| Author | Hatairat Kitprasong |
| Call Number | AIT Thesis no.FB-04-07 |
| Subject(s) | Quick-cooking rice
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. FB-04-07 |
| Abstract | Low amylose broken rice, Khao Dawk Mali (KDML 105), was used as raw material
for production of extruded quick cooking rice. The effect of operating conditions of single
screw extrusion on cooking and eating quality of extruded rice was investigated. The second
zone banel temperature and die temperature were varied from 70-90°C and 60-70°C,
respectively. Moreover, the proper drying temperature after extrusion and water-to-rice ratio
for cooking were also determined. To improve quality of extruded rice, cross-linked and
pregelatinized modified starch coated on the extruded rice kernel and by mixing with the
broken rice before extrusion. The fortification of extruded rice by calcium was done and
compared with milled rice and pre-heated quick cooking rice. The acceptability of foi1ified
extruded rice also was determined.
The operating condition had no affect on cooking time and hardness. By increasing
banel temperature, better cooking quality of extruded rice was observed due to decrease in
total solid loss and water uptake. The exh·usion caused color more yellow but it was
acceptable. Die temperature did not affect cooking and eating quality. All extruded rice need
to be cooked for 10-11 minutes which can classify as "quick cooking rice". By instrumental
method, the water-to-rice ratio 1.4 provided the hardness value close to hardness of KDML
105 milled rice whereas panelists prefened 1.2 water-to-rice ratios. The quality of extruded
rice was better at 40°C drying temperature after extrusion. Drying temperature was not
affected on color, cooking time, and texture of cooked rice. For addition of modified starch,
cooking time was increased to 12-13 minutes in both methods. Coating provided less
brightness, yellowness, and whiteness. The total solid loss increased and water uptake
decreased with the increase in modified starch content whereas cooking time and hardness
were not influenced. From senso1y evaluation, 1 % starch coating obtained the highest scores
in all attributes that agreed with the good results of cooking quality. For addition of modified
starch before extrusion, the total solid loss and water uptake decreased whereas hardness was
markedly increased as the percentage of coating increased. 3% addition of modified starch
showed the best cooking quality but 1 % addition of modified starch gave the highest score by
panelist in terms of texture and hardness. It was concluded that 1 % addition was the best
among all starch treatment. 1 % starch coating can improve the quality of extruded rice in
terms of appearance whereas 1 % addition improved the texture of cooked extruded rice.
Fortification with calcium caused fissuring of grain after drying whereas addition of 1 %
modified starch with calcium reduced fissuring. However, the acceptability of extruded rice
was acceptable. |
| Year | 2004 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. FB-04-07 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Athapol Noomhorm |
| Examination Committee(s) | Jindal, Vinod.K.;
Rakshit, Sudip. K. |
| Scholarship Donor(s) | Royal Thai Government Fellowship |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2004 |