Search Results (38)

Vibrational spectroscopy, including Raman and near-infrared techniques, enables the non-destructive evaluation of starch gelatinization, head rice yield, and aroma-active volatile compounds in parboiled rice subjected to varying soaking and drying conditions. Raman and NIR spectra were collected for rice samples processed under different conditions and integrated with reference analyses to develop and validate partial least squares regression and artificial neural network models. The optimized PLSR model demonstrated strong predictive performance, with R² values of 0.9406 and 0.9365 for SG and HRY, respectively, and residual predictive deviations of 3.98 and 3.75 using Raman effective wavelengths. ANN models reached R² values of 0.97 for both SG and HRY, with RPDs exceeding 4.2 using NIR effective wavelengths. In the aroma compound analysis, p-Cymene exhibited the highest predictive accuracy, with R² values of 0.9916 for calibration, and 0.9814 for cross-validation. Other volatiles, such as 1-Octen-3-ol, nonanal, benzaldehyde, and limonene, demonstrated high predictive reliability (R² ≥ 0.93; RPD > 3.0). Conversely, farnesene, menthol, and menthone showed poor predictability (R² < 0.15; RPD < 0.4). Principal component analysis revealed that the first principal component explained 90% of the total variance in the Raman dataset and 71% in the NIR dataset. Hotelling’s T² analysis identifies influential outliers and enhances model robustness. Optimal processing conditions for achieving maximum HRY and SG values were determined at 65 °C soaking for 180 min, followed by drying at 70 °C. This study underscores the potential of integrating vibrational spectroscopy with machine learning techniques and targeted wavelength selection for the high-throughput, accurate, and scalable quality evaluation of parboiled rice. Full article

Rich in bioactive compounds, pigmented rice offers superior antioxidant capacity compared to non-pigmented rice. Processing methods like milling, parboiling, thermal treatments (e.g., extrusion cooking), and biobased approaches (e.g., germination and fermentation) impact the technological and nutritional properties of pigmented rice. All products with added pigmented rice showed improved total phenolic content and antioxidant capacities. Extrusion cooking improved technological properties of dough, bread, and bakery products by modifying the pasting properties of rice. Germination and fermentation enhanced bakery products’ nutritional value by increasing gamma-aminobutyric acid (GABA) levels. Pigmented rice flour can enhance the volume, crumb firmness, and elasticity of gluten-free (GF) bread, especially with ohmic heating. It improved sensory qualities and consumer acceptance of various baked products and extruded snacks. While pigmented rice-based pasta and noodles had compromised cooking qualities, germination improved noodle cooking qualities. Pre-processing techniques like parboiling and micronisation show potential for improving pigmented rice’s technological properties and warrant further study. In conclusion, pigmented rice can enhance the technological and nutritional qualities of bread, bakery products, and snacks. Future researches should focus on agronomic advancement, optimization of pre-processing and processing techniques, exploring varietal differences among pigmented rice cultivars, and promotion of consumer awareness and market potentials. Full article

Type 2 diabetes mellitus (T2DM) represents a significant global health burden, especially in populations where rice constitutes a dietary staple. Parboiled rice (PBR), known for its lower glycemic index compared to conventional white rice (WR), may offer benefits in managing postprandial hyperglycemia. Nevertheless, the impact of PBR consumption on insulin sensitivity, β-cell function, and incretin hormone responses remains poorly understood. Methods: This randomized crossover pilot study aimed to assess and compare the acute effects of PBR and WR intake on postprandial glucose regulation, insulin sensitivity, β-cell functionality, and glucagon-like peptide-1 (GLP-1) responses in healthy subjects and individuals with T2DM. A total of 20 participants were recruited and evenly allocated into healthy (n = 10) and T2DM (n = 10) groups. Following the ingestion of either PBR or WR, blood samples were collected at fasting and various postprandial intervals to determine glucose, insulin, and GLP-1 levels. Insulin sensitivity and β-cell function were evaluated using HOMA-IR, Matsuda Index (MI), and Disposition Index (DI). Results: As expected, T2DM participants exhibited significantly elevated fasting glucose and insulin levels compared to healthy controls. Consumption of PBR led to significantly lower postprandial glucose responses in healthy subjects relative to WR. Although a similar trend of reduced glucose levels was observed in T2DM subjects after PBR intake, this reduction did not reach statistical significance. Parallel trends were observed in insulin secretion patterns. Moreover, GLP-1 responses were notably diminished in T2DM individuals compared to healthy participants. Importantly, MI and DI values significantly increased after PBR consumption in healthy individuals compared to those with T2DM, indicating improved insulin sensitivity and β-cell responsiveness. Conclusions: These preliminary findings suggest that PBR consumption may confer beneficial effects by lowering postprandial glucose and enhancing insulin sensitivity. Further studies with larger cohorts are warranted to confirm these outcomes and elucidate the physiological mechanisms behind PBR’s potential role in dietary management strategies for T2DM. Full article

Rice milling in Sub-Saharan Africa (SSA) remains highly dependent on water availability and favorable weather conditions, making local millers vulnerable to water- and weather-related pressures (WWrP). This study examines how rice millers in Makurdi and Adikpo, Benue State, Nigeria, adapt to these pressures. Data were collected through snowball sampling involving 21 rice millers and two workshops attended by 14 millers. Content and thematic analyses of data were carried out using NVivo 11. Findings indicate that rice milling operations are highly exposed and sensitive to flooding, excessive wetness, dryness, high humidity, and water scarcity. These pressures are likely to intensify due to climate change and pronounced climate variability. To adapt, millers employ endogenous strategies, including temporarily relocating or evacuating mills, rotating drying schedules, modifying drying methods, reducing or suspending parboiling during floods, and digging wells. In spite of these adaptation measures, locally milled rice continues to face issues of poor quality and diminished competitiveness. Consequently, this study highlights upgrading milling technologies and infrastructure, promoting proactive and long-term adaptation measures, and supporting collective adaptation strategies among millers to enhance resilience in the rice value chain. Full article

Rice is a staple food in Côte d’Ivoire, but parboiling remains a weak link in the local rice value chain. Parboiled rice has superior nutritional and physical properties compared with white rice. In 2017, AfricaRice introduced the “Grain quality enhancer, Energy efficient, and durable Material” (GEM) parboiling system in Côte d’Ivoire to address these challenges. This study evaluated the rice value chain, parboilers’ perceptions of GEM technology, and its role in upgrading the rice value chain. Using two survey types (parboiler association level (focus group) and parboiler household level), 179 rice parboilers and 77 key players were randomly sampled and interviewed in Côte d’Ivoire. We used descriptive statistics and the parboiler budget for the profitability analysis. The results show that parboiling, primarily undertaken by women, is profitable in Côte d’Ivoire. Parboilers identified the key advantages of the GEM system, including improved rice quality, higher output rates, better nutritional value, and the ability to parboil larger volumes of rice. GEM technology enhanced rice quality, increased parboilers’ incomes, and reduced energy costs by 22.3%, saving an average of 73,090 FCFA per ton of parboiled paddy. The study recommends scaling up GEM technology through local fabricator training and broader dissemination in rice-growing regions to further strengthen the rice value chain in Côte d’Ivoire. Full article

Xanthan is a highly relevant commercial microbial biopolymer. Its production occurs in two steps: the bacterium is cultivated in a nitrogen-rich medium for cell multiplication, and the obtained biomass is used as an inoculum for the polymer production phase. Different media compositions for cell growth were investigated, seeking to reduce or replace the peptone used in the standard medium. Peptone (P), yeast extract (YE), and rice parboiling water (RPW) concentration combinations were tested in cultivating Xanthomonas arboricola pv. pruni 101. A CRD 2³ design, performed in a shaker, was used to assess the effects of independent variables on xanthan pruni microbial growth, N consumption, yield, viscosity, pseudoplasticity, and xanthan mineral content. After 24 h an increase in N was observed, without any significant impact on cell growth. Xanthan yield increased as a result of the alternative treatments, with P and YE influencing positively. However, T1, with the lowest levels of P, YE, and RPW increased viscosity and pseudoplasticity of xanthan pruni. RPW increased phosphorus, silicon, calcium, and magnesium, and P and YE increased potassium. These results indicate that partial replacement of P by RPW and YE is an economically viable and sustainable approach for the xanthan pruni production. Full article

Endophytic fungi are valuable sources of bioactive secondary metabolites, with potential applications in pharmaceutical and agricultural fields. This study investigates the metabolic potential of Diaporthe hongkongensis, an endophytic fungus isolated from Minquartia guianensis. To date, no secondary metabolites have been identified from this species, highlighting the novelty of this research and its contribution to understanding the chemical diversity of endophytic fungi. The fungus was cultivated on parboiled rice under static and dark conditions for 28 days, leading to the isolation of the following three compounds: 5,6-dihydro-5,6-epoxymultiplolide A (1), cytosporone C (2), and uridine (3). Structural identification was carried out using nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. The results revealed the metabolic versatility of D. hongkongensis, as demonstrated by its ability to produce structurally diverse substances with biological relevance. Hence, it describes the first isolation of secondary metabolites from the endophytic fungus D. hongkongensis, marking a significant step in understanding its chemical profile. The identification of a known antifungal compound and a lactone derivative underscores the biosynthetic potential of this endophytic fungus, while the isolation of a nucleoside expands the chemical repertoire of fungal metabolites, suggesting possible roles in cellular metabolism and stress adaptation. These findings highlight the role of endophytic fungi as prolific sources of structurally diverse and potentially bioactive natural products, supporting further exploration of their biotechnological applications. Full article

Effective blood glucose management is essential for individuals with type 1 diabetes, particularly when dietary adjustments involve staple foods like rice. As a primary carbohydrate worldwide, rice significantly influences the glycemic index (GI) based on its type and cooking method. This study investigated the impact of rice type and boiling duration on the GI in healthy adults using an in vivo approach aligned with ISO 2010 standards. The glycemic response to four rice types (white round-grain, parboiled medium-grain, white long-grain, and whole-grain long-grain) was measured through postprandial blood glucose levels under both standard and extended boiling conditions to assess their implications for dietary glycemic control. Ten healthy participants (mean age 25 years, body mass index (BMI) 23.0 ± 1.6 kg/m²) consumed rice samples containing 50 g of available carbohydrates, prepared under controlled boiling conditions. Postprandial glycemic response was measured at regular intervals over 2 h following ingestion, with glucose solution as a reference food. The GI was calculated based on the incremental area under the glycemic response curve for each rice sample. Extended boiling significantly increased the GI across all rice types. White round-grain rice exhibited the highest relative increase (+15.8%) in the GI, while whole-grain long-grain rice, despite showing a greater percentage increase (+25.4%), maintained the lowest overall GI due to its high amylose and fiber content. Rice types with higher amylopectin content demonstrated faster glycemic responses and higher GI compared to high-amylose types. This study highlights rice type and cooking time as critical factors influencing postprandial glycemic response. Shorter boiling durations may benefit individuals requiring strict glycemic control, particularly those with diabetes, underscoring the importance of personalized dietary guidance for managing glycemic outcomes effectively. Full article

One of the major challenges for crop breeding scientists is climate change. Their task is to develop new crop varieties that can withstand this phenomenon. For this study, a new Egyptian paddy variety called Giza 183, which is designed to adapt to mitigate the effects of climate change, was chosen. We focused on examining the physical and engineering properties of this variety in order to design strategies for storage, handling, transportation, drying, parboiling, and processing equipment in rice mills. The goal was to minimize post-harvest losses during the milling process, thereby maximizing high-quality yields while reducing losses. The physical properties of the rice grains, such as the length, width, and thickness, were measured at an average moisture content of 13.7% ± 0.25% (wet basis). The results reveal that the mean values of length, width, and thickness averaged 7.50 mm, 3.18 mm, and 2.19 mm, respectively. Additionally, the geometric mean diameter, the equivalent mean diameter, surface area, arithmetic mean diameter, and volume were approximately 3.74 mm, 2.38 mm, 37.37 mm², 4.29 mm, and 28.23 mm³, respectively. The mean of sphericity was 49.9%, and the grain shape (length/width) was 2.19. The true density was measured at 1218.28 kgm⁻³, while the bulk density was 572.17 kgm⁻³. The porosity was found to be 53.03%. Furthermore, the milling production rates for brown rice, hull, white rice, and broken rice were determined to be 76.83%, 23.15%, 67.97%, and 17.36%, respectively. The average weight of one thousand grains was 25.49 g. A linear regression model for describing the mass of rough rice grain was investigated. The mass was estimated with the single variable of the grain aspect ratio (width/length) with a determination coefficient of 0.9908. Information gained from the current study will be useful in designing post-harvest processing and storage structures in rice processing industries. Full article

Parboiling influences chemical compositions in rice grains. The objectives of this study were to evaluate the change in chemical content, total phenolic content and antioxidant capacity of landrace rice genotypes under parboiling conditions and to identify the genotypes suitable for production of parboiled rice. Landrace rice varieties used in this study consisted of Glam Feang, Glam Tonkeaw, Kawgum, Glam Luem Phua, Medmakham, Deang Sakonnakhon, Sang Yod, Kawniewd-eang, Mali Deang, KDML105 and RD6. Parboiling reduced fiber content, total phenolic content and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity in rice grains. Fiber contents were 1.46% in brown rice (unpolished rice) and 1.40% in parboiled rice (24 h of soaking and 48 h of incubation). Total phenolic contents were 205.67 mg/100 g seed in brown rice and 35.34 mg/100 g seed in parboiled rice. Antioxidant capacity (DPPH) reduced from 68.45% in brown rice to 26.23% in parboiled rice. Ash content and protein content were not significantly affected by the parboiling process. Medmakham cv. had the highest total phenolic content and antioxidant capacity in brown rice and parboiled rice. Gum Leamphea cv. and Medmakham cv. were the best genotypes for ash content, protein content, total phenolic content and antioxidant capacity (DPPH) in brown rice and parboiled rice. Glam Feang cv. had the highest protein contents in brown rice and parboiled rice although it had low total phenolic content and antioxidant capacity. Cluster analysis further showed variation among genotypes, revealing distinct groupings in brown rice and parboiled rice based on chemical properties, phenolic content and antioxidant capacity. This research significantly contributes to a better understanding on how parboiling affects rice compositions and nutritional values. It emphasizes the importance of nuanced comprehension of how different rice varieties respond to parboiling, aiding informed decisions in rice processing and selection to meet specific nutritional needs. Full article

Rice (Oryza sativa L.) is the principal staple food, a fundamental component of food security, a significant source of energy and major nutrients, and a key player in the overall nutritional status in Bangladesh. Parboiling is a common rice-processing treatment in Bangladesh. Recently, polishing has also become a common practice among millers seeking to attract consumers. Polishing may influence the nutrient composition of rice. The present study aimed to investigate the impact of parboiling and polishing on the nutritional content of the five High Yield Varieties (HYVs) of rice (BR11, BRRI dhan28, BRRI dhan29, BRRI dhan49, and BRRI dhan84) and their percent contributions to the Recommended Dietary Allowances (RDA) of vitamins and minerals. All of the rice samples were analyzed for proximate parameters, vitamins (B1, B2, B3, B6, and folate), and minerals (Ca, Mg, Fe, Zn, Na, K, P). Moisture, ash, fat, and total dietary fiber (TDF) were determined gravimetrically, according to the AOAC Official Methods; protein was measured by the Kjeldahl method; B-group vitamins were measured using Ultra Pressure Liquid Chromatography; and mineral content was determined by ICP-OES. The energy, protein, fat, and total dietary fiber (TDF) content of the samples ranged between 342–357 kcal/100 g, 6.79–10.74 g/100 g, 0.31–1.69 g/100 g, and 2.59–3.92 g/100 g respectively. Thiamin, riboflavin, niacin, pyridoxin, and folate content ranged from 0.11–0.25 mg/100 g, 0.01–0.05 mg/100 g, 2.82–6.42 mg/100 g, 0.12–0.30 g/100 g, and 5.40–23.95 g/100 g respectively. In a comparison of parboiling and polishing, macronutrients and vitamin retention were higher in parboiled unpolished rice than in polished unparboiled rice. The minerals (mg/100 g) Ca, Mg, Fe, Zn, Na, K, and P were in the ranges 32.82–44.72, 30.69–58.34, 0.51–0.70,1.83–2.79, 5.00–5.36, 106.49–112.73, and 162.23–298.03. Minerals of BRRI dhan84 were unaffected by polishing and parboiling. BRRI dhan84 contributed a higher percentage of RDA of all B vitamins and minerals. Therefore, to reduce nutrient loss in rice, industries and consumers should be encouraged to avoid polishing or limit polishing to 10% DOM and to consume unpolished rice, either parboiled or unparboiled. Full article

Parboiled rice is recognized for its greater milling yield and reduced rice breakage compared to raw rice during processing. Additionally, parboiled rice has better glycemic control and numerous health benefits. However, the production of parboiled rice requires energy-intensive processing as well as wastewater production. This study reviews parboiled rice, including its processing condition, nutritional properties, potential use, emerging green technologies, and health benefits. It also discussed the outlook and challenges regarding parboiled rice. In addition, a novel overview of emerging green solutions applied to the process to minimize wastewater creation during parboiling and reduce excessive energy usage is provided. The limitation of parboiled rice for a new market preference is the color. An intense process would cause an unwanted physical appearance. A thorough study should balance the multiple advantages of parboiled rice with the reasonable intensity of the process. Due to its multiple advantages, parboiled rice is demonstrated to be a possible breakthrough in the agriculture and food industries. This review aims to provide a thorough understanding that can be used for academic and industrial purposes. Full article

Hydrothermal treatment of rice, called “Parboiling”, is an ancient traditional process in Asian countries. It consists of soaking rough rice in water and steaming it, and it both reduces the level of grain breakage and increases head yield of rice during milling. However, parboiling of rice is associated with some drawbacks regarding consumer preferences: the loss of its aroma, reduced rice-kernel whiteness and increased kernel hardness. This research study was carried out to develop a mild hydrothermal treatment that could be applied to basmati paddy by controlling hydrothermal treatment, i.e., soaking water temperature, steaming pressure and time. The Basmati 370 paddy variety was used for this study. The results revealed that, by soaking the paddy in hot water (70 ± 2 °C) for 75 min and steaming the soaked paddy for 20 min with non-pressurized steam at atmospheric pressure, and soaking the paddy for 120 min in hot water (70 ± 2 °C) and steaming the soaked paddy for 4 min with pressurized steam (4 kg/cm²), the optimum treatments are achieved. These optimum hydrothermal treatments were able to produce high head rice yield and preserve the basmati aroma, colour, hardness and palatability characteristics similar to non-parboiled basmati rice. Further, nutritional values such as vitamin B and protein content were also significantly preserved by these mild hydrothermal treatments. These optimized treatment combinations achieved minimized grain breakage while increasing head rice yield during milling and, at the same time, preserved basmati aroma, kernel whiteness, cooking and palatability characteristics similar to non-parboiled rice. Full article

The present study aimed to optimize the recovery of bound phenolic antioxidants from rice hulls via microwave-assisted alkaline hydrolysis using response surface methodology. The microwave treatment duration, temperature, and solvent:solid ratio were the independent variables selected; whereas total phenol content, antioxidant activity (DPPH^●, ABTS^●+, CUPRAC assays), and the p-coumaric and ferulic acids concentration were the dependent ones. The optimum conditions were found to be 3.6 min, 155 °C, and 50:1 v/w which were then applied to hulls from different rice varieties cultivated in Greece [Gladio, Krezo, Scirocco, Karolina (two samples), Europa, Bravo, Bella (parboiled), and Fino (long-grain rice)]. The results were compared to those obtained using an optimized ultrasound-assisted alkaline hydrolysis protocol (120 min, 80 °C, 50:1 v/w) proposed in the literature. The values obtained with microwaves were much higher compared to those obtained by ultrasounds (i.e., p-coumaric acid levels were 1.2 to 2.2-fold higher, and those of ferulic acid were 2.1 to 6.0-fold higher) using almost 2-fold higher temperature but reducing the hydrolysis duration by ~33-fold. Thus, the optimized approach may assist the valorization of rice hulls as a sustainable source of natural phenolic antioxidants for novel food applications. Full article

Hypertension leads to oxidative stress, inflammation, and fibrosis. The suppression of these indicators may be one treatment approach. Parboiled germinated brown rice (PGBR), obtained by steaming germinated Jasmine rice, reduces oxidative stress and inflammation in vivo. PGBR contains more bioactive compounds than brown rice (BR) and white rice (WR). Anti-hypertensive benefits of PGBR have been predicted, but research is lacking. The anti-hypertensive effects of PGBR were investigated in the downstream gene network of hypertension pathogenesis, including the renin–angiotensin system, fibrosis, oxidative stress production, and antioxidant enzymes in N-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats. To strengthen our findings, the cardiac structure was also studied. PGBR-exposed rats showed significant reductions in systolic blood pressure (SBP) compared to the hypertensive group. WR did not reduce SBP because of the loss of bioactive compounds during intensive milling. PGBR also reduced the expression of the angiotensin type 1 receptor (AT1R), transforming growth factor-β (TGF-β), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX4), which contribute to the renin–angiotensin system, fibrosis, and oxidative stress production, respectively. Losartan (Los, an anti-hypertensive drug)-treated rats also exhibited similar gene expression, implying that PGBR may reduce hypertension using the same downstream target as Los. Our data also indicated that PGBR reduced cardiac lesions, such as the cardiomyopathy induced by L-NAME. This is the first report on the anti-hypertensive effects of PGBR in vivo by the suppression of the renin response, fibrosis, and improved cardiac structure. Full article