Effect of oral processing on texture, rheology properties, and microstructure of three rice varieties

AbstractThis research explored the impact of in-vivo oral processing on the bolus properties of three rice varieties [white ponni (WP), mappillai samba (MS), and basmati (B)] that were selected based on variations in the amylose content. The amylose and dry matter content of the WP, MS, and B were 4.67, 7.48, and 13.8(%) and 69.57, 60.09, and 70.47(%), respectively. Mastication features (bite-size, chewing time, and chew cycles), bolus properties (particle size distribution, bolus moisture content, rheology, and starch hydrolysis), time-dependent bolus features (rate of incorporation of saliva and saliva content) and, temporal dominance of sensation (TDS) of cooked rice were studied. Results confirmed the significance of oral processing on various bolus characteristics. Moreover, a pronounced correlation between the morphology of rice varieties and mastication features was observed. The structure and textural characteristics of the different rice varieties (MS, WP, B) showed considerable effects on the consumption time (25.7 s, 22.2 s, 17.8 s) and chewing cycles (34, 31, 23). Rate of saliva incorporation was relatively lesser for MS as compared with WP and B. Solid loss followed the trends WP > MS > B. The total starch content of cooked rice boluseswas WP (82.69 ± 0.01%), MS (79.49 ± 0.01%), and B (71.74 ± 0.01%). Further, texture – TDS and flavor – TDS of all varieties were found to be strongly dependent on textural attributes, composition, and oro-sensory perception. This study provides a significant understanding of the oral processing behavior of rice and its bolus, considering the effect of variations in amylose content, texture, and morphology.

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Impact of Oral Mastication on the in vitro Digestibility of Pigmented and Non-Pigmented Rice Varieties

Biointerface Research in Applied Chemistry ◽

10.33263/briac121.11481160 ◽

2021 ◽

Vol 12 (1) ◽

pp. 1148-1160

Keyword(s):

Amylose Content ◽

Starch Content ◽

In Vitro Digestion ◽

In Vitro Digestibility ◽

Rice Varieties ◽

Pigmented Rice ◽

Rice Samples ◽

Oral Processing

The extent of starch hydrolysis and glycemic index (GI) of foods depends on how it is orally processed, but many in vitro digestion studies failed to consider the oral phase of digestion. This research aimed to understand the relationship between oral mastication and GI of rice. For this study, different rice varieties (pigmented and non-pigmented) were selected and analyzed for their physicochemical properties. The amylose content for all rice varieties was higher than 25%, with the starch content of 68.68 ± 0.70% - 81.60 ± 1.78%. Temporal dominance of sensation was determined for rice samples to understand the consumers' sensory preferences towards the pigmented rice varieties. In vivo oral mastication studies were also performed for the rice varieties, in which significant differences were observed amongst pigmented and non-pigmented rice samples. The particle size for pigmented rice varieties after in vivo oral mastication was significantly larger (50% particles greater than 2 mm; due to its intact morphology) than non-pigmented rice. The significant impact of oral processing on the GI of rice irrespective of the varieties was also observed in this study. Thus, this research sheds light on the need for oral processing for in vitro digestion studies.

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On the Germination of Seeds of Rice Varieties at Low Temperatures : Preliminary

Japanese Journal of Crop Science ◽

10.1626/jcs.2.263 ◽

1930 ◽

Vol 2 (4) ◽

pp. 263-268 ◽

Cited By ~ 1

Author(s):

KIYOKATSU MATSUDA

Keyword(s):

Low Temperatures ◽

Rice Varieties

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Studies on the yield abilities of the rice varieties in Japan : Continued

Japanese Journal of Crop Science ◽

10.1626/jcs.17.17 ◽

1948 ◽

Vol 17 (1) ◽

pp. 17-20 ◽

Cited By ~ 1

Author(s):

Isamu Morimoto

Keyword(s):

Rice Varieties

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Glycaemic responses to glucose and rice in people of Chinese and European ethnicity

10.26686/wgtn.12831854 ◽

2020 ◽

Author(s):

M Kataoka ◽

BJ Venn ◽

SM Williams ◽

Lisa Te Morenga ◽

IM Heemels ◽

...

Keyword(s):

Ethnic Differences ◽

Rice Variety ◽

Glycaemic Index ◽

Activity Levels ◽

Glycaemic Response ◽

Rice Varieties ◽

Adjusted Risk ◽

Postprandial Glycaemia ◽

Adjusted Risk Ratio ◽

Glucose Curve

Aims: Diabetes rates are especially high in China. Risk of Type 2 diabetes increases with high intakes of white rice, a staple food of Chinese people. Ethnic differences in postprandial glycaemia have been reported. We compared glycaemic responses to glucose and five rice varieties in people of European and Chinese ethnicity and examined possible determinants of ethnic differences in postprandial glycaemia. Methods: Self-identified Chinese (n = 32) and European (n = 31) healthy volunteers attended on eight occasions for studies following ingestion of glucose and jasmine, basmati, brown, Doongara® and parboiled rice. In addition to measuring glycaemic response, we investigated physical activity levels, extent of chewing of rice and salivary α-amylase activity to determine whether these measures explained any differences in postprandial glycaemia. Results: Glycaemic response, measured by incremental area under the glucose curve, was over 60% greater for the five rice varieties (P < 0.001) and 39% greater for glucose (P < 0.004) amongst Chinese compared with Europeans. The calculated glycaemic index was approximately 20% greater for rice varieties other than basmati (P = 0.01 to 0.05). Ethnicity [adjusted risk ratio 1.4 (1.2-1.8) P < 0.001] and rice variety were the only important determinants of incremental area under the glucose curve. Conclusions: Glycaemic responses following ingestion of glucose and several rice varieties are appreciably greater in Chinese compared with Europeans, suggesting the need to review recommendations regarding dietary carbohydrate amongst rice-eating populations at high risk of diabetes. © 2012 Diabetes UK.

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