抗性淀粉对小麦粉面团流变学特性的影响

以3种不同筋力小麦粉为原料,研究了抗性淀粉对小麦粉面团流变学特性的影响。结果表明:两种抗性淀粉分别与3种筋力小麦粉以不同比例配粉后,配粉的揉混和拉伸特性呈现相同的变化趋势,随着抗性淀粉的添加,面团的峰值高度和8 min带高、最大拉伸阻力、延伸距离和拉伸面积均呈下降趋势。抗性淀粉的加入劣化了强筋和中筋粉的加工品质,但对弱筋粉加工品质影响较小。两种抗性淀粉对强、中、弱筋小麦粉配粉拉伸阻力的影响相同。配粉的拉伸面积和拉伸比值表明:15%RS以下的强筋粉配粉和5%RS中筋粉配粉适用于馒头和面条制作,5%~20%RS的弱筋粉配粉更适合于制作饼干和糕点。     

抗性淀粉对北方馒头加工品质的影响

研究了抗性淀粉(Resistant Starch,RS)对北方馒头加工品质的影响。结果表明:随着RS添加量的增加,三种筋力抗性淀粉馒头的硬度和咀嚼性显著增加,弹性、黏聚性和回复性显著减小。10%RS添加量的强筋粉馒头和5%RS添加量的中筋粉馒头的硬度和咀嚼性明显低于弱筋粉馒头,具有可接受的口感。抗性淀粉添加于小麦粉中,在一定程度上恶化了小麦粉的加工性能,具体表现为馒头僵硬、弹性差、感官评分较低。馒头的老化主要出现在初始24 h内,不同RS添加量馒头的老化趋势相同。     

抗性淀粉与小麦粉配粉对面包加工品质的影响

以2种不同筋力小麦粉为原料,研究了抗性淀粉对小麦粉面包加工品质的影响。结果表明:添加5%抗性淀粉的强筋粉面包的硬度和咀嚼性与原小麦粉面包相似,品质与原小麦粉面包相当。添加5%抗性淀粉的中筋粉面包的硬度和咀嚼性明显高于原小麦粉面包,品质略有下降。添加10%~15%抗性淀粉的强筋粉和中筋粉面包的硬度和咀嚼性显著增加,面包体积显著减小,弹柔性降低,口感发硬,表面色泽不匀,出现斑点,预示面包品质显著下降。相关分析表明:抗性淀粉面包的体积、外形、表皮质地、表皮色泽、芯色泽、平滑度、纹理结构、弹柔性和口感皆与面包评分呈极显著相关。     

小麦粉的溶剂保持力与其蛋白质含量及面筋黏弹性的关系

利用市售高筋、中筋和低筋小麦粉,按照一定比例混合制得混合粉,检测混合粉的蛋白质含量、微量水溶剂保持力和微量乳酸溶剂保持力,以及相应的面筋硬度、黏弹性等指标,进行相关性分析。结果表明:利用强筋和弱筋小麦粉按照一定比例配制成的混合粉,可以形成不同的蛋白质含量和不同筋力。微量乳酸SRC值与微量水SRC值和小麦粉蛋白质含量、面筋硬度及黏弹性均具有相关性,其中,小麦粉微量水SRC值与小麦粉蛋白质含量的相关性(R~2=0.809 0)高于微量乳酸SRC值与小麦粉蛋白质含量的相关性(R~2=0.782 6)。利用微量水SRC值可以判断小麦粉的蛋白质含量(筋力强弱),即当微量水SRC值大于52时为强筋粉,在51~52时为中筋粉,小于51时为弱筋粉。     

糯小麦粉配粉对小麦加工品质的影响(Ⅰ)对理化特性的影响

通过对2种糯小麦和3种非糯小麦理化特性进行比较研究,并利用其中1种糯小麦与非糯小麦配粉,研究其对配粉理化特性的影响。结果表明:糯小麦制粉过程中产生的破损淀粉含量更高,具有极高的吸水能力;在RVA糊化过程中具有较短的峰值时间,低的回生值和低谷黏度,以及较高的衰减值;在DSC测试中还表现出较高的热力学转变温度和糊化焓。糯小麦粉的添加对配粉理化特性的影响因基础粉的不同而有较大差异。配粉的RVA曲线表现为双峰,回生值显著降低;一定比例的添加能够提高峰值黏度低的基础粉的峰值黏度;添加糯小麦粉对弱筋小麦粉的筋力影响较小,其粉力甚至因为面团延伸性的改善而得到增强;对于筋力较强的小麦粉,超过15%的添加量则会使稳定时间降低,但是对粉力的影响不大;添加韧性和延伸性都较低的糯小麦粉,能够提高配粉的吹泡延伸性而不降低其韧性,其原因有待于进一步研究。     

蛋白质和淀粉对面团流变学特性和淀粉糊化特性的影响

以3个筋力不同的小麦粉为材料,利用分离重组方法,在保持小麦粉其他成分不变的情况下,组成不同面筋蛋白和淀粉含量的配粉,研究面筋蛋白和淀粉添加量对面团流变学特性和面粉糊化特性的影响。结果表明：随着面筋蛋白添加量的增加,3种筋力小麦粉配粉的面团稳定时间和粉质质量指数均呈升高趋势,峰值黏度、低谷黏度、最终黏度、稀懈值、回生值等总体呈下降趋势。小麦粉添加淀粉后,面团稳定时间和粉质质量指数均呈下降趋势,峰值黏度、低谷黏度、最终黏度、稀懈值、回生值等总体呈升高趋势。面筋蛋白和淀粉对小麦面团吸水率和面粉糊化温度的影响均较小。不同筋力小麦粉配粉各品质指标总体变化趋势一致,但变化幅度有一定差异。     

桔梗皂甙对玉米淀粉糊部分理化特性的影响

为了研究桔梗皂甙对玉米淀粉糊部分理化特性的影响,在玉米淀粉糊中添加桔梗皂甙,测定添加皂甙后玉米淀粉的颗粒形态、玉米淀粉糊的表观黏度、凝沉特性和淀粉糊形成的凝胶特性.结果表明,随着皂甙添加量的增大,淀粉颗粒变小,淀粉糊的黏度增加,抗凝沉能力增加;桔梗皂甙的添加也对淀粉糊形成的淀粉凝胶特性产生影响,玉米淀粉凝胶的凝胶强度、硬度、弹性、胶着性、咀嚼度及回复力与桔梗皂甙的添加量呈负相关,黏着性与桔梗皂甙的添加量呈正相关.桔梗皂甙可对玉米淀粉性能产生一定的影响.     

糯小麦粉配粉对小麦加工品质的影响(Ⅱ)对面条品质影响的研究

利用1种糯小麦粉与2种非糯小麦粉配粉,研究其对配粉面条品质的影响。结果表明:糯小麦粉对面条感官评价中的色泽、食味影响较小,而对面条表观状态、韧性、黏性和光滑性影响较大。糯小麦粉的添加使得面条韧性降低,一定比例的添加有利于黏性和光滑性的改善,25%的糯小麦粉与非糯小麦粉配粉使得面条总评分最高。面条TPA测试中,糯小麦粉的添加使得面条硬度值、胶着性和咀嚼性随着配比的增加而降低,黏附性、黏聚性和回复性随着配比的增加而上升;糯小麦粉的添加还使得面条的剪切应力降低,一定比例的糯小麦配粉有利于面条延伸性的改善。     

玉米抗性淀粉的添加对面条品质的影响

以普通玉米淀粉为原料,经高温高压蒸煮、冷却、回生后,制备RS3型玉米抗性淀粉,按一定的比例添加到面条中。对面条的蒸煮性质、质地、感官等各个指标进行分析,研究玉米抗性淀粉的添加量对面条品质的影响。结果表明：随着玉米抗性淀粉的增加,面条的弯曲断条率逐渐增加, 吸水率逐渐降低,蒸煮损失逐渐升高;面条的硬度和黏着性明显降低,弹性没有显著性差异,但趋势是降低的,黏聚性逐渐下降,胶着性和咀嚼度显著降低,回复性逐渐下降;面条的总体感官评价逐渐降低,但差异不显著。     

玉米抗性淀粉的添加对面条品质的影响北大核心

以普通玉米淀粉为原料,经高温高压蒸煮、冷却、回生后,制备RS3型玉米抗性淀粉,按一定的比例添加到面条中。对面条的蒸煮性质、质地、感官等各个指标进行分析,研究玉米抗性淀粉的添加量对面条品质的影响。结果表明:随着玉米抗性淀粉的增加,面条的弯曲断条率逐渐增加,吸水率逐渐降低,蒸煮损失逐渐升高;面条的硬度和黏着性明显降低,弹性没有显著性差异,但趋势是降低的,黏聚性逐渐下降,胶着性和咀嚼度显著降低,回复性逐渐下降;面条的总体感官评价逐渐降低,但差异不显著。     

抗性淀粉对面粉品质及面团流变学特性影响研究

探讨抗性淀粉对小麦粉流变学特性的影响。分别考察了其对高筋粉、中筋粉的粉质特性、拉伸特性和糊化粘度特性的影响,结果表明,抗性淀粉的添加在一定程度上影响了小麦粉的流变学指标和面粉品质。具体表现为面团稳定时间和粉质评价值降低,弱化度增加,延伸度与拉伸曲线面积降低。抗性淀粉的添加使高筋粉的糊化温程升高,糊化时间延长,对中筋粉的糊化温程和时间影响较小。     

谷朊粉和小麦淀粉添加量对重组面团冻藏品质的影响

面团的冷冻保存品质无法满足鲜湿面条工业化生产的要求。为了研究面团主要组分（面筋蛋白和淀粉）对面团冷冻品质的影响,以高筋小麦面粉（50%）、谷朊粉和小麦淀粉（不同比例）为原料进行面团重组,-18℃冻藏20 d分析其水分分布、流变特性、糊化特性、凝胶强度、微观结构以及氢键强度,以100%原小麦面粉作为对照组。结果表明,随着谷朊粉:小麦淀粉比例从4:1减小至1:4,冷冻重组面团中的水分分布逐渐由结合水向自由水迁移,弹性模量从125900 Pa降低至73020 Pa;样品的各项糊化参数增大,凝胶硬度也由114.30 g增大到181.39 g。扫描电镜观察发现,谷朊粉:小麦淀粉比例越低越不利于面筋蛋白网络结构的均匀性。添加了谷朊粉和小麦淀粉后,重组面团中的氢键强度均大于对照组,且随着谷朊粉:小麦淀粉比例的减小不断增大。当谷朊粉:小麦淀粉为4:1时,冻藏20 d的重组面团的弹性模量值比对照组高49.95%,有效延缓了面团在冻藏过程中的品质劣变。将淀粉与面筋蛋白进行面团重组可以提高面团的黏弹性,进而有利于其冷冻保存品质。     

Physicochemical and functional properties of Caryota urens flour as compared to wheat flour

Starch digestibility, thermal, pasting and gelling properties of Caryota urens (CU) flour were investigated using wheat flour as reference. Amylose content of CU and wheat flour was 32.1% and 28.3%, respectively. CU flour had very low content of protein and lipid but had a high content of total starch (98.2%) and resistant starch (RS) [42.5%]. Gelatinisation temperature (78.5 °C) of CU flour was higher than wheat flour. Pasting behaviour of CU flour was similar to that of high swelling tuber and root and waxy starches. CU flour retrograded to a greater extent than wheat flour. Very specific gelling behaviour was noticed for CU flour where it produced significantly harder gel with high paste clarity, fracture ability, adhesiveness, gumminess and chewiness. Expected glycaemic index (eGI) of CU and wheat flour was 92.4 and 100.4, respectively. CU flour had high eGI despite high content of resistant starch.     

Effect of green plantain flour addition to gluten‐free bread on functional bread properties and resistant starch content

Green plantain flour (GPF) was used as a functional ingredient to produce gluten‐free (GF) bread based on a flour blend of rice flour and GF wheat starch (50:50) to improve their functional properties and to increase their resistant starch (RS) content. In pretrials, an addition of up to 30% GPF provided acceptable bread quality with maximum RS content. Based on these trials, two 2³ factorial screening experimental designs were applied, where water content, baking temperature and baking time of GF bread containing 30% GPF addition were optimised. The best baking conditions to achieve satisfying GF bread quality – higher loaf volume, softer crumb firmness and regular porosity structure at the highest RS content could be defined to a maximum addition of water at 160%, baking temperature of 180 °C and baking time of 90 min. The incorporation of GPF showed good potential to improve the quality of GF bread.     

Effects of plasma-activated water and heat moisture treatment on the properties of wheat flour and dough

Plasma-activated water (PAW) production and use is an emerging technology for enhancing product safety, extending shelf-life and quality retention, and promoting sustainable processing. At present, it has generated considerable attention for applications to starch and flour modification. This work presents an innovative approach to wheat flour (WF) modification using PAW and heat-moisture treatment (HMT), and compares this approach with distilled water (DW) treatment. As expected, PAW and HMT promoted flour granule clustering, increasing particle size. These treatments accelerated molecular interactions between wheat starch and non-starch components (e.g. proteins and lipids), which eventually increased resistant starch (RS) content. Addition of modified flour (30 g) to WF positively affected its rheological properties, and closely bound water content of the dough. The gluten protein network structure in the dough suffered varying degrees of damage. In conclusion, our results showed that PAW and HMT may provide a novel beneficial method for modifying wheat flour during food processing to obtain viscoelastic wheat flour products with nutritional functions.     

基于模糊数学感官评价研制凉皮专用小麦粉

以中筋小麦石优17分别与三种强筋小麦（藁优2018、师栾02-1、冀麦323）按不同比例配麦，采用传统洗面方法蒸制鲜凉皮和面筋，测定质构、感官、出品率和淀粉沉降速度，利用模糊数学综合评价法将感官数据分数化。对最佳配比小麦粉进行面筋质量、糊化和流变学特性分析。结果表明：与市售凉皮粉及石优17相比，30%师栾02-1综合评价最好，其沉降速度最快，4 h淀粉浆液体积为182.5 mL，且凉皮和面筋弹性数据最大值分别为1.17和1.84 mm，凉皮感官品质仅次于市售凉皮粉，面筋感官评分也较好。凉皮和面筋出品率较市售凉皮粉分别提高了3.64%和2.38%。面筋指数、稳定时间、粉质质量指数、拉伸曲线面积、最大拉伸阻力、最大拉伸比例显著提高，吸水率、弱化度、崩解值较配麦前显著减小。     

Enhancement of Resistant Starch (RS3) in Amylomaize,Barley, Field Pea and Lentil Starches

Native starches isolated from amylomaize. Glacier high amylose barley, field peas and lentils contained 3–5% (w/w) resistant starch (RS3). Retrograded gels that were prepared from these starches had higher RS3 (6–9%) contents. The effects of gel concentration (% starch), storage temperature and time on the RS3 content of the retrograded gels were investigated; the optimum RS3 content was determined in gels prepared at = 10% (w/v) starch concentration and stored under = 20°C for = 5 days. Annealing of the retrograded starch gels by heating and cooling cycles, further enhanced RS3 content to 9–19%; the effect of annealing temperature and number of heat-cool cycles on the RS3 content of the annealed gel were studied. The hydrolysis of retrograded starch gels by pulanase enzyme or acid (2.2 N HCl), prior to annealing, enhanced the RS3 formation during annealing; the enzyme or acid treatment increased RS3 content of the annealed gel to 15–24% or 17–24%, respectively. The potential molecular mechanism that is responsible for the RS3 increase is discussed.     

Influence of gluten on the viscoelastic properties of starch pastes and gels

Viscoelastic properties of dispersions (60–300 g kg⁻¹) of gluten (G) and wheat starch (S) blends (0 < G/S < 0·20) and wheat flour have been studied during heating and cooling. In both cases, the moduli followed power law relationships with concentration. The temperature at which the transient network development began, caused by granule–granule interactions, decreased as the concentration increased and increased with an increase in the proportion of gluten. Moreover, gluten weakened the strength of both starch pastes and gels, as shown by the lower values of the moduli. The viscoelastic behaviour of flour samples reflected the role played by internal lipids. A structural model is proposed in order to explain the influence of gluten on the rheological behaviour of starch pastes and gels. © 1998 Society of Chemical Industry.     

Flow Behavior of Mixed-Protein Incipient Gels

Strong protein gel networks may result from synergistic interactions with other proteins or food materials above that are not achievable with a single protein alone. The varying flow and viscoelastic behavior of calcium caseinate or whey protein isolate mixed with egg albumin, fish protein isolate, soy protein isolate, or wheat gluten in a model system with wheat flour and glycerol as starch and oil surrogates was determined. Temperature sweeps revealed peak tan δ values as the proteins aggregated. Single protein gels of calcium caseinate, soy protein isolate, and wheat gluten were predominantly elastic, while egg albumin and whey protein isolate gels were mostly viscous. For example, egg albumin steady shear viscosities were: 0.0145 Pa s (0.5 min) and 0.1331 Pa s (45 min), and whey protein isolate 0.0003 Pa s (0.5 min) and 0.0024 Pa s (45 min); but combined with whey protein isolate (whey protein isolate/egg albumin: 10/5 wt%), the apparent viscosity values dropped to 0.0053 Pa.s (0.5 min) and 0.0221 Pa s (45 min), respectively.     

Effects of ball‐milling on the glass transition of wheat flour constituents

BACKGROUND: Starch and gluten, the major components of wheat flour, greatly influence the structural characteristics of food products made with wheat flour. The effects of ball‐milling on the change in the semicrystalline structure of starch granules to the amorphous state have been reported. However, the effects of ball‐milling of native wheat flour on physicochemical changes in wheat flour constituents have not been elucidated. Therefore in this study the effects of ball‐milling on the glass transition of wheat flour constituents were investigated. RESULTS: Crude gluten, non‐gluten proteins and separated starch were obtained from wheat flour ball‐milled for 0–10 h, and the glass transition temperature (T_g) of these constituents was evaluated. The T_g of all wheat flour constituents decreased with increasing ball‐milling time. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that changes in band position and intensity did not occur for gluten but did occur for non‐gluten proteins. X‐ray diffraction revealed decreased crystallinity and greater plasticisation by water in separated starch as the ball‐milling time was prolonged. CONCLUSION: The results showed that the ball‐milling process decreased the T_g of wheat flour constituents as a function of milling time. The decrease in T_g was probably due to changes in conformation of protein subunits in gluten and depolymerisation of the non‐gluten protein fraction. The information obtained here about the physical alteration of wheat flour constituents may enhance the ability to successfully use ball‐milled wheat flour in food applications. Copyright © 2008 Society of Chemical Industry