Location: Functional Foods Research Unit
Title: Particle size fractionation of high-amylose rice (Goami 2) flour as an oil barrier in a batter-coated fried system Authors
|Lee, Seung Mi -|
|Yoo, Jiyoung -|
|Lee, Suyong -|
Submitted to: Food and Bioprocess Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 25, 2011
Publication Date: November 10, 2011
Citation: Lee, S.M., Yoo, J., Inglett, G.E., Lee, S. 2013. Particle size fractionation of high-amylose rice (Goami 2) flour as an oil barrier in a batter-coated fried system. Food and Bioprocess Technology. 6:726-733. Interpretive Summary: High amylose rice flour that is called Goami 2 was separated into four fractions with different particle sizes and incorporated into the frying batter formulation as an oil barrier in fried foods. The use of the rice flour with smaller particle size produced batters with high viscosity and elasticity which resulted in increased batter pickup and specific gravity. This study could contribute to the extensive use of rice flour in a wider variety of food products as a functional ingredient beyond the traditional staple diet in the form of boiled and cooked rice. In addition, since rice flour is gluten-free, the replacement of wheat flour with rice flour would be good for individuals with celiac disease to enjoy reduced gluten fried foods. These results will benefit health concerned consumers and batter processors by providing a method to decrease the oil uptake of batters during frying so consumers will consume less fat in their diet.
Technical Abstract: The particle size effects of high-amylose rice (Goami 2) flour on quality attributes of frying batters were characterized in terms of physicochemical, rheological, and oil-resisting properties. High-amylose rice flours were fractionated into four fractions (70, 198, 256, and 415 µm) of which morphology was also analyzed by scanning electron microscopy. Rice flour with smaller particle size exhibited a higher degree of starch gelatinization, giving rise to increased pasting parameters. When the rice flours were incorporated into frying batters, higher steady shear viscosity was observed in the batters with finer rice flour, which could be well characterized by the power law model. In addition, the dynamic viscoelastic properties of the batters were enhanced by the use of rice flour with smaller particle size, which also caused an increase in batter pickup. When subjected to deep fat frying, the batters with finer rice flour exhibited reduced moisture loss. Furthermore, the oil uptake was found to have a positive correlation with the particle size of rice flour (R^2^=0.88), even showing the reduction of oil uptake by 15%. It could be synergistically attributed to the formation of outer starch granular layers, high batter viscosity/pickup, and reduced moisture loss by finer rice flour.