Breakdown Viscosity Research Articles

Comparison of Structure and Physicochemical Properties of Starches from Hybrid Foxtail Millets and Their Parental Lines

The structure and physicochemical properties of starch were important factors to determine the quality of foxtail millet. While hybrid foxtail millet has made greater progress in yield, it has made slower progress in quality than conventional foxtail millet with a more complex genetic base, which was jointly influenced by the parents. However, there were no reports on the comparison of the starch structure and physicochemical properties of hybrid foxtail millets and their parents. In this study, the amylose content, morphology structure, granule size distribution, X-ray diffraction, short-range ordered structure, pasting properties, and thermal characteristics of starches derived from Changzagu 466 (466), Changzagu 333 (333), Changzagu 2922 (2922) and their parent materials were analyzed. The results showed that compared with male parents, the starches from three hybrid foxtail millets and their female parents had larger average particle size, d(0.1), d(0.5), and gelatinization enthalpy (ΔH), while the amylose content values of three hybrid foxtail millets were 26.0%, 28.8%, and 28.9%, which were between the parents (25.8~27.1%, 25.4~28.8%, and 23.6~29.5%), with conclusion temperature (Tc) being higher than the parents and having a lower breakdown viscosity. The peak viscosity of Changzagu 466 (466) and Changzagu 2922 (2922) was 5235.5 cP and 5190.8 cP, respectively, lower than that of their parents (5321.0~6006.0 cP and 5257.0~5580.7 cP), while the peak viscosity of Changzagu 333 (333) was 5473.8 cP, falling between the parental values (5337.5~5639.5 cP). The cluster analysis results showed that the starch structure and physicochemical properties of hybrid foxtail millet were significantly different from those of female parents, which were mainly influenced by male parents. The findings of this study will establish a theoretical foundation for the enhancement and innovation of high-quality foxtail millet germplasm resources, as well as the development of high-quality hybrid foxtail millet combinations.

Variability of amylose content and its correlation with the paste properties of cassava starch.

The amylose content can significantly impact the diverse industrial applications of cassava starch. This study aimed to assess the variability of cassava germplasm concerning amylose content and other attributes pertinent to root quality, alongside its correlation with paste properties. Starch extracted from 281 genotypes, obtained in germplasm evaluation trials, was evaluated for amylose content, with additional analysis of parameters such as pasting temperature, time to peak viscosity (TPV), viscosity breakdown (BrD), retrogradation tendency, and maximum, minimum, and final viscosities. The genotypes exhibited considerable variation in dry matter content (ranging from 27.06% to 41.02%), starch content (from 14.61% to 25.67%), cyanogenic compounds (1.77 to 7.81), and amylose content (0.05% to 33.23%). High phenotypic variability in paste properties was observed, alongside a low residual effect for most traits, resulting in high broad-sense heritabilities (>0.95). Strong correlations of significant magnitude (>0.80) were found between parameters such as peak viscosity × viscosity breakdown, minimum viscosity × final viscosity, and final viscosity × retrogradation tendency. Moderate correlations were also identified, such as between dry matter content × starch content (0.56). While positive, correlations between amylose content and paste properties were of low magnitude (ranging from 0.13 to 0.35), except for TPV and BrD. Principal component discriminant analysis clustered the germplasm into six distinct groups based on root quality and paste properties, with most improved genotypes falling into two clusters characterized by high starch and dry matter contents. This study underscores the necessity of simultaneous evaluation of amylose content and paste properties in the breeding pipeline. Additionally, clustering cassava genotypes proves beneficial in identifying those that fulfill specific requirements in industrial and breeding applications.

Jicama (Pachyrhizus spp.), a nonconventional starch: Effects of citric acid and heat−moisture treatment on properties of starch and its application in film

AbstractBackground and ObjectivesThis study investigated the effects of citric acid (CA) and heat–moisture treatment (HMT) on the properties of jicama starch (JS). Furthermore, it explores the potential of modified jicama starch for film preparation.FindingsThe amylose content of the JS increases after HMT and decreases for CA‐modified starch. CA and HMT modification lowered the swelling power, solubility, peak viscosity, breakdown viscosity, final viscosity, setback viscosity, and crystallinity percentage compared to the native JS. After modification, there was an increase in the transition and pasting temperature of JS. The strong peak for the control and treated JS was observed at around 1008 cm−1 wavenumber in the Fourier transform infrared spectroscopy. SEM showed the overlapping and clusters of the granules in all the modified JS. Modified JS‐based film significantly affects the water solubility, barrier, and mechanical properties of film. The film's SEM showed that the CA‐ and HMT‐modified films had more homogeneous surfaces than the native JS film.ConclusionsHMT and CA modification significantly impacted JS properties and improved the film properties for further application.Significance and NoveltyThis study's findings will facilitate selecting an appropriate treatment to enhance the properties of JS for applications in food formulation and sustainable packaging.

Pasting, structural properties, and in vitro digestibility of water chestnut (Eleocharis dulcis Burm. f., Cyperaceae) starch co-gelatinized with different hydrocolloids

Hydrocolloids have been widely used to modulate the processing properties of native starch, this study aimed to investigate the effects of carrageenan (KC), tamarind seed polysaccharide (TSP), and xanthan gum (XG) on the pasting, rheology, structural properties, and in vitro digestibility of water chestnut starch (WCS). The pasting results showed that XG increased the peak viscosity (PV), trough viscosity (TV), final viscosity (FV) and breakdown viscosity (BD) of WCS gel, but decreased the setback (SB), TSP significantly increased SB. The rheological data found that KC, TSP and XG increased the apparent viscosity and storage modulus (G') and loss modulus (G'') of WCS, which gradually increased by the concentration gradient of hydrocolloids. The hardness of starch with KC increased from 171.52g to 323.36g, and the addition of 0.3% KC and 0.5% KC enhanced the thermal stability. Furthermore, XG significantly increased the resistant starch (RS) content and decreased the hydrolysis rate of starch. These results will provide theoretical references for expanding the application range of WCS.

Effect of the Autoclaving-Cooling Cycle on the Chemical, Morphological, Color, and Pasting Properties of Foxtail Millet Starch.

This study investigated the effect of the autoclaving-cooling (AC) cycle and the starch-to-water ratio on the chemical, morphological, color, and pasting properties of foxtail millet starch to improve its utilization in the food industry. Starch suspensions were prepared using different starch-to-water ratios (i.e., 1:1 and 1:4), with one to three AC cycles for each ratio. Subsequently, the chemical, morphological, color, and pasting properties of native and autoclaved-cooled foxtail millet starch (ACFS) were determined. The results showed that ACFS had higher overall resistant starch (RS) content than native starch. AC treatment reduced the lightness and whiteness index, gelatinization time, and pasting temperature while increasing particle sizes with irregular shapes and surfaces. Starch treated with distilled water at a 1:1 ratio with two AC cycles (1:1-2C) exhibited the highest amylose, starch, and RS contents with stable pasting properties compared with that in other AC treatments. Pasting stability was indicated by the low breakdown viscosity and high trough and final viscosity. The findings suggest that ACFS treated with 1:1-2C could be a stabilizer and functional food.

Effects of Sulfur Application on the Quality of Fresh Waxy Maize.

Balanced fertilizer application is crucial for achieving high-yield, high-quality, and efficient maize cultivation. Sulfur (S), considered a secondary nutrient, ranks as the fourth most essential plant nutrient after nitrogen (N), phosphorus (P), and potassium (K). S deficiency could significantly influence maize growth and development. Field experiments were conducted in Jiangsu, Yangzhou, China, from April 1 to July 20 in 2023. Jingkenuo2000 (JKN2000) and Suyunuo5 (SYN5) were used as experiment materials, and four treatments were set: no fertilizer application (F0), S fertilizer application (F1), conventional fertilization method (F2), and conventional fertilization method with additional S application (F3). The objective was to investigate the impact of S application on grain weight and the quality of fresh waxy maize flour and starch. The results indicated that all fertilization treatments significantly increased grain weight and the starch and protein contents in grains compared to no fertilization. Among these, F3 exhibited the most significant increases. Specifically, in JKN2000, the grain weight, starch content (SC), and protein content (PC) increased by 27.7%, 4.8%, and 14.8%, respectively, while in SYN5, these parameters increased by 26.3%, 6.2%, and 7.4%, respectively, followed by F2 and F1. Compared to F0, F3 increased starch and protein contents by 4.8% and 14.8% in JKN2000, and by 6.2% and 7.4% in SYN5. Compared to F0, F2 and F3 significantly increased the iodine binding capacity (IBC) of SYN5, with F3 being more effective than F2, while they had no significant effect on the IBC of JKN2000. The peak viscosity (PV) and breakdown viscosity (BD) of waxy maize flour and starch for both varieties showed a consistent response (increasing trend) to S application, and F3 had the largest increase. Regarding the thermal properties of waxy maize flour, F3 significantly enhanced the retrogradation enthalpy (ΔHgel) of both varieties compared to F0, while achieving the lowest retrogradation percentage (%R). In starch, the highest ΔHgel and the lowest %R were observed under the F2 treatment. In summary, under the conditions of this experiment, adding S fertilizer to conventional fertilization not only increased the grain weight of waxy maize but also effectively optimized the pasting and thermal properties of waxy maize flour and starch.

Effects of synergistic action of courgette polysaccharide and coumalic acid on pasting, rheological, and thermal properties of potato starch

AbstractThe effects of courgette polysaccharides (CP) and coumalic acid (COA) on gelatinization, rheology, thermodynamics, microstructure, freeze–thaw stability, and in vitro digestibility of potato starch (PS) were studied. The synergistic effect of CP and COA on PS was further analyzed. The results showed that peak viscosity (PV) decreased from 6649.00 to 3462.50 mPa s and 3825.00 mPa s, respectively, after CP and COA were added. Under the combined effect of the two, it will be as low as 3225.50 mPa s. Besides, trough viscosity (TV), breakdown viscosity (BV), and final viscosity (FV) had the same trend. The presence of CP and COA can significantly delay the short‐term retrogradation of PS, especially in the case of high dose of CP and low dose of COA. Rheological tests showed that all sample gels belonged to the weak gel system (tan δ < 1) and pseudoplastic fluids. Meanwhile, the results of thermodynamic, Fourier transform infrared, and Raman spectroscopy exhibited that the presence of CP and COA significantly retarded the retrogradation of PS, especially at higher levels. In addition, the presence of CP and COA significantly reduced the formation of PS gel structures, especially when acting together. Furthermore, CP and COA reduced the content of rapidly digestible starch in PS and increased the content of resistant starch. Differently, CP can increase the slowly digestible starch content, whereas COA did the opposite. In the ternary composite system, CP and COA will also interact and restrict each other. Hence, the characteristics of PS can be better improved by adjusting the ratio of CP and COA. Meanwhile, the results of the study can provide potential possibilities for the application of CP and COA in food and improve the quality of PS‐related products.

Pasting, rheology, structural properties and in vitro digestibility of potato starch complexes co-gelatinized with squash polysaccharides

The effects of extraction of squash polysaccharide from water (WESP) and subcritical water (SWESP) on gelatinization, rheology, thermodynamic, micro-structure, freeze-thaw stability and digestibility of potato starch (PS) were studied. The WESP and SWESP decreased peak viscosity, trough viscosity, breakdown viscosity, final viscosity, storage modulus and loss modulus of PS. Conversely, the setback viscosity, pasting temperature and peak time increased. All gel samples belonged to the weak gel system. The thermodynamic and fourier spectroscopic results demonstrated a significant retardation of PS retrogradation in the presence of WESP and SWESP. It was consistent with the microstructure characterization detected by scanning electron microscopy that both WESP and SWESP had a significant inhibitory effect on the formation of the PS gel structure. Moreover, the existence of WESP and SWESP compromised the freeze-thaw stability of PS gel. Meanwhile, WESP and SWESP also affected the digestibility of PS and reduced the eGI value of PS, which was conducive to stabilizing blood sugar fluctuations. This study helped to better understand the interaction of PS with WESP/SWESP in the gel system, and supplied a way to improve the quality of PS-related products. In addition, it also contributed to the industrial production and application of WESP and SWESP.

Structural characterization and physicochemical properties of grain amaranth starch

With potato starch (PS) and corn starch (CS) as the controls, the structure and physicochemical properties of grain amaranth starch (GAS) and its binding with dihydromyricetin were investigated in this study. The results indicated that GAS granules were small in size (3.21 ± 0.13 μm) and had a low amylose content (11.57 ± 0.91%). GAS exhibited low paste clarity, solubility, and swelling power, but demonstrated good freeze-thaw stability and resistance to retrogradation. Although the pasting temperature of GAS was high (75.88 ± 0.03 °C), its peak viscosity, breakdown viscosity, and setback viscosity were significantly lower than those of PS and CS. GAS was classified as A-type starch, with a high molecular weight and broad distribution (Mw, 3.96 × 107 g/mol; PDI, 2.67). For its chain length distribution, chain B1 had the highest proportion (50.09%), while chain B3 had the lowest proportion (13.50%). The complexation of GAS with dihydromyricetin effectively enhanced its ABTS and DPPH free radical scavenging capacities.

Modification of gadung (Dioscorea hispida Dennst) starch by ultrasonication and freeze moisture treatment

Gadung starch (Dioscorea hispida dennst.) has several weaknesses related to its low functional properties and stability. Physical modifications of ultrasonication and Freeze Moisture Treatment (FMT) can be an alternative to improve the functional properties by forming cracks and cavities in starch. Hence, this research aimed to obtain modified gadung starch with better functional and physicochemical properties through ultrasonication and FMT. The combination of ultrasonication 30 min + FMT 70 % produced the desired characteristics. This includes the functional properties of starch, which revealed that swelling volume increased by 1.19-fold, solubility increased by 1.17-fold, and Water Absorption Capacity (WAC) increased by 1.31-fold. The stability of the starch paste was better, with a decrease in Breakdown Viscosity (BV) from 3093.50 to 2408.00 cP. The physicochemical properties exhibited that the surface of the starch granules had cracks and cavities, the starch was more amorphous, and the crystallinity decreased from 35.75 to 32.06 and the smaller ratio of the bands at 1045/1022 from 1.412 to 1.396 by FTIR spectra. However, the treatments did not cause changes in crystallinity type (B-type) and functional groups. Therefore, the combination treatment of ultrasonication and FMT effectively improved the properties by forming amorphous gadung starch.

Gadung (Dioscorea hispida) tuber starch modified by freeze moisture treatment and heat moisture treatment: a study of functional, pasting, and physicochemical properties

ABSTRACT Gadung starch has limitations in several functional properties and thermal stability. Modifying starch through temperature treatments such as Freeze Moisture Treatment (FMT) and Heat Moisture Treatment (HMT) potentially improves these weaknesses. This research aimed to determine the effects of FMT and HMT on the functional, pasting, and physicochemical properties of gadung starch. This study consisted of a variety of treatments, namely native starch, FMT, HMT 100°C, HMT 110°C, FMT + HMT 100°C, and FMT + HMT 110°C. The results showed that FMT and HMT treatments significantly affected the functional, pasting, and physicochemical properties of gadung starch. The combination modification treatment of FMT + HMT 110°C increased swelling volume by 1.44 times, and water absorption capacity increased by 1.37 times. This was confirmed by the formation of porous and amorphous starch granules. Modified starch also had the best heat stability, as indicated by a low breakdown viscosity of 31.00 ± 9.90 cP. FMT+HMT110°C modified treatment was the best treatment because it had more pores, cracks, and higher swelling volume. The starch crystallinity index of modified starch decreased from 35.75 to 31.58 and changed the crystallinity type from B-type to A-type. The starch modification did not cause changes in functional groups but reduced crystallinity as indicated by the smaller ratio of the bands at 1045/1022 and the higher ratio at 1022/995 from FTIR spectra. Thus, FMT and HMT could effectively improve the characteristics of gadung starch by forming heat-stable amorphous starch.

Use of low cost near-infrared spectroscopy, to predict pasting properties of high quality cassava flour

Determination of pasting properties of high quality cassava flour using rapid visco analyzer is expensive and time consuming. The use of mobile near infrared spectroscopy (SCiO™) is an alternative high throughput phenotyping technology for predicting pasting properties of high quality cassava flour traits. However, model development and validation are necessary to verify that reasonable expectations are established for the accuracy of a prediction model. In the context of an ongoing breeding effort, we investigated the use of an inexpensive, portable spectrometer that only records a portion (740–1070 nm) of the whole NIR spectrum to predict cassava pasting properties. Three machine-learning models, namely glmnet, lm, and gbm, implemented in the Caret package in R statistical program, were solely evaluated. Based on calibration statistics (R2, RMSE and MAE), we found that model calibrations using glmnet provided the best model for breakdown viscosity, peak viscosity and pasting temperature. The glmnet model using the first derivative, peak viscosity had calibration and validation accuracy of R2 = 0.56 and R2 = 0.51 respectively while breakdown had calibration and validation accuracy of R2 = 0.66 and R2 = 0.66 respectively. We also found out that stacking of pre-treatments with Moving Average, Savitzky Golay, First Derivative, Second derivative and Standard Normal variate using glmnet model resulted in calibration and validation accuracy of R2 = 0.65 and R2 = 0.64 respectively for pasting temperature. The developed calibration model predicted the pasting properties of HQCF with sufficient accuracy for screening purposes. Therefore, SCiO™ can be reliably deployed in screening early-generation breeding materials for pasting properties.

Genome-wide association study identifies loci and candidate genes for RVA parameters in wheat (Triticum aestivum L.).

The gelatinization and retrogradation characteristics of wheat starch affect the eating quality of Chinese-style food. Rapid Visco Analyzer (RVA) parameters have been widely used as important indicators to evaluate and improve the quality of wheat starch. However, the genetic basis of RVA parameters remains to be further explored. In the present study, a natural population was genotyped using 90K single nucleotide polymorphism (SNP) arrays, and the RVA parameters of this population grown in five environments were evaluated. The results showed that 22,068 high-quality SNP markers were identified and distributed unequally on the chromosomes. According to the genetic distance, 214 wheat materials were divided into four groups. Except for the pasting temperature (PTT), six parameters followed a normal distribution. Based on the general linear model, 969 significant association SNPs were detected by genome-wide association studies (GWAS), and chromosomes 7A and 2B had the most associated SNPs. Breakdown viscosity (BV) was associated with the most SNPs (n = 238), followed by PTT (n = 186), peak viscosity (PV; n = 156), trough viscosity (TV; n = 127), and final viscosity (FV; n = 126). According to the average linkage disequilibrium (LD), 33 stable quantitative trait loci (QTLs) were identified for single parameters in multiple environments, of which 12 were associated with BV, followed by peak time (PT; n = 8) and PTT (n = 7). On the other hand, 67 pleiotropic QTLs were identified for multiple parameters. Three candidate genes-TasbeIIa, TasbeI, and TassIIa-were screened for phenotyping analysis. The grain width and the weight of the TasbeIIa and TaSSIIa knockout (KO) lines were significantly lower than those of the TasbeI KO lines and the control (CK). The KO lines had smaller endosperm cells, smaller A-type starch granules, and higher amylose content. The TasbeI KO lines showed normal RVA curves, while the TasbeIIa KO lines showed flat curves. However, the TaSSIIa lines failed to paste under the RVA temperatures. Conclusively, the SNPs/QTLs significantly associated with the RVA parameters and genetic resources with novel haplotypes could be used to improve the quality of wheat starch.

Penalties in Granule Size Distribution and Viscosity Parameters of Starch Caused by Lodging in Winter Wheat

Granule size distribution of wheat starch is an important characteristic that could affect the functionality of wheat (Triticum aestivum L.) products. Lodging is a major limiting factor for wheat production. Few studies have been conducted to clarify how lodging influences the granule size distribution and viscosity parameters of starch in wheat grains. Two growing seasons, two high-yield winter wheat cultivars, and five artificial lodging treatments were imposed. The results indicated that lodging significantly reduced the content of starch and increased that of protein. Additionally, lodging caused a marked drop in both starch and protein yields. The relative loss of grain yield, starch yield, harvest index, and protein yield all differed remarkably among lodging treatments with a ranking of L2 > L1 > L4 > L3. Lodging also led to a reduction in the proportion (both by volume and by surface area) of B-type granules and a corresponding increase in that of A-type granules, and the more serious the lodging degree, the greater effect on the changes in these proportions. The smaller starch granules predominated in number, even though their collective contribution to the overall volume is was relatively minor. Meanwhile, it was found that the peak viscosity, hold viscosity, final viscosity, breakdown viscosity, and rebound value of wheat starch were significantly decreased by lodging. Correlation analysis showed that the peak and final viscosities were negatively correlated with volume percentages of A-type starch granules, but were positively correlated with B-type granules. This indicates that B-type granules have higher peak and final viscosities compared with A-type granules in wheat kernels. Lodging can reduce the proportion of B-type starch granules, and thus reduce the peak and the final viscosity in wheat grain.

Comparisons of Appearance and Eating Quality Traits Between Early and Late Maturing Soft Rice

Soft Japonica rice is popular in Yangtze River Delta of China in recent years because of its high eating quality. In this study, high eating quality soft Japonica rice with early and late maturity was used to analyze their eating quality traits. The appearance, texture, and physicochemical characteristics, gelatinization and pasting properties, and fine structures between early and late maturing soft rice were compared. Early maturing soft rice had higher whiteness, chalkiness, gelatinization temperature, peak viscosity, breakdown viscosity, long branch-chain amylopectin, amylopectin chains (DP > 25), and molecular weight than late maturing soft rice. The higher gelatinization and pasting properties in early maturing soft rice probably be attributed to its higher amount of long branch-chain amylopectin, proportions of amylopectin chains (DP > 25) and molecular weight, compared with late maturing soft rice. Late maturing soft rice had higher amylose content, gel consistency, short branch-chain amylopectin, amylopectin short chains (DP 6–12), setback viscosity, and consistence viscosity than early maturing soft rice. The appearance and eating quality of late maturing soft rice were significantly higher than those of early maturing soft rice.

Effect of Different Fertilizer Types on Quality of Foxtail Millet under Low Nitrogen Conditions.

In order to clarify the effect of different fertilizers on foxtail millet quality under low nitrogen conditions, we used JGNo.21 and LZGNo.2 as experimental materials and set up five treatments, including non-fertilization, nitrogen, phosphorus, compound, and organic fertilizers, to study the regulation of different fertilizer types on agronomic traits, nutrient fractions, and pasting characteristics of foxtail millet under low nitrogen conditions. Compared with the control, all of the fertilizers improved the agronomic traits of JGNo.21 to a certain extent. Nitrogen and compound fertilizer treatments reduced the starch content of JGNo.21; the starch content was reduced by 0.55% and 0.07% under nitrogen and compound fertilizers treatments. Phosphorus and organic fertilizers increased starch content, and starch content increased by 0.50% and 0.56% under phosphorus and organic fertilizer treatments. The effect of each fertilizer treatment on protein content was completely opposite to that of starch; different fertilizer treatments reduced the fat content of JGNo.21 and increased the fiber content. Among them, nitrogen and phosphorus fertilizers increased the yellow pigment content; the yellow pigment content increased by 1.21% and 2.64% under nitrogen and phosphorus fertilizer treatments. Organic and compound fertilizers reduced the content of yellow pigment; the yellow pigment content was reduced by 3.36% and 2.79% under organic and compound fertilizer treatments. Nitrogen and organic fertilizers increased the fat content of LZGNo.2; the fat content increased by 2.62% and 1.98% under nitrogen, organic fertilizer treatment. Compound and phosphorus fertilizer decreased the fat content; the fat content decreased by 2.16% and 2.90% under compound and phosphorus fertilizer treatment. Different fertilizer treatments reduced the cellulose and yellow pigment content of LZGNo.2. The content of essential, non-essential, and total amino acids of JGNo.21 was increased under compound and nitrogen fertilizer treatments and decreased under organic and phosphorus fertilizer treatments. The content of essential, non-essential, and total amino acids of LZGNo.2 was significantly higher under compound, nitrogen, and organic fertilizer treatments compared with control and significantly decreased under phosphorus fertilizer treatments. Nitrogen and compound fertilizer treatments significantly reduced the values of peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity, and pasting time of each index of JGNo.21; phosphorus and organic fertilizer treatments improved the values of each index. In contrast, the pasting viscosity of LZGNo.2 increased under phosphorus fertilizer treatment and decreased under nitrogen fertilizer treatment. Reasonable fertilization can improve the quality of foxtail millet, which provides a scientific theoretical basis for improving the quality of foxtail millet.

Modified Arrowroot Starch: Impact of Multiple Acetylation on Physical, Chemical, and Physicochemical Characteristics

Abstract Modifying single-acetylated starch in arrowroot starch has improved starch quality, especially in paste clarity properties. It was conducted to determine the effect of the double acetylation modification method on the physical, chemical, and physicochemical characteristics of modified arrowroot starch. It used a completely randomized design with variations in the concentration of acid acetate and the immersion time of single acetylation modification. The best single Acetylated Starch is the treatment of variations in adding 2% acetic acid concentration for 60 minutes soaking time, which then proceeds with double acetylation modification. Double acetylation has a paste clarity level of 25.02%, moisture content of 13.33%, Amylose Content of 30.62%, Water Absorption of 3.77 g/g, Swelling power of 9.30 g/g, and Solubility of 5.19%. The pasting properties have a Peak Viscosity of 5716 cP, Through Viscosity of 2336 cP, Breakdown Viscosity of 3380 cP, Final Viscosity of 2750 cP, Setback Viscosity of 414 cP, Peak Time of 5 minutes, and Pasting Temperature 70.90°C. The dual acetylation improves the solubility and swelling power compared with single acetylation and unmodified starch.

Characteristics of sorghum flour modified with physical and enzymatic treatments

This study evaluated the physicochemical and thermal properties of modified sorghum flour. The modified sorghum flour was obtained through extrusion -enzymatic treatment using thermostable-α amylase at various feed moisture levels. The results showed that unmodified sorghum flour had the average chemical composition of sample being 87.06% carbohydrate, 9.8% protein, 0.32% fat and 0.64% ash. The unmodified and modified sorghum flour differed in their properties. The swelling power and solubility changed from 16.21 (g/g) to 4.64(g/g) – 28.20 (g/g) and from 4.68% to 4.25%–83.81% respectively. A wide range of pasting properties were noticed, such as peak viscosity (54 cP-3028 cP), breakdown viscosity (59 cP-1029 cP), setback viscosity (-106.50–2351 cP). Peak viscosity was not detected when the modification was performed at high feed moisture (FM 35%) treatment combined with the addition of thermostable-αamylase. Additionally, the onset, peak, and conclusion temperatures of gelatinization, and the enthalpies of modified flours were lower than those of unmodified ones. Morphological changes in the surface of starch granules were noticed as shown by pore formation through SEM observation. This study provided insights into the future direction of extrusion combined with enzymatic treatment for the selective modification of sorghum flour functional properties.

Microwave treatment enhances the physical and sensory quality of quinoa-enriched gluten-free bread

The suitability of microwave-assisted hydrothermally treated (MWT) quinoa flour was investigated as an ingredient for enhancing the quality of gluten-free (GF) bread fortified with quinoa. Different levels (0%, 25%, 37.5%, 50%, and 75%) of native/untreated (N) or MWT quinoa flour (30% moisture content, 9 W/g, total 8 min of microwave exposure) were evaluated to replace maize starch in a starch-based GF recipe. The hydration of the dough was adjusted to obtain similar consistency in terms of complex modulus, G1*, to compensate its increase due to quinoa addition and treatment (up to +737%). The incorporation of increasing amounts of native quinoa flour reduced dough viscosimetric profiles, delayed its gelatinization peak in DSC scans (up to +3.4 °C), and decreased the dough's development and stability during the fermentation test (the final height decreased from 88 mm for 0% quinoa to 4 mm for 75%). When substituting native by MWT quinoa flour at a certain substitution level, a reduction in the breakdown viscosity, an increase in pasting temperature, and an increase in dough development and stability during the fermentation test were noted. As a result, the MWT quinoa flour-fortified breads exhibited a higher specific volume, lower hardness, and retarded staling. In addition, sensory evaluation of the breads showed a reduction in the herbaceous off-flavour associated with the quinoa (untreated) flour, and no effect on bitterness. The experimental findings indicate the feasibility of using microwave hydrothermal treatment to improve the physical properties and sensory quality of quinoa-enriched GF bread.

Effect of Bambara Groundnut Flour (Vigna subterranea) Inclusion on the Functional, Pasting, Physical and Proximate Properties of Composite Cassava-bambara Flour

This study evaluated the effect of Bambara groundnut flour inclusion on the functional, pasting, physical properties and proximate compositions of composite flour (CF) from cassava and Bambara groundnut. Cassava variety (IITA-TMS-IBA011368) and Bambara groundnut were processed into flour and blended together based on D-Optimal mixture design with an outcome of eight experimental samples using Design Expert Software (Version 12.0). The flour blends were analyzed for functional, pasting, physical properties (color), baking strength and proximate composition. Data obtained were analyzed using analysis of variance and means were separated using Ducan’s Multiple Range Test. Range of results for bulk density, water absorption capacity, swelling index, solubility index and oil absorption capacity of the composite flour are 0.64-0.80g/mL, 0.38-1.37%, 0.77-0.91%, 6.00-8.65, 1.58-2.97, respectively. The peak viscosity, trough, breakdown viscosity, final viscosity, setback viscosity, peak time and pasting temperature ranged from 162.84±2.09 to 426.50±1.83 RVU, 77.96±2.71 to 195.59±8.91 RVU, 84.88±0.63 to 234.75±5.58 RVU, 158.92±4.34 to 293.17±1.34 RVU, 76.88±18.04 to 101.42±5.08 RVU, 4.10±0.03 to 5.93±0.00 min and 75.05±0.05 to 94.78±0.38 oC, respectively. The baking strength characteristics of the flour blends such as moisture, ash, color, wet gluten, zenleny dry protein and wet protein ranged from 11.55 to 12.55%, 0.50 to 1.25%, 88.65 to 90.55, 8.35 to 13.80, -2.35 to 41.25, 4.92 to 13.85% and 4.53 to 11.99 %, respectively. Moisture, ash, fibre, fat, protein and carbohydrate of the composite flour ranged from 7.57 to 11.87%, 0.42 to 2.40 %, 1.78 to 3.00%, 2.81 to 5.62%, 8.42 to 12.68% and 67.61 to75.99%, respectively. Flour lightness, redness and yellowness ranged from 33.22 to 54.10, -2.89 to-1.14, 5.94 to 9.35, respectively. The inclusion of Bambara groundnut flour had a significant effect on the functional (swelling index, water and oil absorption capacity), pasting (peak, trough and final viscosity) and proximate (ash, fat and carbohydrate) properties of the flour blends.