Combined ultrasound and germination treatment on the fine structure of highland barley starch

Highland barley is a grain crop grown in Tibet, China. This study investigated the structure of highland barley starch using ultrasound (40 kHz, 40 min, 165.5 W) and germination treatments (30℃ with 80% relative humidity). The macroscopic morphology and the barley's fine and molecular structure were evaluated. After sequential ultrasound pretreatment and germination, a significant difference in moisture content and surface roughness was noted between highland barley and the other groups. All test groups showed an increased particle size distribution range with increasing germination time. FTIR results also indicated that after sequential ultrasound pretreatment and germination, the absorption intensity of the intramolecular hydroxyl (-OH) group of starch increased, and hydrogen bonding was stronger compared to the untreated germinated sample. In addition, XRD analysis revealed that starch crystallinity increased following sequential ultrasound treatment and germination, but a-type of crystallinity remained after sonication. Further, the Mw of sequential ultrasound pretreatment and germination at any time is higher than that of sequential germination and ultrasound. As a result of sequential ultrasound pretreatment and germination, changes in the content of chain length of barley starch were consistent with germination alone. At the same time, the average degree of polymerisation (DP) fluctuated slightly. Lastly, the starch was modified during the sonication process, either prior to or following sonication. Pretreatment with ultrasound illustrated a more profound effect on barley starch than sequential germination and ultrasound treatment. In conclusion, these results indicate that sequential ultrasound pretreatment and germination improve the fine structure of highland barley starch.

Influence of the Addition of Vital Wheat Gluten on Thermal and Rheological Properties of Triticale Flour

The aim of this study was to evaluate the effect of the addition of vital wheat gluten to triticale flour on its thermal and rheological properties. In the tested systems (TG), triticale flour from Belcanto grain was replaced with vital wheat gluten in the amounts of 1%, 2%, 3%, 4% and 5%. Wheat flour (WF) and triticale flour (TF) were also tested. For the tested flours and mixtures with gluten, the falling number, gluten content, as well as the parameters of gelatinization and retrogradation characteristics using differential scanning calorimetry (DSC) and characteristics of pasting using a viscosity analyzer (RVA) were determined. In addition, viscosity curves were plotted, and viscoelastic properties of the obtained gels were also assessed. It was observed that there were no statistically significant differences between the TF and TG samples in terms of falling number. The average value of this parameter in TG samples was 317 s. It was found that the replacement of TF with vital gluten reduced the gelatinization enthalpy and increased the retrogradation enthalpy, as well as the degree of retrogradation. The highest viscosity was characterized by the WF paste (1784 mPa·s) and the lowest by the TG5% mixture (1536 mPa·s). Replacing TF with gluten resulted in a very visible decrease in the apparent viscosity of the systems. In addition, the gels based on the tested flours and TG systems had the character of weak gels (tan δ = G″/G' > 0.1), while the values of the parameters G' and G″ decreased as the share of gluten in the systems increased.

Non-destructive characterization of pulse flours-A review

The consumption of plant-based proteins sourced from pulses is sustainable from the perspective of agriculture, environment, food security, and nutrition. Increased incorporation of high-quality pulse ingredients into foods such as pasta and baked goods is poised to produce refined food products to satisfy consumer demand. However, a better understanding of pulse milling processes is required to optimize the blending of pulse flours with wheat flour and other traditional ingredients. A thorough review of the state-of-the-art on pulse flour quality characterization reveals that research is required to elucidate the relationships between the micro- and nanoscale structures of these flours and their milling-dependent properties, such as hydration, starch and protein quality, components separation, and particle size distribution. With advances in synchrotron-enabled material characterization techniques, there exist a few options that have the potential to fill knowledge gaps. To this end, we conducted a comprehensive review of four high-resolution nondestructive techniques (i.e., scanning electron microscopy, synchrotron X-ray microtomography, synchrotron small-angle X-ray scattering, and Fourier-transformed infrared spectromicroscopy) and a comparison of their suitability for characterizing pulse flours. Our detailed synthesis of the literature concludes that a multimodal approach to fully characterize pulse flours will be vital to predicting their end-use suitability. A holistic characterization will help optimize and standardize the milling methods, pretreatments, and post-processing of pulse flours. Millers/processors will benefit by having a range of well-understood pulse flour fractions to incorporate into food formulations.

Chemical Modifications of Normal and Waxy Potato Starches Affect Functional Properties of Aerogels

Aerogels are of increasing interest because of their exceptionally large surface area, porous structure, and low weight. Despite the significant increase in interest in the subject of starch-based aerogels, the number of detailed studies is rather scarce, which is especially evident in the case of chemically modified derivatives. Therefore, the study aims to evaluate the physicochemical properties of aerogels from chemically modified potato starch preparations (E 1422 and E 1450) obtained both from normal and waxy starches. Aerogels were prepared through the retrogradation of starch pastes followed by the gradual replacement of water with ethyl alcohol. The obtained preparations were characterized in terms of their bulk density, oil-binding capacity, as well as the texture and rheological properties of the formed pastes. Moreover, their usefulness was evaluated in an emulsion system employing rheological and low-field NMR methods. The obtained aerogels were characterized by a lower bulk density of 0.18-0.59 g/cm³ and 5.4-6.6 times higher oil-binding capacity compared to native potato starch. The chemical modification of starch helped to further alter the functional properties of the obtained aerogels, making them more effective oil binders, emulsifiers, and stabilizers (increasing the stability from 55 to 90%), which was especially evident for E 1450 preparation. Amylose content improved the aerogel properties, as waxy preparations were characterized by worse functional properties with the only exception of improved thickening ability. The most beneficial properties for the preparation of emulsions were observed for the aerogel obtained based on E 1450 normal potato starch.

Assessment of the Starch-Amylolytic Complex of Rye Flours by Traditional Methods and Modern One

The properties of the starch-amylolytic complex of commercial low-extract rye flour were determined based on the traditional method, such as falling number and amylograph test as well as differential scanning calorimetry (DSC). The starch, pentosans and protein had a significant effect on the thermal properties of the tested rye flours. Based on the falling number, it was revealed that rye flours were characterized by medium and low alpha-amylase activity. The falling number and amylograph test are not sufficient methods to determine the suitability of currently produced rye flours for bread making. The gelatinization process of the rye flour starch could be evaluated by the DSC test, which, together with the falling number and amylograph test, may allow a better way to evaluate the usefulness of rye flours for bread making. Many significant correlations between parameters determined by DSC endotherm and quality parameters of rye bread, such as volume and crumb hardness, were reported. Breads made from flour with higher enthalpy in DSC were characterized by higher volume and softer crumb.

Molecular Analysis of Retrogradation of Corn Starches

Changes of the molecular dynamics of water in 5% corn starch pastes and 5% systems composed of starch and non-starchy hydrocolloid were studied during short and long term retrogradation. Low Field NMR was used to record mean correlation times (τc) of water molecules. This molecular parameter reflects the rotation of water molecules within the network of paste. Starches of different amylose and amylopectin content were selected for this study. Comparison of the changes of τc shows how particular polymers bind water molecules. During 90 days of storage, over 50% increase in mean correlation time was recorded in pastes of starches with high amylose content. This suggests that the formation of polymeric network is controlled by amylose to which water is binding. Amylopectin was found to influence the mobility of water in the pastes to a lesser extent with changes in mean correlation times of approximately 10-15% over 90 days. On retrogradation, amylopectin, Arabic and xanthan gums hindered the formation of solid phase structures. Guar gum evoked an increase in mean correlation times of approximately 40-50% during the prolonged process of changes of the molecular dynamics of water. This indicates continued expansion of the polymeric network. Mean correlation time available from spin-lattice and spin-spin relaxation times can be useful in the analysis of the rotational vibrations of the water molecules in biopolymeric structures.

Starch as a Green Binder for the Formulation of Conducting Glue in Supercapacitors

This work describes the use of commercially available starch as a binder for the preparation of conductive glue and electrode materials. It is demonstrated that starch can be successfully implemented as a binder in energy storage systems with non-aqueous electrolytes. These devices are characterized by a stable cycle life (for 50,000 cycles) at a nominal voltage of 2.5 V. Moreover, the use of starch-based conductive glue improves the electrochemical performance, especially reducing the internal resistance of the device. Starch-bound electrodes display lower equivalent distributed resistance (EDR) values than electrodes using carboxymethylcellulose (CMC) as the binder. This is due to the noticeably lower pore clogging by starch. An electric double-layer capacitor (EDLC) in organic electrolyte (1 mol L⁻¹ TEABF₄ in ACN) at a nominal voltage of 2.5 V can reach a specific power and energy of 100 kW kg⁻¹ and 12 Wh kg ⁻¹, respectively. This study shows that starch-based conductive glues and electrode materials can be incorporated in EDLC systems.

Production of wheat bread with spray-dried potato juice: Influence on dough and bread characteristics

Spray-dried potato juice, a raw material with pro-health properties that have already been described in recent literature, was used to substitute a part of wheat flour in bread. Bread was chosen based on its popularity. This paper is a report on the results of this substitution. Three levels of flour replacement were chosen - 2.5, 5.0 and 7.5% (with respect to the mass of flour). The influence of potato juice addition on some of the most important characteristics of wheat bread was determined. Mixes of wheat flour and spray-dried potato juice were analyzed for fermentative and pasting properties. Baked bread samples were analyzed for their texture, color, consumer acceptance and antioxidant activity. The substitution influenced the volume of the loaf as gasses were not retained by the underdeveloped gluten network. Spray-dried potato juice was also found to influence the pasting properties. The viscosity values (peak viscosity, trough and final viscosity) determined with the RVA device were increased in pastes obtained from raw material mixtures with spray-dried potato juice. These crumb also showed increased firmness and chewiness as well as decreased springiness in the performed texture profile analyses. Spray-dried potato juice was also found to impact the color of bread crumb to an extent noticeable to the human eye. The bread that contained spray-dried potato juice was darker than bread produced with sole wheat bread. The color components (CIE L*a*b*) were shifted toward red and yellow. The bread containing spray-dried potato juice was also significantly richer in antioxidant compounds than the control wheat bread. From the perspective of consumer acceptance, the introduction of larger amounts of spray-dried potato juice resulted in deterioration of the sensory quality. Nonetheless, the acceptance of bread with 2.5% of flour substituted with spray-dried potato juice did not differ significantly from the control.

Rheological characterisation of gluten from triticale (x Triticosecale Wittmack)

BACKGROUND

Triticale gluten still remains very poorly characterised rheologically. In this study the mechanical spectra of gluten isolated from four triticale cultivars were registered and fitted with Cole-Cole functions yielding the visco-elastic plateau parameters. Master spectra were calculated. A retardation test was performed and used to calculate the composite mechanical spectra and the width of visco-elastic plateau l. Protein fractional composition of triticale flour and gluten was studied using capillary zone electrophoresis.

RESULTS

Differentiated HMW-GS/SS compositions were identified in the triticale cultivars studied. The rheological parameters reached the following values: J_N⁰ 1.05·10^-3 to 2.69·10^-3 Pa^-1 , G_N⁰ 372 to 956 Pa, ω₀ 0.003 to 0.06 rad s^-1 , l 169 to 3121, J_e⁰ 1.57·10^-3 to 5.03·10^-3 Pa^-1 , G_e⁰ 199 to 637 Pa and η₀ 1.06·10⁷ to 3.93·10⁷ Pa s.

CONCLUSIONS

Visco-elastic properties of triticale gluten correspond to the lower end of medium visco-elasticity shown by common wheat gluten. Master spectra and the composite mechanical spectra prove that four triticale glutens exhibit practically an identical type of visco-elastic behaviour of a biopolymeric visco-elastic liquid similar to wheat gluten. The visco-elastic plateau parameters G_N⁰ , J_N⁰ , ω₀ and l appeared significantly correlated with the contents of prolamins and secaloglutenins in triticale flours and glutens. © 2017 Society of Chemical Industry.

Triticale: Nutritional composition and food uses

Triticale (× Triticosecale Wittmack), a man-made cereal from wheat and rye hybridization, is mainly used as animal feed. In recent years, there has been increasing interest in utilising triticale for food production. Some chemical constituents (e.g., starch and non-starch polysaccharides) of triticale as well as the genetic variability in nutritional composition have been much studied. Various food and beverage products of triticale have been developed, including bakery products (e.g., bread and cookie), pasta, malt, spirit, yoghurt, and biodegradable and edible films. Focusing on the literatures from the last 5years, this mini-review summarises the recent advances in the nutritional composition and diverse food uses of triticale. There is a wide variation in the chemical composition of triticale, which suggests the potential of triticale asa cereal alternative for various food and beverage applications.