Process and apparatus for the production of short cooking time rice

Abstract

A process for the production of short cooking time rice is characterized by that hulled rice of at least 10% moisture content, if required in packaging suitable for ready cooking, is heat treated for 1 to 30 minutes continuously or interrupted by equal or alternating capacity microwave radiation, to reach maximum 130° C. An apparatus for the production of short cooking time rice comprises a microwave furnace with a tunnel made from a suitable material, wherein the rice packed into packages is movable within the tunnel by a conveyor. Regarding the easy and short process, a remarkable energy safing is possible.

1 - 30 . (canceled)  
   
   
       31 . Process for the production of short cooking time rice comprising the steps of arranging hulled rice of at least 10% moisture content in bags, microwave heat treating said hulled rice in an apparatus comprising a microwave furnace having a tunnel, for 1 to 30 minutes, continuously by equal or interrupted by alternating microwave treatment, to reach a maximum temperature of 130° C., and said microwave heat treating step comprising treating said hulled rice with 0.05 to 4 W microwave power per gram hulled rice, and using microwaves of a frequency between 300 MHz and 10 GHz.  
   
   
       32 . Process according to  claim 31 , wherein said arranging step comprising arranging hulled rice of from 11 to 13% moisture content in said bags.  
   
   
       33 . Process according to  claim 31 , wherein said microwave heat treating step is carried out for 1 to 12 minutes.  
   
   
       34 . Process according to  claim 31 , wherein said microwave heat treating step is carried out for 3 to 5 minutes.  
   
   
       35 . Process according to  claim 31 , wherein said microwave heat treating step comprises treating said rice with 0.3 to 2.0 W microwave power per gram hulled rice.  
   
   
       36 . Process according to  claim 31 , wherein said microwave heat treating step comprises treating said rice with 0.25 W microwave power per gram hulled rice.  
   
   
       37 . Process according to  claim 31 , wherein said microwave heat treating step is performed with microwaves of a frequency of 2450 MHz.  
   
   
       38 . Process according to  claim 31 , wherein the microwave exposure is related to the mass unit of rice on steady or alternating capacity value (W/g).  
   
   
       39 . Process according to  claim 31 , wherein said arranging step comprises packing said hulled rice in polyethylene air-proof bags before the microwave treatment.  
   
   
       40 . Process according to  claim 31 , wherein said arranging step comprises packing said hulled rice in coated paper bags before the microwave treatment.  
   
   
       41 . Process according to  claim 31 , wherein said arranging step comprises packing in perforated bags used for ready cooking before microwave treatment.  
   
   
       42 . Process according to  claim 41 , wherein said packing step comprises packing said hulled rice in perforated polyethylene bags.  
   
   
       43 . Process according to  claim 31 , wherein said hulled rice is microwave treated by a 1 to 10 cm layer thickness.  
   
   
       44 . Process according to  claim 31 , wherein said hulled rice is microwave treated by a 3 to 7 cm layer thickness.  
   
   
       45 . Process according to  claim 31 , wherein said hulled rice is treated continuously by 1.5 W/g microwave radiation for 1 to 6 minutes.  
   
   
       46 . Process according to  claim 45 , wherein said hulled rice is treated continuously for 3 minutes.  
   
   
       47 . Process according to  claim 31 , wherein said hulled rice is treated in an interrupted way by 1.5 W/g microwave radiation for 1 to 6 times, for 0.5 to 2 minutes, and between treatments there are 5 to 30 seconds breaks.  
   
   
       48 . Process according to  claim 47 , wherein said hulled rice is treated in an interrupted way for three times and between treatments there are 10 second breaks.  
   
   
       49 . Process according to  claim 31 , wherein said hulled rice is treated by 0.75 W/g microwave radiation for 1 to 4 minutes, and then by 1.5 W/g microwave radiation for 1 to 5 minutes.  
   
   
       50 . Process according to  claim 31 , wherein said hulled rice is treated by 0.3 W/g microwave radiation for 10 to 16 minutes.  
   
   
       51 . Process according to  claim 50 , wherein said hulled rice is treated for 10 to 12 minutes.  
   
   
       52 . Process according to  claim 31 , wherein said hulled rice is packed in a number of perforated bags and staged one above the other and are moved by means of a conveyor through said tunnel provided in said microwave furnace, and further comprising generating in the tunnel a special wet atmosphere of 85 to 99° C. in the surrounding of said rice bags.  
   
   
       53 . Process according to  claim 52 , wherein said special wet atmosphere has a temperature of from 90 to 95° C.  
   
   
       54 . Process according to  claim 52 , further comprising heating said hulled rice in the perforated bags to a temperature of 80 to 120° C.  
   
   
       55 . Process according to  claim 54 , wherein said hulled rice is at a temperature of from 105 to 108° C.  
   
   
       56 . Apparatus for the production of short cooking time rice comprising a microwave furnace, a tunnel in the microwave furnace, conveyor means for moving hulled rice packed into bags within the tunnel, said tunnel being provided with a top area element for collecting condensed water and steam, respectively, and the tunnel being provided with a bottom area element formed with apertures or with a perforation or with channels for distribution of any remaining condensed water and steam, respectively.  
   
   
       57 . Apparatus according to  claim 56 , wherein said tunnel is made from a material selected from the group consisting of ceramic material, plastic material, and quartz glass.  
   
   
       58 . Apparatus according to  claim 56 , wherein said top area element is formed in roof-like way and is angled or curved respectively semi-circular.  
   
   
       59 . Apparatus according to  claim 56 , wherein said top area element is provided with a means for collecting drops of condensed water or steam, respectively.  
   
   
       60 . Apparatus according to  claim 56 , wherein said top area element is provided with a cooling means for generating condensation.  
   
   
       61 . Apparatus according to  claim 56 , wherein a volume ratio of said tunnel and a volume of the rice packed in a number of bags is 3:1.  
   
   
       62 . Apparatus according to  claim 56 , wherein at least one of said tunnel and the microwave furnace is insulated to prevent heat losses.  
   
   
       63 . Apparatus according to  claim 56 , wherein said tunnel is equipped with an additional heating means.  
   
   
       64 . Apparatus according to  claim 63 , wherein said additional heating means comprises at least one heating element and/or hot air.  
   
   
       65 . Apparatus according to  claim 56 , wherein said tunnel is equipped with a channel system for heating medium for heating the tunnel.  
   
   
       66 . Apparatus according to  claim 65 , wherein said heating medium is hot air.  
   
   
       67 . Apparatus according to  claim 56 , wherein said microwave furnace is connected with a conduit means which is provided with a heat exchange means of a combustion engine which is connected with a generator provided for the generation of energy for the microwave furnace.  
   
   
       68 . Apparatus according to  claim 67 , wherein said conduit means is connected with a fan.  
   
   
       69 . Apparatus according to  claim 67 , wherein said conduit means is provided with a filter element.  
   
   
       70 . Apparatus according to  claim 69 , wherein a solar heat exchanger is used in lieu of said combustion engine.