Effect of Endogenous Lipids and Proteins on the Antioxidant, in vitro Starch Digestibility, and Pasting Properties of Sorghum Flour

This study evaluated the effect of endogenous lipids and proteins on the antioxidants, starch digestibility, and pasting properties of sorghum (Sorghum bicolor) flour (SF). Endogenous lipids and/or proteins were removed from different portions of SF to obtain defatted (DF), deproteinized (DP), and defatted and deproteinized (DF-DP) flours. Bioactive constituents (total phenolics, tannins, flavonoids, saponins, and anthocyanins), antioxidant activities [2,2-Azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) radical cation (ABTS*+) and 2, 2-Diphenyl-2-picrylhydrazyl radical (DPPH*) scavenging activities, reducing power, and Fe2+ chelating capacity], starch, amylose, starch hydrolysis index (HI), estimated glycemic index (eGI), and pasting properties of treated and control (untreated) flours were determined. The control flour (SF) had significantly higher (p < 0.05) levels of all the bioactive constituents and antioxidant activity tested than the DF, DP, and DF-DP flours, while the DF-DP flour had the least levels of bioactive constituents and antioxidant activity. In contrast, the starch, amylose, HI, and eGI were consistently in the order of DF-DP > DF > DP > control flour (p < 0.05). The control flour had the highest (p < 0.05) peak viscosity, and the least peak time and pasting temperature, while the DF flour had the highest final viscosity. Therefore, endogenous lipids and proteins contribute to the antioxidant, starch digestibility, and pasting properties of sorghum flour.

Influence of Phosphorylation and Acetylation on Structural, Physicochemical and Functional Properties of Chestnut Starch

Chestnut is popular worldwide for its unique flavor, high eating quality and nutrition. Here, we evaluated the influence of phosphorylation and acetylation on the structural, physicochemical and functional properties of chestnut starch. Scanning electron micrographs showed the agglomeration of starch granules and the appearance of numerous dents on the starch granule surface under phosphorylation and acetylation. X-ray diffractograms confirmed that the modification treatments did not affect the C-type crystal pattern, but reduced the relative crystallinity of the chestnut starch, particularly phosphorylation. Moreover, modification improved the paste transparency of the starch. Differential scanning calorimeter analysis revealed that the gelatinization temperature and enthalpy of the starch decreased with the increasing substitution degree, particularly in phosphorylated starch. The Rapid Visco Analyser analysis demonstrated that phosphorylation could greatly improve the pasting properties of chestnut starch. In addition, phosphorylated and acetylated starch had a smaller amount of slowly digested starch and a larger amount of resistant starch relative to native chestnut starch. In conclusion, the functional and physicochemical properties of chestnut starch can be significantly improved through phosphorylation and acetylation, demonstrating its great application potential as a food additive.

Characteristics of Physicochemical Properties of Chalky Grains of Japonica Rice Generated by High Temperature during Ripening

Global warming has caused devastating damage to starch biosynthesis, which has led to the increase in chalky grains of rice. This study was conducted to characterize the qualities of chalky rice grains and to develop the estimation formulae for their quality damage degree. We evaluated the chalkiness of 40 Japonica rice samples harvested in 2019, in Japan. Seven samples with a high ratio of chalky rice grains were selected and divided into two groups (whole grain and chalky grain). As a results of the various physicochemical measurements, it was shown that the surface layer hardness (H1) of cooked rice grains from chalky grains was significantly lower, and their overall hardness was significantly lower than those from the whole grains. In addition, α- and β-amylase activities, and sugar contents of the chalky rice grains were significantly higher than those of the whole rice grains. The developed estimation formula for the degree of retrogradation of H1 based on the α-amylase activities and pasting properties, showed correlation coefficients of 0.84 and 0.81 in the calibration and validation tests, respectively. This result presents the formula that could be used to estimate and to characterize the cooking properties of the rice samples ripened under high temperature.

Proximate composition, pasting and functional properties of composite flour blends from cassava and chia seeds flour

The study established the proximate composition, pasting, and functional properties of cassava flour (CF) blended with chia seeds flour (CSF). Composite flour was prepared by blending CF with CSF in the ratios of 95:05, 90:10, 85:15, 80:20, and 75:25 with CF and CSF used as controls, respectively. The effect of blending significantly (p < 0.05) increased protein, fat, fibre, and ash contents as CSF increased. On other hand, moisture and carbohydrate contents decreased significantly. Pasting properties of composite flour blends decreased significantly (p < 0.05) as the incorporation of CSF increased and a noticeable change was observed for composite flour (75:25) except for peak time and pasting temperature. Functional properties of water absorption capacity (WAC) of CSF were significantly different with CF and composite flour blends. Oil absorption capacity (OAC) of CF and CSF were significantly different, while the composite flour blends had varied OAC due to the inclusion of the different amounts of CSF. The swelling capacity (SC) of CF and CSF were not significantly different, but composite flour blends were significantly different from both CSF and CF. The least gelation concentration (LGC) and bulk density (BD) increased significantly as chia seeds increased. Increased concentration of chia CSF in the composite flour blends showed to alter the functional properties. This study recommends composite flour 75:25 for processing semiliquid products like porridge due to reduced pasting properties values that may be associated with increased energy density compared to CF.

Physicochemical, structural, and rheological characteristics of corn starch after thermal-ultrasound processing

Thermal-ultrasound treatment is a green technology that can significantly alter the structural and functional properties of starches. This research extend the effect of at different temperatures (25 °C, 45 °C, and 65 °C) and times (30 and 60 min) on the physicochemical, structural, and rheological properties of corn starch was studied. Amylose content, solubility, swelling power, and the least gelling content increased with increasing temperature and time. Starch treated at 45 °C for 30 min had the lowest syneresis among all treatments. Thermal-ultrasound treatment at 25 °C and 65 °C for 60 min caused increasing paste clarity. Microscopic observations demonstrated that the starch granules were agglomerated at 65 °C. Although the crystallinity of samples decreased from 35.42% to 8.94%, the storage modulus was more than the loss modulus during the frequency sweep test. Pasting properties showed that pasting temperatures shifted to higher values after treatment. Nonetheless, the maximum viscosity decreased, and the final viscosity of the treated samples demonstrated that short-term retrogradation could deteriorate. Results showed that thermal-ultrasound is a viable technique for starch modification compared to conventional thermal and ultrasound treatments.

Physicochemical, Functional and Pasting Properties of Garri Fortified with Soybean Flour

Aim: This study evaluated the physicochemical, functional and pasting properties of garri fortified with soybean flour. Methodology: Soybean flour was incorporated into the garri prior to garrification at a ratio of 10, 20, 30, 40 and 50% for samples A, B, C, D and E respectively. Sample without soybean flour served as control. Standard analytical procedure was used in the evaluation of all six samples. Results: The pH and titratable acidity (TTA) of the samples varied respectively, from 4.59 - 6.48 and 0.08 - 0.17 % lactic acid. There was significant (P<0.05) decrease in pH with increase in soybean flour, while the reverse was the case for TTA. Swelling power, bulk density and water absorption capacity of the soybean fortified garri ranged from 8.74 - 17.81%, 0.60 - 0.80 g/ml and 13.44 – 19.43 % respectively. Control sample (100% garri) had hydrogen cyanide (HCN) content of 1.50 mg HCN/100g while samples with soybean flour had no detectable levels. Peak viscosity, trough, breakdown, final viscosity and setback varied significantly (P<0.05) from 101.19 - 399.44, 90.92 - 320.19, 10.28 - 79.25, 123.19 - 451.50 and 32.28 - 131.31 RVU respectively. Peak time and pasting temperatures ranged from 5.18 – 6.34 min and 74.28 – 92.88 oC. Conclusion: The study revealed that a good quality garri can be produced with the incorporation of soybean flour up to 50%, the garri is safe for consumption as there was no HCN detected, and the decrease in viscosity provides for a soft textured, mouldable garri that is convenient for swallow.

Comparative Analysis Reveals Changes in Some Seed Properties in Amaranth Mutant Variety ‘Zobor’ (A. hypochondriacus × A. hybridus)

The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe.

Effect of Zn-Rich Wheat Bran With Different Particle Sizes on the Quality of Steamed Bread

Bran is the main by-product of wheat milling and the part of the grain with the highest Zn content. We investigated the effects of the particle sizes (coarse, D50 = 375.4 ± 12.3 μm; medium, D50 = 122.3 ± 7.1 μm; and fine, D50 = 60.5 ± 4.2 μm) and addition level (5–20%) of Zn-biofortified bran on the quality of flour and Chinese steamed bread. It was studied to determine if the Zn content of steamed bread could be enhanced without deleterious effects on quality. Dough pasting properties, such as peak viscosity, trough viscosity, final viscosity, breakdown, and setback, decreased significantly as the bran addition level was increased from 5 to 20% but did not significantly differ as a result of different bran particle sizes. Bran incorporation significantly increased hardness, gumminess, chewiness, and adhesiveness, whereas the springiness, cohesiveness, and specific volume of steamed bread decreased with the increase in bran addition. The optimal sensory score of steamed bread samples in the control and Zn fertilizer groups were obtained under 5% bran addition resulting in comparable flavor, and texture relative to control. Meanwhile, the Zn content of the steamed bread in the Zn fertilizer group was 40.2 mg/kg, which was 55.8% higher than that in the control group. Results indicated that adding the appropriate particle size and amount of bran would be an effective and practical way to solve the problem of the insufficient Zn content of steamed bread.

Effects of Fermented Maize Residue Addition on the Physico-chemical and Sensory Properties of Chin-Chin

Chin-Chin, a traditional Nigerian snack was prepared utilizing wheat-fermented maize residue composite flour at 0 – 30% replacement levels. Effects of this addition on the functional and pasting properties of the flour composite was evaluated. The snack produced was also evaluated for its sensory attributes, proximate composition and invitro-protein digestibility (IVPD). Functional properties results showed an increase in water absorption capacity (WAC), a decrease in oil absorption capacity (OAC), decrease in Bulk Density (BD), swelling power and solubility index with residue addition. Pasting property results showed a drop in the value of peak, trough, breakdown and final viscosity with substitution while set back viscosity increased.Peak temperature decreased, but values for pasting temperature showed no significant difference between the control and the blends. Results for sensory evaluation showed equal preference for overall acceptability. Proximate composition results showed residue addition led to an increase in crude fibre and protein content with a drop in the carbohydrate value. Residue addition did not increase protein digestibility. Addition of fermented maize residue in chin-chin production can be another way of utilizing the fibre rich by-product of the production of fermented maize starch.