V-type Pattern Research Articles

Single helix in V-type starch carrier determines the encapsulation capacity of ethylene.

V-type starch carriers with different single helix contents were prepared using alcoholic-alkaline treatment followed by ethanol precipitation. Ethylene gas was entrapped into V-type starch carriers using a solid encapsulation method. The morphological and structural properties of inclusion complexes (ICs) were characterized using scanning electron and light microscopy, X-ray diffractometry, 13C solid-state nuclear magnetic resonance (NMR) and Raman spectroscopy. Aqueous ethanol treatment resulted in swelling and aggregation of starch granules, and B-type diffraction reflections were either reduced or completely lost with evolution of V-type pattern. Ethylene concentrations in ICs vary from 15.4% to 23.6% (w/w), which was positively correlated with the single helix content in V-type starch carriers. The formation of ICs was confirmed by appearance of the characteristic peak associated with ethylene molecule on the 13C NMR (123.14ppm) and Raman (1630cm-1) spectra. For the first time, we demonstrated that the single helix in V-type starch carrier determines the encapsulation capacity of ethylene.

Structure, physicochemical and in vitro digestion properties of ternary blends containing swollen maize starch, maize oil and zein protein

Three-component blends (TCBs) were prepared with maize starch (MS), maize oil (MO) and zein protein (ZP) through high-speed homogenization and heat treatments. The objective of this study was to understand the thermal treatment effect on the structural, physicochemical and digestion properties of the TCBs, providing guidance for designing low GI foods with higher slowly digestible- and resistant- starch. From the images of confocal laser scanning and scanning electron microscopy, ZP was mainly located on the surface of starch granules. Thermal analysis showed that a decreased enthalpy change is associated with higher treatment temperature due to the loss of the double helices of amylopectin. The high-speed homogenization and heat treatments changed the X-ray crystalline pattern of starch from the A-type to a mixture of the A- and V-type pattern. The TCBs displayed a decreased peak viscosity and an increased pasting temperature, compared with the MS alone. For the first time, we demonstrated that heating treatment at 40 °C can result in the lowest rapidly digestible starch fraction for both uncooked and cooked TCBs.

An investigation on the relationship between return and trading volume: asymmetric V-type or asymmetric increasing-type pattern

This paper develops a new mechanism that takes into account the fast change in behaviours of futures returns and trading volumes in order to model the time-varying and quantile-varying dependence between return and volume for energy-related futures products traded on TOCOM, NYMEX and ICE Futures Europe. A logistic function with the product of one-step-ahead expectations of return and volume as a transition variable is used to depict the time-varying weight of a mixture copula. This paper then employs a mixture copula of a Gumbel copula and a rotated Gumbel copula to detect the asymmetric V-type pattern and uses a mixture copula of a Gumbel copula and a survival Gumbel copula to measure the asymmetric increasing-type pattern. Empirical results demonstrate that the asymmetric V-type pattern is a more appropriate specification to characterize the return–volume nexus than the asymmetric increasing-type pattern, irrespective of the types of energy-related futures products and futures exchanges. The time-varying dependence has greater dependence in the lower–upper corner of the joint distribution than in the upper–upper corner of the joint distribution, implying that market participants believe that market reversals are more likely during periods of price declines than in periods of price increases. Moreover, this paper shows the inappropriateness of the two-step estimation method that has been widely used in the existing literature.

Effects of chemical and enzymatic modifications on starch-linoleic acid complex formation

This study investigated the complexation yield and physicochemical properties of soluble and insoluble starch complexes with linoleic acid when a β-amylase treatment was applied to acetylated and debranched potato starch. The degree of acetylation was generally higher in the soluble complexes than in the insoluble ones. The insoluble complexes from the acetylated starch displayed the V-type pattern, whereas, the soluble complexes displayed a mixture of either the A-/V-type or the B-/V-type pattern. Acetylation decreased onset and peak melting temperatures for the insoluble complexes, whereas no melting endotherm was observed in the soluble complexes. Acetylation substantially increased the amount of complexed linoleic acid in the insoluble complexes, but had little positive effect on the formation of the soluble complexes. The β-amylase treatment significantly increased the complexed linoleic content in both soluble and insoluble complexes for the low acetylated starch, but not for the high acetylated starch.

In-vitro digestibility, rheology, structure, and functionality of RS3 from oat starch

Starches isolated from three different varieties of oat were modified with dual autoclaving-retrogradation treatment to make modified food starches with high contents of type 3 resistant starch (RS3). FT-IR spectroscopy showed increase in the ratio of intensity of 1047cm−1/1022cm−1 on treatment. Morphology of the oat starches changed into a continuous network with increased values for onset temperature (To), peak temperature (Tp), and conclusion temperature (Tc). XRD showed an additional peak at 13° and increase in peak intensity at 20° inclusive of the major X-ray diffraction peaks which reflects formation of amylose–lipid complex from dual autoclaving-retrogradation cycle. Peaks at 13° and 20° are the typical peaks of the V-type pattern. Rheological analysis suggested that retrogradated oat starches showed shear thickening behavior as revealed from Herschel-Bulkely model and frequency sweep.

Preparation and characterization of acetylated starch nanoparticles as drug carrier: Ciprofloxacin as a model

The objective of this study was to characterize in-vitro the potential of acetylated corn starch (ACS) particles as a matrix for the delivery of ciprofloxacin (CFx). ACS was successfully synthesized and optimized by the reaction of native corn starch using acetic anhydride and acetic acid with low and high degrees of substitution (DS). The nanoprecipitation method was applied for the formation of the ACS-based nanoparticles, by the dropwise addition of water to acetone solution of ACS under stirring. The effects of acetylation and nanoprecipitation on the morphology and granular structure of ACS samples were examined by the FT-IR, XRD, DSL and SEM techniques. The efficiency of CFx loading was also evaluated via encapsulation efficiency (EE) in ACS nanoparticles. The average degree of acetyl substitution per glucose residue of corn starch was 0.33, 2.00, and 2.66. The nanoparticles size of the ACS and ACS-loaded with CFx were measured and analyzed relative to the solvent:non-solvent ratio. Based on the results, ACS nanoparticles with DS of 2.00 and water:acetone of 3:1 had 312nm diameter. Increasing DS in starch acetate led to increase in the EE from 67.7 to 89.1% and with increasing ratio of water/acetone from 1:1 to 3:1, the EE raised from 48.5 to 89.1%. X-ray diffraction indicated that A-type pattern of native starch was completely transformed into the V-type pattern of acetylated starch. The scanning electron microscopy showed that the different sizes of pores formed on the acetylated starch granules were utterly converted into the uniform-sized spherical nanoparticles after the nanoprecipitation.

Studies on the Physicochemical Properties of the Developed Instant Tomato and Lemon Rice

“Instant rice, also known as minute rice, is rice that has been precooked and dehydrated so that it cooks more rapidly” (within 10 min). The process of producing instant rice involves cooking of rice, freezing, freeze drying to required moisture content and storage in polyethylene pouches. Rice was cooked in three different, rice to water ratios (1: 2, 1: 3, and 1: 4). The cooked rice were used to prepare two types of instant rice varieties (tomato rice and lemon rice). Proximate composition analysis, moisture content, density, rehydration ratio, swelling capacity, moisture sorption, free fatty acid content, X-Ray diffraction and scanning electron microscopy analysis were performed. The final product was also subjected to sensory analysis. The densities of lemon rice and tomato rice were found to be 0.236 g/cm3 and 0.244 g/cm3, respectively. The swelling capacities of lemon rice and tomato rice were found to be 0.0254 ml/seed and 0.0263 ml/seed, respectively. The rehydration process was standardized to be 1: 2.25 rice to water ratio for 3min. The instant rice samples showed the presence of V-type pattern revealing the formation of amylase-lipid complexes in X-Ray Diffraction. Keywords: Instant rice, freeze drying, properties, rehydration, quality analysis.

Effect of banana peel powder on bioactive constituents and microstructural quality of chapatti: unleavened Indian flat bread

Effect of banana peel powder (BPP) on the bioactive constituents and micro structural quality of cha- patti was evaluated. Chapatti dough prepared from 5, 10, 15 and 20 % BPP was examined for dough stickiness, dough strength, dough kneading and rollability. With increased level of BPP, there was an increase in subjective score in kneading and rollability of chapatti. Dough stickiness was increased while increased dough strength was observed with increased level of BPP. Chapatti incorporated with BPP showed total phenolic content and flavonoid content significantly higher than the control. Chapatti incorporated with 20 % BPP showed DPPH rad- ical scavenging activity up to 68.3 %. The tear force of chapatti prepared from dough added with 5, 10, 15 and 20 % BPP was 414, 404, 393, 356.2 g which was lower than that of control (449 g). The microstructure of chapatti prepared from dough added with 15 % BPP was uniform with solubilised starch granules while in the control starch granules were overlapping on one another to form aggre- gation. The X-ray diffraction pattern for chapatti incorpo- rated with 15 % BPP showed V-type pattern. Chapatti's prepared from BPP had softer chapatti and better pliability.

The effect of different nixtamalisation processes on some physicochemical properties, nutritional composition and glycemic index

The objective was to evaluate corn tortillas made from three nixtamalisation processes including Traditional with lime (TNP), Classic with ashes (CNP) and Ecological with Ca salts (ENP), and their effect on mineral content (Ca, Fe, K, and Mg), chemical composition, resistant starch (RS), and glycemic index (GI). ENP with calcium propionate and carbonate had higher fat values than tortillas from CNP. EPN and CNP presented the higher dietary fibre, explained by the highest pericarp retention. In TNP the pericarp and external layers were lost during the cooking, steeping and washing steps and had lower crude fiber. The amount of RS increased in nixtamal and tortillas independently of nixtmalisation processes. Annealing of starch was shown by the increase of onset, peak and final gelatinisation temperatures in nixtamalised products compared with untreated maize. Gelatinisation was higher for calcium propionate ENP and 1% ash CNP. Native maize changed from A-type to V-type pattern in nixtamalised products denoting the formation of amylose-lipid complexes. Overall, nixtamalisation processes and salts used increased RS. The GI was affected by chemical composition in tortillas and amount of RS. Tortillas made from ENP Ca propionate and ENP 1% ash CNP can be classified as low GI foods.

Structure and digestibility of debranched and repeatedly crystallized waxy rice starch

Debranched waxy rice starch was subjected to repeated crystallization (RC) treatment, and its physicochemical properties and digestion pattern were investigated. The A-type crystalline pattern of native starch was crystallized to a complex of B- and V-type patterns by debranching and RC treatment. Among the treated starches, the relative crystallinity of debranched starch reached its maximum (29.6%) after eight repetitions of crystallization. Changes in weight-average molar mass among treated starch samples were not significantly different. The repeated-crystallized starches showed higher thermal transition temperatures and melting enthalpy than that of debranched starch. As a result, slowly digestible starch (SDS) content of repeated-crystallized starches reached a very high level (57.8%). Results showed that RC treatment induced structural changes of waxy rice starch result in a great amount of SDS.

Effect of puffing on physical and antioxidant properties of brown rice

The objective of this study was to investigate the effect of puffing process on the physical, antioxidant properties and mineral composition of brown rice. Bulk density significantly varied (P<0.05) among the puffing stages and was lowest in expanded rice. From Hunter colour analysis, the lowest L∗ value and highest a∗ and b∗ values were observed for parboiled rice (P<0.05). A-type of diffraction pattern, observed in raw rice was altered by puffing process and led to the formation of B- and V-type patterns. Raman spectrum showed the intense peaks in raw rice and the intensity of those peaks was decreased during the puffing process. Scanning electron microscopy revealed a highly porous structure of expanded rice kernel. Significant decrease in the antioxidant properties was observed upon puffing process as compared to raw rice samples. Hence the present study demonstrates that the puffing process leads to the significant changes in the properties of brown rice.

Frequency splitting patterns in wireless power relay transfer

Frequency splitting patterns in low-order wireless power relay transfer systems are analysed by the coupled-mode theory. In addition to the V-type splitting pattern reported widely, two new patterns, I-type and W-type, are introduced. Specifically, it is found that a 0-relay system shows a V-type or I-type splitting; a symmetrical 1-relay system shows an I-type or W-type splitting; and a symmetrical 2-relay system usually shows a V-type or W-type splitting. The criteria for different frequency splitting patterns are given, and the theoretical results are validated finally by 1-relay and 2-relay wireless power transfer experimental systems.

Threshold tool-radius condition maximizing the formability in SPIF considering a variety of materials: Experimental and FE investigations

In the current study, a new level of understanding on the influence of using small tool radii on the formability (θmax) is identified for single point incremental forming (SPIF). The relative value of tool radius and blank thickness (i.e., R/TB, where R is the tool radius and TB is the blank thickness) was varied over a range (from 1.1 to 3.9), and a formability diagram in the R/TB–θmax space was obtained. The formability was observed to show an inverse V-type pattern which revealed that there is a critical radius of tool (Rc) that maximizes the formability in SPIF. Further, this radius which was found to be independent of the material type (or property) is a function of blank thickness related as, Rc≈2.2TB. This radius was termed as threshold radius. The formability, in agreement with general opinion in the literature, was noticed to increase with the decrease in the tool radius above the threshold value. However, contrarily it reduced with the decrease in the tool radius below the threshold value. In fact, undue surface cutting and metal squeezing was detected when the tests were performed with pointed tools, i.e., below threshold radius. This unstable deformation, which according to the FE analyses was found to be an outgrowth of in-plane compression under the tool center, increasingly weakened the material by inducing corresponding increase in damage (quantified by stress triaxiality) with the decrease in the tool radius. On the other hand, the damage was also observed to increase due to decrease in compression with the increase in the tool radius above the threshold value. This revealed high compression with low damage constitutes the most conducive condition that maximizes the formability in SPIF, which is realized when R≈2.2TB.

Effects of heat treatment and moisture contents on interactions between lauric acid and starch granules.

This study aimed to understand the effects of the moisture content of granular normal cornstarch (NC), heat treatment at 80 °C, and order of adding lauric acid (LA) to starch before or after the heat treatment on the physicochemical properties and digestibility of the starch. LA was added to NC priority heated with different moisture contents (10, 20, 30, 40, and 50%) or added to dried NC and then heated with different moisture contents. The hydrothermal/LA treatments increased the pasting temperature but decreased the peak viscosity of the NC. Light and scanning electron microscopy revealed that the addition of LA retarded gelatinization. The hydrothermal/LA treatments changed the X-ray pattern of the NC to a mixture of A- and V-type patterns. The thermal property and digestibility analysis showed that 40% was the optimum moisture content for the formation of the amylose-LA complex and adding LA prior to heating the NC favored the formation of slowly digestible starch.

Physical properties and loading capacity of gelatinized granular starches

The gelatinized granular starches (GGSs) were prepared by treating granules with aqueous ethanol. The prepared GGSs were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) technique. SEM pictures of the GGSs treated ethanol at controlled temperatures (80, 85, and 88°C) showed porous and wrinkled surface. A-type diffraction reflections were completely lost with evolution of V-type patterns of these samples, and their swelling power was increased with increasing temperature. In addition, drug loading capacity was investigated with tea polyphenols (TP) as a model drug on the basis of single-factor study. It was found that the loading amount of TP was significantly influenced by loading time, loading temperature as well as TP concentration (P<0.05). Either the increase of loading time or drug concentration could lead to the increase of drug loading amount of GGSs, however, drug loading amount reached its maximum in aqueous medium at room temperature.

Fabrication and Characterization of Size-Controlled Starch-Based Nanoparticles as Hydrophobic Drug Carriers

Acetylated corn starch was successfully synthesized and optimized by the reaction of native corn starch with acetic anhydride and acetic acid in the presence of sulfuric acid as a catalyst. The optimal degree of substitution of 2.85 was obtained. Starch-based nanoparticles were fabricated by a simple and novel nanoprecipitation procedure, by the dropwise addition of water to acetone solution of acetylated starch under stirring. Fourier transform infrared spectrometry showed that acetylated starch had some new bands at 1750, 1375 and 1240 cm(-1) while acetylated starch nanoparticles presented the identical peaks as the drug-loaded acetylated starch nanoparticles and the acetylated starch. Wide angle X-ray diffraction indicated that A-type pattern of native starch was completely transformed into the V-type pattern of Acetylated starch and starch-based nanoparticles show the similar type pattern with the acetylated starch. The scanning electron microscopy showed that the different sizes of pores formed on the acetylated starch granules were utterly converted into the uniform-sized spherical nanoparticles after the nanoprecipitation. The encapsulation efficiency and diameter of nanoparticle can be adjusted by the degree of substitution, the volume ratio of nonsolvent to solvent and the weight ratio of acetylated starch to drug. It was also depicted that the release behaviors of drug-loaded nanoparticles depend on the size of nanoparticles and the degree of substitution of the acetylated starch. Release studies prove that the starch-based nanoparticles with uniform size can be used for the encapsulation of hydrophobic drug and attained the sustained and controllable drug release carriers.

Laboratory Process Development and Physicochemical Characterization of a Low Amylose and Hydrothermally Treated Ready-to-Eat Rice Product Requiring No Cooking

A low amylose and hydrothermally treated ready-to-eat rice product that requires no cooking was prepared in the laboratory. Hot soaking for 1–3 min with subsequent variable steaming at open and under pressures remarkably altered the kernel and flour properties. Increase in water absorption and lowering of cooking time with extent of steaming were prominent. Soaking of the product at 50 °C for 20 min gave texture values more similar to cooked samples. The viscosity parameters of hot soaking alone were in between those of hot soaking with open steaming and pressure steaming. Pressure steamed samples exhibited almost constantly increasing slurry viscosity throughout the heating and cooling phases of the rapid viscosity analyzer profile. Steaming variably altered the native A-type X-ray diffraction pattern. Pressure steaming of samples with 3 min hot soaking caused complete loss of the A-type conformation with feeble peaks for B- and V-type patterns. The open steamed samples showed peaks for all A-, B-, and V-type patterns. No endotherms for amylose-lipid complexes were however found in the differential scanning calorimetry of the pressure steamed samples. The raw rice flour was highly resistant to α-amylolysis. In open steamed samples, steaming severity decreased the hydrolysis rate indicating formation of enzyme-resistant fractions, while pressure steamed samples showed higher digestibility with treatment severity.

Preparation and characterization of gelatinized granular starches from aqueous ethanol treatments

In order to modify the properties of native starch granules, the formation of gelatinized granular forms (GGS) from normal, waxy, and high amylose maize, as well as potato and tapioca starches was investigated by treating granules with aqueous ethanol at varying starch:water:ethanol ratios and then heating in a rotary evaporator to remove ethanol. The modified starches were characterized using bright field, polarized and electron microscopy. Short/long range molecular order and enthalpic transitions on heating were also studied using infrared spectroscopy, X-ray diffractometry and differential scanning calorimetry respectively. A diffuse birefringence pattern without Maltese cross was observed for most GGS samples. Treatment with aqueous ethanol resulted in starch-specific changes in the surface of granules, most noticeably swelling and disintegration in waxy maize, surface wrinkling in normal maize and tapioca, swelling and opening-up in potato starches, and swelling and bursting in high amylose maize. The ratio of ethanol to water at which original granular order was disrupted also varied with starch type. GGS had less short range molecular order than native granules as inferred by comparing 1047/1022 wave number ratio from infrared spectroscopy. Similarly, A- and B-type diffraction reflections were either reduced or completely lost with evolution of V-type patterns in GGS.

Effect of processing on the microstructure of finger millet by X-ray diffraction and scanning electron microscopy

Finger millet is one of the important minor cereals, and carbohydrates form its major chemical constituent. Recently, the millet is processed to prepare hydrothermally treated (HM), decorticated (DM), expanded (EM) and popped (PM) products. The present research aims to study the changes in the microstructure of carbohydrates using X-ray diffraction and scanning electron microscopy. Processing the millet brought in significant changes in the carbohydrates. The native millet exhibited A-type pattern of X-ray diffraction with major peaks at 2θ values of 15.3, 17.86 and 23.15°, whereas, all other products showed V-type pattern with single major peak at 2θ values ranging from 19.39 to 19.81°. The corresponding lattice spacing and the number of unit cells in a particular direction of reflection also reduced revealing that crystallinity of starch has been decreased depending upon the processing conditions. Scanning electron microscopic studies also revealed that the orderly pattern of starch granules changed into a coherent mass due to hydrothermal treatment, while high temperature short time treatment rendered a honey-comb like structure to the product. However, the total carbohydrates and non-starch polysaccharide contents almost remained the same in all the products except for DM and EM, but the individual carbohydrate components changed significantly depending on the type of processing.

Physicochemical property changes in wheat starch by ultra-fine pulverization

This study was performed to analyze the effects of ultra-fine pulverization (UFP) on the physicochemical properties of wheat starch (WS) using a high impact planetary mill. The average diameter and specific surface area of the WS was decreased from 15.15 to 9.10 μm and from 1.043 to 1.994 m2/g, respectively, throughout UFP. UFP significantly increased damaged starch content from 17.5 to 83.7%. The pulverized wheat starch (PWS) had higher swelling power, solubility, and transmittance values than WS between a temperature range of 50 and 90°C. X-Ray diffractograms revealed WS had an A-type pattern, which disappeared in PWS which showed a broad V-type pattern. The rapid visco analyzer (RVA) characteristics, peak viscosity, break down, and set back of WS were absent in PWS and flattened viscosity was shown. In differential scanning calorimetry (DSC) curves, peak temperature (Tp), and gelatinization enthalpy (ΔE) were decreased in PWS compared to WS. The enzymatic (α-amylase) digestibilities of WC and PWS were 67.4 and 75.2%, respectively.