Starch Size Research Articles

Effects of water restriction on carbohydrates concentration, starch granules size and amylolytic activity in seeds of Phaseolus vulgaris L. and P. acutifolius A. Gray

Background: Seed mass is a key component of adaptation in plants that are strongly affected by development and maturity, and, at the same time, all is modulated by the environment of cultivation.
 Hypotheses: The response to water deficit in seeds of P. vulgaris L. and P. acutifolius A. Gray is species-dependent and affects their biochemical and morphological characteristics.
 Studied species: The studied cultivars were Rosa Bufa ( P. vulgaris ) and cv. 10017 ( P . acutifolius ). Seeds were obtained from plants grown at 100 % and 25 % soil field capacity during their pod development. 
 Study site and dates: The experiments were performed during May and August 2018 in a greenhouse at the Colegio de Postgraduados, Texcoco, State of Mexico (altitude 2,353 m).
 Methods: The biochemical and morphological characteristics and the grain size of starch in seeds cotyledons were assessed.
 Results: Water restriction had no significant effects on the seed thickness, width, or mass only length decreased in P. acutifolius . In both species, the axis size of the starch granules decreased due to the stress, glucose concentration increased, sucrose and starch were not altered. Water imbibition increased six times in P. vulgaris seeds with no effect on the germination. The α-amylase activity was 25 - 35 % lower in both species due to the water restriction, particularly in P. acutifolius the activity was two-fold higher than in P. vulgaris .
 Conclusions: Comparing the carbohydrate concentration in germinating seeds of common and Tepary beans gave insights on the nutrient reserves mobilization during seed maturation and germination.

Effect of selected physical and chemical modifications on physicochemical, pasting, and morphological properties of underutilized starch from rice bean (Vigna umbellata).

Starch was extracted from the rice bean which is largely underutilized and modified by physical (i.e. heat moisture treatment and retrogradation) and chemical (i.e. esterification and acid alcohol modification) methods. Both, physical and chemical modifications significantly (p < 0.05) affected the physicochemical, pasting, particle size and morphological properties of rice bean starch. Both amylose content and swelling power reduced after physical and chemical modifications. Among modified starches, retrograded starch showed higher solubility (8.56%) at 90°C. Retrogradation also resulted in higher values of water (251%) and oil absorption (106%) capacities in comparison to other modified starches. Physical modifications greatly influenced the pasting properties in comparison to chemical modifications. The particle size distribution followed the order: native starch (659.8nm) > heat moisture treated (434.3nm) > retrograded (355.4nm) > esterified (218nm) > acid alcohol treated starch (234.5nm). The study revealed that the particle size of rice bean starch was reduced by both physical and chemical modifications. FE-Scanning electron microscopy was used to study the morphological characteristics of starches and it was observed that retrogradation had a pronounced effect on the starch granules morphology.

Experimental and Numerical Simulation of Starch Degradation under Sonication Process

Starch processing technology has been developed to enlarge the application of starch in most of food, medical and fermentation industries. Sonication is prominent technology that can alter physical and molecular structure of many material by generating vigorous cavitation which gives radicals and a microjet. Many researches of starch sonication process has been carried out experimentally, but there is only very small number of published works that correlated the experiment data and suitable reaction model. In this study, a reaction model that correlates with experimental results was develop to predict molecular weight, granule size, and conversion of cassava starch. The sonication has simulated with the nth-order reaction model. The result show the reaction was controlled by physical process control. The simulation depict that sonication process can produce a lower molecular weight of starch in very short time. At later time process, the sonication degradation ability was reduced because some part of granule have ability to withstand the cavitation.

Changes in molecular size and shape of waxy maize starch during dextrinization

The conformational properties of pyrodextrins from waxy maize starch were investigated by high performance size exclusion chromatography with multiple detectors, and the relationships (Mark-Houwink equations) between molecular weights and intrinsic viscosities of pyrodextrins in water were established. Pyrodextrin was prepared by adjusting waxy maize starch to pH 3 or 2, heating at 170 °C or 150 °C. As heating time increased from 0.5 to 4 h, the molecular size was decreased in the order of pH 2 and 150 °C > pH 3 and 170 °C > pH 3 and 150 °C. The measured exponent α values in Mark-Houwink equation indicated that the pyrodextrins prepared at pH 3, 170 °C and 150 °C only had one compact spherical conformation (α 0.27–0.31) during dextrinization, whereas the pyrodextrins prepared at pH 2 and 150 °C had a mixture of two shapes of molecules: compact sphere (α 0.26) and rigid coil (α 0.89) conformation.

Effects of the degree of milling on starch leaching characteristics and its relation to rice stickiness

Rice milling is a very common process to improve rice edible quality. In this study, the effects of the degree of milling (DOM) on starch leaching characteristics and its relation to rice stickiness were investigated. As DOM increased, the whiteness of rice grains and rice stickiness increase, while the protein and lipid content of rice grains decreases. By examining the starch leaching characteristics during rice cooking, it shows that i) increasing DOM significantly increases the total solids and leached starch content while decreases the leached protein content; ii) the molecular size and chain-length distribution (CLD) of leached starch are not significantly varied between rice samples with different DOM, but are significantly different from that of native starch; iii) a significant correlation between rice stickiness and leached amylopectin amount is established; iv) the molecular mechanism for the increased stickiness as affected by DOM is also proposed. The improved understanding of rice processing obtained in this study may allow a better control of rice eating quality.

Granule size distribution and pasting properties of starch in normal, waxy and sweet maize kernels

The granule size and pasting properties of starch and their relationship with quality of maize (Zea mays L.) was investigated. A clear bimodal distribution of granule sizes was found in six cultivars of maize. A number of starch granules were made up of small starch granules in kernels. Normal maize had a smaller proportion of granules &lt;12 μm and a greater proportion of granules &gt;12 μm, whereas sweet maize had a greater proportion of granules &lt;12 μm and a smaller proportion of granules &gt;12 μm. The peak, trough and breakdown viscosities were found higher in waxy maize and lower in sweet maize. The final and setback viscosities were found higher in normal maize and lower in sweet maize. The peak, trough, final and setback viscosities were significantly and negatively correlated to volume percentage of granules &lt;12 μm and significantly positively correlated with the volume percentage of granules &gt;12 μm.

Mechanical, SEM and FTIR characteristics of bioplastics from mango seed starch with nanoparticle zinc oxide as filler and ethylene glycol as plasticizers

Plastic products are difficult to be degraded and cause environmental problem. To overcome this, plastic material is made from biodegradable natural resource which is called bioplastics. The aim of this research is to know the potency of mango seed starch, nanoparticle zinc oxide as filler and ethylene glycol as plasticizer. The mango seed starch size of 5 grams, with variation of zinc oxide filler mass of 0; 3; 6 and 9% (wt) and ethylene glycol 0; 20; 25; 30 and 35% (wt). The bioplastics films was analyzed the mechanical properties include tensile strength, elongation at break, SEM and FTIR. The optimum result obtained at nanoparticle ZnO concentration 6% and ethylene glycol 25% with tensile strength 3.78 MPa and elongation at break 2.23%. The SEM and FTIR result prove that addition of filler and plasticizer gives better surface morphology and dispersion in the bioplastics.

Starch gelatinization in the surface layer of rice grains is crucial in reducing the stickiness of parboiled rice

Parboiled rice has high nutritional value but unpleasant palatability. In this study, rice stickiness was significantly reduced by steaming during the parboiling process; however, continuing steaming past certain durations no longer affected rice stickiness. It was also found: (i) the degree of starch gelatinization (DSG) increases and starch crystallinity decreases with increasing steaming time; (ii) the molecular size and chain length distribution (CLD) of leached starch for both white and parboiled rice are significantly different from those of native starch; (iii) the relation between leached amylopectin amount and rice stickiness explains the reduced stickiness by parboiling; and (iv) starch gelatinization in the surface layer of rice grains during parboiling might be critically important in blocking starch leaching, consequently leading to a less sticky texture. This study supplies a way to manage glutinous rice stickiness by parboiling for the production of non-sticky rice foods.

Effects of nitrogen level on structural and functional properties of starches from different colored-fleshed root tubers of sweet potato

The nitrogen (N) influences the growth of sweet potato. However, it is unclear whether the different levels of N can affect starch physicochemical properties. In this study, 9 different colored-fleshed sweet potato varieties were planted in the same field with additional N fertilizer treatment of 0, 15 and 30 kg/ha. The physicochemical properties of starches from root tubers were measured. With increasing N level, the amylose content decreased in yellow-fleshed variety Sushu 16 and increased in white-fleshed variety Sushu 29 and purple-fleshed varieties Ningzishu 1 and 4, but did not significantly change in other varieties. The starch size decreased in purple-fleshed variety Ningzishu 1 and white-fleshed varieties Sushu 28 and Sushu 29 with increasing N treatment, but first increased then decreased in yellow-fleshed variety Sushu 16 and first decreased then increased in white-fleshed variety Sushu 24 and yellow-fleshed variety Sushu 25. The different levels of N treatment had no influence on protein content, crystalline structure, and gelatinization enthalpy of starch. The effects of N treatment on gelatinization temperatures and pasting viscosities of starches were determined by varieties and genotype backgrounds of sweet potato. The PLSR and PLS-DA were also carried out based on structural, thermal, and pasting parameters of starches.

Synthesis and characterization of nano starch-based composite films from kidney bean (Phaseolus vulgaris).

This study was aimed to synthesize and evaluate the nano starch-based composite films by the addition of nano starch in film formulation at 0.5, 1, 2, 5 and 10% level of total starch. The acid hydrolysis technique was used to reduce the size of starch granules of kidney bean starch. The physicochemical properties of both native and nano starch were determined. Nano starch showed a higher value for swelling power, solubility, water and oil absorption capacity when compared with native starch. The particle size of kidney bean nano starch was 257.7nm at 100% intensity. The size of starch granule affects various properties of films. The thickness, solubility and burst strength of the composite films were increased significantly (p ≤ 0.05) with an increase in the concentration of nano starch in film formulation. While the moisture content and water vapour transmission rate (WVTR) were decreased significantly (p ≤ 0.05) with an increase in the concentration of nano starch in film formulation. The results suggested that kidney bean starch could be used for the development of packaging films. The utilization of nano starch in film formulations had an additional advantage in improving the film properties.

Oxidation of cassava starch at different dissolved ozone concentration: effect on functional and structural properties

An environmentally friendly method for starch oxidation is recommended in order to replace harmful oxidizing chemical reagents. Ozone is an environmentally friendly oxidizing reagent that leaves no residue in the final product. Studies of starch modification using dissolved ozone are still lacking. This work aimed to increase the use value and improve native starch characteristics by evaluating carbonyl and carboxyl contents, pasting and functional properties, spectral Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) profiles, particle sizes, and scanning electron micrographs (SEM) of ozone-oxidized cassava starch. The results showed that dissolved ozone and starch slurry concentrations significantly affected oxidation degree, functional properties and caused a decrease in particle size and pasta viscosity of cassava starch. FTIR spectra significantly showed an increase in the intensity of the presence of the carbonyl group as a marker of starch oxidation. Further XRD diffraction also significantly showed changes in the relative crystallinity besides that there is a change in the surface morphology of the starch granules. Oxidized starch with a combination of 1.4 ppm dissolved ozone concentration and a starch slurry ratio of 1:10 produced higher swelling power (44.31%), solubility (0.88%), lower paste viscosity (6082.5 cP), and reconditioning relative crystallinity (10.44%). Overall, dissolved ozone successfully had powerful effects in oxidizing starch and can be applied for starch modification as an inexpensive and safe oxidizing agent.

High-pressure homogenization thinned starch paste and its application in improving the stickiness of cooked non-glutinous rice

Improving the stickiness of non-glutinous rice is an important strategy in scaling out the applications of rice foods, e.g. Sushi, Zongzi etc. In this study, the effect of HPH treatments on the transparency and molecular structure of starch and the stickiness of cooked non-glutinous rice were investigated by cooking rice with high-pressure homogenization (HPH) thinned starch paste. HPH treatments significantly increased the light transmittance of starch paste from 7.6% to 81.3% (p < 0.05). The average molecular size of corn starch is reduced with HPH pressure increasing while HPH treatment significantly decreases the content of starch chains with degree of polymerization (DP) 37–100 and DP 2000–20000 (p < 0.05). By cooking rice with the HPH treated starch paste solutions, the stickiness of non-glutinous rice is significantly increased (p < 0.05) and the HPH treatment with 60 MPa and 3% starch concentration is the optimal condition in increasing rice stickiness. This study paves a way in improving the stickiness of non-glutinous and a great potential in amplifying the applications of rice products by modifying rice stickiness attribute.

Changes in particle size, structure, and physicochemical properties of potato starch after jet‐milling treatments

Changes in particle size, structure, and physicochemical properties of potato starch after jet‐milling treatments

Characterisation of Starch from Selected Curcuma Species of Kerala through Microscopy and CHNS Analysis

Starch isolated from different plant sources are regarded as vital in food industry, where the granule size and shape determine its function and uses. Native starches irrespective of their sources are not desirable for many applications. Many Indian tribals explored certain Curcuma species as source for starch and prepare various food items, mainly considering its medicinal importance. Presently, a range of highly priced starch powders are available in the market in the label of herbal nutraceuticals. Starch from the rhizomes of eight different native Curcuma species of Kerala and Maranta arundinacea (Arrow root) were extracted, characterised and compared. It was found that size, shape and CHNS data of starch is varying and could be useful in taxonomic identification of the species. The species specific features of the starch granules would also be useful to find its adulterants. The study also points out its edible value.

Structure and properties of soft rice starch

Pasting and rheological properties of starch from soft rice and two traditional rice varieties were analyzed. Soft rice starch was found to have a low pasting temperature of 67.2 °C, with a high system viscosity, including peak and trough viscosity. The storage modulus and loss modulus of soft rice starch were high and showed good viscoelasticity. The amylose content of soft rice starch was found to be 11.3%, classifying it was low amylose content type. Compared with japonica rice starch, soft rice starch had lower solubility but higher swelling power, gel consistency, and water binding capacity. The medium particle size and volume mean particle size of soft rice starch were the highest. The average molecular weight of soft rice starch was 5.4 × 107. The molecular density and proportion of short amylopectin side chains, with a range of 6–12, were the highest among all varieties tested. These findings provide a theoretical basis for the processing of soft rice starch and breeding of high-quality rice.

Evaluation of the source breeding material of winter triticale by the main signs of suitability for processing into bioethanol

Purpose . To analyze collection samples by yield, protein and starch content in grain, its granulometric composition and highlight valuable sources for creating varieties sui­table for bioethanol processing. Methods. To assess the collection material, field, laboratory, measurement and weight, mathematical and statistical research methods were used. The analysis of chemical quality indicators of triticale grain was carried out by infrared spectrometry on an Infratec 1241 device. The size of starch granules was determined by light microscopy and using the ImageJ computer program. Statistical processing of the obtained research results was carried out with the introduction of the computer program Statistica 6. Results. The results of studies on the collection of winter triticale by the main signs of suitability for bioethanol processing are presented. The grain yield in collection samples on average over the years of research ranged from 3.69 to 5.17 t/ha. The best samples were identified – numbers 181, 101, 185, 219 and the variety ’Arystokrat’ with a yield of 5.01–5.17 t/ha. By the high starch content numbers 123 (69.5%), 101 (69.8%) and the varieties ‘Petrol’ (69.0%), ‘Solodiuk’ (70.1%) and ‘Liubomyr’ (70.3%) were selected. A moderate negative correlation was found between yield and protein content (r = -0.37) and a significant negative correlation was found between starch and protein content (r = -0.64). The analysis of collection samples of winter triticale by granulometric starch composition was carried out. Maximum size of starch granules in the collection samples ranged from 19.4 to 32.7 µm, the minimum – 9.9 to 15.7 µm, and the variability range for the average size of granules was 15.4–20.0 µm. Varieties ‘Yasha’ and ‘Mundo’ were distinguished by the smal­lest average granule size of starch (15.4 and 15.6 µm) and uniformity of particle size distribution. Conclusions . Sources of valuable traits were identified by high productivity, starch content and aligned and fine granule size distribution. A moderate correlation between productivity and protein content and a significant negative correlation between starch and protein content was revealed.

Effect of Mesona chinensis polysaccharide on the pasting, rheological, and structural properties of tapioca starch varying in gelatinization temperatures

The effects of Mesona chinensis polysaccharide (MCP) on the pasting, rheological properties, granule size, and water mobility of tapioca starch (TS) were investigated at different gelatinization temperatures (75 °C and 95 °C). The structures of tapioca starch-Mesona chinensis polysaccharide (TM) gels formed at different gelatinization temperatures were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results showed that the peak, trough, and final viscosities of TM-95 mixtures were lower than that of TM-75 mixtures. Addition of MCP had a significant reduce (p < 0.05) on the granule size and transversal relaxation time of TM mixtures at the two gelatinization temperatures. Rheological analysis also showed that the addition of MCP increased the consistency indexes (K) and decreased the flow behavior indexes (n) of TM-95 and TM-75 gels. XRD results confirmed the diffraction peak of TM-95 gels became blunt and wider, and the diffraction peak at 17° and 23° of TM-75 gels could be observed after MCP added. In addition, the microstructures of TM-75 gels were more compact than that of TM-95 gels. These results can promote the development of TS-based products and application of MCP at different gelatinization temperatures.

Effects of oligosaccharides on particle structure, pasting and thermal properties of wheat starch granules under different freezing temperatures

The effects of fructooligosaccharides (FOS), galactooligosaccharides (GOS), and xylooligosaccharides (XOS) on gelatinization, retrogradation, thermal properties and particle size of wheat starch at different freezing temperatures were studied. The results showed that the wheat starch porosity, particle size, peak viscosity increased with increasing freezing temperature. With the addition of 16% oligosaccharides to starch, the porosity, particle size, crystallinity, initial gelatinization temperature, peak value, breakdown and retrogradation viscosity of the starch granules significantly decreased in the order of XOS > GOS > FOS. However, the pasting temperature of the granules increased. The addition of oligosaccharides (especially XOS, which has the most significant effect in inhibiting starch retrogradation) can inhibit the formation of starch crystal structures to a certain extent, reduce the damage from ice crystals to starch granules and delay starch retrogradation. Therefore, functional oligosaccharides can be used as a potentially effective additive to increase freezing stability in frozen starch-based foods.

Effects of Extrusion Technology Combined with Enzymatic Hydrolysis on the Structural and Physicochemical Properties of Porous Corn Starch

Effects of the combination of extrusion pretreatment and enzymatic hydrolysis on corn starch are investigated through its microstructural and physicochemical properties. This combined modification resulted in the formation of more pores on the surface of native starches (NS), as revealed by scanning electron microscopy (SEM). Compared with either single-treatment modified starch samples, starch that was bioextruded and treated by enzymatic hydrolysis achieved higher crystallinity, more uniform pore structure, and higher gelatinization temperature than those of native porous starch, as determined by X-ray diffraction (XRD), Fourier-transform infrared (FTIR), and differential scanning calorimetry (DSC). Low-temperature nitrogen adsorption experiments showed that the specific surface area (2.52 m2/g), total pore volume (4.53 × 10−3 cm3/g), and average pore size (7.36 nm) of porous starch were significantly increased by bioextrusion combined with enzyme hydrolysis (P < 0.05). The results of hydrolysis degree (DH) also showed that bioextrusion could improve the efficiency of hydrolysis. Starch that was bioextruded followed by enzyme hydrolysis showed the highest adsorption capacity in adsorption tests of adsorption of oil (63.29%), water (162.61%), and methylene blue (6.04%). The present study suggests that the combination of bioextrusion pretreatment and enzymatic hydrolysis is an attractive alternative for preparing porous corn starches.

Comparison of physicochemical properties of oca (Oxalis tuberosa), potato, and maize starches

Oca (Oxalis tuberosa) represents a novel source of starch. Starches from the tubers of two commercial oca varieties were studied for various physicochemical properties. One normal potato starch and one normal maize starch were used for comparison. Oca starches showed lower gelatinization temperatures compared to both potato and maize starches. The pasting, flow, and gelation behaviors of oca starches were intermediate between potato and maize starches. Oca starch pastes were more viscous than maize starch paste and more elastic than potato starch paste. The differences in the properties could be largely due to lower amylose content, intermediate contents of phosphate groups (~400 ppm) and granule size (34.6 μm) of oca starches as compared to the other two starches. The internal unit chains of amylopectin such as the amount of fingerprint B-chains and length of B-chains could also partially explain the different physicochemical properties among oca, potato and maize starches.