The present invention aims to provide a manufacturing method of instant rice which may be restored to edible rice simply by adding hot water. The method includes a first pressurized-steaming step for steaming raw material rice under pressure while the raw material rice is being agitated, and forming a gelatinized layer on a surface of the raw material rice, a hydration step for hydrating the raw material rice having the gelatinized layer formed on the surface, a tempering step for making moisture content of the hydrated raw material rice uniform, a second pressurized-steaming step for steaming the hydrated raw material rice under pressure while the raw material rice is being agitated, and gelatinizing the raw material rice to a center, a dehydration step for dehydrating the raw material rice that is gelatinized to the center, and an expansion step for expanding the dehydrated raw material rice.

The present invention aims to provide a manufacturing method of instant rice which may be restored to edible rice simply by adding hot water. The method includes a first pressurized-steaming step for steaming raw material rice under pressure while the raw material rice is being agitated, and forming a gelatinized layer on a surface of the raw material rice, a hydration step for hydrating the raw material rice having the gelatinized layer formed on the surface, a tempering step for making moisture content of the hydrated raw material rice uniform, a second pressurized-steaming step for steaming the hydrated raw material rice under pressure while the raw material rice is being agitated, and gelatinizing the raw material rice to a center, a dehydration step for dehydrating the raw material rice that is gelatinized to the center, and an expansion step for expanding the dehydrated raw material rice.

Systems and methods are disclosed that include providing a cooking system that comprises a burner assembly and a heat exchanger submerged in a vessel. The burner assembly includes a high velocity burner and a low velocity burner, the high velocity burner configured to provide the necessary high velocity, volumetric flowrate through a fluid duct of the heat exchanger that includes a plurality of compactly-arranged, alternatingly-disposed vertical and horizontal tubes passing through the fluid duct, and the low velocity burner configured to significantly reduce and/or substantially eliminate lift off that could result from operation of only the high velocity burner. The heat exchanger is submerged in the vessel with the tubes of the heat exchanger open to the vessel to allow ingress and egress of a fluid contained within the vessel.