Effect of Hydrothermal Treatment of Depigmented Turmeric ( Curcuma longa L.) on Cecal Fermentation in Rats

Raw depigmented turmeric powder (TP) and hydrothermally treated TP (HT‐TP) contain non‐digestible saccharides with fiber and RS contents of 53.3% and 39.9%, respectively. Starch granules in TP and HT‐TP are observed under a petrographic microscope. The native and partly digested starch granules hydrolyzed by digestive enzymes, are also observed under SEM. In an animal study, cecal total SCFA concentration in rats fed 10% TP diet followed by 10% HT‐TP diet is ( p < 0.05) higher than the control diet, while acetate and n ‐butyrate concentrations in 10% HT‐TP diet are ( p < 0.05) lower than in the 10% TP diet, which is still higher than the control diet. These data indicate that starch in HT‐TP is resistant to gelatinization and/or enzymatic digestion; thus, HT‐TP may be a useful food material conducive for increasing intestinal fermentation.