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STRATEGIC R&D
เอกสารอ้างอิ ง/References
กฤษณพงศ์ ศรีพงษ์พั นธุ์กุล. แนวทางในการพัฒนาอุตสาหกรรมข้ าวไทย. กระทรวงเกษตรและสหกรณ์.
www.cpd.go.th. 2557.
Hibi Y, KitamuraS., KugeT. Effect of lipids on retrogradationof cooked rice. Cereal
Chemistry. 1990; 67(1): 7-10.
Kuzutani N. Theeffect of anti-agingof riceby “topbloomy” –emulsifiedoil for rice –. TopFood
TechnoFocus. 2010; 14: 10-15.
MaedaT,MatsuuraN, UtsunomiyaT, SitsujiandT,MoritaN. Effects of repeated
freezingand thawing treatments on retrogradationof starch in rice. 55th AustralianCereal
ChemistryConferenceandPacificRimSymposium. 2005.YuSF,MaY, TianD, SunDW.
Combinedeffects of freezingand storageconditions on the stalingof cooked rice. CIGR
XVIIthWorldCongress. 2010.
Kladsuk S, SirisomboonP. Determinationof hardness characteristicof cooked rice samples
in rice industry. The14th TSAENationalConferenceand the6th TSAE InternationalConference:
TSAE. 2013.
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andphysical attributes. Journal of Cereal Science. 2001; 33: 1-10.
Active Ingredientsfor ImprovingTexture
QualitiesofCookedRice
Rice is staple food for Asian people, and now gradually
expand to other regions. Recently, many Asian countries,
includingThailand,expect tomoveaway fromself-sufficiency
and become rice exporter over the next decades. This
situation of competition extremely brings down export
quantity and value of rice. To increase value per unit,
industriesmust process rice in various types, and price of
the treated product will goup ≥ 3 times.
Most popularoneof riceproduct iscooked ricebecause ready toeat
food (RTE:mainlycomposewithcooked rice) canservebusy lifestyleof
city people, and higher numbers of convenience store have responded
consumedemandof them. In thestoreshelf, refrigerator or freezer, it is
easy to find cooked ricewithmanyRTE recipes, for instance holy basil
chicken and grilled teriyaki sabawith cooked rice.
Qualitiesof cooked riceeasilychangeor deteriorateduringstorage,
particularlyat low temperature. Thesechangingqualitieswhich include
color, and texture, and other physicochemical properties. Texture of
fresh cooked rice, such as softness, is important factor on consumer
acceptance. Textureof cooked rice isstarting toughand rigidafter short
storageperiodbecauseof stalingor starch retrogradation. Main factors
influenceon thesephenomenaarecultivar,amylosecontent,andstorage
temperature (of cooked rice) which have been revealed by previous
researches. For example, many studies found storage temperature
-18°C (freeze)wasgreater than4°C (chill) to retardhardnessof cooked
rice. However, controlling theseparameters cannot givebest quality of
cooked rice, and adding food ingredients in cooking step is necessary
todevelop designable texture of product.
To improve quality texture of cooked rice, addition of some minor
ingredients is applied and interacted during heating. Oil application is
commonly used to keep softness of cooked rice for longtime. Sugar
and sugar alcohol are later groups which trehalose and sorbitol are
well-known. Both ingredients influence to reduce staling process of
cooked rice product at low temperature storage, resulting in shelf life
extension. Even if oil and sugar components can maintain soft and
sticky properties, better texture of cooked rice requires more potential
ingredients. Combinationsofemulsifierandoil, calledemulsifiedoil,are
greatest active ingredients nowadays.
Maincompositionof ricegranule isstarch (normal content>75%)
which is basically heated in excess water and completely cooked
(gelatinization). Addingsmallamountofactive ingredients, theswollen
granulewillabsorb thedispersedagents (active ingredientswithwater)
duringgelatinization. Thus,stalingofcooked ricehasbeenprevented
by the ingredients, causinggoodwaterholdingcapacityandpleasant
texture. Amongofemulsifiers,glycerolesterof fattyacid,polyglycerol
ester of fattyacid, lecithinareeffectiveactive ingredients formaintain
softnessandstickinessofcooked rice.Moreover,scientific researches
indicated thatusesofmixedvegetableoiland theemulsifierseffectively
improve texture qualities of cooked rice. The studies revealed that
textureof cooked ricewithemulsifiedoil additionsignificantlyshowed
higher valueof sensoryacceptance thannoadditive (control sample)
and sugar treatments. Consequently, cooked rice products need
special formulaof emulsifiedoil mixture for achievingperfect texture
along storage time.