预糊化变性淀粉在麻糬面包中的应用

本文研究了预糊化木薯变性淀粉、预糊化马铃薯变性淀粉、预糊化玉米变性淀粉和预糊化大米粉对麻糬面包的感官评价、比容、弹性的影响,分析了预糊化变性淀粉的布拉班德粘度曲线,结果表明,预糊化木薯变性淀粉与预糊化马铃薯变性淀粉制作的麻糬面包口感及外观较好,而预糊化玉米变性淀粉与预糊化大米粉制作的产品口感不佳、比容小,预糊化木薯变性淀粉与预糊化马铃薯变性淀粉质量比为1:1时,麻糬面包加工性能好、口感清爽、弹性强、比容较大、保型性佳。     

淀粉糊化工艺的研究

运用Brabender糊化仪研究了玉米淀粉的糊化特性,比较了玉米淀粉和大米淀粉的糊化特性差异．结合玉米淀粉的糊化特性,研究了糊化料水比、耐高温仅一淀粉酶添加量、耐高温α-淀粉酶的品种等因素对玉米淀粉糊化、液化效果的影响。根据玉米淀粉的糊化性质,优化确定了玉米淀粉的糊化工艺,在大生产中进行了验证和对比。     

不同变性淀粉对麻糬面包品质的影响

为了探索并优化麻糬面包的配方,研究了预糊化乙酰化双淀粉己二酸酯分别与羟丙基二淀粉磷酸酯、乙酰化双淀粉和磷酸酯双淀粉的不同复配比例对麻糬面团的流变特性、微观结构,以及麻糬面包的比容、感官评价与质构特性的影响。结果表明,随着预糊化淀粉添加量的增加,麻糬面包的储能模量与损耗模量升高,初始模量最高分别超过12 500 Pa和4 000 Pa。羟丙基变性淀粉与磷酸酯变性淀粉组中预糊化淀粉添加量增加,麻糬面包的硬度升高到7 571.47 g和6 017.17 g,咀嚼度升高到2 435.48和2 840.05,但是比容逐渐降低,微观结构变的更清晰。而乙酰化变性淀粉组中预糊化淀粉含量升高,麻糬面包的硬度与咀嚼性先下降后上升,比容先上升后下降。当预糊化淀粉添加量为20%时,麻糬面包的感官评分最高,达到86.25分。该研究结果可为麻糬面包的原料提供更多选择,为其加工提供理论依据。     

不同类型玉米灌浆期淀粉的热力学和晶体特性

以普通玉米、糯玉米、爆裂玉米和甜玉米为材料,采用差示扫描量热仪(DSC)和X-射线衍射仪分析玉米籽粒灌浆过程中淀粉热力学特性和晶体特性的变化趋势和差异。结果表明,随着籽粒灌浆,DSC糊化峰向低温方向移动,峰宽增大,峰值、糊化温度、热焓及结晶度呈逐渐降低趋势。说明与籽粒灌浆后期相比,灌浆前期的玉米淀粉较难糊化。类型间比较,糯玉米和甜玉米分别具有最大和最小的热焓。说明糯玉米淀粉难以糊化,甜玉米淀粉容易糊化。     

酯化蜡质玉米淀粉对糯米粉团冷冻特性的影响

目的评价酯化蜡质玉米淀粉和预糊化酯化蜡质玉米淀粉对糯米粉团冷冻特性的影响。方法测定酯化蜡质玉米淀粉与预糊化酯化蜡质玉米淀粉的冻融稳定性;分别往糯米粉中添加1%、2%、3%、4%(m:m)4个比例的酯化蜡质玉米淀粉和预糊化酯化蜡质玉米淀粉制作速冻糯米粉团,检测速冻糯米粉团的失水率、裂口率、煮熟时间、糊汤率、感官评价等指标。结果预糊化酯化蜡质玉米淀粉与酯化蜡质玉米淀粉均具有良好的冻融稳定性,能有效降低速冻糯米粉团的失水率和裂口率,同时改善速冻糯米粉团的蒸煮和食味品质;预糊化酯化蜡质玉米淀粉在改善糯米粉团冷冻特性斱面效果更优,但两者差距不大,当预糊化酯化蜡质玉米淀粉的添加量为1%时,速冻糯米粉团的失水率为11.8%,裂口率为22.5%,煮熟时间为229 s,吸光度为0.823,感官及外观评分分别为79.3分、23.1分。结论添加1%预糊化酯化蜡质玉米淀粉制成的糯米粉团冷冻特性最好。     

亚糊化热处理对玉米淀粉-胡椒碱复合物功能特性的影响

为探究在亚糊化温度下胡椒碱负载于玉米淀粉对其结构和理化特性的影响,本研究选用玉米淀粉在60℃下制备亚糊化玉米淀粉-胡椒碱复合物,并通过扫描电镜、快速糊化粘度测定仪、差示扫描量热、傅里叶变换红外光谱和X射线衍射等进行了表征。结果表明,胡椒碱成功负载到亚糊化玉米淀粉上,负载率为39.45%;扫描电镜结果显示淀粉颗粒膨胀的裂隙内部成功负载胡椒碱,粒径从天然玉米淀粉的15.20μm增大到亚糊化玉米淀粉的25.80μm,再到亚糊化玉米淀粉-胡椒碱复合物的81.90μm;胡椒碱的加入降低了亚糊化玉米淀粉的峰值粘度和谷值粘度;复合物红外光谱未产生新的基团或化学键,但胡椒碱的加入增强了玉米淀粉与胡椒碱的分子内和分子间氢键作用;X-射线衍射表明相对结晶度从天然玉米淀粉的23.52%升高到亚糊化玉米淀粉-胡椒碱复合物的28.15%,但是亚糊化处理未改变玉米淀粉的晶型结构;与天然玉米淀粉相比,亚糊化玉米淀粉和亚糊化玉米淀粉-胡椒碱复合物的凝胶焓值显著（P<0.05）降低。亚糊化玉米淀粉负载胡椒碱,胡椒碱的加入对亚糊化玉米淀粉的结构影响较小,但对其理化性质产生了显著的影响,并为淀粉与胡椒碱之间的相互作用...     

茶多酚对小麦淀粉理化特性和面包品质的影响及机理

目的：研究茶多酚对小麦淀粉理化特性和面包品质的影响及机理。方法：分析茶多酚对小麦淀粉透光率、糊化特性、老化特性及微观结构等理化特性的影响;分析茶多酚对面包的比容、质构和颜色等品质指标的影响;采用分子动力学模拟技术,探究茶多酚与小麦淀粉的分子相互作用机理。结果：茶多酚可降低淀粉糊的透光率,促进淀粉的糊化,抑制淀粉的老化,改变淀粉凝胶的微观结构;不同添加量的茶多酚对面包的比容、质构及颜色影响差异明显;茶多酚通过影响分子内氢键与分子间氢键的形成而改变淀粉分子的空间构型,表没食子儿茶素没食子酸酯与淀粉分子的结合更稳定,氢键比例更高,结合自由能更低。结论：茶多酚具有改良小麦淀粉理化特性及面包品质的潜力。     

魔芋胶和玉米淀粉混合物黏弹特性的研究

目的 研究魔芋胶对玉米淀粉黏弹特性的影响。方法 以玉米淀粉为原料, 加入不同比例的魔芋胶, 采用动态流变仪来研究魔芋胶玉米淀粉糊化混合物的黏弹特性。结果 Power-Low模型能够有效地表征魔芋胶玉米淀粉糊化混合物的流变性能。魔芋胶玉米淀粉糊化混合物为假塑性流体, 与单独的玉米淀粉糊相比, 随着魔芋胶的添加量增大, 糊化混合物黏稠性增大, 假塑性增强。随着频率的增大, G?和G?均增大, 损失正切值tan δ＜1, 说明魔芋胶的加入使得糊化混合物具有优越的黏弹性。结论 当魔芋胶/玉米淀粉质量比为0.4:0.8时, 糊化混合物弹性最小, 黏性最大, 糊化混合具有更好的协同增稠作用, 即糊化混合物流体流动特征显著。     

低压等离子体处理对蜡质玉米淀粉性质的影响

采用低压等离子体对蜡质玉米淀粉进行改性。在等离子体处理时间为4 min,处理功率分别为100、200、300、400 W时,研究了蜡质玉米淀粉的红外光谱特性、交联度、糊化特性和流变学性质。实验结果表明:等离子体处理使蜡质玉米淀粉发生了交联反应,淀粉的储能模量增加,损耗模量基本不变,能形成弱凝胶;糊化难度增加,糊化温度升高。     

变性淀粉对冷冻面团面包品质的影响

以木薯淀粉为原料,主要研究了预糊化淀粉、羟丙基二淀粉磷酸酯和乙酰化二淀粉磷酸酯三种变性淀粉的物化特性与冻融稳定性,以及它们对冷冻面团面包比容及面包全质构的影响。实验结果表明:木薯淀粉经过不同方式的变性后,物化特性差异很大,其中,羟丙基二淀粉磷酸酯的冻融稳定性最好,预糊化淀粉的冻融稳定性最差;添加5%三种变性淀粉后均能显著延缓冷冻面团的下降趋势,并对冷冻面团面包的品质具有良好的改善作用。这一结果与变性淀粉冻融稳定性及冷冻面团面包比容变化趋势一致,进一步表明变性淀粉,尤其是羟丙基二淀粉磷酸酯可以有效抑制冷冻面团内部水分的迁移,降低冻藏过程中冰晶和重结晶的形成,从而改善冷冻面团面包的内部质构。     

Physicochemical Properties and Consumer Acceptance of Wheat-Germinated Brown Rice Bread during Storage Time

Abstract: Selected physicochemical properties and consumer acceptance of bread prepared from composite flour (wheat:germinated brown rice:germinated glutinous brown rice flours at 60:30:10 ratio) were evaluated during storage for 0, 3, and 5 d, and compared with wheat bread (0 d, control). During storage, color profiles and water activity (from 0.947 to 0.932) of crumbs of composite flour breads slightly changed, but moisture content drastically decreased along with increasing crumb hardness (from 4.16 N to 10.37 N). Higher retrogradation in bread crumb was observed particularly for 5-d stored bread (ΔH = 2.24 J/g) compared to that of the fresh composite bread and the control (ΔH = 0.70 and 0.51 J/g, respectively). Mean (n = 116) overall liking score of the fresh composite flour bread (0 d) was slightly lower than that of the control (7.1 compared with 7.6 based on a 9-point hedonic scale). At least 76% of consumers would purchase the fresh composite flour bread if commercially available. Breads were differentiated by textural (moistness, smoothness, and softness) acceptability with canonical correlation of 0.84 to 0.87. The signal-to-noise ratio values of the 5-d stored breads were lower than the control, due mainly to the non-JAR (not-enough) intensity responses for moistness, smoothness, and softness; the mean drop of liking scores for these attributes ranged from 2.42 to 2.98. Flavor acceptability and overall liking were factors influencing consumers’ purchase intent of composite flour breads based on logistic regression analysis. This study demonstrated feasibility of incorporating up to 40% germinated brown rice flour in a wheat bread formulation. Practical Application: Our previous study revealed that flours from germinated brown rice have better nutritional properties, particularly gamma-aminobutyric acid (GABA), than the nongerminated one. This study demonstrated feasibility of incorporating up to 40% germinated brown rice flour in a wheat bread formulation. In the current U.S. market, this type of bread may be sold as frozen bread that would have a longer shelf life, or may be supplied as a food-service product that would be made-to-order or made fresh daily as currently practiced in some major grocery stores.     

Effect of Soybean 7S Protein Fractions, Obtained from Germinated and Nongerminated Seeds, on Dough Rheological Properties and Bread Quality

Germinated soybean flour has been proposed for use in bread making as a product to improve bread quality when small amounts are added to wheat flour. However, it is not clear which soybean components promote this action, and how these components may influence bread quality. The aim of this work was to evaluate the effect of the addition of soybean 7S protein fraction obtained from germinated and nongerminated seeds in dough rheological properties (farinographic and extensographic) and bread quality, including loaf volume, texture (firmness, compression force, resilience), colour (L*, a*, b*), crumb grain structure (cell density, mean cell area, shape factor), and consumer acceptance (sensory analysis). Results showed that this protein fraction just slightly affects bread quality, since no significant changes (P > 0.05) on bread volume and texture were obtained. Only crust and crumb colour were affected in a small amount, and a coarser crumb structure was also observed when adding 7S protein obtained from germinated soybean at its highest concentration. As the proportion of protein increased in the flour, both kinds of 7S fraction (germinated and nongerminated) were related to the increment in water absorption, as well as to the increment in extensographic maximum resistance to extension, specifically when adding 7S protein obtained from nongerminated soybean seeds. These results showed that the 7S soybean protein, as obtained in this work, is not related to the reported loaf bread quality improving effect of this legume when it is added in small quantities.     

Optimization of Gluten-Free Bread Prepared from Cornstarch, Rice Flour, and Cassava Starch

ABSTRACT: The proportions of cornstarch, cassava starch, and rice flour were optimized for production of gluten-free bread (with 0% and 0.5% soy flour) to maximize specific volume (Y₁,Y₁'), crumb-grain score (Y₂,Y₂'), and bread score (Y₃,Y₃'). A central composite design involving cornstarch/cassava starch ratio (X₁) and rice flour/cassava starch ratio (X₂) was used, and 2nd-order models for Y₁ and Y₁' were employed to generate response surfaces. The maxima of response surfaces for crumb-grain score and bread score indicate that optimal gluten-free bread can be prepared from 74.2% cornstarch, 17.2% rice flour, and 8.6% cassava starch. Addition of soy flour at the 0.5% level also improved bread texture.     

木聚糖酶对面粉糊化特性和面包品质的影响

探讨不同添加量的木聚糖酶对面粉的糊化特性、面包焙烤品质以及面包贮存品质的影响.结果表明:添加木聚糖酶对面粉的糊化温度、衰减值、回生值影响不大,但可降低面粉的峰值黏度、最低黏度和最终黏度,木聚糖酶能有效地改善面包焙烤品质,显著增加面包比容,有效改善面包的硬度和弹性,明显的降低了面包的老化程度.当木聚糖酶添加量为10 mL/kg面粉时,面包焙烤品质及贮存效果最佳.     

豌豆全粉对小麦面团特性和面包品质的影响

探讨了萌芽程度不同的豌豆全粉(添加量均为5%)对小麦面团加工特性(水分分布、黏性、发酵流变特性、动态流变特性)及面包品质(面包芯质构、面包贮藏期硬度等)的影响。结果表明:与小麦面团(WD)相比,添加未萌芽豌豆全粉(G0MD)的面团中不易流动水的比例升高,结合水和自由水的比例降低,面团发酵产气量降低,面团储能模量(G′),损耗模量(G″)显著下降,面包在储藏期内(1～7 d)面包的硬度增加缓慢。与G0MD相比,添加萌芽豌豆全粉的面团中结合水比例增加,不易流动水比例降低,黏性显著降低,G′、G″均增加,面包老化速度变慢。因此,将萌芽豌豆全粉用于面包的制作表现出良好的应用前景。     

添加发芽小麦对小麦粉及制品品质影响

在小麦中添加不同比例的发芽小麦,研究对小麦、小麦粉品质特性及食用品质的影响。选择发芽小麦按照不同比例(1%、5%、10%、15%、20%、25%、30%)与正常小麦进行混合,研究发芽小麦不同添加比例对小麦及小麦粉品质特性产生的影响,并对不同添加比例发芽小麦粉制作的馒头和面条食用品质进行评价。结果表明:随着发芽小麦比例含量的增加,混合小麦及小麦粉品质特性指标中除降落数值逐渐减少,其他特性指标与正常小麦相比较无明显变化。对馒头和面条进行蒸煮实验评价,可以看出当发芽小麦含量不超过15%时,对其食用品质无明显影响,但当发芽小麦含量超过20%时,馒头出现粘牙,当发芽小麦含量超过15%时,面条韧性下降,食用品质受到影响,评分值均在80分以下。     

Effect of Initial Baking and Storage Time on Pasting Properties and Aging of Par-Baked and Rebaked Rye Bread

Part-baked rye bread with and without Ca-propionate (0.2 g/100 flour) were baked for 10, 15, 20 minutes at 230°C and stored at refrigerator temperature (4°C) for 10, 20, 30 days then second-baked for 5, 10, 15 minutes at the same temperature to give an oven-fresh end product. The effect of antimicrobial additive (Ca-propionate), part-baking, storage in refrigerator and rebaking on quality parameters such as yield of volume and crumb softness, water activity and pasting properties of rye bread crumb was evaluated. Addition of Ca-propionate increased bump area, while yield of volume and softness values of rye bread crumb decreased. The increase in initial baking time caused a decrease in the pasting temperature, water activity, and softness value and an increase in the bump area and viscosity of the rebaked bread crumb. Bump area and pasting temperature of rebaked rye bread crumb increased with longer (intermediate storage) time, while viscosity, yield of volume, water activity, and softness values decreased. A strong negative correlation was observed between pasting temperature and other parameters, which are bump area, peak viscosity, holding end viscosity, cooling end viscosity, and softness value for rye bread that was rebaked after part-baked and storing at refrigerator temperature. The re-baking rye bread after part-baking for 10 and 15 minutes and storage for 7, 14, and 21 days at refrigerator temperature gave softer crumb than the control group.     

Exploring the applicability of tamarind gum for making gluten-free rice bread

The present study explored the applicability of tamarind gum in making gluten-free rice bread. Hydration properties of gums and pasting properties of rice flour with the gums were analyzed with Rapid ViscoAnalyzer. Batter properties and bread quality characteristics of rice bread containing gums were analyzed. Except for guar and xanthan gum, the final viscosity after hydration of other gums and the pasting properties of rice flour with the gums were similar. The batter properties and the quality of rice bread containing tamarind gum were equivalent or superior to those containing other gums. Cross-sections of rice bread showed that addition of tamarind gum and pectin resulted in a fine appearance, but pectin may not be preferred due to its lower pH causing unpleasant sour taste and smell of the rice bread containing the gum. Therefore, tamarind gum can be a useful gum for applying to make gluten-free rice bread.     

发芽糙米粉面团性质及面包品质研究

将未发芽和发芽12、24、36、48 h的糙米磨粉,分别与20%的谷朊粉混合制作面团和面包,研究了发芽糙米-谷朊粉面团流变性质及面包品质。结果表明,随着发芽时间的增加,糙米面团弹性模量和粘性模量均降低。扫描电镜结果显示,发芽12 h和24 h糙米面团形成均匀致密的网络结构,发芽24 h后,网络结构部分破裂。随着发芽时间的延长,糙米面包比容、弹性、回复性降低,硬度先降低后升高。发芽12 h和24 h,糙米面包硬度较低,比容、弹性和回复性较大。发芽12 h的糙米面包感官评分最高。因此,发芽12 h时的糙米面包品质最好。     

发芽糙米营养成分及淀粉糊化特性研究

以3个粳稻和2个糯稻为原料,制备发芽糙米,分析了糙米发芽前后游离氨基酸、蛋白质、水溶性糖类、脂肪酸值以及Mixolab淀粉糊化特性的变化。结果表明,与糙米相比,发芽糙米游离氨基酸总量、水溶性总糖、还原糖及果胶酸含量显著增加。Mixolab混合仪测定的发芽糙米米粉团蛋白质结构严重弱化,淀粉糊化能力显著降低。油酸含量和脂肪酸值均增加。发芽糯糙米水溶性总糖、还原糖及果胶酸含量显著高于发芽粳糙米,破损淀粉含量显著低于发芽粳糙米。