Physicochemical and antioxidant properties of dietary fibers from Qingke (hull-less barley) flour as affected by ultrafine grinding

Cereal β-d-Glucans in Food Processing Applications and Nanotechnology Research

Cereal (1,3)(1,4)-β-d-glucans, known as β-d-glucans, are cell wall polysaccharides observed in selected plants of grasses, and oats and barley are their good natural sources. Thanks to their physicochemical properties β-d-glucans have therapeutic and nutritional potential and a specific place for their functional characteristics in diverse food formulations. They can function as thickeners, stabilizers, emulsifiers, and textural and gelation agents in beverages, bakery, meat, and extruded products. The objective of this review is to describe the primary procedures for the production of β-d-glucans from cereal grains, to define the processing factors influencing their properties, and to summarize their current use in the production of novel cereal-based foods. Additionally, the study delves into the utilization of β-d-glucans in the rapidly evolving field of nanotechnology, exploring potential applications within this technological realm.

Effects of pre-drying treatment and particle sizes on physicochemical and structural properties of pumpkin flour

The objective of this study is to investigate the effect of pre-drying treatment and particle size on pumpkin flour's compositional, functional, pasting, thermal, and structural properties. Pre-drying treatment and reducing the size of particles have led to an increase in the levels of crude fiber, phytochemicals, and functional properties. However, the amounts of moisture and lightness of color decreased with pretreatment, but improved with particle size reduction. Among the samples, those that were finely milled after pre-treatment showed the highest viscosities, while the untreated samples that were coarsely milled had lower viscosities. The pre-drying treatments yielded notable reductions in both gelatinization temperature and enthalpy of the flour matrix, in comparison to untreated flours. FTIR analysis has indicated that no new functional groups were produced. XRD analysis suggests that while pre-drying treatment leads to decreases in crystallinity index, fine milling leads to increments. The morphological pattern suggested that pretreatment effectively altered the original surface structure of the flour, but particle size reduction did not.

Impact of supplement of Qingke flours on physiochemical properties, sensory and in vitro starch digestibility of wheat bread and its enhancement by bread quality improvers

The aim is to upgrade the formulation to produce wheat bread with lower starch digestibility by supplemented with Qingke flour. Physiochemical properties of multi-scale Qingke flours were examined to select the most satisfied Qingke flour for breadmaking. Data showed multi-scale Qingke samples differed in total starch content, water/oil binding capacity, freeze-thaw stability, but had similar swelling capacity and thermodynamic properties. Addition of Qingke flours significantly reduced the total in vitro starch digestion of bread from 80% to 41% and decreased the rapidly digested starch content from 53% to 27%. However, Qingke flours caused a worse bread quality, texture and sensory e.g. lower bread specific volume (4.26-3.3 mL/g), larger hardness (398-1170 g) and chewiness (296-707 mJ). Meanwhile, hydroxypropyl methylcellulose, sodium stearoyl lactylate and transglutaminase could improve the bread quality and sensory. Lastly, results revealed Qingke-supplemented bread could generate new volatile compounds, hence having a different aroma compared to original wheat bread.

Effects of Highland Barley Flour with Different Particle Sizes on the Characteristics of Reconstituted Flour and Noodles

To study the effects of highland barley flour with different particle sizes on dough characteristics and noodle quality, highland barley flours (median particle sizes of 223.25, 143.12, 90.73, 42.33 and 19.26 μm, respectively) were mixed with the wheat flour to make noodles. The damaged starch content of highland barley flour with five particle sizes was 47.0, 61.0, 62.3, 102.0, and 108.0 g/kg, respectively. The reconstituted flour containing highland barley powder with smaller particle sizes showed higher viscosity and water absorption. The smaller the particle size of barley flour, the lower the cooking yield, shear force and pasting enthalpy of the noodles, and the higher the hardness of the noodles. As the particle size of barley flour decreases, the structural density of the noodles increases. This study is expected to provide a constructive reference for the development of barley-wheat composite flour and the production of barley-wheat noodles.

Modified highland barley regulates lipid metabolism, liver inflammation and gut microbiota in high-fat/cholesterol diet mice as revealed by LC-MS based metabonomics

Highland barley (HB) displays a series of properties including regulation of lipid metabolism and attenuation of liver injury. Our study aimed to investigate the effect of modified highland barley (MHB) including fluidized highland barley (HB-1), extruded and puffed highland barley (HB-2), and ultrafine pulverized highland barley (HB-3) on lipid metabolism, liver inflammation, gut microbiota and metabolite profiles in mice fed with a high-fat/cholesterol diet (HFCD). 6 treatment groups were fed a normal control diet or an HFCD with or without MHB supplementation for 10 weeks. Results showed that MHB significantly improved lipid parameters, liver function and injury and blood glucose indexes related to hyperlipidemia compared with the HFCD group. In addition, MHB recovered the disorder of gut microbiota by increasing the Bacteroidetes/Firmicutes ratio and Lactobacillus and Allobaculum abundances and decreasing Proteobacteria abundance related to lipid metabolism bacteria. MHB reversed the decrease of short-chain fatty acid levels caused by the HFCD. Fecal metabolomics analysis showed that the important differential metabolites between HB-1 and HFCD were deoxycholic acid, myclobutanil and dibutyl phthalate, and the important differential metabolic pathways were arachidonic acid metabolism, ABC transporters and biosynthesis of unsaturated fatty acids. Results suggested that MHB especially HB-1 were better effective dietary intervention candidates to ameliorate hyperlipidemia compared with HB.

Impact of high-pressure homogenization on the microstructure and rheological properties of citrus fiber

Citrus fiber dispersion with different concentrations (5–25 g/kg) was treated by high-pressure homogenization (90 and 160 MPa) for two cycles. The particle size distribution, hydration properties of powders, morphology and rheological measurements were carried out to study the microstructure and rheological properties changes by high-pressure homogenization (HPH). In conclusion, the HPH can reduce the particle size of fiber, improve the water holding capacity and water binding capacity. Furthermore, fiber shape can be modified from globular cluster to flake-like slices, and tiny pores can be formed on the surface of citrus fiber. The apparent viscosity, storage modulus and loss modulus were increased by HPH whereas the activation energy was reduced. The Hershcel–Bulkley model, Carreau model and Power Law mode were selected to evaluate the rheological properties.

Nutritional value of barley cereal and better opportunities for its processing as a value-added food: a comprehensive review

Barley is one of the most important cereal crops and arranged globally as fourth after wheat, rice, and corn. It is known for its beneficial effects against degenerative diseases including diabetes, obesity, hypertension, and colon inflammation which are associated with eating habits and improper lifestyles. These effects are mainly attributed to its rich dietary fibers, i.e., β-glucan composition. Moreover, barley considered as a good source of starch, minerals, vitamins, and protein pose it as an ideal food supplement. Nevertheless, about 2% of the barley global production is utilized due to unacceptable organoleptic characters. Therefore, continuous modifications are ongoing either to develop new cultivars for different purposes, or novel processing methods to improve its organoleptic characters. In this review, we provide a comprehensive overview of the macroconstituents and microconstituents of barley, its nutritional value and prebiotic effects. Further, different processing procedures performed to improve its organoleptic characters or to decrease its antinutrient levels are outlined with suggestions for further needed cultivars that could preserve the different benefits of barley and maximize its value as a major cereal crop.

Modification of sweet potato (Ipomoea batatas Lam.) residues soluble dietary fiber following twin-screw extrusion

Effect of twin-screw extrusion on soluble dietary fiber (SDF) from sweet potato residues (SPRs) were investigated using optimized conditions, at screw speed of 180 rpm, feed rate at 17 Hz, feed moisture at 40% and extrusion temperature at 150 °C. Extruded SDF, showed higher SDF levels (9.63%-29.25%), cholesterol and sodiumcholate adsorption capacity, radical scavenging capacity, and inhibition of digestive enzymes. Moreover, extrusion effectively reduced particle size and molecularweight of SDF, modulated monosaccharide ratios, and increased water retention capacity (WRC), oil retention capacity (ORC), swelling capacity (SC) and glucose absorption capacity (GAC). Additionally, scanning electron microscopy (SEM) demonstrated decomposition of macromolecules of SDF to smaller fractions and formation of a porous morphology following extrusion. Furthermore, the extruded SDF increased thermal stability as determined by differential scanning calorimetry (DSC). Overall, the SDF from SPRs with improved functional and physiochemical properties could be used as a functional additive in diverse food products.

Effects of superfine grinding on asparagus pomace. Part I: Changes on physicochemical and functional properties

The effects of superfine grinding on the physicochemical and functional properties of asparagus pomace were investigated. The results showed that in terms of the specific surface area, water solubility, soluble dietary fiber content, and ratio of insoluble dietary fiber to soluble dietary fiber, finer samples usually possessed better physicochemical properties compared with coarse samples. However, grinding samples excessively to produce small particle sizes could reduce the water-holding capacity, oil-binding capacity, and swelling capacity. In addition, the extraction of both free and bound phenolics in asparagus pomace powder samples and the samples' absorption of both nitrite ion and glucose showed typical bell-shaped curves, demonstrating that superfine grinding could significantly impact the various properties of asparagus pomace. This study should provide insights into the effect of micronization on the functionalities of fiber-rich food materials. PRACTICAL APPLICATION: This article deals with the effects of superfine grinding on the physicochemical and functional properties of asparagus pomace. The results showed that the properties of asparagus pomace did not always improve gradually with decreasing particle size. With a decrease in granularity, some parameters showed a bell-shaped curve whereas others initially increased and then stabilized, indicating that in actual production, the crushing particle size should be determined according to actual needs or target parameters.

Effect of thermal stabilization on physico-chemical parameters and functional properties of wheat bran

The food industry also focuses on the use of by-products from food processing. Wheat bran is a valuable by-product of the wheat milling process, which is rich in dietary fiber. In addition to nutritional value, dietary fiber has a functional potential in the production of novel foods. Pre-treatment of the dietary fiber using different methods can change its functional properties. The objective of this study was to evaluate the effect of stabilization process on physico-chemical parameters and functional properties of wheat bran. Wheat bran from two wheat variety was treated using microwave and hot air heating. It was observed that wheat bran included more than 45% of total dietary fiber. Results suggested that treatment of bran using both method increased total dietary fiber content. Thermal treatment process decreased the anti-nutritional agent in bran samples. Phytic acid content diminishing of 44% and 49% was observed in microwave treated bran samples. Moreover, treatment of bran using a hot air heating improved the hydration properties (water holding, water retention and swelling capacity), while oil holding capacity was not significantly altered. Treatment decreased the antioxidant activity of treated bran samples. It was observed that thermal treatment modified the color parameters of bran (lightness, yellowness and hue angle decreased and redness and Chroma increased).

Effect of superfine grinding on the physicochemical properties of bulbs of Fritillaria unibracteata Hsiao et K.C. Hsia powder

This work aimed to determine the influence of superfine grinding on the physicochemical properties of bulbs of Fritillaria unibracteata Hsiao et K.C. Hsia (BFU) powder. For this purpose, fine powder (FP) and two superfine powders (SPs) were obtained via superfine and conventional grinding methods. The properties of different powders were studied and compared. Compared with FP, SPs exhibited higher values in terms of the angle of repose, swelling capacity, ethanol extraction yield, total alkaloid content, and imperialine content, while lower values in terms of particle size and bulk density. Especially, the total alkaloid content of SP-I increased by 66.7%. Proper grinding is more conducive to reduce particle size and improve alkaloid content. FTIR analysis indicates that no new functional groups produced after superfine grinding. XRD analysis suggests that grinding treatment lead to decreases in the crystallinity. Therefore, superfine grinding displays immense potential in the BFU application.

Time-Course Comparative Metabolite Profiling under Osmotic Stress in Tolerant and Sensitive Tibetan Hulless Barley

Tibetan hulless barley is widely grown in the extreme environmental conditions of the Qinghai-Tibet Plateau which is characterized by cold, high salinity, and drought. Osmotic stress always occurs simultaneously with drought and its tolerance is a vital part of drought tolerance. The diversity of metabolites leading to osmotic stress tolerance was characterized using widely-targeted metabolomics in tolerant (XL) and sensitive (D) accessions submitted to polyethylene glycol. XL regulated a more diverse set of metabolites than D, which may promote the establishment of a robust system to cope with the stress in XL. Compounds belonging to the group of flavonoids, amino acids, and glycerophospholipids constitute the core metabolome responsive to the stress, despite the tolerance levels. Moreover, 8 h appeared to be a critical time point for stress endurance involving a high accumulation of key metabolites from the class of nucleotide and its derivative which provide the ultimate energy source for the synthesis of functional carbohydrates, lipids, peptides, and secondary metabolites in XL. This intrinsic metabolic adjustment helped XL to efficiently alleviate the stress at the later stages. A total of 22 diverse compounds were constantly and exclusively regulated in XL, representing novel stress tolerance biomarkers which may help improving stress tolerance, especially drought, in hulless barley.

Effect of particle size on phytochemical composition and antioxidant properties of two persimmon flours from Diospyros kaki Thunb. vars. 'Rojo Brillante' and 'Triumph' co-products

BACKGROUND

This contribution studies the influence of the particle size of persimmon flours (from two cultivars, 'Rojo Brillante' and 'Triumph') on their primary (sugars and organic acids) and secondary (polyphenols, flavonoids and carotenoids) metabolite content, and also on their antioxidant activity, to assess whether these flours could find applications in the food industry as a potential functional ingredient.

RESULTS

The main sugars were fructose and glucose and the principal organic acid was malic acid. The highest content of total phenols, flavonoids and carotenoids was found in flour fractions from cv. 'Rojo Brillante'. The phenol profile determined by HPLC identified six phenolic compounds in both persimmon flours, the most abundant being gallic acid. The greatest ABTS and DPPH radical scavenging capacity and ferric reducing power were found in flour fractions from cv. 'Rojo Brillante'. Although the influence of particle size on all these properties was not always evident, in general, the higher bioactive compound content and antioxidant capacity were in the finest particles.

CONCLUSION

Co-products from cvs. 'Rojo Brillante' and 'Triumph' persimmon juice extraction can be processed to obtain flours rich in sugars, organic acids and bioactive compounds, suggesting their possible use as a functional ingredient (with antioxidant properties) in different food products. © 2017 Society of Chemical Industry.

Physical and Viscoelastic Properties of Different Moisture Content Highland Barley Kernels

The study is conducted to investigate the physical and viscoelastic properties of the highland barley kernels in different moisture content range from 10.1 %% to 20.5 %% (w.b.). Highland barley kernel samples were selected with physical properties in terms of length, width, thickness, 1000-kernel weight, volume, geometric and arithmetic mean diameter changing in linear trends. By using a dynamic mechanical analyzer, the 4-element Burgers model was found to adequately represent the creep behavior of the highland barley kernels (R2> 0.977). The creep behavior of the ventral groove and dorsal side was also matched perfectly with Burgers model (R2> 0.946). The creep behavior of these kernels at long-time frame was studied applying time-temperature superposition (TTS). TTS method was successfully used to predict the creep behavior of these kernels at longer frame of time. TheTgvalues for the kernels decreased with increasing moisture content. TheTgvalues for the kernels at the moisture contents of 10.1 %%and 20.5 %% were 114.33 °C and 67.95 °C, respectively. The magnitude of the storage modulus, loss tangent and their change rates with frequency were maximum at 10.1 %% and minimum at 20.5 %% moisture contents.

Application and Development Prospects of Dietary Fibers in Flour Products

Dietary fibers are often characterized by high nutritional quality, as they are able to cure many chronic diseases and improve texture, sensory characteristics, and shelf life of foods. Here, the following aspects of dietary fibers have been reviewed: nutritional properties, including the ability to regulate blood sugar levels, effects on microorganisms, antioxidant effect, potential role in losing weight, ability to regulate blood lipids, application in flour products such as bread and Chinese noodles, challenges such as dark color, rough texture, and poor solubility, and potential solutions that include modification methods. The primary purpose of this review is to comprehensively evaluate potential applications of dietary fibers in flour products, addressing common problems and reviewing potential solutions to promote further study and applications of dietary fibers.