不同粒径黑果枸杞粉体的理化性质分析

试验研究分析不同粒径和粉碎时间的黑果枸杞粉体的物化特性以及多糖、总酚和花色苷含量的变化,并结合粒度和扫描电子显微镜分析进行直观说明。使用高速粉碎机将干黑果枸杞粉碎,通过标准筛得到不同粒径的黑果枸杞粉体进行物化性质研究。结果表明,黑果枸杞经过粉碎处理后,色度、粉体流动性、复水比、持水性和松密度随粒径减小而降低;复水比和持水性随粉碎时间的延长而升高。随着粒径的减小,水分与膳食纤维含量逐渐降低,蛋白质和灰分含量逐渐升高,粗脂肪含量于120~200筛目间达到最大值为8.56%,随后含量降低;粉体中多糖含量逐渐增加,花色苷含量先增加后减小,于120~200筛目间达到最大值为24.30 mg/L。随着粉碎时间的延长,蛋白质含量与灰分逐渐降低,膳食纤维与粗脂肪含量逐渐升高,差异性显著（p<0.05）;粉碎时间在60 s时,200目筛下物多糖含量最高为152.47 mg/mL;花色苷含量逐渐下降;不同粒径和粉碎时间对粉体中总酚含量变化影响不显著（p>0.05）。对黑果枸杞进行粉碎处理得到不同粒径的粉体,其具有不同的物化性质,为黑果枸杞深加工产品的开发提供数据依据。     

菜籽粕后脱皮工艺研究

以预榨浸出后的菜籽粕为原料,通过对菜籽粕粉碎、筛分及风选,将菜籽粕中的皮进行分离,以提高菜籽粕中的蛋白含量,对其中影响较大的筛孔目数进行了选择与确定,试验得出:粉碎菜籽粕过40目筛时筛下物经风选得到的产品蛋白含量较高,为44%;此条件下产品总得率为28.3%。得到的菜籽粕可作为进一步生产菜籽浓缩蛋白的原料。     

机械分离富集小麦麸皮中糊粉层的研究

小麦麸皮是小麦加工中重要的副产物,其中糊粉层含有大量对人体健康有益的功能物质。本试验研究了干法机械分离麸皮中糊粉层的工艺。首先对小麦麸皮进行预粉碎及筛分分离处理,降低尺寸并去除部分胚乳,再将大于425μm(40目)的小麦麸皮投入分级式冲击磨进行粉碎。粉碎后的小麦麸皮被筛分分离成B1(425μm)、B2(180~425μm)、B3(100~180μm)、B4(100μm)组分。选定总磷含量作为糊粉层标识物,考察该工艺下分级式冲击磨刀片线速度、分级轮转速及进料速度对各分离组分总磷含量的影响。结果表明:当刀片线速度36 m/s、分级轮转速2 800 r/min、进料速度900 g/h条件下,B3组分的总磷含量高达(18.46±0.51)mg/g,糊粉细胞结构完整,糊粉层含量高达65.30%,小麦麸皮各结构层分离效果明显。     

金针菇超微粉体物理特性及其制备工艺优化研究

研究了不同粒径金针菇超微粉的物理性质,并以325目筛通过率为考察指标,对金针菇超微粉碎工艺进行了优化。结果表明,超微粉碎可以显著提高金针菇粉体流动性、膨胀力、容积密度、持水力和多糖溶出率。在初始温度25℃,金针菇粉含水量6%,进料目数60目,磨介数量100%,粉碎时间7 min条件下,金针菇微粉得率可达69.74%。金针菇超微粉可广泛应用于保健食品和药品行业。     

小麦麸皮粉体的电学性质初探

研究了经过粉碎、筛分后的麦麸粉体的电学特性。小麦麸皮经振动研磨20 min后,颗粒最为分散,将此时获得的麦麸颗粒进行高频振动筛分,获取3种不同粒径、结构和组成的麦麸粉体。通过电晕给电和摩擦起电两种方式使得麦麸颗粒带电,结果表明:在两种给电方式下,粒径在45～75μm的麦麸颗粒带电效果均最好。在电晕给电方式中,当电压达到46 kV时,3种麦麸颗粒所带电荷出现明显差异。对于摩擦起电,聚四氟乙烯对于3种麦麸颗粒的摩擦起电效果均最好,可以作为摩擦起电的管道材料。经过初步的探索研究,基于不同的荷质比,麦麸粉体可以通过高压静电场分离得以分离。     

国产小麦品种麸皮结构层的定性和定量分析方法

选取6种代表性中国小麦,对麦麸结构层进行手工剥离、显微观测和特征组分分析,从而建立国产麦麸结构层的定性和定量分析方法。结果表明,国产小麦中麸皮的平均比例为18%,外果皮、中间层和糊粉层分别占22%、31%和47%;通过光学和荧光显微镜可定性判定麦麸结构层;麦麸中间层中烷基间苯二酚(ARs)的含量达11.9 mg/g,分别是外果皮和糊粉层中含量的110倍和230倍,而糊粉层中总磷的平均含量为28.7 mg/g,超过外果皮和中间层中含量的20倍。因此,ARs和磷可分别作为中间层和糊粉层的标示物,外果皮可通过计算获得。结合显微观测和标示物定量的方法,可实现全麦产品中麦麸及其结构层的添加量的快速分析。     

利用啤酒糟制备高品质饲料蛋白

通过刀片粉碎和筛分技术对啤酒糟进行预处理,对筛下物进行球磨处理、固态酶解和有益微生物发酵,可以显著提高啤酒糟的饲用品质,制备高品质饲料蛋白。啤酒糟经刀片粉碎后过60目筛,筛下物粗蛋白含量达到38.8%,粗纤维含量降低到1.89%,实现蛋白-纤维的初步富集分离。对筛下物球磨后,经纤维素酶、木聚糖酶和蛋白酶混合固态酶解和产朊假丝酵母JX-09固态发酵之后,其粗蛋白含量达到45.17%,比啤酒糟原样提高了59.6%,多肽含量从0.68%提高到5.21%,蛋白体外消化率从53.7%提高到61.8%,水解氨基酸总量达到42.18%,比啤酒糟原样提高了60%,必需氨基酸总量达到17.3%,比啤酒糟原样提高了60%,粗纤维含量达到1.66%,比啤酒糟原样降低了89%。     

不同麸粉粒度及添加量对馒头品质和营养组分的影响

以小麦麸为原料,将其粉碎后添加到精粉中,并对添加麸粉的面粉制品(馒头)的营养组分进行了研究,旨在为改善粗纤维摄食量、增强人体健康提供一定数据参考。将粉碎后的小麦麸过80、120、200目筛,得到粒度不同的小麦麸粉。再分别将不同粒度的小麦麸粉按10%、20%、30%比例加入到特制一等粉中,制作麸粉含量不同的馒头,并对其进行理化指标的测定及感官评价。结果表明:过120目筛添加10%麸粉的样品中蛋白质及粗脂肪含量均最高,且与纯面粉含量有显著性差异(p0.01);添加小麦麸粉后灰分含量均高于精粉。经感官指标和理化指标综合分析,过200目筛添加10%麸粉的馒头口感松软不粗糙、有浓郁的麦香味,且粗纤维的含量与空白相比呈极显著差异(p0.001)。     

软水蓼不同目数超微粉体溶出物的化学成分分析

为分析软水蓼不同目数粉体溶出物的化学成分。采用超高效液相色谱-四级杆飞行时间质谱(UPLC-Q-TOF/MS)对软水蓼不同目数粉体化学成分进行初步分析。结果表明:软水蓼不同目数粉体的体积粒径大小随目数增加而降低;面积平均粒径从50目下降至300目时最低,再逐渐增加;粉体颗粒表面随目数增加越来越光滑,原药材特征越来越不明显;不同目数粉体溶出物中分离鉴定出17个化合物,其中黄酮类化合物9个、苯丙素类5个、有机酸、多糖及鞣质各1个,其中苯丙素类化合物Vanicoside C在200目和300目粉体中没有检测出;黄酮类化合物的峰面积值从过50目筛的粉体逐渐升高,在120目出现较高的峰面积值,随后从200~300目逐渐降低,再到500目时呈逐渐升高趋势,其中槲皮苷的相对峰面积值最高为47.11%;苯丙素类化合物峰面积值从50目下降至300目最低值,随后呈上升趋势,其中Vanicoside B相对峰面积值最高为47.79%,为明确活性化学成分作用机制及药效物质基础的阐明提供了重要依据。     

不同粉碎粒度对大麦苗粉体品质和加工特性的影响

以100目、200目、300目、500目和800目大麦苗粉为原料,考察了不同粉碎粒度对大麦苗粉体品质和加工特性的影响。结果表明:300目和500目粉碎对粉体色泽保持效果最好;100目、200目粉体流动性较好,更有利于压片成型;100目粉体持水力、膨胀力最强;200目粉体持油力最强,为1.42 g/g;800目粉体水溶性指数(WSI)最高,为20.2%;100目粉体最难吸湿,吸湿率为12.68%;100目粉体对DPPH自由基的清除率最高,为84.71%。300目和500目粉体适宜制备固体饮料或作为食品配料添加到其他食品中,100目、200目粉体适宜进行片剂、胶囊等剂型产品开发,800目粉体适宜进行可溶性功效成分提取。研究为不同大麦苗产品生产中粉碎粒度的选择提供一定的指导和借鉴。     

Triboelectric separation of aleurone cell-cluster from wheat bran fragments in nonuniform electric field

Nonuniform electric field (NUEF) was designed to separate aleurone cell-cluster from wheat bran fragments after tribocharging in a polytetrafluoroethylene tube. After triboelectric separation (TS), the ultrastructure, composition and particle size distribution of the bran fragments were studied. The results showed that, the positive-NUEF had a higher efficiency than the negative-NUEF for the enrichment of aleurone cell-cluster. After the first step of TS in positive-NUEF, about 1.5-time more aleurone cell clusters and 1.3-time more testa particles were deflected to the positive electrodes, while the outer pericarp fragments were enriched in the middle fraction. No obvious difference was found between the particle sizes of the electrode-fraction and middle-fraction, suggesting that the difference in particle size was not the main reason for the charging diversity. After two steps of TS in positive-NUEF, the proportion of aleurone cells increased from 51% to 78% with a total yield of 42%, indicating that the nonuniform electric field was effective for the enrichment of aleurone particles.     

The phenolic acid and polysaccharide composition of cell walls of bran layers of mature wheat (Triticum aestivum L. cv. Avalon) grains

The purpose of this study was to examine the carbohydrate and phenolic‐ester composition of cell walls in wheat bran layers. Four defined layers of wheat bran were separated manually from mature grains of wheat (Triticum aestivum L. cv. Avalon) to give samples of beeswing bran (outer pericarp), cross cells, testa + nucellar epidermis and aleurone cells. The cell‐wall material from each layer, and from a sample of intact bran, was analysed for carbohydrates and wall‐bound esterified phenolic acids. The cell‐wall material of intact bran was rich in arabinose and xylose with significant quantities of glucose and uronic acid and a relatively small amount of galactose and mannose. The varying ratios of arabinose:xylose in cell walls of isolated bran layers indicated that the heteroxylans had tissue‐specific substitution patterns. HPLC analysis of phenolic acids identified significant amounts of esterified ferulic acid and 8‐8′‐ (aryltetralin form), 5‐8′‐, 5‐5′‐, 8‐0‐4′‐ and 5‐8′‐(benzofuran form)‐dehydrodiferulic acids in the isolated cell walls. Ferulic acid was highly concentrated in the aleurone layer, whereas dehydrodiferulates were concentrated in the beeswing bran and cross cells. The role of phenolic cross‐linking is discussed in relation to the architecture of the cell walls of wheat bran and to processing implications. Copyright © 2005 Society of Chemical Industry     

EFFECT OF PARTICLE SIZE ON THE WATER SORPTION PROPERTIES OF CEREAL FIBERS1

Six particle size fractions were prepared by grinding and sieving stabilized hard red wheat bran, oat fiber, and corn bran. Water adsorption indices (WAI's) and effective diffusion coefficients (D_eff) were measured for all size fractions. WAI's of wheat bran decreased with particle size. WAI's of oat bran increased as particle size decreased and the WAI's of corn bran fractions did not vary as much as the other fibers. The D_eff's of wheat increased, of oat decreased, and of corn were about the same as the particle size decreased. The wheat D_eff was less than that of corn which was less than that of oats. Monolayer moisture content and bulk moisture content at high A_w were determined from moisture sorption isotherms measured on the smallest particles. There was no difference in the monolayer moistures but both corn and wheat brans adsorbed much more water at high A_w than did the oat bran. Effect of particle size on water sorption and, by inference, some types of functionality cannot be generalized and must be determined for each type of fiber.     

超微粉碎制备蜜柑果皮全粉研究

以蜜柑果皮为原料,以不同干燥方式干燥果皮,运用超微粉碎方法制成粉体,通过测定粉体的粒度分布情况、持水力、持油力及色度值等指标,对常压干燥、真空干燥及冷冻干燥等不同干燥方式进行比较,得出常压干燥方式最佳。并利用响应曲面法研究果皮超微粉碎工艺,以粗粉粒径、转速及粉碎次数为自变量,比表面积为响应值,研究各自变量及其交互作用对果皮超微粉碎效果的影响,确定最佳超微粉碎工艺为：粗粉粒径60～80目、转速16000r/min、粉碎次数3次,此工艺条件下,得到的比表面积为0.246m2/g。     

彩色小麦的理化特性及麸皮粉的品质评价

目的研究彩色小麦和普通小麦的理化特性、营养组成及小麦皮层和胚乳中淀粉粒的结构形态和类型,为进一步了解彩色小麦的特性提供理论依据,为彩色小麦的营养加工奠定良好的基础。方法采用国标方法,对彩色小麦的理化指标和营养组成进行综合分析;采用扫描电子显微镜方法观察分析彩色小麦的皮层和胚乳中淀粉粒的结构形态和类型。结果彩色小麦在千粒重、容重等物理特性方面低于普通小麦,且彩色小麦籽粒的长宽比大,没有普通小麦籽粒饱满。在营养组分方面,绿麦3104、紫麦3202、黑麦3201的蛋白质含量分别比普麦烟农19高29.5%、24.4%、21.3%;湿面筋含量分别比普麦烟农19高29.6%、19.0%、17.0%;粗脂肪含量分别比普麦烟农19高31%、10.4%、22.2%。通过扫描电镜对小麦皮层结构分析发现彩色小麦糊粉层中含有大量的糊粉颗粒,集中了小麦籽粒大部分的营养物质。干法制备的麸皮粉,随着碾磨道数的增加,其灰分含量呈升高趋势,出粉率和白度呈降低趋势。结论彩色小麦在营养组成方面与普通小麦相比有很大优势,麸皮粉的品质特性与普通小麦相似,但彩色小麦的胚乳淀粉粒的形态和类型与普通小麦存在很大差异。     

超微粉碎对小麦麸皮物理性质的影响

为研究超微粉碎对小麦麸皮持水力,膨胀力、持油力、阳离子交换能力、可溶性膳食纤维(SDF)含量等性质的影响,将小麦麸皮原粉进行超微粉碎处理得到小麦麸皮微粉,比较不同粒度的的小麦麸皮样品的性质变化.结果表明:超微粉碎后小麦麸皮的持水力、膨胀力、阳离子交换能力及SDF百分含量较原粉有较大程度的提高;持油力略有下降.其中微粉C...     

Effects of Particle Size and Breadmaking on Physiological Responses of Meal-Fed Rats to AACC Wheat Bran

Adult rats were meal-fed diets containing 20% AACC certified hard red spring wheat bran (as received, ground, incorporated into bread) for 12 days to determine the short-term processing-induced effects on gastrointestinal function and serum lipids. Fecal nitrogen, fecal fat, transit time and serum triglyceride levels were influenced by the consumption of wheat bran, but not by the grinding or breadmaking procedures. Reduction of bran particle size decreased dietary hemicellulose and reduced fecal bulk as well as defecation frequency. Incorporating bran into bread reduced dietary neutral detergent fiber (NDF), reduced intestinal passage rate of the ground wheat bran and decreased degradation of dietary fiber components in the unground wheat bran.     

不同粒径米糠对面团特性及饼干品质的影响

富含营养的米糠添加到饼干中成为营养饼干开发的重要方向。为评价不同粒径米糠对面团特性及饼干品质的影响，该研究制备了4种不同粒径（50、100、150、200目）米糠原料，探究了其对面粉粉质特性、面团流变特性、饼干质构特性和感官品质影响，并从面筋蛋白巯基含量、谷蛋白大分子聚合物（Glutenin Macropolymer，GMP）含量和面团微观结构变化等角度初步分析了其影响机制。结果表明，随着米糠粒径的减小，面团的稳定时间、形成时间降低，粘弹性模量增大；减小米糠粒径后可提高饼干质构特性，表现为硬度和咀嚼性降低；200目米糠饼干的模糊数学感官评分最高，达77.02分。添加米糠后，面筋蛋白巯基含量随米糠粒径减小而逐渐增大，GMP含量则逐渐降低，面筋网络结构逐渐弱化，表明降低米糠粒径促进了面筋蛋白二硫键的断裂，GMP的解聚，以及面筋网络强度的降低，从而改善了米糠饼干品质。研究结果为推动米糠在饼干等焙烤食品中的应用提供了理论指导。     

Effect of aleurone cell damage on wheat fibre values as determined by the neutral detergent technique

The extent of aleurone cell damage suffered by wheat during grinding has been shown to have a profound effect upon its “neutral detergent fibre” value. Sound aleurone cells have been found to retain much of their contents during the fibre determination, while damaged cells retained none. The implication of these results upon previous work is discussed. Comparisons of NDF values of different wheat or bran samples are only meaningful when their preparation for testing has involved identical conditions of grinding.     

不同粒度区间小麦粉对半干面品质的影响

研究了四个不同粒度区间小麦粉对半干面品质的影响。结果表明,不同粒度区间的小麦粉之间的品质表现差异性显著(p<0.05),180~200目粒度区间小麦粉的粗蛋白含量、湿面筋含量和面筋指数均高于其他粒度区间小麦粉;破损淀粉和灰分含量随粒度减小逐渐增加;140~160目区间小麦粉的粉质质量指数最大,稳定时间最长,弱化值最小;140~200目区间小麦粉的吸水率差异并不显著。随小麦粉粒度减小,半干面的白度、吸水率、蒸煮损失率逐渐增加;140~160目区间小麦粉制作的半干面,其硬度最大,咀嚼性最好;160~180目区间小麦粉制作的半干面,其拉伸性能最好;180~200目区间小麦粉制作的半干面,其深层结合水比例最高,回复性、弹性、黏聚性表现最好,感官评分最高,适合制作半干面。