Microwave vacuum-dried durian flour and its application in biscuits

Durian is one of most popular fruits due to its nutritional values and unique flavor. Durian products have been continuously developed to meet market needs. In this study, durian (Durio zibethinus Murr.) cv. 'Monthong' was subjected to microwave vacuum-drying at 1,200 W to produce durian flour for use in biscuits that are normally made from wheat flour. The microwave treatment induced starch gelatinization to a significant extent. As a result, compared to the wheat flour, the durian flour had lower viscosity, pasting temperature, gelatinization temperatures, and enthalpy of gelatinization but higher water absorption capacity. Dough properties including development time, dough stability, time to breakdown and the phase angle tangent of the durian dough were less than those of the wheat dough. The elastic modulus (G') and viscous modulus (G″) of the durian dough were higher than for the wheat dough. All the tested durian doughs had higher G' values than G″, indicating a viscoelastic structure. Substitution of wheat flour with durian flour should not exceed 50% to obtain reasonable dough properties and baking quality of durian biscuits.

Sulphur-containing compounds of durian activate the thermogenesis-inducing receptors TRPA1 and TRPV1

Durian (Durio zibethinus Murr.) is classified as a body-warming food in Indian herbalism, and its hyperthermic effect is empirically known in Southeast Asia. To investigate the mechanism underlying this effect, we focused on the thermogenesis-inducing receptors, TRPA1 and TRPV1. Durian contains sulphides similar to the TRPA1 and TRPV1 agonists of garlic. Accordingly, we hypothesized that the thermogenic effect of durian is driven by sulphide-induced TRP channel activation. To investigate our hypothesis, we measured the TRPA1 and TRPV1 activity of the sulphur-containing components of durian and quantified their content in durian pulp. These sulphur-containing components had a stronger effect on TRPA1 than TRPV1. Furthermore, sulphide content in the durian pulp was sufficient to evoke TRP channel activation and the main agonist was diethyl disulphide. From these results, we consider that the body-warming effect of durian is elicited by TRPA1 activation with its sulphides, as can be seen in spices.