高压射流磨处理对燕麦浆稳定性的影响

目的：研究高压射流磨对燕麦浆稳定性的影响及机制,为全谷物饮料加工提供依据。方法：采用不同压力高压射流磨对燕麦浆进行处理,比较贮藏期（30 d）的形态、不稳定指数、粒径、流变特性变化,并对微观形貌（光学显微镜、激光共聚焦扫描显微镜、扫描电子显微镜）、可溶性成分含量（可溶性固形物、可溶性蛋白、可溶性膳食纤维）进行分析。结果：高压射流磨处理使燕麦浆的粒径、不稳定指数、表观黏度逐渐减小,并能减缓淀粉的老化和颗粒的聚集。高压射流磨能均化蛋白和油脂,破坏细胞壁组织纤维,使更多可溶性物质溶出,并在颗粒内部产生孔腔,增加水合能力,提高体系总体稳定性。结论：高压射流磨技术可提高全谷物产品贮藏稳定性,延长货架期。     

燕麦发芽过程中营养物质的变化研究

本文以燕麦为原料,以β-葡聚糖、总多酚、蛋白质体外消化率(IVPD)、不溶及可溶膳食纤维含量为评价指标,探讨燕麦在发芽过程中淀粉、β-葡聚糖、总多酚及膳食纤维等营养物质的变化规律。结果表明从浸麦到发芽5d过程的不同状态中,随着时间的延长,燕麦蛋白质体外消化率、总多酚含量、可溶性膳食纤维都大幅度增加,而β-葡聚糖的含量和不溶性膳食纤维含量明显降低。当发芽时间达到5d时,总多酚含量增加30.46%,IVPD值增加138.6%,可溶性膳食纤维增加59.74%,而β-葡聚糖含量下降近80.38%,不溶性膳食纤维减少19.56%。说明燕麦从浸麦到发芽过程中,在一定程度上提高了燕麦的营养价值,但同时降低了β-葡聚糖和不溶性膳食纤维等相关功能特性,为燕麦的后续加工提供一定的基础。     

不同热处理对燕麦全谷营养品质及消化性的影响

为了解热处理方法对燕麦全谷营养品质及消化性的影响,采用常压蒸制、高压蒸制、微波和炒制4种方法处理燕麦全谷,分析了热处理对燕麦全谷中基本营养成分、膳食纤维组分及淀粉和蛋白质体外消化的影响。结果表明,常压蒸制使燕麦全谷中蛋白质、总膳食纤维(TDF)、β-葡聚糖含量显著下降;高压蒸制使TDF增加而β-葡聚糖含量下降(p0.05);微波处理后全谷TDF和β-葡聚糖下降,脂肪含量提高(p0.05);炒制则使脂肪、TDF和β-葡聚糖含量分别提高22.9%,6.1%和15.61%(p0.05)。不同热处理后燕麦全谷快消化淀粉含量均显著增加;而除炒制外抗性淀粉(RS)含量均下降,炒制后RS提高7.4%(p0.05)。燕麦全谷的蛋白质消化率经微波和常压蒸制后显著增加;高压蒸制后降低(p0.05);而炒制后无显著变化(p0.05)。说明炒制更适合燕麦功能保健食品的加工。     

高压微射流对葡聚糖理化性质和结构的影响

为了研究高压微射流对葡聚糖理化性质和结构的影响,采用高压微射流在40、80、120、160 MPa下对葡聚糖进行处理,研究对溶液中还原糖和葡聚糖链长的变化情况,以及对粒径、黏度和热稳定的影响。结果表明,随着压力的增加,还原糖呈现先增加后减少的趋势,葡聚糖链的断开情况为先增加后减少,粒径尺寸和黏度减小。傅里叶红外光谱图显示葡聚糖的二级结构发生了变化,扫描电镜图显示样品颗粒变小。表明高压微射流影响了葡聚糖的结构,从而影响了理化性质,可以为其在食品工业中的应用提供了理论依据。     

加工方式对燕麦制品营养成分及功能特性的影响

以白燕2号燕麦籽粒为对照样品,研究不同加工方式制得的燕麦米、燕麦片、燕麦糊、燕麦粉和燕麦窝窝的营养品质差异。比较不同燕麦制品主要营养成分含量差异,及蛋白质和β-葡聚糖的分子量等分子结构变化。结果表明：五种燕麦制品中燕麦米和燕麦片的热量值、脂肪含量较低,且灰分、矿物质、氨基酸、淀粉、β-葡聚糖损失较少,营养品质高于其他制品,燕麦糊营养成分损失最大。热加工（三熟工艺、高温挤压）会破坏蛋白质结构,诱导其展开重新聚集,分子量增大;导致β-葡聚糖裂解,分子量减小,黏度降低。燕麦糊高温挤压膨化过程导致功能成分β-葡聚糖分子量显著降低,因此适当调整挤压等高温加工参数可以有效保留燕麦的功能特性。     

燕麦β-葡聚糖、多酚及黄酮的抑菌活性研究

为探究燕麦中β-葡聚糖、多酚及黄酮的抑菌活性,以燕麦为原材料,提取其中的β-葡聚糖、多酚及黄酮,以大肠埃希氏菌、枯草芽孢杆菌、产酯酵母以及黑曲霉4种菌为供试菌种,采用滤纸片法和牛津杯法研究各物质对4种供试菌的抑菌效果。试验结果表明：两种测定方法显示燕麦β-葡聚糖、多酚以及黄酮对以上4种供试菌均有一定的抑制作用,其中燕麦多酚的抑菌活性最强,黄酮次之,β-葡聚糖最弱,且其抑菌能力均与活性物质浓度呈正相关,3种物质对4种供试菌的抑菌作用大小均表现为：大肠埃希氏菌＞枯草芽孢杆菌＞产酯酵母＞黑曲霉。该研究表明燕麦β-葡聚糖、多酚及黄酮具有一定抑菌活性,这为燕麦活性成分在食品防腐方面的开发利用提供一定数据支撑。     

动态高压微射流对马铃薯直链淀粉性质和结构的影响

采用动态高压微射流(DHPM)对马铃薯直链淀粉进行处理,研究了不同处理压力(80、120、160、200MPa)对直链淀粉理化性质及结构的影响。结果表明:经DHPM处理后,马铃薯直链淀粉溶解度、膨润力、透明度随压力增加先增大后减小,在160 MPa处理时达到最大,而其冻融稳定性的变化无显著规律;马铃薯直链淀粉凝胶硬度、弹性、内聚性、胶着性和咀嚼性随压力增加均呈现先增加后降低的变化趋势,且均在120 MPa达到最大值,而凝胶黏性随着处理压力的增大逐渐减小;粒度分析表明,直链淀粉的平均粒径随着处理压力的增大呈现先减小后增大趋势,经80 MPa处理后平均粒径最小;原子力显微镜(AFM)观察显示经过200 MPa处理的马铃薯淀粉的微观结构发生改变,3D高度减小,平均分子质量减小,分子质量分布更加均匀。     

萌发及甜醅发酵处理对燕麦营养品质、淀粉体外消化能力及抗氧化性的影响

以河北张家口产裸燕麦为对照,以萌发、甜醅发酵、萌发后再发酵三种处理为实验组,测定燕麦中总多酚含量、黄酮含量、β-葡聚糖含量、游离氨基酸含量、DPPH自由基清除率、羟基自由基清除率及淀粉体外消化能力,探究萌发、甜醅发酵、萌发后发酵等三种不同处理对燕麦淀粉体外消化及抗氧化能力的影响。结果显示：萌发、甜醅发酵、萌发后发酵等三种不同处理对燕麦的营养性、抗氧化性均有一定程度的影响,其中先萌发再发酵处理影响显著（p<0.05）,影响效果高于单独萌发与发酵;处理后燕麦淀粉的体外消化率的变化趋势则比对照平缓,RDS含量有一定程度提高,但SDS和RS的含量无显著变化（p>0.05）。     

β-葡聚糖对燕麦淀粉凝胶特性及老化的影响

燕麦淀粉与β-葡聚糖的相互作用在燕麦面团的形成中发挥着重要的作用。为研究β-葡聚糖对燕麦淀粉的影响,将不同比例β-葡聚糖添加到燕麦淀粉中,测定复配体系的微观结构、流变学特性等,并探究β-葡聚糖对淀粉老化的影响。结果表明:随着β-葡聚糖添加量的提高,复配体系颗粒粒径显著减小,形成致密、连续的类蜂窝状网络结构,糊化焓值升高,表明复配体系具有较好的稳定性。红外分析表明复配体系并未形成新的基团,主要通过氢键作用形成网络结构。β-葡聚糖的添加可以显著降低复配体系凝胶的硬度,增加弹性,改善淀粉食品品质。β-葡聚糖提高了复配体系糊化温度和峰值时间,降低了崩解值和回生值,表现出更好的热稳定性和抗老化性。添加β-葡聚糖后,复配体系仍表现出弱凝胶动态流变学特性。与燕麦淀粉相比,β-葡聚糖添加量为5%～10%的复配体系黏弹性增强,稠度系数增大,剪切变稀现象更明显,其中添加量为10%的复配体系固体性质表现最明显;添加量为15%～20%的复配体系黏弹性降低,剪切稳定性提高;添加10%β-葡聚糖可以抑制燕麦淀粉的长期回生。本研究结果可为复配体系在食品加工中的应用提供参考。     

高压微射流处理对白木通籽分离蛋白结构及流变性质的影响

本文采用了傅里叶红外光谱(FT-IR)和稳态剪切流变学等分析方法研究了高压微射流处理(0.1、50、90、130、170 MPa)对白木通籽分离蛋白结构及流变性质的影响。结果表明:经过高压微射流处理,白木通籽分离蛋白的粒径变小;SDS-PAGE电泳结果表明,蛋白亚基未受影响;溶解性得到显著提高;总巯基以及暴露巯基的含量随着处理压力的增大呈下降趋势;FTIR结果表明,分离蛋白的二级结构组成发生了变化,在130 MPa时变化最大,并且蛋白的不稳定结构如β-sheet、Random coil含量减少,稳定的蛋白结构β-turn含量增加,样品构象稳定性提高。白木通籽分离蛋白溶液经微射流处理前后均是假塑性流体,在剪切速率为0~10 s-1范围内,表观粘度呈递减的趋势;同时随着样品处理压力的增大,表观粘度发生明显的剪切稀化现象。     

Influence of damaged starch on cookie and bread-making quality

In this study two wheat and one triticale cultivars were milled in a disc mill to obtain different levels of damaged starch. The effects of the damaged starch content on physicochemical flour tests and cookie and bread-making quality were analyzed. The grain milling conditions in disc mill and grain hardness influenced the amount of damaged starch. The solvent absorption of flours, as measured by Solvent Retention Capacity Profile (SRC) and Alkaline Water Retention Capacity (AWRC), was significantly incremented by the damaged starch content. There was a consistent loss in cookie quality as the damaged starch content increased. In spite of the fact that the proteins were not affected by flour milling, bread quality decreased as the damaged starch content increased.     

山药淀粉与燕麦β-葡聚糖共混体系理化及消化性能研究

为研究燕麦β-葡聚糖对山药淀粉的影响,采用快速粘度分析仪制备山药淀粉与燕麦β-葡聚糖共混体系,测定了共混体系的糊化性质、热特性、流变性和消化性能等。糊化特性分析表明,燕麦β-葡聚糖能够降低山药淀粉的黏度、回生值,抑制山药淀粉的短期回生。热特性结果表明,燕麦β-葡聚糖的加入使共混体系的糊化焓ΔH显著降低（P<0.05）,最低值为7.34 J/g。红外谱图分析表明,山药淀粉与燕麦β-葡聚糖之间未发生共价结合,主要通过氢键作用。质构特性分析表明,燕麦β-葡聚糖的添加使共混体系凝胶结构变弱。静态流变学特性分析表明,燕麦β-葡聚糖的加入使共混体系的表观黏度降低;动态流变学特性分析表明,燕麦β-葡聚糖可显著降低山药淀粉的黏弹性。X射线衍射结果表明,凝胶作用改变了晶体类型,且相对结晶度从38.40%降至16.30%。此外,燕麦β-葡聚糖的加入,降低了共混体系的消化性,提高了抗性淀粉含量,最高值为49.24%。本研究可为开发燕麦β-葡聚糖/淀粉基食品提供理论依据。     

脱脂对燕麦淀粉理化性质影响研究

研究了燕麦粉的脱脂条件和脱脂对燕麦淀粉性质的影响.结果表明:燕麦粉脱脂条件为料液比为1∶4,脱脂时间4h;燕麦淀粉经脱脂后粗脂肪和损伤淀粉含量分别降低81.3％、26.9％;燕麦破损淀粉含量由4.64％下降至3.63％;燕麦淀粉经脱脂透光率增加、沉降体积变小、冻融吸水率下降;经脱脂后燕麦淀粉溶解度下降,膨润力变高;经脱脂燕麦淀粉峰值黏度升高,谷值黏度基本不变,衰减值、最终黏度、回生值、糊化温度均有所下降.     

Effects of high energy milling on some functional properties of jicama starch (Pachyrrhizus erosus L. Urban) and cassava starch (Manihot esculenta Crantz)

In this study, the effect of high energy milling using a Spex ball mixer mill on some functional properties of cassava starch (Manihot utilissima) and jicama starch (Pachyrrisus erosus) were investigated. The properties of individual granules were strongly influenced by the high moisture of ball milling (friction and heat) and physicochemical properties of their amorphous and crystalline zones. High energy milling resulted in a partial fragmentation of the starch granules, increasing the water absorption index (WAI) and the water solubility index (WSI). Increasing moisture content the viscosity was decreased, attributable to the fragmentation of starch granules produced by the milling and favored by the increase of moisture content.The crystallinity of cassava and jicama starches milled with high moisture contents and longer milling times was decreased. Thermal properties of both ball-milled starches were modified. The enthalpies were lower than native starch indicating that ball milling destroys the crystallinity and double helical order arrangements. Also, the resolution of the peaks was slightly decreased. Ball-milled jicama and cassava starches showed some functional characteristics of gelatinization that possibility their use in food systems as stabilizing, additives, moisture retainers and thickeners.     

Technological performance of various flours obtained through multigrain milling

This study was focused on multigrain flours consisting on wheat-rye-triticale and wheat-rye-hulled oat, obtained by using an experimental Buhler roller mill after blending the cereals at different levels. For all investigated multigrain blends the extraction yield of the first reduction passage was lower compared to wheat. The flour yields at the break roll passages decreased in the flowing order: blends with triticale, wheat and blends with hulled oat. The multigrain milling resulted in increased ash, crude fiber and fat contents, and decreased protein content compared to wheat. The solvent retention capacity profile varied with the type of blend, and important correlations were established with Mixolab parameters, mainly related to starch gelatinisation and breakdown. Texture measurements performed on breads prepared with multigrain flours indicated increased hardness and decreased springiness values with increasing the wheat substitution level. These results might allow better exploitation of different cereals through the efficient milling of multigrain blends.Industrial relevance textMultigrain milling could be a way to improve the milling quality and performance of some cereals like triticale, hulled oat and hulled barley. Blending these cereals with wheat in different ratio followed by milling with roller mill can result in multigrain flours with different extraction rate and functional profile. Multigrain flours or some mill streams can be used for obtaining particular baked products.     

Enrichment of β -glucan in Oat Bran by Fine Grinding and Air Classification

Oats contain soluble dietary fiber, a major component of which is β -glucan. Oat bran is an oat dry milling fraction enriched in β -glucan. Our objective was to optimize β -glucan enrichment from oat bran by an inexpensive method. The defatted oat bran was ground 1×9,000, 1×14,000, or 3×14,000 rpm in a pin mill. Analysis of β -glucan for fine and coarse fractions for each milling speed indicated the highestβ -glucan content was obtained in fractions larger than 30 μ m from 3×14,000 rpm. This fraction accounted for 393 g/kg of defatted oat bran, and it contained 188 g/kg β -glucan and 302 g/kg protein. With further fractionation of this fraction by sieving, it was observed that fractions of particle size greater than 90μ m contained 200 g/kg β -glucan and less than 100 g/kg of starch. The enriched β -glucan fraction was obtained in good yield and has commercial potential as a food ingredient or for further processing.     

小麦粉破损淀粉含量的影响因素

分别以软、硬麦为原料,采用在正常生产情况下改变工艺条件并在线取样的方法,取得多组不同样品,样品处理后分别测定破损淀粉含量,研究影响小麦粉淀粉破损的重要工艺因素。研究结果表明：硬麦加工后淀粉破损率高,而软麦则相对较低,硬麦粉的淀粉破损率较软麦粉高出20%左右;面粉越细则淀粉破损率越高;研7磨道数越多,研磨强度越大,淀粉破损越严重;齿辊所造成的淀粉破损程度要比光辊为重,但差距不是很大;撞击机在正常生产时对淀粉破损影响较小,如反复撞击也会使破损淀粉增加,但其影响程度较研磨强度缓和。     

Modifications in the physicochemical properties of flour “fractions” after Pulsed Electric Fields treatment of thermally processed oat

This research aimed to investigate the physicochemical properties of thermally processed oat flour (TPOF) “fractions” (Supernatant, Top/S1, Middle/S2, Bottom/S3) after Pulsed Electric Fields (PEF) treatment of TPOF at 2 and 4 kV/cm between 50 and 451 kJ/kg. Supernatant from PEF-treated TPOF displayed a generally higher β-glucan content than untreated TPOF. No major changes were observed in chemical composition (in terms of total starch, protein, and fat contents) amongst “fractions”. However, S1 obtained from PEF-treated TPOF exhibited an increase in particle size, while both gelatinisation enthalpy and percent relative crystallinity were significantly lower compared to untreated counterpart. S1 from PEF-treated TPOF at 422–451 kJ/kg also manifested severe changes in granule morphology. S2 exhibited the highest gelatinisation enthalpy and S3 registered the least degree of observed changes in particle size. Findings of this study suggest the potential of PEF treatment application to produce oat “fractions” with varying physicochemical properties.Industrial relevanceThis study provides indispensable scientific information that could be utilised to further investigate industrial production of customised fractionation of oat flour with targeted physicochemical properties through PEF treatment. This opens new opportunities to strategically diversify the range of oat flour ingredients based on their targeted unique properties in the food industry.     

球磨改性对小米全粉理化特性及其面条品质特性的影响

小米兼具营养价值与药用价值,为提高小米的附加值和小米面条的加工品质,本实验利用球磨技术对小米全粉进行改性处理,探究不同球磨处理时间（0.5、1、2、4、6、8 h）对小米全粉营养成分、水合特性、糊化特性、流变特性、结晶结构及面条品质的影响,并分析部分理化性质与面条品质的相关性。结果表明,随着球磨时间延长,小米全粉的结晶结构破坏较明显,损伤淀粉质量分数显著增加,直链淀粉质量分数不断减少（除8 h外）,面粉亮度由77.27升至81.37。同时,球磨处理使小米全粉峰值黏度、谷值黏度和最终黏度均显著上升（P＜0.05）,分别由1 478、665 Pa·s和1 384 Pa·s提升至3 271（球磨1 h）、982 Pa·s（球磨2 h）和2 199 Pa·s（球磨2 h）,同时使水合特性（持水力、膨润力）显著提升（P＜0.05）。当球磨时间为4 h时,面团的凝胶网状结构愈发均匀致密,制作的小米面条质构、蒸煮品质均最佳。相关性分析结果表明,面条质构特性（弹性、胶黏性、咀嚼性）、感官品质（色泽、外观、黏性）与直链淀粉质量分数呈极显著负相关（P＜0.01）,与损伤淀粉和支链淀粉质量分数整体上呈极显著正相关（P＜0.01）。面条的蒸煮品质（断条率）与直链淀粉质量分数呈极显著正相关（P＜0.01）,与损伤淀粉和支链淀粉质量分数呈极显著负相关（P＜0.01）;且糊化黏度与面条品质相关性也较强。综合分析,球磨技术对小米全粉的改性处理可用于生产较高品质的小米面条。