• Title, Summary, Keyword: pasting property

Search Result 65, Processing Time 0.036 seconds

Effect of Ohmic Heating on Pasting Property of Starches (옴가열이 전분의 Pasting 특성에 미치는 영향)

  • Cha, Yun-Hwan
    • The Korean Journal of Food And Nutrition
    • /
    • v.30 no.4
    • /
    • pp.689-695
    • /
    • 2017
  • Ohmic heating is an internal heating method based on the principle that when an electrical current passes through food, electric resistance heat is uniformly generated internally by food resistance. Previous studies indicate that the thermal properties, external structure, internal structure, and swelling power of ohmic heat treated starch of various starches, such as potato, wheat, corn, and sweet potato, differed from those of conventional heating at the same temperature. In this study, the pasting property of starch, treated with ohmic and conventional heating, were measured by RVA (Rapid Visco-Analyzer). Our results show that as the ohmic heating temperature increased, the PV (Paste Viscosity) of the starch decreased significantly, and the PT (Pasting Temperature) increased. Changes in PV and PT indicate that the swelling of starch remains unchanged by ohm heating. The HPV (Hot Paste Viscosity), CPV (Cold Paste Viscosity) and SV (Setback Viscosity) of ohmic heated starch also differed from the conventional heated starch. The pasting property is similar to the viscosity curve of common cross-linked modified starch. In this experiment, we further confirm the similarity with modified starch and its usability.

Rheological and Pasting Properties of Naked Barley Flour as Modified by Guar, Xanthan, and Locust Bean Gums

  • Yoon, Sung-Jin;Lee, Youngseung;Yoo, Byoungseung
    • Preventive Nutrition and Food Science
    • /
    • v.21 no.4
    • /
    • pp.367-372
    • /
    • 2016
  • To understand the effects of adding different gums (guar, xanthan, and locust bean gums) on naked barley flour (NBF), the rheological and pasting properties of NBF-gum mixtures were measured at different gum concentrations (0, 0.3, and 0.6% w/w). Steady shear rheological properties were determined by rheological parameters for power law and Casson models. All samples showed a clear trend of shear-thinning behavior (n=0.16~0.48) and had a non-Newtonian nature with yield stress. Consistency index, apparent viscosity, and yield stress values increased with an increase in gum concentration. Storage modulus values were more predominant than loss modulus values with all concentrations of gums. There is a more pronounced synergistic effect of elastic properties of NBF in the presence of xanthan gum. Rapid visco analyser pasting properties showed that the addition of gums resulted in a significant increase in the peak, breakdown, setback, and final viscosities, whereas the pasting temperature decreased.

Changes in pasting properties and free fatty acids of different brown rice cultivar during storage

  • Choi, Induck;Kwak, Jieun;Yoon, Mi-Ra;Chun, Areum;Choi, Dong-Soo
    • Korean Journal of Food Preservation
    • /
    • v.24 no.4
    • /
    • pp.491-496
    • /
    • 2017
  • Paddy rice is typically stored during postharvest until rice grain is processed into brown rice and milled rice by hulling and milling procedure, respectively. Recently, instead of storing paddy rice, storage of brown rice has been in the spotlight because it is more convenient and economically feasible. Different brown rice cultivars with varying amylose contents including waxy rice, medium-waxy rice, and non-glutinous rice were stored in room temperature storage for four months, and the changes in grain qualities of brown rice were evaluated. Amylose content significantly affected pasting properties in which rice cultivar with higher amylose content showed longer pasting time and higher peak viscosity. Storage also affected pasting viscosities, showing an increase in peak viscosity, but a decrease in breakdown viscosity. The changes in pasting viscosity during storage could be an important starch property for aged brown rice utilization. Waxy brown rice showed the weakest aging property in terms of free fatty acids (FFA) accumulation, whereas non-glutinous rice was more substantial grain quality against aging. The FFA values of two months storage were not significantly different from the initial FFA contents, suggesting that brown rice stored in room temperature for two months could be feasible for direct consumption of brown rice.

Pasting Properties of Crude ${\beta}-Glucan$ from Spent Brewer's Yeast on Wheat Flour and Starch

  • Yoo, Moon-Sik;Lee, Young-Tack
    • Food Science and Biotechnology
    • /
    • v.16 no.3
    • /
    • pp.485-488
    • /
    • 2007
  • Plentiful amount of spent yeast has been produced as a by-product from breweries. ${\beta}-Glucan$ was prepared from the spent brewer's yeast in a crude form with hot water extraction and subsequent enzymatic treatment. The crude ${\beta}-glucan$ preparation consisted of mainly glucan (53% of total wt), containing approximately 35% ${\beta}-glucan$ content of total weight. The effects of crude ${\beta}-glucan$ substitution (1-9%) on pasting properties of wheat flour and starch were determined using a Rapid Visco-Analyzer (RVA). Incorporation of yeast ${\beta}-glucan$ into wheat flour and starch significantly decreased peak and [mal viscosities, but slightly increased setback viscosity. The setback viscosity was considerably higher in starch/${\beta}-glucan$ suspension than in flour/${\beta}-glucan$ suspension. It was suggested that preparation of yeast ${\beta}-glucan$ into aqueous dispersion might affect pasting behaviors of wheat flour and starch.

Effects of Extrusion Conditions on Pasting Properties of Potato

  • Cha, Jae-Yoon;Ng, Perry K.W.;Shin, Han-Seung;Cash, Jerry
    • Food Science and Biotechnology
    • /
    • v.16 no.5
    • /
    • pp.783-788
    • /
    • 2007
  • An advantage to the extrusion of raw potatoes is a reduction in the energy input required to process potato products; however, the effects of extrusion on the properties of raw potato have not been studied. The purposes of this study were to develop a workable extrusion process for raw potato and to study the effects of extrusion conditions on the pasting properties of extruded potato products. The peak viscosity, final viscosity, pasting temperature, water solubility index, and water absorption index of pressed and pressed-dried potato extrudates decreased as die exit temperature increased, whereas they did not change as screw speed increased. The peak viscosity, final viscosity, and water solubility of steam-cooked potato products decreased with extrusion processing; however, they did not change with increasing die exit temperature and screw speed. Potato products with different degrees of depolymerization of extruded potato starch, depending on die exit temperature, were produced from raw potatoes.

Textural Properties of Processed Foods Produced from Newly Developed Non-Glutinous Rice Cultivars

  • Ha, Mi-Sun;Roh, Yi-Woo;Hong, Kwon-Pyo;Kang, Yoon-Suk;Jung, Dong-Chae;Kim, Kwang-Ho;Park, Sang-Kyu;Ha, Sang-Do;Bae, Dong-Ho
    • Food Science and Biotechnology
    • /
    • v.16 no.5
    • /
    • pp.789-795
    • /
    • 2007
  • This study was undertaken to investigate the producibility of processed foods utilizing 6 newly developed non-glutinous rice cultivars. First, cooked rice, cake, cookies, bread, and slender rice cake sticks were prepared with the newly developed cultivars; then their physicochemical and textural properties were evaluated. The rice samples had similar pasting temperatures and peak times, but different viscosities and other pasting properties. The textural analysis results suggested that 'Chucheong' was appropriate for cooked rice due to its low amylose content; hardness, and springiness; 'Ilphumbyeo' for rice cakes due to its high amylose content, moderate cohesiveness and adhesiveness, and low hardness; 'Ilphumbyeo' for cookies due to its high amount of protein, and low cohesiveness and adhesiveness; 'Ilphumbyeo' for bread due to its high amylose content, moderate hardness, and low consistency; and 'Ilphumbyeo' for the slender rice cake sticks due to its low hardness, moderate breakdown, paste viscosity, and setback.

Changes in Pasting and Fluid Properties of Corn and Rice Starches after Physical Modification by Planetary Mill

  • Kim, Bum-Keun;Lee, Jun-Soo;Cho, Yong-Jin;Park, Dong-June
    • Food Science and Biotechnology
    • /
    • v.17 no.4
    • /
    • pp.814-818
    • /
    • 2008
  • Com and rice starches were physically modified by planetary mill. While native starches showed high peak viscosities (1,001 and 563 cp), it decreased largely (42 and 20 cp for rice and com starch, respectively) after 2 hr of physical modification. When two starches were co-ground, peak viscosities decreased more largely than single ground one only in 30 min, indicating the pasting properties could be easily changed by co-grinding. Especially, the higher the amount of com starch, the viscosity decreased more largely, which means that paste stability could be controlled also by changing the ratio of com and rice starch. Mean particle size increased with physical modification time since particles became spread because of shear force. There were also changes in surface morphology after physical modification. Fluid property, such as mean time to avalanche (MTA), was improved (from $6.16{\pm}0.47$ and $8.37{\pm}1.23\;sec$ to $5.47{\pm}0.78$ and $5.26{\pm}1.37\;sec$ for rice and com starch, respectively) by physical modification. Pasting property, such as swelling power, was also improved by physical modification. These mean that native starches can be applied to both conventional powder and new paste-food industry more efficiently by physical modification.

Evaluation of Molecular Weight Distribution, Pasting and Functional Properties, and Enzyme Resistant Starch Content of Acid-modified Corn Starches

  • Koksel, Hamit;Ozturk, Serpil;Kahraman, Kevser;Basman, Arzu;Ozbas, Ozen Ozboy;Ryu, Gi-Hyung
    • Food Science and Biotechnology
    • /
    • v.17 no.4
    • /
    • pp.755-760
    • /
    • 2008
  • The aim of this study was to produce resistant starch preparations from acid-modified com starches prepared at various hydrolysis levels (0.5-4.0 hr). Effect of autoclaving cycles on resistant starch (RS) formation was investigated. Molecular weight distribution, pasting and functional properties of acid-modified com starches were determined. For RS formation native and acid-modified starch samples were gelatinized and autoclaved (1 or 2 cycles). While native and acid-modified starches did not contain any RS, the levels increased to 9.0-13.5% as a result of storage at $95^{\circ}C$ after first autoclaving cycle. Second autoclaving cycle together with storage at $95^{\circ}C$ brought final RS contents of the samples incubated at 4 and $95^{\circ}C$ after the first cycle to comparable level. As acid modification level increased, the amount of high molecular weight fractions decreased, resulting in significant decreases in viscosities (p<0.05). The samples produced in this study had low emulsion stability and capacity values.

Physicochemical Properties of Starch Affected by Molecular Composition and Structures: A Review

  • Srichuwong, Sathaporn;Jane, Jay-Iin
    • Food Science and Biotechnology
    • /
    • v.16 no.5
    • /
    • pp.663-674
    • /
    • 2007
  • Starches from different botanical sources differ in the ratio of amylose to amylopectin contents, molecular structures of amylose and amylopectin, granule morphology, and minor-component contents. These structural features result in different gelatinization, pasting, retrogradation properties, and enzyme digestibility of starch granules. In this review, compositions and molecular structures of starches and their effects on the physicochemical properties are summarized and discussed.

Effect of Microwave Irradiation on Crystallinity and Pasting Viscosity of Corn Starches Different in Amylose Content

  • Lee, Su-Jin;Sandhu, Kawaljit Singh;Lim, Seung-Taik
    • Food Science and Biotechnology
    • /
    • v.16 no.5
    • /
    • pp.832-835
    • /
    • 2007
  • Moisture content of normal, waxy, and high amylose com starches was adjusted to 10-35%, and irradiated in a microwave oven. The effect of microwave irradiation on the crystalline structure of starch was measured by using a differential scanning calorimetry (DSC), and X-ray diffractometry. Pasting viscosity profile was also determined by using a rapid viscoanalyzer (RVA). For all the 3 types of starches tested, the rate of temperature increase by the microwave irradiation was faster and more rapidly reached the maximum temperature of the pressure bomb ($120^{\circ}C$) when the moisture content was higher. X-ray diffraction and DSC data revealed that the microwave irradiated starch underwent partial disruption of crystalline structure. RVA studies showed that the irradiation caused significant reductions in maximal viscosity and breakdown, whereas pasting temperature was increased. Overall trends revealed that the microwave irradiation on the starch containing limited moisture content (less than 35%) provided the effects similar to the heat moisture treatment. These effects became more significant when the moisture content was higher. Compared to waxy com starch, normal, and high amylose com starches appeared to be more susceptible to the microwave irradiation.