Physicochemical and Digestible Properties of Parboiled Black Rice With Different Amylose Contents

Abstract

The varieties of black rice with different amylose contents (waxy; medium-amylose: 16.03%; high-amylose: 27.14%) were parboiled and then evaluated for physicochemical and digestible properties. The color, crystalline structure, and swelling property of parboiled rice were analyzed, and the water molecular mobility, texture, and starch digestibility of cooked parboiled rice were determined. The color of black rice was only slightly changed after the parboiling treatment. The crystalline structures of waxy and medium-amylose rice were severely damaged by the parboiling treatment, while the highly crystalline structure was retained in parboiled high-amylose rice. During heating in water, parboiled high-amylose rice had a lower water absorption ratio (WAR) and volume expansion ratio (VER) than the other two varieties. After cooking, parboiled high-amylose rice had higher water molecular mobility and harder texture compared with the other two varieties. Cooked parboiled high-amylose rice contained higher content of resistant starch than cooked parboiled waxy and medium-amylose rice.

Parboiled Rice Processing Method, Rice Quality, Health Benefits, Environment, and Future Perspectives: A Review

“…The effect of parboiling increased RS and decreased RDS [7]. The RS and RDS concentrations of uncooked parboiled rice with a high level of amylose were significantly greater than those of waxy and medium-amylose varieties [92]. Unprocessed, uncooked rice has low starch resistance towards digestibility, whereas cooking rice increases starch digestibility.…”

Effect of processing methods and storage on the bioactive compounds of black rice (Oryza sativa L.): a review

“…In addition, nutrients such as vitamins and minerals in the rice cortex diffuse into the endosperm layer, improving the nutritional value of the polished rice. [123][124][125] At the same time, the parboiling process can kill bacteria and other microbes, inactivate the enzymes in the rice, and prolong the storage period of the product. 15 Therefore, researchers have extensively studied the physicochemical characteristics, nutritional components, and production processes of parboiled rice.…”

Rice Landrace Varieties and Fatty Acid Diversity: Profiling of Fatty Acid Variability of Parboiled and Un-parboiled Abakaliki Rice Landraces in Nigeria

“…Rice(Oryza sativa L.), one of the most significant grains in the world(Oryza sativa L.) is the second-most important crop after wheat and is a staple diet for more than 3 billion people (Zhang et al, 2022;Abbas et al, 2011). With a worldwide production of 645 million tons, rice is cultivated in at least 114 nations (IRRI, 2008).…”

“…The nutritional qualities of rice improve with parboiling due to the migration of vitamins and minerals towards the endosperm, as well as an increase in resistant starch (RS) content (Zohoun et al, 2018), which appears to offer considerable benefits to the human colon health (Nugent et al, 2005). Parboiling rice can increase its oxidative stability and extend its storage life (Koh and Surh, 2016;Zhang et al, 2022). In addition, by adding minerals and vitamins to the soaking water, parboiling can enrich rice with minerals and vitamins (Patindol et al, 2017;Jannasch & Wang, 2020).…”