Oil Binding Ability of Chlorinated and Heated Wheat Starch Granules and Their Use in Breadmaking and Pancake Baking

Chlorination and heat treatment of wheat flour changes the surface character of starch granules from hydrophilic to hydrophobic, and high oil binding ability of the starch granules can be observed. It was suggested that the hydrophobicity, in case of chlorination, was due to chemical modification of the starch granule surface proteins, and, in case of heat treatment, due to conformational changes of the proteins. This hydrophobicity could be also obtained by aging (233 days at room temperature). The hydrophobicity of starch granules in batter is highly related to the springiness of pancake. Heat treated wheat starch granules can encapsulate flavor through their oil binding ability.     

脱脂大豆粉对小麦粉及馒头品质影响研究

将脱脂大豆粉添加到小麦粉中,研究其对小麦粉理化特性和馒头制作品质的影响。研究结果表明,在小麦粉中添加低于2%的脱脂大豆粉时,可以明显地改善小麦粉的品质,具体体现在可以增加面粉的白度,增加面团的吸水量、稳定时间以及拉伸曲线面积和拉伸比数,还可以改善馒头的品质;当在小麦粉中添加高于2%的脱脂大豆粉时,其对面粉的品质具有不好的影响,具体体现在降低小麦粉的白度以及面团的筋力,对馒头的品质也具有不良的影响,表现为馒头体积变小,颜色发暗。     

法国小麦品质及其与中国小麦搭配制粉研究

研究了法国小麦(FW-P11)及4种中国小麦品种的理化品质;并在此基础上,设计法麦与以上中国小麦的搭配比例,研究其混合粉的品质及食品加工性能,进行了馒头、面条、面包制作试验。结果表明:法麦(FW-P11)灰分含量低、出粉率高、蛋白质损失率低、面筋含量低但面筋指数高,是一种优质的低筋小麦;与中国小麦搭配后,混合粉的湿面筋含量有所提高;法麦(FW-P11)与江苏低筋红麦按1∶1搭配时,表现出良好的蒸煮特性,可以制作出优质的馒头;法麦(FW-P11)与江苏中筋红麦按1∶1搭配时,表现出良好的面条加工性能;法麦(FW-P11)与河南豫麦34按1∶1搭配时,表现出良好的烘焙特性,能制作出品质优良的面包。研究显示,法国小麦与中国主要小麦品种合理搭配使用,可以优势互补,达到生产不同专用粉的目的。     

小麦籽实糊粉层与面粉品质的关系

本文从小麦籽实糊粉层细胞组织具有丰富的营养成分方面进行了分析；对改良和强化优质面粉烘焙品质及保持天然营养成分进行了科学的论证。     

Physicochemical and Functional Properties of Tetraploid and Hexaploid Waxy Wheat Starch

Waxy wheats possess unique starch functional properties that may be useful in specific end‐uses. To assess the physicochemical, thermal, and pasting properties, starches from seven waxy genotypes originating from two wheat classes, tetraploid durum and hexaploid hard red spring (HRS), were evaluated and compared with their counterpart non‐waxy wild types. The amylose content ranged from 2.3% to 2.6% in waxy durum lines, compared to 29.2% in normal durum control, and 2.1% to 2.4% in waxy HRS, compared with 26.0% in normal HRS control. Significant differences in the degree of crystallinity were observed between the waxy and control starches, despite similar A‐type X‐ray patterns, although differences between the two wheat classes were non‐significant. Both, control and waxy starches displayed an X‐ray peak corresponding to the amylose‐lipid complex, but the intensity of the peak was markedly lower in the waxy starches. The waxy durum starches exhibited the highest transition temperatures as measured by Differential Scanning Calorimetry (DSC), whereas, the enthalpy of gelatinization of most waxy genotypes was statistically higher than that of the controls. All waxy starches displayed high peak viscosity, high breakdown, and low setback profile as measured by the Rapid Visco Analyser (RVA). Texture analysis of RVA gels revealed significant differences between waxy and non‐waxy wheats, as well as between waxy tetraploid and hexaploid wheats, confirming that the nature and class of wheat starch would play a significant role when using waxy wheat blends in different wheat‐based products.     

小麦粉粒度变化与淀粉损伤程度

从小麦淀粉的原生态(粒径大小与分布)出发,首先拿等级粉的粗细度与之比较,分辨淀粉损伤的综合程度和倾向,进而对工艺中各研磨部位的面粉粒度、淀粉损伤程度进行分析研讨,以化验的量化结果,揭示淀粉损伤的真实面貌。紧紧抓住面粉粒度变化和淀粉损伤程度的同步因素,逐渐深入,诠释不被重视的等级粉淀粉损伤原因和专用粉能适应不同面制品要求的理论基础,提出了研究淀粉损伤和面粉粒度是制粉工艺研究的当务之急。     

Development of a Method for Evaluating Floor Dry‐Cleanability from Wheat Flour in the Food Industry

Many productive processes are characterized by inadequate protocols of sanitation that increase the possibility of proliferation of microbial contaminants, especially on surfaces. The use of this method for evaluating the degree of floor cleanability in agri‐food companies is important not only to reduce the risk of contamination of products, but also to provide companies with a tool to identify critical issues. The method is based on the usage of bicinchoninic acid assay (BCA) in a solution at a 1:50 ratio of Cu²⁺/BCA, which is ideal for detecting the amount of proteins contained in wheat flour residues on industrial flooring. Spectrophotometric analysis allowed identifying maximum absorbance values at 562 nm for different protein concentrations, although the construction of a regression function led to the definition of the intervals of evaluation corresponding to different degrees of cleanliness from residues of wheat flour. The results of the absorbance curves, obtained by applying the proposed evaluation method to 6 tiles commonly used in agri‐food buildings, showed the clear persistence of food material on 2 tiles with surface relief. In particular, such tiles showed a higher presence of proteins, with a level of contamination 440% higher. Furthermore, a robotic system was designed to standardize the cleaning method commonly employed in agri‐food companies to remove solid particles from flooring.     

不同溶剂分离重组游离脂对面粉品质的影响

本文采用氯仿、石油醚和正己烷三种溶剂,分别使用快速抽提和索氏抽提两种方法分离面粉中的游离脂,比较原面粉和游离脂重组面粉的品质差异。结果表明:在三种溶剂中,氯仿的提油率最高(0.94%,1.18%),正己烷其次,石油醚最低(0.71%,0.77%)。与原面粉相比,氯仿索氏抽提分离重组面粉的面筋指数和粉质特性变化最大(形成时间和稳定时间分别由5.65 min和9 min增大到13 min和18.8 min);使用石油醚索氏抽提法分离重组面粉中的游离脂,对面粉的面筋指数、形成时间、稳定时间和粘度特性(回生值除外)影响不显著。与原面粉制作的面条相比,石油醚索氏抽提重组粉制作面条的黏聚性和弹性无显著变化。因此,采用石油醚索氏抽提分离重组面粉中的游离脂,是一种理想的不破坏面粉性质的游离脂分离方法。     

小麦粉受热对面团流变学特性及馒头品质的影响

小麦粉在加工过程中受到热的影响,其品质及面制品品质发生变化。该研究主要研究小麦粉受热后面团流变学特性及馒头品质变化。采用干热处理方式,在60~90 ℃条件下分别对小麦粉处理10~50 s,测定面团糊化、粉质和拉伸特性及馒头色泽、质构等。结果表明：与原粉相比,受热后小麦粉的峰值黏度降低7.01%、最低黏度降低9.44%、最终黏度降低5.58%、衰减值增加10.25%、回生值增加8.38%、面团拉伸曲线面积降低19.74%、延展性降低12.77%,随着时间的延长,拉伸阻力呈先升高后降低趋势。处理温度和时间对小麦粉的形成时间无显著性影响,随着处理温度的升高,稳定时间降低10.74%、弱化度增加9.90%。受热后馒头的宽高比和比容分别增加17.81%和22.22%、色泽变差、硬度降低62.25%、粘性降低75.64%、咀嚼性降低63.46%。综上所述小麦粉适度受热可以改善馒头的品质。     

添加膳食纤维对面团及面制品品质的影响

越来越多的证据表明,膳食纤维的摄入量与慢性疾病之间有很密切的联系.但是膳食纤维的摄入量通常低于推荐量,因此,研究和开发高膳食纤维食品是很有必要的.本文综述了近几年国内外对高纤维面制品的研究进展,并对不同膳食纤维对面团流变学性质的影响作了总结,以期推动这方面产业的发展.     

小麦粉及其制品中偶氮甲酰胺检测方法研究进展

偶氮甲酰胺(azodicarbonamide,ADA)是小麦粉常用的食品添加剂,具有增白、强筋作用.ADA在湿热环境下不稳定,能够转化为联二脲(biurea,BIU)和氨基脲(semicarbazide,SEM).SEM是兽药呋喃西林的代谢物,具有较强的致癌、致畸、致突变作用.小麦粉及其制品中ADA检测方法可分为直接检...     

制粉工艺对小麦粉粉质特性和糊化特性的影响

使用快速粘度分析仪(RVA)测定了采用脱皮制粉工艺和传统制粉工艺生产得到的小麦粉的糊化特性,并通过测定小麦粉的损伤淀粉含量等,考察了两种工艺条件下,小麦粉糊化特性和粉质特性间的关系。结果显示,脱皮工艺小麦粉的损伤淀粉含量减少,淀粉平均粒度大,而α-淀粉酶含量减少。制粉工艺对中筋的南阳白麦和高筋的8901特二粉的影响最为明显,脱皮工艺小麦粉的峰值粘度和最终粘度明显增加,而其他样品基本不变;同时,这两种样品的衰减度较大,而其他样品的衰减度则有所减小。脱皮制粉得到的所有样品的低谷粘度均高于采用传统工艺的同等小麦粉,但回生值较低。     

Microbial Diversity of Type I Sourdoughs Prepared and Back‐Slopped with Wholemeal and Refined Soft (Triticum aestivum) Wheat Flours

The fermentation of type I sourdough was studied for 20 d with daily back‐slopping under laboratory and artisan bakery conditions using 1 wholemeal and 2 refined soft wheat (Triticum aestivum) flours. The sourdough bacterial and yeast diversity and dynamics were investigated by plate counting and a combination of culture‐dependent and culture‐independent PCR‐DGGE approach. The pH, total titrable acidity, and concentration of key organic acids (phytic, lactic, and acetic) were measured. Three flours differed for both chemical and rheological properties. A microbial succession was observed, with the atypical sourdough species detected at day 0 (i.e. Lactococcus lactis and Leuconostoc holzapfelii/citreum group for bacteria and Candida silvae and Wickerhamomyces anomalus for yeasts) being progressively replaced by taxa more adapted to the sourdough ecosystem (Lactobacillus brevis, Lactobacillus alimentarius/paralimentarius, Saccharomyces cerevisiae). In mature sourdoughs, a notably different species composition was observed. As sourdoughs propagated with the same flour at laboratory and artisan bakery level were compared, the influence of both the substrate and the propagation environment on microbial diversity was assumed.     

吹泡仪在控制饼干专用粉的小麦及面粉品质特性中的应用

本文主要讨论如何用吹泡仪来控制饼干专用粉的小麦原料的品质特性,制粉生产过程中的面粉品质特性及面粉和小麦的储存时间对其品质的影响,从而通过吹泡仪的检测数据的分析,提高对产品质量的监控能力,保证产品质量的稳定,进一步满足顾客的使用要求。     

Characteristics and oil absorption of deep‐fat fried dough prepared from ball‐milled wheat flour

BACKGROUND: High levels of oil in fried products has been recognized as causing health problems. The formation of microstructure during frying is one factor that influences oil absorption. Above the glass transition temperature (T_g), the physical properties of a polymer influences the formation of structure. The ball‐milling process changes the physicochemical properties of wheat flour constituents. The present study investigated the effects of physicochemical changes in wheat flour by the ball‐milling process on structure formation and oil absorption in wheat flour dough model. RESULTS: Dough samples were made from wheat flour that had been ball‐milled for 0 to 10 h and then fried in frying oil at 150 °C for 1–7 min. Thermal properties of wheat flour, structure alteration, and textural properties of fried samples were evaluated. As compared with samples made of non‐milled flour, samples made from milled flour had smaller pores and higher oil absorption. The fracture force of a fried sample prepared from non‐milled flour was lower than that of a sample prepared from milled flour. CONCLUSION: Ball‐milling affected the microstructure formation in fried wheat flour dough, and subsequently oil absorption. The crispness of a sample prepared from non‐milled wheat flour is higher than that of a sample prepared from ball‐milled wheat flour. This may be due not only to a plasticization effect, but may also be dependent on microstructure. Copyright © 2008 Society of Chemical Industry