混合粉组成与米发糕品质特性相关性研究

为制得良好品质的米发糕,通过将高筋小麦粉与大米粉混合,并调整混合粉中大米粉与蛋白质的比例,分析了混合粉特性、面团粉质特性及米发糕质构特性之间的相关性。结果表明,混合粉中蛋白质含量与比容呈显著正相关,与咀嚼性呈显著负相关;支链淀粉含量对米发糕影响较大,与咀嚼性呈显著正相关;当混合粉中大米粉含量为70%时,米发糕的比容最大,质构特性较佳。本文可为米发糕后续实验提供理论依据。     

乳化剂改善无麸质面包焙烤特性的研究

研究了乳化剂对无麸质面包(米粉、红薯淀粉)比容、硬度、色泽及感官品质的影响。结果表明,添加硬脂酰乳酸钠、蔗糖脂肪酸酯、大豆卵磷脂、分子蒸馏单甘酯可改善无麸质面包的品质,面包比容增大,结构松软,气孔更加均匀,硬度降低,色泽改善,感官品质提高。综合来看,添加0.5g/100g的分子蒸馏单甘酯无麸质面包品质改善最为明显,比容增加16.9%,硬度降低46.9%(24h),面包色泽明显改善,感官品质最好。     

大豆分离蛋白提升鲜湿米粉凝胶品质的研究

为探究大豆分离蛋白(Soy Protein Isolate, SPI)对鲜湿米粉凝胶品质的影响,将SPI以0%、2%、4%质量浓度比例与发酵籼米粉混合,对SPI-发酵籼米混合粉的性质及所制SPI-鲜湿米粉的凝胶品质进行测定,并分析了SPI-鲜湿米粉内部淀粉结构的变化。结果表明：随着SPI添加量的增加,SPI-发酵籼米混合粉的糊化黏度增大,崩解值减小,凝胶硬度增大,推断SPI的添加有利于发酵籼米淀粉的凝胶化;进一步测定发现,SPI-鲜湿米粉的硬度、咀嚼性、胶黏性增大,蒸煮吸水率上升,说明添加SPI可提升鲜湿米粉凝胶品质;FT-IR显示,R104 7/102 2 cm-1峰强度比值增大、R102 2/995 cm-1峰强度比值减小,两者比值表示鲜湿米粉内部淀粉短程有序结构和氢键强度增加,即淀粉短程有序性升高,这可能与鲜湿米粉凝胶品质的提升相关。     

冷冻猪肉丸中大豆分离蛋白结构变化及共存物对其功能性的影响研究

目的研究冷冻条件(–18℃, 2 d)下大豆分离蛋白(soybean protein isolate, SPI)结构变化以及猪肉丸中共存物(猪脂肪、SPI替代瘦肉量、淀粉和食盐)对SPI功能特性的影响。方法采用巯基、二硫键含量及表面疏水性分析冷冻条件对SPI结构影响,通过保水性、保油性及乳化特性变化研究冷冻条件猪肉丸中共存物对SPI功能特性的影响。结果冷冻处理后SPI游离巯基含量下降0.75μmol/g,暴露巯基、二硫键含量分别增加了1.83、6.45μmol/g,表面疏水性由192.76增至699.93。添加10%猪脂肪、15%SPI替代瘦肉量、20%淀粉和2%食盐, SPI共存体系获得最佳保水性、保油性,分别添加30%猪脂肪、15%SPI替代瘦肉量、15%淀粉和2%食盐, SPI共存体系获得最佳乳化特性。结论冷冻条件对SPI结构变化影响显著,且猪肉丸中SPI共存物含量影响共存体系的保水性、保油性及乳化特性;为SPI在冷冻肉制品中应用提供参考依据。     

大豆分离蛋白对肌原纤维蛋白加热过程中结构及流变特性的影响

大豆分离蛋白（soybean protein isolate,SPI）作为优质的植物蛋白常被用于肉制品加工中,以提高产品产量和质地。研究添加SPI对肌原纤维蛋白（myofibrillar protein,MP）凝胶特性及MP加热过程中结构和流变特性的影响。结果表明：添加10%、20% SPI能提升混合凝胶的凝胶强度及保水性（P＜0.05）;加热过程中混合蛋白凝胶二级结构发生改变,但其变化规律尚不明确;添加SPI使混合凝胶储能模量及损耗模量下降;混合凝胶上清液十二烷基硫酸钠-聚丙烯酰胺凝胶电泳图谱显示,肌球蛋白重链、肌动蛋白、SPI部分亚基均是参与凝胶形成的蛋白质。     

超声预处理对大豆分离蛋白-儿茶素非共价/共价复合物结构及功能的影响

目的:探究超声预处理对大豆分离蛋白(soybean protein isolate,SPI)-儿茶素非共价/共价复合物结构及功能的影响.方法:对SPI进行超声处理后,在不同pH值(3.0、7.0、9.0、12.0)下与儿茶素通过非共价/共价结合方式制备复合物,并通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium do...     

不同外源蛋白对小龙虾丸品质的影响

研究小麦面筋蛋白（wheat gluten proteins,WG）、大豆分离蛋白（soybean protein isolate,SPI）和花生分离蛋白（peanut protein isolate,PPI）的添加对小龙虾丸品质的影响。利用质构仪、色差计、低场核磁共振仪等对添加3 种不同外源蛋白小龙虾丸的感官评分、凝胶特性、持水性、蒸煮损失率、白度和横向弛豫时间T2进行测定,并用Pearson法对各指标进行相关性分析。结果表明：不同添加量的3 种非肌肉蛋白均能够改善小龙虾丸凝胶特性,提高保水性,降低蒸煮损失率,改善小龙虾丸内部空间三维网络结构,降低白度,各指标之间相关性显著（P＜0.05）;相比于SPI和PPI,添加WG对小龙虾丸品质的改善最为明显,WG添加量为6%时,小龙虾丸的凝胶强度、保水性比对照组分别增加64.8%和11.3%;小龙虾丸白度随着外源蛋白添加量的增加而降低,其中WG能有效降低对小龙虾丸白度的影响,与SPI和PPI组差异显著（P＜0.05）;PPI添加量2%时,小龙虾丸感官评分和凝胶特性优于WG和SPI组。整体而言,选用添加量6%的WG更能有效提高小龙虾丸品质及消费者可接受度。     

莲子淀粉重组米制备工艺优化

以不同比例莲子淀粉与碎米粉进行混合后挤压制备重组米,通过对混合粉的糊化特性和重组米的感官品质、质构特性及蒸煮损失率的分析,确定了莲子淀粉重组米的配比。以物料含水量、模头温度、螺杆转速为影响因素,采用响应面试验优化了莲子淀粉重组米挤压的最佳工艺条件。结果表明:随着莲子淀粉添加量的增加,混合粉的峰值黏度、谷值黏度、崩解值、最终黏度及回生值等均逐渐增加;感官评分先增大后减小,在莲子淀粉添加量为30%时较高;质构特性中硬度逐渐增大,弹性、咀嚼性、黏聚性先增大后减小,在莲子淀粉添加量为30%时最大;蒸煮损失率逐渐增大。综合分析,重组米品质在莲子淀粉添加量为30%时达到最佳。重组米的最佳挤压条件为:物料含水量40%、螺杆转速210 r/min、模头温度95 ℃时,重组米评分为69.13分。     

基于美拉德反应的大豆分离蛋白改性膜的制备及应用研究

目的 采用美拉德反应（Maillard reaction，MR）提高大豆分离蛋白（soybean protein isolate，SPI）膜的性能，并实现对水产品的保鲜效果。方法 研究了还原糖种类、SPI/核糖比例、pH、温度和时间对SPI改性（soybean protein isolate modified，SPIM）膜水溶性的影响，以及MR对SPIM膜外观色泽、微观结构和机械性能的影响；制备负载ε-聚赖氨酸盐酸盐（ε-PL）的SPIM抗菌（soybean protein isolate modified antibacterial，SPIMA）膜并用于包装南美白对虾虾仁，通过挥发性盐基氮（total volatile base nitrogen，TVB-N）和菌落总数（total bacterial count，TBC）初步评价其保鲜效果。结果 确定了MR条件为SPI/核糖比例40:1、膜液初始pH 10、50°C下加热反应2 h，获得了水溶性、外观色泽、微观结构和机械性能等综合表现较优的SPIM膜；当ε-PL添加量为0.8%时，SPIMA膜对大肠杆菌和金黄色葡萄球菌表现出显著的抗菌活性；应用结果表明，SPIMA膜有效抑制南美白对虾虾仁贮藏期间TBC和TVB-N含量的上升。结论 MR改善了SPI膜的耐水性和机械性能，使其有效负载ε-PL并延缓南美白对虾虾仁贮藏期间的腐败变质，为SPI基膜在高水分含量食品中的应用提供技术支撑。     

马铃薯全粉-碎米混合粉的糊化特性及其挤压重组米品质

将马铃薯全粉与碎米按不同比例混合,测定混合粉的糊化特性及其挤压重组米的感官品质、质构特性和蒸煮损失率,探讨马铃薯全粉添加量对混合粉糊化特性及其挤压重组米品质的影响。结果表明:随着马铃薯全粉添加量的增加,马铃薯全粉-碎米混合粉的峰值黏度、谷值黏度、最终黏度、衰减值和回生值均逐渐减小;马铃薯挤压重组米的感官评分先增大后减小,在添加量为40%~50%时较高;质构特性中硬度显著(p<0.05)减小,弹性、黏聚性、咀嚼性先增大后减小,在添加量为50%时最大;蒸煮损失率显著(p<0.05)增大。结合感官品质、质构特性、蒸煮损失率结果,马铃薯全粉添加量≤50%时,加工出的马铃薯挤压重组米品质较好。马铃薯全粉的添加量、马铃薯全粉-碎米混合粉糊化特性与马铃薯挤压重组米品质特性存在显著(p<0.05)相关性。     

Breadmaking performance of protein enriched,gluten-free breads

Soybean enriched, rice-based gluten-free breads were designed incorporating a structuring agent (hydroxypropylmethylcellulose, HPMC) and a processing aid (transglutaminase, TG). At dough level the effect of increasing amounts of soybean protein isolate (SPI), HPMC and water was studied in the Mixolab. Mixing and thermal characteristics showed the significant effect induced by water, soybean protein isolate, HPMC and TG, allowing the selection of the appropriate amounts for the breadmaking performance of enriched gluten-free breads. The single addition or in combination of 4% HPMC, 13% soybean and 1% TG produced significant changes in the physical properties of the rice-based gluten-free breads. The presence of SPI blended with rice flour produced a significant decrease in the specific volume of the bread, although this detrimental effect was partially counteracted by its combination with HPMC, decreasing also the crumb hardness. The micrographs of the crumb showed the beneficial effect of the HPMC, obtaining a more open aerated structure. Protein enriched, gluten-free breads can be obtained with a combination of SPI, HPMC and TG.     

Effect of hydroxypropyl methylcellulose,whey protein concentrate and soy protein isolate enrichment on characteristics of gluten‐free rice dough and bread

Due to a lack of gluten, rice dough needed some additives to improve its properties. This study aimed to investigate effect of hydroxypropyl methylcellulose (HPMC), whey protein concentrate (WPC) and soy protein isolate (SPI) on rice dough and bread. HPMC increased water absorption of the rice dough (P ≤ 0.05). Adding SPI (2–4 g per 100 g flour) together with HPMC tended to increase stability time and reduce tolerance index. During fermentation, HPMC increased maximum dough height, while SPI increased final dough height (P ≤ 0.05). All addition improved tan δ (G″/G′) to be comparable to the wheat dough, but it could not improve gas production and retention. Therefore, specific volume, springiness, cohesiveness and chewiness of rice bread were lower than those of wheat bread (P ≤ 0.05). Percentage of small pores in rice bread was reduced to be comparable to wheat bread, by adding WPC. All addition could improve porosity of the rice bread.     

Production of high-fructose rice syrup and high-protein rice flour from broken rice

The objective of this study was to develop a process for the production of both high-fructose rice syrup and high-protein rice flour from broken rice. The rice flour was obtained from broken rice by using either a dry or wet milling method. The glucose produced from the slurry of various raw materials by treating with α-amylase and glucoamylase was compared. Results indicated that cassava and corn starch were better raw materials than rice flour. However, the filtered residue of liquefied rice slurry could be recovered as high-protein rice flour. The particle size of rice flour had a small effect on the glucose yield. The orthogonal-array table (L₂₇) method of experimental design was employed to determine optimum conditions for liquefaction. The glucose yield based on starch was 90.8±3.6% under the following optimum conditions α-amylase, 0.12%; rice flour, 20%; temperature, 96°C; time, 90 min. The filtrate from liquefied rice slurry was saccharified at 60°C with three different concentrations of glucoamylase. The higher the enzyme concentration, the shorter the time required to reach the maximum yield. After saccharification, the glucose solution was decolourised, desalted and concentrated to 40% d.s. and then isomerised to fructose at 60°C under continuous operation by using immobilised glucose isomerase packed in a column. The isomerised syrup was then purified and concentrated to 71% d.s. The final high-fructose rice syrup contained 50% glucose, 42% fructose and 3% maltose. After liquefaction, the rice slurry was centrifuged and the precipitate was dried by either spray or drum drying. The composition of these two high-protein rice flours was almost the same and the protein content was about three times as high as the raw material. There were significant differences in surface structure of rice flour and high-protein rice flours, as observed by the scanning electron microscope.     

Soybean protein isolate-rice starch interactions during the simulated gluten-free rice bread making process

Gluten-free bread (GFB) is usually of poor quality due to lack of gluten. Addition of exogenous protein is one of the important ways to improve the quality of GFB products. In this study, different levels of soybean protein isolate (SPI) mixed with rice starch (RS) system were prepared to simulate different processing stages during bread making. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), rapid viscosity analysis (RVA), confocal laser scanning microscopy (CLSM), texture analyser and rheometer were used to analyse the effects of SPI on the structural, microstructure and functional properties of RS. The results showed that: hydrogen bonds could be formed between SPI and RS, thus improving the stability of RS; compared with RS, the ∆H and setback values of the blend were reduced by 43.79% and 34.53%, respectively, when SPI was added at 12%; and the storage modulus (G') and loss modulus (G") reached the minimum value at 9% SPI content. CLSM and texture analysis show that the addition of protein inhibits the leaching of starch, reduces the hardness, chewiness and gumminess of the system, which is conducive to the quality of GFB.     

Characteristics of Bread Prepared from Wheat Flours Blended with Various Kinds of Newly Developed Rice Flours

ABSTRACT:  Characteristics of the bread prepared from wheat flour blended with the flour of various kinds of newly developed rice cultivars were investigated. Qualities of the bread made from wheat flour blended with rice flour have been reported to be inferior to those from 100% wheat flour bread. To improve its qualities, we searched for the new-characteristic rice flours among the various kinds of newly developed rice cultivars to blend with the wheat flour for the bread preparation. The most suitable new characteristic rices are combination of purple waxy rice, high-amylose rice, and sugary rice. Specific volume of the bread from the combination of wheat and these 3 kinds of rice flours showed higher specific volume (3.93) compared with the traditional wheat/rice bread (3.58). We adopted the novel method, continuous progressive compression test, to measure the physical properties of the dough and the bread in addition to the sensory evaluation. As a result of the selection of the most suitable rice cultivars and blending ratio with the wheat flour, we could develop the novel wheat/rice bread, of which loaf volume, physical properties, and tastes are acceptable and resistant to firming on even 4 d after the bread preparation.
To increase the ratio of rice to wheat, we tried to add a part of rice as cooked rice grains. The specific volume and qualities of the bread were maintained well although the rice content of total flour increased from 30% to 40%.     

Effects of rice properties and emulsifiers on the quality of rice pasta

Two commercial rice flours (GTIndica and GTJaponica, with amylose contents of 306.8 and 185.2 g kg^?1 respectively) and their blended flours were used to make rice pasta. The effects of two emulsifiers (distilled glyceryl monostearate (GMS) and a commercial emulsifier (KM3000)) on the pasting and thermal properties of dried rice pasta were investigated using a Rapid Visco Analyser (RVA) and a differential scanning calorimeter (DSC). The rice pasta made from high‐amylose rice flour had better extrusion properties, better texture, whiter colour, less cooking loss and better eating quality than that made from low‐amylose rice flour. The maximum amount of low‐amylose rice flour that could be blended in for making an acceptable quality of rice pasta was 500 g kg^?1. A soft texture, low adhesiveness and low gumminess of cooked rice pasta were obtained by adding 10 g kg^?1 GMS. SEM investigations showed that use of an emulsifier restricted the swelling of starch granules, especially for the pasta made from high‐amylose rice flour. © 2001 Society of Chemical Industry     

Influence of phosphorylated rice flour on the quality of gluten‐free bread

The chemical modification of rice flour by phosphorylation is an alternative to improve the technological quality of bakery products. The aim of this study was to investigate the effect of phosphorylation process of rice flour on technological properties (specific volume, crumb and crust colour) of gluten‐free breads and the hardening of these breads during two storage temperatures (21 °C and ?24 °C). Breads were made with native rice flour, with phosphorylated rice flour and with wheat flour, used as control. The phosphorylation causes significant reduction in the synaeresis of pastes and in retrogradation tendency of rice flours, varying from 258.7 cP (native rice flour) to 122 cP (phosphorylated rice flour). The breads prepared with phosphorylated rice flour showed reduction in the hardness in both storage temperatures studied and effect on rice bread volume, crumb appearance and colour, demonstrating the possibility of use of the phosphorylated rice flour in gluten‐free breads.     

Rice varieties in relation to rice bread quality

BACKGROUND: It is difficult to predict rice bread quality only from the amylose content (AC) or dough characteristics of new lines produced by rice breeding programmes. This study investigated the AC relative to bread baking quality of rice varieties developed in Korea, and identified specific characteristics that contribute to rice bread quality. RESULTS: Manmibyeo, Jinsumi, Seolgaeng and Hanareumbyeo were classified as low AC, YR24088 Acp9, Suweon517, Chenmaai and Goamibyeo as intermediate AC and Milyang261 as high AC. Suweon517, Milyang261 and Manmibyeo had a high water absorption index (WAI), while Goamibyeo, YR24088 Acp9, Jinsumi, Seolgaeng, Hanareumbyeo and Chenmaai had a low WAI. The gelatinisation enthalpy of flour varied from 9.2 J g^?1 in Milyang261 to 14.8 J g^?1 in YR24088 Acp9 . After 7 days of storage the rate of flour retrogradation and crumb firmness were weakly correlated, with the exception of Jinsumi . Bread volumes of Jinsumi, Chenmaai, YR24088 Acp9 and Goamibyeo were comparable to that of wheat flour, but the rest were unsuited to bread making because of their low volume and hard crumb texture. CONCLUSION: Based on volume, texture and crumb firmness ratio, Chenmaai and Goamibyeo were the most appropriate varieties for making bread. An intermediate AC and low WAI were the primary indicators of rice bread flour quality. Copyright © 2011 Society of Chemical Industry     

The effects of extruded black rice flour on rheological and structural properties of wheat-based dough and bread quality

Addition of raw black rice flour leads to deficient processability on bread making quality. One of the effective methods to modify the functional properties of black rice flour (BRF) composite dough is to extrude black rice flour (EBRF) before incorporation. This study investigated and compared the effect of BRF and EBRF addition level of 10%–50% on the rheology, microstructure of dough and bread quality. The rheological properties of composite dough were recorded by Mixolab, stress relaxation and tensile test. The substitution of EBRF presented higher water absorption but lower development time, protein weakening, starch gelatinization, starch gel stability and starch retrogradation than wheat flour dough. Both the BRF and EBRF dough presented solid-like behaviour, while the EBRF dough showed more viscous, higher resistance and extensibility than BRF dough. The dough microstructure of dough was observed by SEM, and a more compact structure of EBRF dough could be seen than BRF dough. The incorporation of EBRF in bread quality presented higher specific volume, lower bake loss and firmness than BRF bread. These findings indicated the potential utilisation value of extruded black rice flour in bread making.     

板栗黄酒渣粉对小麦粉面包品质特性、微观结构、生物活性成分及抗氧化性影响的研究

为了提高板栗资源的利用率,将板栗黄酒渣粉(Chinese chestnut rice wine residue flour,WRF)作为膳食纤维源和生物活性物质源应用于小麦粉面包中,以改善小麦粉面包的营养结构并探讨开发WRF强化面包的可行性。研究了自然干燥板栗黄酒渣粉(Natural-dried Chinese chestnut rice wine residue flour,NDWRF),烘箱干燥板栗黄酒渣粉(Oven-dried Chinese chestnut rice wine residue flour,ODWRF),真空冷冻干燥板栗黄酒渣粉(Vacuum freeze-dried Chinese chestnut rice wine residue flour,VFDWRF)的基本组成成分、理化特性、微观结构以及以WRF作为膳食纤维源和生物活性物质源添加到小麦粉面包中,对其品质特性、微观结构、生物活性成分及抗氧化性的影响。试验表明,3种干燥方式渣粉的基本营养成分、膳食纤维、总多酚、总黄酮和类胡萝卜素含量以及pH、色度L*、a*、b*值、持水力、持油力、溶胀力、DPPH自由基清除率、ABTS自由基清除率、铁还原能力均存在显著性差异,其扫描电镜微观结构差异不显著,傅里叶红外光谱分析其结构基团基本相同,X射线衍射图谱分析其晶体结构存在明显差异。WRF的不同添加水平对小麦粉面包的理化特性、质构特性、微观结构、生物活性物质含量、抗氧化特性以及感官特性均具有显著性影响。2%~4%WRF添加水平对小麦粉面包总体可接受性影响不显著,3种WRF可纳入小麦粉面包的最高水平均达4%。