantly after glucose ingestion. In the experiments to evaluate the available energy, breath hydrogen excretion after ingesting HCPS-N did not increase distinctly during the experiment. Breath hydrogen excretion after preceding HCPS-P (0 kcal) ingestion was also markedly smaller compared with the peak value at 4 h after FOS ingestion. For the ingestion of MC, breath hydrogen excretion increased scarcely, and the basal level remained until the end of the experiment.

Conclusion: The available energies were evaluated to be 0 kcal/g for HCPS-N and 1 kcal/g for MC in healthy humans.

Keywords: Available energy, breath hydrogen, dietary fibers, fermentability, highly cross-linked starch, modified cellulose.