Review of technology advances to assess rice quality traits and consumer perception

Enhanced leaf photosynthesis, grain yield, rice quality and aroma characteristics in rice grains (Oryza sativa L.) with foliar application of selenium nanoparticles

The potential of selenium nanoparticles application for rice with higher yield and quality, especially in great selenium bioavailability and rich aroma, is a crucial objective. In this study, a two-year field experiment was conducted to investigate the influence of selenium nanoparticles (Se NPs) foliar spraying on the grain yield, rice quality, selenium bioavailability and aroma formation. Our results demonstrated that Se NPs foliar application significantly increased the activities of peroxidase, superoxide dismutase and catalase (POD, SOD and CAT), and decreased the malondialdehyde (MDA) content to increase the SPAD value and net photosynthetic rate in flag leaves at 10-25 days after heading, which finally increased the grain yield by 1.3-3.7 % for improved grain filling, compared to CK. The increased grain filling also contributed to better rice quality, like higher taste value (2.4-6.9 %) and breakdown value (32.2-48.0 %), as well as lower amylose content (5.1-15.9 %), chalkiness grain rate (8.4-49.2 %) and degree (11.5-50.4 %). Meanwhile, Se NPs application improved the selenium bioavailability by increasing the selenium content and proportion in the rice edible parts. The further analysis indicated that the Se NPs application primarily enhanced the proline content and proline oxidase activity from heading to 10 days after heading, improving the initial synthesis of Δ1-pyrroline-5-carboxylic acid (P5C) for the vital 2-acetyl-1-pyrroline (2-AP) production during 10-25 days post-heading, which promoted the remarkable increase of the final 2-AP content (5.0-19.8 %). These findings showed that Se NPs can be practically applied as the foliar fertilizer for quality improvement, selenium bioavailability enhancement and aroma enrichment in rice grains.

Regulation of Rice Grain Quality by Exogenous Kinetin During Grain-Filling Period

Cytokinins (CKs) play important functions in plant growth and development and in response to adversity stress. However, little is known about the role CK plays in rice grain quality. We hypothesized that exogenous cytokinins could improve rice grain quality by regulating physiological traits and genes related to starch synthesis. Therefore, we exogenously applied different concentrations of kinetin (KT), an exogenous CK, during the grain-filling period. Our results show that all the different concentrations of exogenous KT treatments resulted in a significant increase in thousand-grain weight. In particular, chalkiness and chalky grain rate were significantly reduced, and gel consistency (GC) content and alkali spreading value (ASV) were significantly increased in 10-8 M KT treatment. Meanwhile, the exogenous application of 10-8 M KT positively affected the transcription of some starch synthesis-related genes, which was in contrast to the 10-5 M KT treatment. In conclusion, the exogenous application of appropriate concentrations of KT during the grain-filling period can ultimately affect rice grain quality by regulating the changes in the relevant indicators, such as appearance quality (AQ) and eating and cooking qualities (ECQ).

Recent advances in non-invasive techniques for assessing food quality: Applications and innovations

The global concern for ensuring the safety and authenticity of high-quality food necessitates continuous advancements in food assessment technologies. While conventional methods of food assessment are accurate and precise, they are also laborious, destructive, time-consuming, energy-intensive, chemical-demanding, and less eco-friendly. Their reliability diminishes when dealing with large numbers of food samples. This chapter explores recent advances in non-invasive technologies for food quality assessment, including spectroscopy, optical imaging, and e-sensors. Enhanced by artificial intelligence (AI), these technologies have shown remarkable capabilities in rapid and accurate food identification, authentication, physical appraisal, early disease detection, chemical analysis, and biochemical evaluation. As a result, non-invasive technology holds the potential to revolutionize food quality assessment and assure food safety at every stage of the food supply chain.

The Effects of Genotype × Environment on Physicochemical and Sensory Properties and Differences of Volatile Organic Compounds of Three Rice Types (Oryza sativa L.)

Understanding the effects of genotype, environment and their interactions on rice quality is of great importance for rice breeding and cultivation. In this study, six rice varieties with two indica, two japonica and two indica-japonica types of rice were selected and planted at ten locations in Zhejiang Province to investigate the genotype (G) × environment (E) on physicochemical and sensory properties and the differences of volatile organic compounds (VOCs) among the three types of rice. Analysis of variances showed that apparent amylose content (AC), total protein content (PC), alkali spreading value (ASV), RVA profiles, and appearance (ACR), palatability (PCR), and sensory evaluation value (SEV) of cooked rice and texture of cooled cooked rice (TCCR) were mainly affected by genotypic variation, whereas the smell of cooked rice (SCR) was mainly affected by environment (p < 0.05). The G × E effect was significant for most parameters. The weather in the middle and late periods of filling had important effects on the formation of rice quality, especially on setback (SB) and pasting temperature (PT) (p < 0.01). They were negatively correlated with the texture of cooked rice (TCR) and SEV (p < 0.05). Peak viscosity (PV) and breakdown (BD) were positively related to the sensory evaluation parameters (p < 0.01) and could be used to predict cooked rice quality. A total of 59 VOCs were detected, and indica, japonica and indica-japonica had 9, 6 and 19 characteristic compounds, respectively. The principal component analysis showed that the physicochemical and sensory properties and VOCs of indica-japonica rice were more stable than those of indica and japonica rice at ten locations in Zhejiang Province. It is helpful for rice breeders to understand how the environment affects the physicochemical, sensory properties and VOCs of the three rice types, and it is also important for food enterprises to provide rice products with stable quality.