Histological Structures of Cooked Rice Grain

Ogawa, Yukiharu; Glenn, Gregory M.; Orts, William J.; Wood, Delilah F.

doi:10.1021/jf034758o

Cited by 80 publications

(49 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The examination of cross-sectional SEM micrographs showed that the gelatinized rice grain appeared to have a typical histological structure with cracks ( Figure 3A), as described by Dgawa et al (2003). Dgawa et al (2003) suggest that grain of cracks serve as channels for the flow of water into the grain during cooking.…”

Section: Internal Structure Of Gelatinized and Retrograded Rice Grainmentioning

confidence: 80%

“…As a main dietary source of carbohydrates, rice plays an important role in energy requirements and nutrient intake (Ramesh et al, 2000;Dgawa et al, 2003;Park et al, 2012). Contrary to other grains, rice is usually consumed as a whole grain for the main meal (Ramesh et al, 2000;Dgawa et al, 2003).…”

Section: Introductionmentioning

confidence: 99%

“…Contrary to other grains, rice is usually consumed as a whole grain for the main meal (Ramesh et al, 2000;Dgawa et al, 2003). With an increasing demand for pre-cooked rice products, starch retrogradation has become an important quality parameter for the evaluation of prolonged storage (Burgos & Armada, 2015;Yu et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

“…With an increasing demand for pre-cooked rice products, starch retrogradation has become an important quality parameter for the evaluation of prolonged storage (Burgos & Armada, 2015;Yu et al, 2010). The leached components which cover the surface of rice grain such as starch, nonstarch carbohydrates, lipids and proteins caused by cell disruption inside the granule during cooking process play significant roles in the eating quality of rice (Dgawa et al, 2003). The textural properties of cooked rice are primarily related to its moisture content because of starch gelatinization (Bello et al, 2007;Tamura & Dgawa, 2012;Kim et al, 2001;Ramesh et al, 2000).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Retrogradation of heat-gelatinized rice grain in sealed packaging: investigation of moisture relocation

Jung

Lee

et al. 2016

Food Sci. Technol

View full text Add to dashboard Cite

The aggregation of water molecules inside heat-gelatinized rice grain due to retrogradation of the grain was investigated by textural change and scanning electron microscopy (SEM) analysis of cooked grains after storage at 11 °C in a sealed package. Relaxation tests using a disc-type tip showed an increase in hardness (strength) of the cooked grain as the degree of retrogradation increased with increasing storage time, measured by the α-amylase-iodine method. SEM analysis of the vacuum-dried cooked rice grain showed a gradual increase in crevices, which further developed into holes at the center of the granule with increasing storage time. The results suggest that the disruption of hydrogen bonds between water and starch molecules is the first step for the retrogradation of gelatinized rice grain stored in a hermetic environment to avoid drying, resulting in its increased hardness, followed by the aggregation of starch molecules with subsequent water extrusion.Keywords: rice grain; starch; gelatinization; retrogradation; texture; structure.Practical Application: Retrogradation of gelatinized rice grain resulted in the loss of sensorial taste during storage.

show abstract

Section: Internal Structure Of Gelatinized and Retrograded Rice Grainmentioning

confidence: 80%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Retrogradation of heat-gelatinized rice grain in sealed packaging: investigation of moisture relocation

Jung

Lee

et al. 2016

Food Sci. Technol

View full text Add to dashboard Cite

show abstract

“…By definition, heterogeneous denotes variety and indicates nonuniformity. Ogawa et al (2003) showed that the morphology of the starch particles in the grain is made up of different sizes. Voids and microcracks also served as microchannels for moisture migration.…”

mentioning

confidence: 99%

Numerical Modeling of Heterogeneous Moisture Diffusion in Milled Rice Grains: Diffusion Coefficient as a Function of Moisture, Temperature and Time

Pérez

Tanaka

Hamanaka

et al. 2014

FSTR

View full text Add to dashboard Cite

The heterogeneous moisture diffusion of milled rice grains at 25, 35 and 45℃ was simulated in 3D using the finite element method. The objectives of the study were to investigate the effects of temperature on moisture absorption and to predict the heterogeneous moisture diffusion in milled rice grains. Major routes and cracks channeled and facilitated rapid moisture movement in the grain. High temperature increased the rate of moisture movement.The moisture diffusion coefficient expressed as a function of moisture, temperature and time adequately described the heterogeneous moisture diffusion characteristics in milled rice. The integration of the logistic function of time reduced the root mean square error (RMSE) values between the experimental data and the numerical solution.Moreover, the RMSE values were much lower than the values modeled with moisture and temperature only.Modeling moisture transfer using the major routes of moisture revealed an increase in the modified frequency factor of the moisture diffusion coefficient.Keywords: Heterogeneous moisture diffusion, milled rice, finite element modeling, diffusion coefficient, 3D modeling IntroductionThe cooking of rice is initiated by two concurrent processes: the hydration process and the heating process. The purpose of grain hydration is to bring the moisture within the grain to an appropriate level to cause partial disruption in the crystalline structure of the starch. On the other hand, heating raises the temperature to a sufficient level to gelatinize the starch granules. Whether the cooking of rice is done at home or commercially, these two processes are required. Usually, the cooking process requires a longer duration because the starch granules need time to become hydrated in order to be gelatinized (van den Doel et al., 2009).Thus, researchers and food processors alike are investigating ways to accelerate water uptake, thereby shortening the cooking time and reducing costs. Hence, this study aims to provide relevant data that will be useful in the design and optimization of the cooking of moisture with moving boundaries. Their findings revealed that the "differential" diffusion coefficient increased as the mean moisture content of rice increased with time. Perez et al. (2011) simulated the moisture diffusion and hygroscopic swelling in rice in three dimensions (3D) using Fick's or Fickian diffusion and Peleg's equation. The results of these studies were promising in understanding the hydration of rice. However, due to the complexity of grain geometry, which renders the diffusion process heterogeneous, it remains necessary to simulate the heterogeneous diffusion of moisture in milled rice in order to realistically reproduce the conditions occurring during moisture absorption. By definition, heterogeneous denotes variety and indicates nonuniformity. Ogawa et al. (2003) showed that the morphology of the starch particles in the grain is made up of different sizes. Voids and microcracks also served as microchannels for moisture migration.They also reported...

show abstract

Influence of bran layer on rice milling quality

Oppong Siaw,

McClung,

Mauromoustakos

et al. 2023

Cereal Chem

View full text Add to dashboard Cite

Background and objectivesRice milling involves applying forces to remove bran from brown rice to produce milled rice. The physical and chemical properties of a rice kernel may affect both the amount of bran removed during milling and the amount of head rice yield (HRY) produced which is a determinant of crop value. This study investigated bran thickness and bran chemical composition as factors that influence bran removal and HRY as a result of milling.FindingsThe results showed brown rice kernels with initial higher surface lipid contents (SLCs) required longer milling times to achieve 0.4% SLC, but the longer milling times did not translate into lower HRYs or higher bran yields. Bran chemical composition had a more significant impact on the milling characteristics than bran thickness. Arabinoxylans had the greatest impact on the HRY, followed by lipids and proteins.ConclusionsBran thickness did not have significant impact on the milling time, bran yield, nor HRY. There was significant interaction between arabinoxylans and proteins on HRY and bran yield, indicates the probability of crosslinking between proteins and arabinoxylans.Significance and noveltyThis study demonstrates the importance of rice bran chemical components and their interactions on rice milling quality, rather than their physical properties.This article is protected by copyright. All rights reserved.

show abstract

Histological Structures of Cooked Rice Grain

Cited by 80 publications

References 8 publications

Retrogradation of heat-gelatinized rice grain in sealed packaging: investigation of moisture relocation

Retrogradation of heat-gelatinized rice grain in sealed packaging: investigation of moisture relocation

Numerical Modeling of Heterogeneous Moisture Diffusion in Milled Rice Grains: Diffusion Coefficient as a Function of Moisture, Temperature and Time

Influence of bran layer on rice milling quality

Contact Info

Product

Resources

About