Parboiling improved oxidative stability of milled white rice during one-year storage

Evaluation of rice bran varieties and heat treatment for the development of protein/starch-based bioplastics via injection molding

Improper management of disposable plastics and resource depletion pose significant environmental challenges, prompting interest in alternatives like bioplastics. These novel materials can be produced from by-products of the agro-food industry, offering solutions and valorizing waste. Rice bran, a substantial by-product of rice processing, is abundant and cost-effective, rich in proteins and starch. These components can be transformed into industrial-grade bioplastics through proper processing. This study evaluates the impact of rice bran varieties and thermal treatment during processing on bioplastic development for injection molding. After defatting and sieving, rice bran was mixed with glycerol and subjected to injection molding at 150 °C. Results indicate that parboiled systems, especially from japonica rice bran, showed high viscoelastic moduli and tensile strength. These systems exhibited a denser structure, resulting in lower water absorption. This research sheds light on the connection between rice bran variety, heat treatment, and the final properties of derived bioplastics. This research contributes significantly to understand the relationship between the variety of rice bran and the impact of heat treatment on the ultimate properties of the derived bioplastics.

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

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.

Research advance in gas detection of volatile organic compounds released in rice quality deterioration process

Rice quality deterioration will cause grievous waste of stored grain and various food safety problems. Gas detection of volatile organic compounds (VOCs) produced by deterioration is a nondestructive detection method to judge rice quality and alleviate rice spoilage. This review discussed the research advance of VOCs detection in terms of nondestructive detection methods of rice quality deterioration, applications of VOCs in grain detection, inspection of characteristic gas produced during rice spoilage, rice deterioration prevention and control, and detection of VOCs released by rice mildew and insect attack. According to the main causes of rice quality deterioration and major sources of VOCs with off-odor generated during rice storage, deterioration can be divided into mold and insect infection. The results of literature manifested that researches mainly focused on the infection of Aspergillus in the mildew process and the attack of certain pests in recent years, thus the research scope was limited. In this paper, the gas detection methods combined with the chemometrics to qualitatively analyze the VOCs, as well as the correlation with the number of colonies and insects were further studied based on the common dominant strains during rice mildew, that is, Aspergillus and Penicillium fungi, and the common pests during storage, that is, Sitophilus oryzae and Rhyzopertha dominica. Furthermore, this paper pointed out that the quantitative determination of characteristic VOCs, the numeration relationship between VOCs and the degree of mildew and insect infestation, the further expansion of detection range, and the application of degraded rice should be the spotlight of future research.