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1.
The objective of this study was to observe the influence of differences in genotype (variety) and protein concentration on batter flow and pancake making performance of a collection of soft white winter wheats. Wheats were chosen to express contrasting absorption characteristics and oxidative gelation potentials. Pancakes were processed with two formulations, one (“old”) with egg, soy, and dairy and one (“new”) without. Pancake performance was compared with grain, milling, flour, solvent retention capacity (SRC), pasting, and oxidative gelation characteristics of the flours. Kernel texture, break flour yield, carbonate SRC, and lactic acid SRC were not significantly associated with pancake performance for either formulation. ANOVA showed that flour protein concentration had a dominant effect on pancake batter flow and dimensions. Flour protein concentration affected pancakes more than flour protein quality (lactic acid SRC). Water and sucrose SRCs and Rapid Visco Analyzer pasting temperature were negatively correlated with pancake batter flow and dimensions. Pasting temperature was significantly and positively correlated with flour protein, suggesting that correlations with pancake properties might be simply a cross‐correlation with protein concentration. Notably, and in contrast to our hypothesis, oxidative gelation potential had no relationship with pancake processing or quality.  相似文献   

2.
Enzymatic treatments known to induce the gelation of feruloylated arabinoxylans solutions were applied to tissue strips isolated from peripheral layers of wheat grain to tentatively produce in situ arabinoxylan reticulation. The treatments by horseradish peroxidase (HRP) and manganese dependent peroxidase (MnP) induced a dimerization of ferulic acid (FA) in wheat bran with concomitant decrease of arabinoxylan solubility. Similar results were obtained, but to a lesser extent, by simple incubation of bran strips in water, suggesting the action of endogenous peroxidases. The fact that these treatments proved to be ineffective on the isolated aleurone layer and pericarp suggested that dimerization occurred mostly at the aleurone-pericarp interface. In addition, the MnP system generated a consumption of monomer and dimer of ferulic acid in the pericarp, perhaps due to their incorporation into lignin. Micro-mechanical tests using DMTA were performed on isolated tissue strips and showed that oxidation of wheat bran increased their mechanical strength (increase of stress and strain to rupture).  相似文献   

3.
The effects of a laccase from the fungus Pycnoporus cinnabarinus on the mixing of a wheat flour dough with or without added ferulic acid (FA) were studied. Laccase reduced dough time‐to‐peak and accelerated dough breakdown in comparison with the control. Its effect was enhanced with FA. The water extractability of arabinoxylans (AX) increased during mixing of a dough free of added laccase, especially with exogenous FA. At the same time, the extractability of FA decreased during mixing. Added FA may have competed with endogenous AX feruloyl esters, inhibiting partly oxidative gelation. Laccase decreased AX extractability by chain cross‐linking through oxidative dimerization of feruloyl esters. FA and, moreover, FA plus laccase, increased the oxidation of sulfhydryl (SH) groups. FA and, even more, FA in combination with laccase, increased the rate of protein depolymerization during mixing. FA and the products of FA laccase oxidation participated in a redox reaction involving SH groups. A coupling reaction involving enzymatically generated feruloyl radicals and thiol radicals generated through the mechanical breakdown of inter‐chain disulfide bonds might explain these results.  相似文献   

4.
We evaluated the effect and magnitude of flour particle size on sponge cake (SC) baking quality. Two different sets of wheat flours, including flours of reduced particle size obtained by regrinding and flour fractions of different particle size separated by sieving, were tested for batter properties and SC baking quality. The proportion of small particles (<55 μm) of flour was increased by 11.6–26.9% by regrinding. Despite the increased sodium carbonate solvent retention capacity, which was probably a result of the increased starch damage and particle size reduction, reground flour exhibited little change in density and viscosity of flour‐water batter and produced SC of improved volume by 0.8–15.0%. The volume of SC baked from flour fractions of small (<55 μm), intermediate (55–88 μm), and large (>88 μm) particles of soft and club wheat was in the range of 1,353–1,450, 1,040–1,195, and 955–1,130 mL, respectively. Even with comparable or higher protein content, flour fractions of intermediate particle size produced larger volume of SC than flour fractions of large particle size. The flour fractions of small particle size in soft white and club wheat exhibited lower flour‐water batter density (102.6–105.9 g/100 mL) than did those of large and intermediate particle fractions (105.2–108.2 g/100 mL). The viscosity of flour‐water batter was lowest in flour fractions of small particle size, higher in intermediate particles, and highest in large particles. Flour particle size exerted a considerable influence on batter density and viscosity and subsequently on SC volume and crumb structure. Fine particle size of flour overpowered the negative effects of elevated starch damage, water absorption, and protein content in SC baking.  相似文献   

5.
Relationships among soft wheat quality parameters relating to sponge cake volume and sensory tenderness were investigated. Sixteen soft wheats from the 2008–2009 crop and 11 from the 2009–2010 crop, including Japanese soft wheat cultivars, advanced breeders' lines, and western white wheat imported from the United States, were milled and evaluated for protein content, sucrose solvent retention capacity value, specific surface area, flour pasting properties, batter pasting viscosity, sodium dodecyl sulfate sedimentation (SDSS) volume, farinograph properties, specific cake volume, and sensory tenderness score to investigate their relationships. Batter pasting viscosity was measured with a Rapid Visco Analyzer (RVA) at 2 min after reaching 90°C in heating a mixture with equal weights of flour, sucrose, and water. RVA minimum viscosity of flour suspension in water was the most influencing factor and positively correlated to specific cake volume, and RVA batter pasting viscosity and SDSS volume were negatively correlated. Meanwhile, protein content and SDSS volume were strongly negatively correlated with sensory tenderness score. Stepwise multiple regression analysis selected protein content and specific cake volume as independent variables to predict sensory tenderness score; however, SDSS volume and farinograph properties relating to protein strength were not selected. Protein content affected sponge cake tenderness independently of specific cake volume, which was related to differences in cake density.  相似文献   

6.
Arabinoxylans (AX) are well known to have a wide‐ranging influence on wheat (Triticum aestivum L.) end‐use quality and are associated with health benefits. There is little information on the effects of processing on AX properties in high‐water‐content batter‐based products and on the associations between AX properties and end‐use quality in such products. The objective of this study was to track total and water‐extractable AX (TAX and WEAX, respectively) contents and determine changes in AX characteristics throughout the baking process of pancakes, a batter‐based wheat product. The TAX and WEAX contents along with the arabinose‐to‐xylose (A/X) ratio were quantified in refined flour and wholemeal as well as batter and pancakes from two soft and three hard wheat varieties. ANOVA F values indicated that the variation in TAX content was influenced most by sample type differences (flour versus batter versus pancakes), whereas varietal differences were responsible for the greatest differences in WEAX. In separate analyses on refined and wholemeal flours, the highest F values were for variety WEAX, largely attributed to the higher WEAX content of the three hard varieties. WEAX levels generally increased slightly from flour to batter to pancakes in refined flour. The WEAX content in flour, batter, and pancakes of both refined flour and wholemeal was highly correlated with pancake volume. These observations suggest moderate changes in wheat AX characteristics during processing and a positive association of WEAX levels with end‐product volume in a batter‐based product.  相似文献   

7.
The effect of sequential acid, alkaline, and enzymatic treatment of chickpea and lentil flours on batter rheological properties was investigated. Substitution of wheat with disrupted chickpea and lentil flours significantly (P < 0.05) increased water‐holding capacity from 66.8% in wheat flour to more than 70.0% based on the disruption treatment, indicating an improved adhesion of coated batter. Flow behavior index of batter treatments of partially replaced wheat flour with various ratios of disrupted chickpea and lentil flours ranged from 0.88 to 1.36 and was significantly (P < 0.05) lower than the flour (i.e., 2.15) and nondisrupted control (i.e., 1.28–1.38 for chickpea and 1.22–1.28 for lentil) flours. Consistency coefficients of disrupted chickpea and lentil flours were significantly (P < 0.05) greater when replacing wheat control, indicating a best fit for the shear‐thickening model. Flour disruption decreased the treatment's pasting properties, except the setback, providing support for the significant role of proteins in dictating the pasting characteristics of batter flour treatments. Results of this study suggested a potential use for treated chickpea and lentil flours in enhancing batter rheological properties including adhesion and water‐holding capacity.  相似文献   

8.
Arabinoxylans are a minor but important constituent in wheat that affects bread quality, foam stability, batter viscosity, and sugar snap cookie diameter. Therefore, it is important to determine the distribution of arabinoxylans in flour mill streams to better formulate flour blends. Thirty‐one genetically pure grain lots representing six wheat classifications common to the western U.S. were milled on a Miag Multomat pilot mill, and 10 flour mill streams were collected from each. A two‐way ANOVA indicated that mill streams were a greater source of variation compared to grain lots for total arabinoxylans (TAX), water‐unextractable arabinoxylans (WUAX), and water‐extractable arabinoxylans (WEAX). TAX and WUAX were highly correlated with ash at r = 0.94 and r = 0.94, respectively; while the correlation for WEAX and ash decreased in magnitude at r = 0.60. However, the 5th middlings mill streams exhibited disparity between TAX and ash content as well as between WUAX and ash content. This may indicate that TAX and WUAX in mill streams are not always the result of bran contamination. Cumulative extraction curves for TAX, WUAX and WEAX revealed increasing gradients of arabinoxylans parallel to extraction rate. Therefore, arabinoxylans may be an indicator of flour refinement.  相似文献   

9.
Batters were prepared, using rice flour as the main component, and analyzed for their oil uptake properties during frying. Rice flour resisted oil absorption better but was less effective as a thickening agent than wheat flour. Of the rice components, increased amylose in the amylopectin/amylose ratio of the starch decreased the batter oil uptake, whereas increased protein content had the opposite effect. Various additives were introduced and investigated for their ability to develop viscosity and other desirable characteristics for the batter. As additives to the rice flour batters, phosphorylated starch and gelatinized rice flour enhanced both the thickening and oil-reducing capacities of the batter. Compared with values for batters from wheat flour, the percent batter oil uptake in the fried crust for the modified rice flour batters was decreased by up to 62%, and the percent total oil uptake for the whole coated drumstick was reduced by up to 59%.  相似文献   

10.
The quality of many baked products, noodles, gravies, and thickeners is related to the pasting properties of wheat (Triticum aestivum L.) flour, yet different flours vary markedly in their pasting performance. The objective of the present research was to assess the role of the wheat flour fractions, gluten, water solubles, prime and tailing starches, in the contribution to peak hot paste viscosity among three selected wheat cultivars. Straight-grade flours were fractionated and reconstituted. Fractions were examined independently and were deleted in otherwise fully reconstituted flours. Fractions were exchanged between cultivars for reconstituting flours, and fractions were substituted individually into a common starch base. The flours from the cultivars Klasic, McKay, and Madsen differed markedly in their peak hot paste viscosities, and were fractionated and reconstituted with only a small effect on paste viscosity. Results clearly showed that prime starch was the primary determinate of flour paste viscosity, but the other fractions all exerted a significant effect. Tailing starch increased paste viscosity directly due to pasting capacity of starch or indirectly through competition for water. Gluten also increased paste viscosity through competition for water. The water-soluble fraction from different cultivar flours was more variable in effect.  相似文献   

11.
The Rapid Visco Analyzer (RVA) was investigated as a tool to measure oxidative gelation capacity (OGC) of aqueous wheat flour suspensions. One club wheat patent flour was used to determine optimal hydration time, and 33 straight‐grade flours (representing 12 hard and 21 soft varieties) were used to observe varietal differences in OGC. A 33.3% w/w flour–water suspension was tested in the RVA at 30°C and 160 rpm for 1 min to establish the flour–water baseline viscosity, and then 65 μL of 3% H2O2 was added and the viscosity of the suspension measured at 160 rpm for a further 5 min. Flour from the club wheat showed that 20 min of prehydration was needed to observe full OGC potential. For the 33 straight‐grade flours, final RVA water baseline viscosity was correlated with Bostwick Consistometer (BC) flow (r = −0.93, P ≤ 0.01), and RVA H2O2 peak viscosity was correlated with H2O2 BC flow (r = –0.81, P ≤ 0.01). The RVA was able to differentiate H2O2‐reactive from nonreactive flours. The RVA can observe phenomena not observable with the BC method (e.g., viscosity reduction over time at constant shear rate), which can provide potentially valuable additional information about the nature of OGC in wheat flour suspensions.  相似文献   

12.
The effects of ferulic acid and transglutaminase (TG) on the properties of wheat flour dough and bread were investigated. Ferulic acid and TG were blended with hard wheat flour at levels of 250 and 2,000 ppm of flour weight, respectively. The addition of ferulic acid reduced the mixing time and mixing tolerance. The addition of TG did not obviously affect the mixing properties. Significant effects of ferulic acid plus TG on the rested dough texture were observed for overmixed dough. The maximum resistance (Rmax) of the dough was significantly reduced with the addition of ferulic acid but increased with the addition of TG. The addition of TG with ferulic acid restored the Rmax reduced by ferulic acid alone. The proportion of SDS‐soluble high molecular weight proteins in the dough increased with the addition of ferulic acid and decreased with TG, when assessed with size‐exclusion HPLC fractionation. Although the addition of TG improved the handling properties of the dough made sticky with added ferulic acid, it did not improve the quality of the bread with added ferulic acid as measured by loaf volume and firmness.  相似文献   

13.
Thirteen different wheat cultivars were selected to represent GBSS mutations: three each of wildtype, axnull, and bxnull, and two each of 2xnull and waxy. Starch and A‐ and B‐granules were purified from wheat flour. Hearth bread loaves were produced from the flours using a small‐scale baking method. A‐granules purified from wildtype and partial waxy (axnull, bxnull, and 2xnull) starches have significantly higher gelatinization enthalpy and peak viscosity compared with B‐granules. A‐ and B‐granules from waxy starch do not differ in gelatinization, pasting, and gelation properties. A‐ and B‐granules from waxy starch have the highest enthalpy, peak temperature, peak viscosity, breakdown, and lowest pasting peak time and pasting temperature compared with A‐ and B‐granules from partial waxy and wildtype starch. Waxy wheat flour has much higher water absorption compared with partial waxy and wildtype flour. No significant difference in hearth bread baking performance was observed between wildype and partial waxy wheat flour. Waxy wheat flour produced hearth bread with significantly lower form ratio, weight, a more open pore structure, and a bad overall appearance. Baking with waxy, partial waxy, and wildtype wheat flour had no significant effect on loaf volume.  相似文献   

14.
End‐use quality in soft wheat (Triticum aestivum L.) can be assessed by a wide array of measurements, generally categorized into grain, milling, and baking characteristics. Samples were obtained from four U.S. regional nurseries. Selected parameters included test weight, kernel hardness, kernel size, kernel diameter, wheat protein, polyphenol oxidase activity, flour yield, break flour yield, flour ash content, milling score, flour protein content, flour SDS sedimentation volume, flour swelling volume, Rapid Visco Analyzer peak paste viscosity, solvent retention capacity (SRC) parameters, total and water‐extractable arabinoxylan (TAX and WEAX, respectively), and cookie diameter. The objectives were to model cookie diameter and lactic acid SRC as well as to compare exceptionally performing varieties for each quality parameter. Cookie diameter and lactic acid SRC were modeled by using multiple regression analyses and all of the aforementioned quality parameters. Cookie diameter was positively associated with peak paste viscosity and was negatively associated with or modeled by kernel hardness, flour protein content, sodium carbonate SRC, lactic acid SRC, and water SRC. Lactic acid SRC was positively modeled by break flour yield, milling score, flour SDS sedimentation volume, and sucrose SRC and was negatively modeled by flour protein content. Exceptionally high‐ and low‐performing varieties were selected on the basis of their responses to the aforementioned characteristics in each nursery. High‐ and low‐performing varieties exhibited notably wide variation in kernel hardness, break flour yield, milling score, sodium carbonate SRC, sucrose SRC, water SRC, TAX content, and cookie diameter. This high level of variation in variety performance can facilitate selection for improved quality based on exceptional performance in one or more of these traits. The models described allow a more focused approach toward predicting soft wheat quality.  相似文献   

15.
The starch of wheat (Triticum aestivum L.) flour affects food product quality due to the temperature-dependent interactions of starch with water during gelatinization, pasting, and gelation. The objective of this study was to determine the fundamental basis of variation in gelatinization, pasting, and gelation of prime starch derived from seven different wheat cultivars: Kanto 107, which is a partial waxy mutant line, and six near-isogenic lines (NILs) differing in hardness. Complete pasting curves with extended 16-min hold at 93°C were obtained using the Rapid Visco Analyser (RVA). Apparent amylose content ranged from 17.5 to 23.5%; total amylose content ranged from 22.8 to 28.2%. Starches exhibited significant variation in onset of gelatinization. However, none of the parameters measured consistently correlated with onset or other RVA curve parameters that preceded peak paste viscosity. Peak paste viscosity varied from 190 to 323 RVA units (RVU). Higher peak, greater breakdown, lower final viscosity, negative setback, and less total setback were associated with lower apparent and total amylose contents. Each 1% reduction in apparent or total amylose content corresponded to an increase in peak viscosity of about 22 and 25 RVU, respectively, at 12% starch concentration. Of the seven U.S. cultivars, the lower amylose cultivars Penawawa and Klasic were missing the granule-bound starch synthase (GBSS; ADPglucose starch glycosyl transferase, EC 2.4.4.21) protein associated with the Waxy gene locus on chromosome 4A (Wx-B1 locus). Kanto 107 was confirmed as missing both the 7A and 4A waxy proteins (Wx-A1 and Wx-B1 loci). The hardness NIL also were shown to be null at the 4A locus. Apparent and total amylose contents of prime starch generally corresponded well to the number of GBSS proteins; although the hardness NIL tended to have somewhat higher amylose contents than did the other GBSS 4A nulls. We concluded that reduced quantity of starch amylose due to decreased GBSS profoundly affects starch gelatinization, pasting, and gelation properties.  相似文献   

16.
Arabinoxylans are hydrophilic nonstarch polysaccharides found in wheat grain as minor constituents. Arabinoxylans can associate with large amounts of water through hydrogen bonding and can form oxidative gels. These properties are important factors in end‐use quality of wheat. The objective of this study was to delineate the influence of wheat cultivar and growing environment on variation in water‐soluble (WS‐AX), waterinsoluble (WI‐AX), and total (TO‐AX) arabinoxylan contents of flour and whole grain meal. This study included seven spring and 20 winter soft white wheat cultivars grown in 10 and 12 environments, respectively (each evenly split over two crop years). Univariate analysis of variance (ANOVA) and multivariate analysis of variance with canonical analysis (MANOVA) was used to evaluate sources of variation. Variation in arabinoxylan contents and absolute amounts (xylose equivalents) among the two cultivar sample sets (spring and winter) was similar, and both cultivar and environment were significant sources of variation. The cultivar‐by‐environment interaction was relatively unimportant. Results indicate that the variation in arabinoxylan content is primarily influenced by cultivar and secondarily influenced by environment. Within arabinoxylan fractions, WS‐AX content is primarily influenced by genotype, while WI‐AX content is more greatly influenced by the environment.  相似文献   

17.
The influence on wheat flour gluten-starch separation of a xylanase from Aspergillus aculeatus (XAA) with hydrolysis selectivity toward water extractable arabinoxylan (WE-AX) and that is not inhibited by wheat flour xylanase inhibitors was compared to that of a xylanase from Bacillus subtilis (XBS) with hydrolysis selectivity toward water unextractable arabinoxylan (WU-AX) and that is inhibited by such inhibitors. XAA improved gluten agglomeration through degradation of WE-AX and concomitant reduction in viscosity, which in the laboratory scale batter procedure with a set of vibrating sieves (400, 250, and 125 microm), increased protein recoveries on the 400 microm sieve. In contrast, XBS had a negative effect as it decreased gluten protein recovery on this sieve, probably as a result of the viscosity increase that accompanied WU-AX solubilization. Hence, it was active even if most likely a considerable part of its activity was prevented by xylanase inhibitors. A combination of XAA and XBS at a low dosage yielded a distribution of gluten proteins on the different sieves comparable to that of the control. At a high combined dosage, the gluten agglomeration was better than that with XAA alone, indicating that both WE-AX and WU-AX have a negative impact on gluten agglomeration. Finally, experiments with endoxylanase addition at different moments during the separation process suggest that the status of the arabinoxylan population during dough mixing is far less critical for its impact on gluten agglomeration than that during the batter phase.  相似文献   

18.
Water-extractable arabinoxylan (WE-AX) of variable molecular weight (MW) and water-unextractable arabinoxylan (WU-AX) were added to wheat flour to study their effect on gluten agglomeration in a dough and batter gluten-starch separation process with recovery of gluten from the batter with a set of vibrating sieves (400, 250, and 125 microm). Low MW WE-AX had almost no impact on the distribution of the gluten on the different sieves. High MW WE-AX decreased yields of the largest (400 microm sieve) gluten aggregates, more than their medium MW counterparts, indicating the importance of AX MW for their effect on gluten interactions. Correlations between the total level of gluten protein recovered on the three sieves and the batter extract viscosity as well as between the proportion of gluten protein recovered on the 400 microm sieve to that on the three sieves and the batter extract viscosity pointed to the importance of viscosity as an indicator for gluten agglomeration, as did the fact that another viscosity increasing plant polysaccharide (guar gum) also negatively influenced gluten agglomeration. However, the obtained data cannot rule out that AX and guar gum also exert steric effects on gluten agglomeration. WU-AX, present as discrete cell wall fragments, had a negative impact on the level of large gluten aggregates. Taken together, the results show that both native WE-AX and WU-AX detrimentally impact gluten agglomeration.  相似文献   

19.
In Japanese soft wheat (Triticum aestivum L.) breeding programs, protein content (PC), and specific surface area (SSA) of flour have been used as important factors for the baking quality of Japanese sponge cake. We proposed batter pasting viscosity (BPV) as a parameter to predict the baking quality of Japanese sponge cake. BPV was measured using a Rapid Visco‐Analyser (RVA) with a modified heating profile. Twenty soft wheat samples from the 2006‐07 season and 22 from the 2007‐08 season, including Japanese soft wheat cultivars, advanced breeders' lines, and Western White (WW) imported from the United States, were milled and evaluated for solvent retention capacity (SRC) values of four solvents, batter pasting properties, flour pasting properties, PC, SSA, and specific cake volume (SCV) to investigate their relationships. BPV was the most strongly correlated of the parameters to SCV (r = –0.90, P < 0.001). Stepwise multiple regression analysis selected BPV and minimum viscosity (MV) of flour pasting as significant independent variables to predict SCV (corrected R2 = 0.848). The variability in BPV related to cake batter expansion was highly explained by PC and sucrose SRC (corrected R2 = 0.854, P < 0.001). MV was correlated to SSA (r = 0.56, P < 0.001) and might be related to the prevention of sponge cake shrinkage during baking.  相似文献   

20.
Mineral content, as determined and expressed by ash content, serves as an index of wheat flour quality for flour millers and food manufacturers who prefer flour of low mineral content, even though the significance of mineral content on the functional properties of wheat flour is not well understood. We explored whether minerals have any influence on the functional properties of wheat flour and product quality of white salted noodles. Ash, obtained by incinerating wheat bran, was incorporated into two hard white spring wheat flours and their starches to raise the total ash content to 1, 1.5, or 2%. Pasting properties were determined using a rapid visco analyzer (RVA). Addition of ash increased the peak viscosity of the flours in both water and buffer solution but did not affect the peak viscosity of starch. Wheat flours with added ash showed lower pasting temperature by approximately 10°C in buffer solution. Mineral extracts (15.3% ash) isolated from wheat bran, when added to increase the ash content of wheat flour and starch to 2%, increased the peak viscosity and lowered the pasting temperature of flour by 13.2–16.3% but did not affect the pasting properties of the isolated starch. The mineral premix also increased peak viscosity of wheat flour but not in starch. Added ash increased noodle thickness and lowered water retention of cooked noodles while it exhibited no significant effect on cooked noodle texture as determined using a texture analyzer.  相似文献   

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