Profile of phenolic compounds and antioxidant activity of finger millet varieties.

Obesity and chronic diet-related diseases such as type 2 diabetes, hypertension, cardiovascular disease, cancers, and celiac are increasing worldwide. The increasing prevalence of these diseases has led nutritionists and food scientists to pay more attention to the relationship between diet and different disease risks. Among different foods, rice has received increasing attention because it is a major component of billions of peoples' diets throughout the world. Rice is commonly consumed after polishing or whitening and the polished grain is known a high glycemic food because of its high starch content. In addition, the removal of the outer bran layer during rice milling results in a loss of nutrients, dietary fiber, and bioactive components. Therefore, many studies were performed to investigate the potential health benefits for the consumption of whole brown rice (BR) grain in comparison to the milled or white rice (WR). The objective of this work was to review the recent advances in research performed for purposes of evaluation of nutritional value and potential health benefits of the whole BR grain. Studies carried out for purposes of developing BR-based food products are reviewed. BR safety and preservation treatments are also explored. In addition, economic and environmental benefits for the consumption of whole BR instead of the polished or WR are presented. Furthermore, challenges facing the commercialization of BR and future perspectives to promote its utilization as food are discussed.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/1541-4337.12449

Brown Rice Versus White Rice: Nutritional Quality, Potential Health Benefits, Development of Food Products, and Preservation Technologies.

Whole grain foods have been promoted to be included as one of the important components of a healthy diet because of the relationship between the regular consumption of whole-grain foods and reduced risk of chronic diseases. Rice is a staple food, which has been widely consumed for centuries by many Asian countries. Studies have suggested that brown rice is associated with a wide spectrum of nutrigenomic implications such as anti-diabetic, anti-cholesterol, cardioprotective and antioxidant. This is because of the presence of various phytochemicals that are mainly located in bran layers of brown rice. Therefore, this paper is a review of publications that focuses on the bioactive compounds and nutrigenomic implications of brown rice. Although current evidence supports the fact that the consumption of brown rice is beneficial for health, these studies are heterogeneous in terms of their brown rice samples used and population groups, which cause the evaluation to be difficult. Future clinical studies should focus on the screening of individual bioactive compounds in brown rice with reference to their nutrigenomic implications.

Phytochemical Profile of Brown Rice and Its Nutrigenomic Implications

Free and bound phenolic profiles of the bran from different rice varieties and their antioxidant activity and inhibitory effects on ɑ-amylose and ɑ-glucosidase

Cereal grains are a major source of human food and their production has steadily been increased during the last several decades to meet the demand of our increasing world population. The modernized society and the expansion of the cereal food industry created a need for highly efficient processing technologies, especially flour production. Earlier scientific research efforts have led to the invention of the modern steel roller mill, and the refined flour of wheat has become a basic component in most of cereal-based foods such as breads and pastries because of the unique functionality of wheat protein. On the other hand, epidemiological studies have found that consumption of whole cereal grains was health beneficial. The health benefit of whole cereal grain is attributed to the combined effects of micronutrients, phytochemicals, and dietary fibre, which are mainly located in the outer bran layer and the germ. However, the removal of bran and germ from cereal grains during polishing and milling results in refined flour and food products with lower bioactive compounds and dietary fibre contents than those from whole grain. Also, the level of bioactive compounds in cereal food is influenced by other food preparation procedures such as baking, cooking, extrusion, and puffing. Therefore, food scientists and nutritionists are searching for strategies and processing technologies to enhance the content and bioavailability of nutrients, bioactive compounds, and dietary fibre of cereal foods. The objective of this article was to review the research advances on technologies for the enhancement of bioactive compounds and dietary fibre contents of cereal and cereal-based foods. Bioactivities or biological effects of enhanced cereal and cereal-based foods are presented. Challenges facing the application of the proposed technologies in the food industry are also discussed.

Technologies for enhancement of bioactive components and potential health benefits of cereal and cereal-based foods: Research advances and application challenges

Phytochemical profiles and antioxidant activity of brown rice varieties

Structural Characteristics of Cooked Black Rice Influenced by Different Stabilization Treatments and Their Effect Mechanism on the In Vitro Digestibility

The peroxidase in black rice was inactivated by superheated steam (SS), far infrared radiation (FIR), and microwave treatment (Mw) respectively, and then their effects on the physicochemical and nutritional properties of black rice were compared. Results showed that SS, FIR, and Mw completely inactivated peroxidase with minimum time of 16 min, 8 min, 480 s, respectively. FIR and Mw significantly decreased all pasting viscosities and gelatinization enthalpy (ΔH), while SS increased most pasting viscosities and showed almost no influence on ΔH. Besides, black rice stabilized by SS rather than FIR and Mw showed similar cooking and sensory quality and microscopic structure to that of raw black rice. Furthermore, SS was more favorable to retain the phenolics, flavonoids, anthocyanins and antioxidant capacity than FIR and Mw. These results suggested that SS was most suitable to improve the shelf life of black rice with minimal damages to its physicochemical and nutritional properties. 

Comparative study on physicochemical and nutritional properties of black rice influenced by superheated steam, far infrared radiation, and microwave treatment

Dielectric barrier discharge cold plasma (DBD-CP) was applied to brown rice either in the form of whole brown rice or in brown rice powder in order to inactivate peroxidase. Afterwards, the DBD-CP stabilized whole brown rice (CPR) and brown rice powder (CPP) were compared through their storage, physicochemical and bioactive properties. Results demonstrated that peroxidase was completely inactivated in CPP rather than in CPR, and the fat acidity in CPP was significantly lower than that in CPR and raw brown rice during accelerated storage. Besides, the etching effect of DBD-CP induced many scorched spots and micropores respectively in the surface of CPR and CPP, which significantly increased their water absorption index and pasting viscosities. Specially, the starch and protein molecules were depolymerized in CPR, while they were cross-linked in CPP. Consequently, the effects of DBD-CP on gelatinization enthalpy, setback value and water solubility index differed in CPR and CPP. Furthermore, CPR was better for the retainment of phenolic compounds and antioxidant activity than CPP. Therefore, DBD-CP was useful to improve the shelf life of brown rice, and its effects on the storage, physicochemical and bioactive properties were highly depended on the form of brown rice to be processed. 

Peroxidase inactivation by cold plasma and its effects on the storage, physicochemical and bioactive properties of brown rice

The effects of co-addition of three plant peptides (P)—soybean peptide (SP), wheat peptide (WP) or corn peptide (CP), and lauric acid (LA)—on the physicochemical properties and in vitro digestibility of sweet potato starch (SPS) are investigated. The enthalpy (ΔH2), complex index (CI), ordered crystalline structure, and resistant starch (RS) content of the SPS–LA–P ternary system significantly increase, compared to those of the SPS–P and SPS–LA binary systems. The microscopic surface is smoother and denser, and the cross-sectional gel layer is thicker. The peak viscosity, breakdown value, paste clarity, and gel hardness of the ternary system also significantly decrease, likely due to the formation of more SPS–LA binary complexes and SPS–LA–P ternary complexes in the ternary systems. The co-addition of WP and LA demonstrates the most significant increase in the ΔH2 (1.48 J g−1), CI (48.74%), relative crystallinity (18.17%), and molecular orderliness of SPS–control, which also has reduced paste clarity (23.93%). The addition of SP and LA is most effective in reducing the peak viscosity (4183.33 cP) and gel hardness (221.72 g) of SPS, and the ternary systems containing WP and CP have the highest RS content of 29.81% and 28.74%, respectively. 

Zi Cong Zeng

Papers

Phytochemical profiles and antioxidant activity of brown rice varieties

Structural Characteristics of Cooked Black Rice Influenced by Different Stabilization Treatments and Their Effect Mechanism on the In Vitro Digestibility

Comparative study on physicochemical and nutritional properties of black rice influenced by superheated steam, far infrared radiation, and microwave treatment

Peroxidase inactivation by cold plasma and its effects on the storage, physicochemical and bioactive properties of brown rice

Effects of co‐addition of plant peptides and lauric acid on the physicochemical properties and in vitro digestibility of sweet potato starch