Thermal relaxation and mechanical relaxation of rice gel

Abstract

Rice gel was prepared by simulating the production processes of Chinese local rice noodles, and the properties of thermal relaxation and mechanical relaxation during gelatinization were studied by differential scanning calorimetry (DSC) measurement and dynamic rheometer. The results show that during gelatinization, the molecular chains of rice starch undergo the thermal relaxation and mechanical relaxation. During the first heating and high temperature holding processes, the starch crystallites in the rice slurry melt, and the polymer chains stretch and interact, then viscoelastic gel forms. The cooling and low temperatures holding processes result in reinforced networks and decrease the viscoelasticity of the gel. During the second heating, the remaining starch crystallites further melt, the network is reinforced, and the viscoelasticity increases. The viscoelasticity, the molecular conformation and texture of the gel are adjusted by changing the temperature, and finally construct the gel with the textural characteristics of Chinese local rice noodle.

Keywords

rice gel / rheological properties / thermal relaxation / mechanical relaxation

References

[1] HormdokR., NoomhormA.. Hydrothermal treatments of rice starch for improvement of rice noodle quality[J]. Journal of Food Science and Technology, 2007, 40(10): 1723-1731

[2] LuZ. H., LiL. T., MinW. H., WangF., TatsumiE.. The effects of natural fermentation on the physical properties of rice flour and the rheological characteristics of rice noodles[J]. International Journal of Food Science and Technology, 2005, 40: 985-992

[3] FredrikssonaH., SilveriobJ., AndemonR., EliassonA. C., AmanP.. The influence of amylose and amylopectin characteristics on gelatinization and retrogradation properties of different starches[J]. Carbohydrate Polymers, 1998, 35: 119-132

[4] KeetelsJ. A. M., VlietT. V., WalstraP.. Gelation and retrogradation of concentrated starch systems (I): Gelation[J]. Food Hydrocolloids, 1996, 10: 343-353

[5] RingS. G.. Some studies on starch gelation[J]. Starch, 1985, 37: 80-83

[6] AhmedJ., RamaswamyH. S., AyadA., AlliI.. Thermal and dynamic rheology of insoluble starch from basmati rice[J]. Food Hydrocolloids, 2008, 22(3): 278-287

[7] NayoufM., LoiselC., DoubilierJ. L.. Effect of thermomechanical treatment on the rheological properties of crosslinked waxy corn starch[J]. Journal of Food Engineering, 2003, 59: 209-219

[8] RatnayakeW. S., JacksonD. S.. A new insight into the gelatinization process of native starches[J]. Carbohydrate Polymers, 2007, 67: 511-529

[9] HsuS., LuS., HuangC.. Viscoelastic changes of rice starch suspensions during gelatinization[J]. Food Chemistry and Toxicology, 2000, 65(2): 215-220

[10] ChenZ., SagisL., LeggerA., LinssenJ. P. H., ScholsH. A., VoragenA. G. J.. Evaluation of starch noodles made from three typical chinese sweet-potato starches[J]. Food Chemistry and Toxicology, 2002, 67(9): 3342-3347

[11] SinghN., SinghJ., SodhiN. S.. Morphological, thermal, rheological and noodle-making properties of potato and corn starch[J]. Journal of the Science of Food and Agriculture, 2002, 82: 1376-1383

[12] YoshidaH.. Relationship between enthalpy relaxation and dynamic mechanical relaxation of engineering plastics[J]. Thermochimica Acta, 1995, 266: 119-127

[13] LourdinD., ColonnaP., BrownseyG. J., NoelT. R., RingS. G.. Structural relaxation and physical ageing of starchy materials[J]. Carbohydrate Research, 2002, 337: 827-833

[14] American Association of Cereal Chemists. Approved methods of the AACC (10th Ed.). St.Paul, MN, 2000.

[15] MatveevY. I., SoestJ. J. G., NiemanC., WassermanL. A., ProtserovV. A., EzernitskajaM., YuryevV. P.. The relationship between thermodynamic and structural properties of low and high amylose maize starches[J]. Carbohydrate Polymers, 2001, 44(2): 151-160

[16] BrakeN. C., FennemaO. R.. Glass transition values of muscle tissue[J]. Journal of Food Science, 1999, 64(1): 10-15

[17] MesteM. L., ChampionD., RoudautG., BlondG., SimatosD.. Glass transition and food technology: A critical appraisal[J]. Journal of Food Science, 2002, 67(7): 2444-2458

[18] RoleeA., MesteM. L.. Thermomechanical behavior of concentration starch-water preparation[J]. Cereal Chemistry, 1997, 74(5): 581-588

[19] GunatatneA., HooverR.. Effect of heat-moisture treatment on the structure and physicochemical properties of tuber and root starches[J]. Carbohydrate Polymers, 2002, 49: 425-437

[20] HagenimanaA., PuP. P., DingX. L.. Study on thermal and rheological properties of native rice starches and their corresponding mixtures[J]. Food Research International, 2005, 38: 257-266

[21] TesterR. F., MorrisonW. R.. Swelling and gelatinization of cereal starches (I): Effects of amylopectin, amylose and lipids[J]. Cereal Chemistry, 1990, 67: 551-557