Starch fraction profiles of milled,nonparboiled rice varieties from Nigeria

This study determined the levels of nutritionally important starch fractions in selected milled, nonparboiled rice cultivated in Nigeria. Five improved varieties (FARO 52, FARO 57, FARO 44, FARO 60 and FARO 61) and four local varieties (Kwandala, Yardass, Jeep and Jamila) were evaluated. There were significant differences in starch fractions among varieties. Resistant starch (RS) ranged between 1.43% and 3.13%. Rapidly digestible starch (RDS) was lowest in Jamila (27.70%) and highest in FARO 61 (39.26%). Generally, the local varieties had significant higher RS (2.71%) with a lower RDS (32.82%) compared with improved varieties (RS; 1.88% and RDS; 36.07%). RS was inversely related to RDS and starch digestion index (SDI). The SDI had a highly significant positive correlation with RDS (r = 0.879, P < 0.01). These results highlight the need for further work in the identification of milled, nonparboiled rice varieties with less rapid digestion for its associated health benefits to consumers.     

Physicochemical properties,anti-nutritional and bioactive constituents,in vitro digestibility,and techno-functional properties of bioprocessed whole wheat flour

This study investigated the impact of bioprocessing techniques (germination, solid-state fermentation, the combination of germination, and solid-state fermentation) on the physicochemical properties, anti-nutritional and bioactive constituents, in vitro digestibility, and techno-functional properties of whole wheat grains were investigated. Bioprocessed whole wheat flour (WWF) samples and the raw flour (control) were prepared using standard procedures. Proximate, anti-nutritional, mineral and amino acid (AA) compositions, protein digestibility, antioxidant activities, starch characteristics, and techno-functional properties were studied using standard methods. The bioprocessing methods increased (p ≤ 0.05) the protein (13.37–16.84 g/100 g), total dietary fiber, mineral constituents, resistant starch (7.19–9.87 g/100 g), slowly digestible starch, phenolic content, antioxidant activities (ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity), most AAs, and protein digestibility. Also observed were decreases (p ≤ 0.05) in rapidly digestible starch, phytic acid, tannin, and trypsin inhibitor activity. The adopted bioprocessing techniques modified the thermal, functional, color, and pasting properties of the WWF and resulted in molecular interactions in some functional groups, as revealed by Fourier transform infrared spectroscopy, compared to the raw flour. The combination of germination and fermentation improved the physicochemical (titratable acidity = 4.93%), protein (16.84/100 g) and starch digestibility (resistant starch = 9.87%), antioxidant (FRAP = 78.90 mg/GAE/100 g), and mineral contents (calcium = 195.28 mg/100 g), modified the pasting (peak viscosity = 90.34 RVU), thermal (peak temperature = 64.82°C), and color properties of WWF with reduced anti-nutritional factors. The combination of these processing techniques could serve as a natural and low-cost technique for the modification of whole wheat functionality and subsequently as an improved functional ingredient during food product development.     

Physical and Pasting Properties of ‘Ofada’ Rice (Oryza sativa L.) Varieties

In this study, grain physical and pasting properties of ofada rice cultivated in South-West Nigeria was evaluated using Standard Evaluation System (SES) for rice with the aim of providing basic information for brand development and utilization of ofada in the development of novel food products. Results showed that size and shape of ofada rice ranged from 5.9 to 9.0 mm and 1.8 to 3.0 mm respectively. The 1000-grain weight was between 24.0 to 31.0 g. Percentage hull was significantly different among the cultivars, ranging from 16 to 21. Peak viscosity ranged between 112.7 and 152.8 BU, minimum, setback and final viscosities varied from 80.3 to 117.2 BU, 104.0 to 143.3BU and 190.8 and 232.3 BU respectively. Gelatinization temperature was not significantly different and varied between 64.1 to 64.7 °C. Significant difference (p < 5%) was observed among the samples in terms of minimum setback and final viscosities respectively. Significant negative association was observed between kernel length and gelatinization temperature (r = – 0.65), setback and gelatinization temperature (r = – 67) while positive correlation was observed between breakdown viscosity and peak viscosity (r = 0.86). The good pasting behaviour makes ofada flour good material for the production of stiff dough products, better palatability and water binding capacity while physical qualities give ofada an advantage during milling. This attributes could be exploited for the development of new varieties and utilization in food development of the ofada rice value-chain.     

On the study of efficiency of exponential-type estimator of population mean using robust regression methods

This study aimed at enhancing the efficiency of Zaman estimators using exponential transformation technique. A new class of estimators was obtained using the concept of Bahl and Tuteja. The bias and mean squared error (MSE) of the new class of suggested estimators was derived up to second degree approximation. The empirical study through simulations was conducted using Normal, exponential, gamma, chi-square and beta distributions under robust regression methods (Huber-M, Huber-MM, LTS (least trimmed squares) and LMS (least median of squares)) and the results revealed that proposed estimators were more efficient.