Since starch is the major component of the rice kernel, the change
of its physicochemical properties during pasta-making processes will
dominate the properties of rice pasta. Despite the dramatic changes
induced by the parboiling process, new and different (according to
the extrusion conditions) starch molecule rearrangements were
observed in the dried pasta. Pasting and thermal properties, and
crystalline order suggest a different organization of starch granules in
milled rice pasta, accounting for the different cooking quality. In
particular, conventional extrusion seems to induce the perfection of
the small crystalline regions resulting in a low water absorption. On
the contrary, the extrusion-cooking process caused strong interactions
of amylopectin and/or amylose. Consequently, the product had
a low cooking loss but a high firmness.
Further studies are underway to optimize both the pastamaking
process and formulation in order to reduce the hardness of
the cooked product, while keeping as low as possible the cooking
loss. Also, regarding brown rice pasta, the role of fibre and of its
interactions with starch seems to warrant investigation, also in
view of the ever increasing popularity of high-fibre pasta and of the
associated technological problems.