共查询到20条相似文献,搜索用时 24 毫秒
1.
Alberto E. León Gabriela N. Barrera Gabriela T. Pérez Pablo D. Ribotta Cristina M. Rosell 《European Food Research and Technology》2006,224(2):187-192
The effect of the amount of damaged starch in two different flours (wheat and triticale) on the bread quality and its behaviour during storage has been analysed. Two wheat and one triticale flour cultivars were milled in a disc mill to obtain different levels of damaged starch. Differential Scanning Calorimetry (DSC) and Rapid Visco Analyser (RVA) were used to characterize the flour properties and TA-XT2 textural analyses were made on breadcrumb. The effect of the damaged starch content on the bread firming, the amylopectin retrogradation and starch-pasting properties were studied in order to establish any relationship between damaged starch and bread staling. DSC analysis showed that the damaged starch content changed the thermal behaviour of flour–water mixtures: the higher the levels of damaged starch the lower the starch-gelatinization enthalpy and the higher the melting enthalpy of amylose–lipid complexes. The amount of amylopectin retrogradation and breadcrumb firming increased with the damaged starch content at the beginning of storage time; however, differences were decreasing at final storage time. The flour viscosity during pasting decreased as their damaged starch content increased. 相似文献
2.
Carla Moita Brites Carla Alexandra Lourenço dos Santos Ana Sofia Bagulho Maria Luísa Beirão-da-Costa 《European Food Research and Technology》2008,226(5):1205-1212
Puroindoline a and b (Pina, Pinb) form the molecular basis of bread wheat grain hardness. Varieties with a softer endosperm and a wild genotype, in which
both Pina and Pinb were present, seemed to produce less damaged starch flour than hard varieties, where Pin mutations occurred and changed the starch rheological properties. The functional property of starch samples extracted from
wheat varieties with different Pin alleles was evaluated. Starch morphology was characterized by scanning electron microscopy and laser light scattering. Thermal
properties were evaluated by differential scanning calorimetry. Amylose content, starch damage and rapid visco-analyser (RVA)
parameters were also determined. Significant variations (P < 0.05) were identified between different Pin variants for the distribution pattern of starch granule volume, amylose content, starch damage, RVA viscosity breakdown and
retrogradation, gelatinisation transition temperatures and enthalpies. Hard genotypes presented higher medium diameter granules
and lower enthalpic values. However, the differences detected are more evident among varieties that present both Pina and Pinb, than among those presenting only one of the two (a or b). 相似文献
3.
Chong Liu Limin Li Jing Hong Xueling Zheng Ke Bian Yu Sun Jie Zhang 《International Journal of Food Science & Technology》2014,49(1):253-260
Wheat flour was ground in an ultrafine pulveriser to obtain different levels of damaged starch (DS). The effect of DS content on physicochemical properties of flour and quality attributes of Chinese noodles and northern‐style Chinese steamed bread were investigated. Results showed that the degree of starch damage raised from 6.54% to 12.06% as grinding intensity increased from 0 to 130 Hz (P < 0.05). The falling number, sedimentation value, starch pastes' viscosity, dough proofing stability were negatively, while water absorption, pastes thermal stability, the degree of starch pastes and dough level were positively correlated with DS content, respectively (P < 0.05). The increase in DS content from 6.54% to 8.86% did not lead to a deterioration of texture characteristic, which might be attributed to the slight declining in hardness while enhancing in springiness and cohesiveness. The flour with DS content of 6.54–9.66% was suitable for steamed bread making. 相似文献
4.
Dynamic rheological and thermal properties of acetylated sweet potato starch (SPS) pastes (5%, w/w) were evaluated as a function of the degree of substitution (DS). The transition temperatures (To, Tp and Tc) and enthalpy of gelatinization (ΔH) of acetylated SPS, which were determined using differential scanning calorimetry, were lower than those of native starch, and significantly decreased with an increase in DS. Magnitudes of storage modulus (G′), loss modulus (G′′) and complex viscosity (η*) of acetylated SPS pastes were determined using a small‐deformation oscillatory rheometer. Dynamic moduli (G′, G′′ and η*) values of acetylated SPS pastes except for 0.123 DS were higher than those of native starch, and they also decreased with an increase in DS. The tan δ (ratio of G′′/G′) values (0.37–0.39) of acetylated SPS samples were lower than that (0.44) of native starch and no significant differences were found among acetylated SPS samples, indicating that the elastic properties of SPS pastes were affected by acetylation but did not depend on DS. The G′ values of acetylated SPS during aging at 4°C for 10 h were much lower than those of native starch, showing that the addition of acetyl groups produced a pronounced effect on the retrogradation properties of SPS. 相似文献
5.
Jin Xu Xuerong Fan Yawei Ning Pei Wang Zhengyu Jin Huanhuan Lv Baocai Xu Xueming Xu 《Food Hydrocolloids》2013
The influence of spring dextrin (SD) on the gelatinized starch retrogradation was investigated by wide X-ray diffraction (WXRD), differential scanning calorimetry (DSC) and molecular dynamic (MD) simulation. Different wheat and corn starch gels were prepared with the addition of SD3, SD5, SD7 or SD9. WXRD results showed that recrystallinity of wheat and corn starch gels was reduced with the addition of SD7 or SD9. Alternatively, SD3 or SD5 accelerated recrystallinity. Enthalpies of retrograde wheat and corn starch gels were analyzed using the Avrami equation and confirmed the WXRD results. Finally, MD simulation was adapted to predict the interaction of SD and starch fraction in water, and the results showed that the SD disturbed starch retrogradation by altering starch fraction–starch fraction interaction. Based on the obtained results of WXRD, DSC and MD, it was concluded that the addition of SDs significantly influences starch long-term retrogradation. 相似文献
6.
Fritillaria ussuriensis Maxim. starch acetates with different degrees of substitution (DSs) were prepared by reacting native starch with glacial acetic acid/acetic anhydride using sulfuric acid as catalyst. XRD of acetylated starch revealed that there was loss of crystallinity with increasing DS. The carbonyl group signal at 1750 cm−1 appeared in the FTIR spectra. The intensity of this peak increased whereas the intensity of the hydroxyl groups at 3000–3600 cm−1 decreased. The thermal behavior of the samples was investigated and the results showed that the acetylation decreased the gelatinization temperatures and ΔHgel, and thermal stability of high DS acetylated starch (DS = 2.82) was much better than that of the original starch and partially substitute starch acetate (DS = 1.52). The SEM suggested that most of the starch granules were disintegrated into many visible fragments along with the increasing of DS. The starch acetate with different DS prepared in this paper has many potential uses in food and pharmaceutical applications for its lower gelatinization temperature and thermal stability properties. 相似文献
7.
Starches from 15 Indian sorghum cultivars were separated and evaluated for physicochemical, morphological, thermal, retrogradation, pasting and textural properties. The morphological characterisation revealed the presence of irregular-polyhedral as well as spherical shaped granules. A wide variation in amylose content ranging from 11.2% to 28.5% was observed. Thermal, retrogradation, pasting and textural characteristics also showed significant differences amongst all the starch cultivars. Principal component analysis was carried out to extract five principal components that could explain 75% of the total variance. The first two principal components PC1 (To, Tp, Tc and ΔHgel) and PC2 (amylose content, range of gelatinisation, PHI and pasting and textural properties) could explain a cumulative variance of 44%, indicating the importance of amylose, thermal and textural properties on the sorghum starch functionality. 相似文献
8.
Techno‐functional properties of wheat flour‐resistant starch mixtures applied to breadmaking 下载免费PDF全文
Carlos Gabriel Arp María Jimena Correa Ángela Zuleta Cristina Ferrero 《International Journal of Food Science & Technology》2017,52(2):550-558
Resistant starch can be used to reduce the availability of carbohydrates in baked products. In this study, the effect of type 4 resistant wheat starch (RS4) on wheat flour dough and breads was evaluated. Wheat flour was substituted by RS4 at 10%, 20% and 30% w/w (RS10, RS20 and RS30, respectively). Rheological and thermal behaviours of dough were evaluated. Besides, bread quality, starch digestibility and bread staling were analysed. All substituted dough exhibited viscoelastic behaviour but lower elastic and viscous moduli. Regarding to bread quality, specific volume and crumb texture were negatively affected in samples with RS4. However, all samples were technologically acceptable. During storage, crumb hardening was observed in breads without and with RS4 but amylopectin retrogradation was not particularly affected. The in vitro digestibility of bread with RS showed a lower release of reducing sugars and a lower estimated glycaemic index, suggesting a healthier profile for these breads. 相似文献
9.
《Food research international (Ottawa, Ont.)》2003,36(7):729-737
Starch inclusion complexes with mono- and diacyl-sn-glycerophosphatidyl-choline (GPC) having various acyl (myristoyl, palmitoyl, stearoyl) chain lengths were studied. The physicochemical properties, such as the iodine affinities; crystallinity; water sorption and thermal properties of the defatted starch inclusion complexes were examined. Iodine affinity and thermal properties of the complex showed that 1- or 2-monomyristoyl-sn-GPC had the highest complexing ability, followed by decrease with the increasing chain length of GPC. Fourier transform infrared spectroscopy (FT-IR) revealed an increasing peak area ratio at 1654 cm−1, which is correlated with the increase in water sorption of starch–GPC. The water sorption and degree of crystallization strongly correlated with enthalpy value of starch gelatinization and starch–GPC complex formation. According to the Avrami equation, the retrogradation rate of starch–monoacyl-sn-GPC complex was slower than the starch–diacyl-sn-GPC complex during storage, whereas the retrogradation rates of 1- and 2-monomyristoyl-sn-GPC were the slowest among the GPCs. 相似文献
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11.
Sawomir Pietrzyk Lesaw Juszczak Teresa Fortuna Maria abanowska Ewa Bidziska Katarzyna Boniarczyk 《Starch - St?rke》2012,64(4):272-280
The study investigates the influence of Cu(II) ions used as a catalyst on the effectiveness of potato starch oxidation by hydrogen peroxide, and compares the physicochemical properties of the modified starches. The starch was oxidised by H2O2 alone and with the addition of Cu(II) ions at three concentrations: 0.1, 0.2 or 0.3 g per 100 g d.m. of starch. The oxidised starches were examined for the content of carboxyl groups, carbonyl groups, amylose and copper, and for water‐binding capacity and water solubility at temperatures of 60 and 80°C. Colour parameters (L*a*b*), susceptibility to retrogradation, thermodynamic characteristics of pasting, intrinsic viscosity and pasting characteristic by RVA were also determined. The results indicate that the concentration of Cu(II) ions added as a catalyst has an effect on both the effectiveness of the oxidation process and the physicochemical properties of starch. 相似文献
12.
The adsorption onto a softwood pulp of cationic modified starches with a degree of substitution (DS) ranging from 0.015 to 0.130 and native potato starch was investigated using a method based on size exclusion chromatography‐multi angle laser light scattering (SEC‐MALLS). This technique provides information about the amount and molecular composition of the adsorbed starch product such as the AP–AM‐ratio, the average MW and molar mass distribution. Factors influencing adsorption, like the electrolyte content in the suspension and the initial starch polysaccharide concentration, were investigated. Furthermore, hand sheets were made and the resulting mechanical paper strength was tested. Results were analysed statistically using analysis of variance. Representative results were discussed in detail. In general, low‐substituted cationic starch (DS 0.030) exhibited a higher degree of adsorption and resulted in high paper strength when there was a low electrolyte content in the starch–pulp‐suspension. However, high amounts of electrolytes impeded electrostatic interaction of the charged groups of the starch polysaccharides and cellulose fibre due to partial screening and therefore strongly limited adsorption. This resulted in lowered mechanical paper strength. The water quality of the suspensions had little impact on the polyelectrolyte adsorption of the highly substituted cationic starch (DS 0.100). However, paper strength was markedly higher in the case of starch adsorption where there was a high ionic content and when both starch polysaccharides–AP and AM– were adsorbed. The initial starch concentration determined starch adsorption both quantitatively and qualitatively and subsequently paper strength as well. The relation between adsorption behaviour and paper strength was discussed, particularly in the case of 6% initial starch concentration. In deionised water (DW), the low‐substituted starch (DS 0.03) adsorbed onto the pulp to a greater extent with an AP–AM‐ratio similar to that of the initial starch. Moreover, this achieved the best strength properties in contrast to 36 dGH, where less starch adsorbed and that being almost exclusively AP. In water with 36 dGH, the highly substituted starch (DS 0.100) with both the AP and AM was absorbed and this resulted in higher paper strength. In contrast, AM was almost exclusively adsorbed in DW. Increasing the initial starch concentration increased the amount adsorbed while subsequently changing the AP–AM‐ratio towards increased AM adsorption and decreased AP adsorption in the case of DS 0.100 in DW. Exclusive adsorption of AM markedly lowered the development of the paper strength. 相似文献
13.
An increasing amount of research suggests a relationship between the glass‐transition temperature (Tg) and the optimum storage temperature for a frozen food. In addition, the Tg for a frozen food is related to the cooling rate through the temperature range of phase transition for water. The objectives of this study were to investigate the influence of Tgon the rate of starch retrogradation during low‐temperature storage. Rice starch with 65% w/w water content was heated to obtain starch gel as a model food. The influences of cooling rate, storage temperature and time on rate of retrogradation were evaluated. Differential scanning calorimetry was used to measure the Tgand the enthalpy during retrogradation. Results indicated that the retrogradation rate during storage was reduced at a slower cooling rate. The retrogradation rates at storage temperatures above Tgwere higher than at storage temperatures below Tg. 相似文献
14.
Edith Agama‐Acevedo Francisco J. Garcia‐Suarez Felipe Gutierrez‐Meraz Mirna M. Sanchez‐Rivera Eduardo San Martin Luis A. Bello‐Prez 《Starch - St?rke》2011,63(3):139-146
Taro starch was isolated from Mexican variety and its morphological, physicochemical, and molecular characteristics were evaluated. Yield starch (in dry basis) was 81%, and this starch had low AM content (2.5%). Taro starch granules showed a mixture of shapes with sizes between 1 and 5 µm. Taro starch presented an A‐type XRD pattern with a crystallinity level of 38.26%. Solubility and water retention capacity did not change in the temperature range of 50–70°C and thereafter they increased as temperature increased too. Taro starch showed high peak viscosity due to its high AP content. The peak temperature of gelatinization of taro starch was 80.6°C with an enthalpy value of 10.6 J/g, with low retrogradation rate due to its low AM content. Weight‐average molar mass (Mw) and gyration radius (Rz) of taro starch were 1.21 ± 0.8 × 109 g/mol and 424 ± 70 nm, respectively. Taro tuber could be an alternative for starch isolation with functional and physicochemical characteristics for food and non‐food applications. 相似文献
15.
Impact of the addition of resistant starch from modified pea starch on dough and bread performance 总被引:1,自引:0,他引:1
Juan Mario Sanz-Penella Małgorzata Wronkowska Maria Soral-Śmietana Concha Collar Monika Haros 《European Food Research and Technology》2010,231(4):499-508
The interest in the use of resistant starch (RS) for the development of new bakery products has significantly increased due
to its ascribed physiological effects with proven health benefits. The objective of the present work was to analyse the effects
of the wheat flour substitution by modified pea starch with high level of RS (PeaP) on breadmaking performance. The effects
of PeaP on wheat dough functionality were evaluated by mixing/overmixing properties, texture profile analysis, viscometric
profile and thermal properties. Bread quality was evaluated by physico-chemical parameters, crumb texture profile, digital
image analysis, nutritional parameters and sensory evaluation. Flour substitution by PeaP up to 20% allowed keeping mechanical,
extensional and viscometric parameters without significant hindering of dough machinability. Overdose of modified pea starch
(30%) negatively affects dough mixing and overmixing behaviour. As a functional/prebiotic fibre, PeaP addition up to 10–20%
of flour replacement entitles the formulation of wheat bread allowing a significant increase in the RS level (from 0.70 to
5.10%), delay/decrease in amylopectin retrogradation, with acceptable changes in bread quality up to 10–20% of flour replacement. 相似文献
16.
Xin Wang Sung‐Gil Choi William L Kerr 《Journal of the science of food and agriculture》2004,84(4):371-379
The effect of gluten on starch retrogradation at 5 °C was studied using 1H NMR relaxometry. Gels were made from gluten and starch at 27.8 and 38.5% total solids and with gluten comprising either 10, 15 or 20% of the solids. Changes in the transverse relaxation time constant (T2) were related to water mobility. Mono‐exponential analysis of relaxation curves showed that, in general, gluten retarded starch retrogradation. T2 values in gluten gels also decreased during storage, but to a much lesser extent. Distributed exponential analysis showed that two distinct regions of T2 were observed in all samples. During aging, the peak values of both regions shifted to lower values for all gels. Starch gel samples showed the most significant shift, and gluten gels showed the least. The three levels of gluten addition in starch/gluten gels produced similar shifts. For all samples the signal intensity of the less mobile region decreased more dramatically than that of the more mobile region during storage. It was suggested that gluten retards water loss in the granule remnants. Copyright © 2004 Society of Chemical Industry 相似文献
17.
老化对淀粉的生理效价和生物降解具有决定性作用,糊化淀粉在存放过程中,淀粉分子发生自组,其直链淀粉及支链淀粉的直线部分趋向于平行排列,从无定形态回复到晶体态,出现老化现象,会导致淀粉基生物材料产品的品质和性能大幅降低。本课题对直链淀粉含量、水分含量及乳化剂种类对糯质小麦淀粉老化特性的影响进行研究,比较乳化剂对糯质小麦淀粉及普通小麦淀粉老化特性影响的异同。结果表明:直链淀粉的含量、水分含量都与糊化淀粉的老化程度呈正相关。直链淀粉的含量是决定淀粉老化程度的最主要因素,乳化剂与淀粉分子相互作用形成稳定的复合物,减缓了淀粉的老化。同时乳化剂的复配能一定程度地加强抗老化的效果。总体上讲,糯质小麦淀粉的各种良好的理化特性,使其在淀粉基生物材料抗老化上有更好的应用前景。 相似文献
18.
Starch samples separated from oat were modified with two different levels of POCl3 (0.5 and 1.0 g kg−1) as a cross-linking agent and two different levels of acetic anhydride (6% and 8% (w/w)) for acetylation. Swelling factor, thermal properties and retrogradation measurements were evaluated to characterise the influence of phosphorylation and acetylation on oat starch. Cross-linking decreased the swelling factor and did not improve gelatinization temperature while it increased synaeresis in comparison with native starch. Acetylation increased swelling factor but reduced gelatinization temperature and synaeresis of oat starch. 相似文献
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20.
Thermal stable polysaccharides from Auricularia auricula-judae (AP) have unique molecularstructures and multiple bioactivities. The effects of AP on the physicochemical properties and in vitro starch digestibility of yam starch (YS) were studied. The addition of AP induced a significant increase in the swelling power, solubility, mean volume diameter and adhesiveness as well as a dramatic decrease in the hardness and gumminess (p?<?0.05). AP showed a strong suppressive effect on in vitro starch digestibility. Higher modulus (G′, G″) and stiffness parameters (Aα), and lower order of relaxation function (α), were observed in oscillatory rheological measurements, indicating that the gels were more elastic-like and had higher pseudoplasticity in the presence of AP. Furthermore, AP remarkably decreased the syneresis and storage modulus (G′), and also retarded the retrogradation process of YS gel at 4°C, revealing a synergistic interaction between AP and YS, which could also be demonstrated by scanning electron microscopy. 相似文献