热风干燥条件对马铃薯全粉糊化品质的影响

为了改善马铃薯脱水制品的干燥工艺,该文以薄层干燥试验为基础,研究了不同热风温度(40、50、60、70、80、90℃)、风速(0.5、1.0、1.5、2.5、3.5 m/s)和切丁长度(2.5、5、10、15 mm)对马铃薯全粉的糊化特性的影响。采用扫描电子显微镜和差示扫描量热仪对马铃薯全粉的微观结构和糊化特性进行分析,并测定了其吸水性。研究表明,糊化焓值可以表征马铃薯全粉的糊化水平,焓值越高,糊化水平越低;糊化起始温度的范围为62.31~64.96℃,终止温度的范围为70.16~74.19℃,比纯淀粉制品糊化温度高;高于糊化温度进行干燥时,淀粉不会完全糊化;0.5~2.5 m/s风速干燥的样品糊化焓值没有显著差异(P0.05),3.5 m/s干燥的样品焓值显著小于其他风速干燥样品;马铃薯全粉焓值随切丁长度增大而显著减小(P0.05);不糊化样品吸水性没有显著差异(P0.05),吸水性随糊化程度的增强而显著增强;热风干燥条件为温度70℃,风速1.0 m/s和切丁长度10 mm时,马铃薯全粉的糊化程度较低。研究可为热风干燥制备未糊化的马铃薯全粉提供理论基础。     

不同中薯系列马铃薯淀粉组成与理化性质的差异分析

为分析不同品种马铃薯淀粉组成与理化性质的差异,本研究以15个不同品种中薯系列马铃薯为原料提取淀粉,并对其组成和理化性质进行了检测及相关性分析。光学显微镜和扫描电镜结果表明,马铃薯淀粉颗粒的粒径分布范围广,颗粒形貌存在差异,小颗粒多为卵圆形,大颗粒多为椭圆形、拉长形以及不规则形。不同马铃薯淀粉的理化性质存在显著差异,其溶解度、膨润力范围分别为25.92%~28.74%,4.90~6.26 g·g^-1;糊化初始温度(T_o)、峰值温度(T_p)、终止温度(T_c)、糊化焓值(ΔH)范围分别为61.44~65.55℃、64.49~68.69℃、67.87~72.54℃、7.21~13.49 J·g^-1;峰值黏度、衰减值、回生值范围分别为2 499.3~3 220.4、514.0~2 218.4、401.0~884.1 BU。相关性分析结果表明,马铃薯淀粉中磷含量与峰谷黏度呈显著正相关,与溶解度呈显著负相关;平均粒径D[4,3]与短程有序参数1 045/1 022 cm^-1 和1 022/995 cm^-1均呈显著正相关;T_o与峰值黏度呈显著负相关;糊化温度与峰值黏度和崩解值均呈显著负相关,与峰谷黏度、最终黏度和回生值均呈显著正相关。本研究结果可为中薯系列马铃薯淀粉在食品加工中的应用提供科学依据。     

垄沟集雨覆盖对旱作马铃薯块茎淀粉颗粒形态、颗粒分布及糊化特性的影响

为探讨垄沟集雨覆盖栽培对旱作马铃薯块茎形成过程中淀粉颗粒形态、颗粒分布及糊化特性的影响,以马铃薯栽培品种青薯9号为材料,设置全膜双垄(M2)和地膜垄作(M1)覆盖栽培模式,以露地平播为对照(M0),采用扫描电镜、激光粒度仪、粘度分析仪,测定马铃薯块茎形成过程中淀粉的颗粒形态、分布及糊化特性指标。结果表明,从块茎发育全程来看,全膜双垄覆盖栽培模式下马铃薯块茎淀粉颗粒的平均粒径、峰值粘度、低谷粘度及最终粘度整体较高;地膜垄作覆盖栽培模式下马铃薯块茎淀粉颗粒的离散度、崩解值、回生值整体较高;各栽培模式间马铃薯块茎淀粉颗粒形态、糊化温度无显著差异;马铃薯淀粉颗粒的平均粒径与各阶段粘度呈显著正相关,与糊化温度呈显著负相关,与崩解值、回生值无显著相关性;马铃薯淀粉颗粒的离散度与淀粉的糊化特性各指标均无显著相关性。综上,全膜双垄覆盖栽培模式所产生的淀粉品质较好。     

旱作区抗病优质高效马铃薯新品种(系)筛选试验初报

为筛选出适宜天水市旱作区种植的优质马铃薯品种,解决马铃薯生产中存在的品种单一、抗病、优质专用品种相对缺乏及产量水平相对低下等问题。以当地主栽马铃薯品种陇薯6号为对照品种,对引进的11个马铃薯品种(系)进行了品种比较试验。结果表明,DSS-35折合产量最高,为35 704.05 kg/hm2,较对照品种陇薯6号增产15.23%;京张薯1号、陇薯20号折合产量较高,分别为34 784.40、34 340.85 kg/hm2,较对照品种陇薯6号分别增产12.26%、10.83%。这3个马铃薯品种(系)综合性状优良、商品薯率较高,较抗病毒病和环腐病,块茎晚疫病发病较轻,适宜在天水市旱作区及同类生态区种植。     

不同工艺马铃薯粉物化特性及氨基酸组成比较

为明确马铃薯渣粉、以马铃薯渣为原料的马铃薯复配粉与马铃薯全粉、马铃薯冻干粉以及高筋小麦粉成分和性质的差异,本研究对其基本成分、物化及感官特性、氨基酸组成进行比较,并以FAO/WHO氨基酸模式为评价标准,采用模糊识别法、氨基酸比值系数评分法、氨基酸评分、必需氨基酸指数、生物价和营养指数多种方法对各样品蛋白的营养价值进行全面评价及对比。结果表明,在样品吸水性方面,马铃薯全粉马铃薯渣粉马铃薯复配粉马铃薯冻干粉高筋小麦粉;氨基酸比值系数最高为马铃薯复配粉(100.00),其次是马铃薯全粉(81.00)和马铃薯薯渣粉(72.25),马铃薯冻干粉和高筋小麦粉最低(68.89);必需氨基酸指数和生物价最高为马铃薯复配粉和马铃薯渣粉,其次为马铃薯冻干粉和马铃薯全粉,高筋小麦粉最低;营养指数从高到低依次为高筋小麦粉、马铃薯全粉、马铃薯冻干粉、马铃薯渣粉及马铃薯复配粉。马铃薯复配粉的成本低,吸水性、加工性能等优于马铃薯全粉,但营养指数暴露出马铃薯复配粉蛋白含量较低的缺陷,后续的加工过程中可以通过向马铃薯复配粉中添加营养价值较高且与马铃薯蛋白氨基酸组成互补的蛋白质,弥补马铃薯复配粉蛋白含量较低的缺陷,这为解决薯渣利用问题提供了新思路。     

拔节期追氮对鲜食糯玉米粉糊化和热力学特性的影响

以苏玉糯1号、苏玉糯5号和渝糯7号为材料,研究了拔节期追氮量（N 0、150和300 kg/hm2）对鲜食糯玉米粉糊化和热力学特性的影响。结果表明,随着拔节期追氮量的增加,峰值黏度和崩解值下降,糊化温度升高,而谷值黏度、终值黏度和回复值呈先降后升趋势; 热力学特征参数中,回生值、终值温度、糊化范围和峰值指数受拔节期追氮量影响较小。原样品热焓值和回生后样品热焓值均表现为随着拔节期追氮量的增加呈先降后升趋势。糊化和热力学特征值对拔节期追氮量的响应不同品种间存在差异。鲜食糯玉米粉的理化特性存在显著的基因型差异,峰值黏度以苏玉糯5号最高,苏玉糯1号最低; 峰值温度苏玉糯1号和苏玉糯5号无显著差异,但均高于渝糯7号; 热焓值、回生值、糊化范围和峰值指数不同品种间相对稳定。相关分析表明,峰值黏度与原样品热焓值和峰值指数呈显著正相关; 崩解值与糊化温度及转变温度,回生值与淀粉的终值黏度和回复值呈显著负相关。在本试验条件下,拔节期追氮总体上使糯玉米食用品质降低,其中以苏玉糯5号在不追氮处理下的糊化和热力学特性较优,即峰值黏度、崩解值和热焓值较高,回生值较低。     

不同来源淀粉特性对水晶皮质构品质的影响

为了研究原料淀粉特性对水晶皮质构品质的影响,该文选用小麦、玉米、马铃薯、木薯、绿豆5种淀粉原料,测定并分析淀粉颗粒特性、破损淀粉含量、糊化特性与水晶皮的透明性、质构等品质的关系。结果表明:不同来源的淀粉制作水晶皮品质差异较大,小麦淀粉皮品质最好,其次是马铃薯、木薯、玉米淀粉皮,绿豆淀粉皮品质最差。淀粉颗粒特性、破损淀粉含量与水晶皮品质指标密切相关。平均粒径、膨胀度越大,水晶皮亮度、透明性越好;适宜的破损淀粉含量能够保证水晶皮较好的综合质构品质;淀粉的糊化特性与水晶皮品质指标之间存在显著相关性;淀粉峰值粘度和衰减值与水晶皮透光率呈极显著正相关。谷值粘度、最终粘度、回生值与水晶皮硬度、弹性、咀嚼性、剪切力呈极显著正相关,起始糊化温度与水晶皮品特性相关性不显著。因此,在水晶皮制作进行原料选择时,可以测定淀粉粒径、膨胀度、峰值粘度、衰减值来预测淀粉皮亮度与透光率;测定淀粉破损淀粉含量、谷值粘度、最终粘度、回生值来预测淀粉皮适口性等品质特性。该文旨在为加工水晶产品原料选择以及品质改善提供基本的理论支撑。     

陇中旱作区加工型马铃薯新品种筛选试验初报

陇中旱作区马铃薯种植历史悠久,马铃薯产业已成为当地的主导产业。为筛选出陇中旱作区优质抗旱的淀粉加工型和全粉加工型马铃薯新品种。以陇薯3号为对照品种,在陇中旱作区对引进适宜不同生态区域种植的8个加工型马铃薯新品种进行筛选比较试验。结果表明,陇薯16号、陇薯17号、甘农薯9号这3个品种生育期长(120～125 d),为晚熟或中晚熟品种;出苗率高,植株生长旺盛,主茎数多,大中薯率均高于80%;薯形为圆形或长卵圆形、薯皮光滑、芽眼浅、食味优(蒸煮食味综合评分分别为7.00、7.50、6.63分);干物质含量高,分别为253.0、243.2、249.0 g/kg,分别较对照品种陇薯3号增加6.0、-3.8、2.0 g/kg;还原糖含量分别为2.70、1.40、1.10 g/kg;折合产量分别为29 670、30 855、31 055 kg/hm2,分别较对照品种陇薯3号增产5.62%、9.84%、10.56%,可作为陇中旱作区全粉加工型品种推广种植。由于陇薯16号淀粉含量高达232.0 g/kg,也可作为陇中旱作区优质的高淀粉加工型品种进行推广。     

陇薯6号脱毒种薯繁育技术

淀粉与全粉加工兼用型马铃薯新品种陇薯6号(原代号L9408-10)由甘肃省农业科学院于2003年育成,该品种具有抗病、高产、高淀粉、低还原糖、适应范围广等优点.     

内蒙古马铃薯脂肪酸谱及其综合营养评价

对产自内蒙古自治区的480份马铃薯样本进行脂肪酸谱的识别与量值监测,同时利用主成分分析对马铃薯脂肪酸组成进行综合营养价值评价。结果表明,内蒙古阴山北麓、阴山南麓和大兴安岭东南区马铃薯粗脂肪及含量差异显著(p0.05);共检测出11种游离脂肪酸,不同品种马铃薯棕榈酸、亚油酸、亚麻酸、十七碳酸、油酸含量差异显著(p0.05);主成分分析中,前3主成分累计贡献率达80%以上,基本概括了马铃薯脂肪酸组成的基本信息;综合得分显示,游离脂肪酸组成比例分值大小排序为克新一号后旗红费乌瑞它冀张薯226大白花夏波蒂青薯9号;膳食分析显示,内蒙古马铃薯脂肪酸Σn-3/Σn-6值为0.28～0.44,可以同时满足国际粮食与农业组织(FAO)和世界卫生组织(WHO)推荐的最佳膳食比。     

Impact of Waxy,Partial Waxy,and Wildtype Wheat Starch Fraction Properties on Hearth Bread Characteristics

Thirteen different wheat cultivars were selected to represent GBSS mutations: three each of wildtype, axnull, and bxnull, and two each of 2xnull and waxy. Starch and A‐ and B‐granules were purified from wheat flour. Hearth bread loaves were produced from the flours using a small‐scale baking method. A‐granules purified from wildtype and partial waxy (axnull, bxnull, and 2xnull) starches have significantly higher gelatinization enthalpy and peak viscosity compared with B‐granules. A‐ and B‐granules from waxy starch do not differ in gelatinization, pasting, and gelation properties. A‐ and B‐granules from waxy starch have the highest enthalpy, peak temperature, peak viscosity, breakdown, and lowest pasting peak time and pasting temperature compared with A‐ and B‐granules from partial waxy and wildtype starch. Waxy wheat flour has much higher water absorption compared with partial waxy and wildtype flour. No significant difference in hearth bread baking performance was observed between wildype and partial waxy wheat flour. Waxy wheat flour produced hearth bread with significantly lower form ratio, weight, a more open pore structure, and a bad overall appearance. Baking with waxy, partial waxy, and wildtype wheat flour had no significant effect on loaf volume.     

Physicochemical,Textural, and Nutritional Characterization of Mexican Rice Cultivars

The physicochemical properties, textural properties, and starch digestibility of rice cultivars grown in Mexico were evaluated. Variations existed in grain dimensions, and the rice grains were classified as medium, long, and extra long. Huimanguillo had the highest amylose content (30.4%), and A06, A92, A98, and Champoton presented the lowest amylose content (24.3–25.2%). The protein content was 7.1–11.0% and the lipid level was 0.47–1.22% among these Mexican cultivars. Champoton showed the highest temperature and enthalpy of gelatinization, and this with A98, Culiacan, and Huimanguillo had the highest enthalpy of retrogradation. Cotaxtla had the highest pasting peak, setback, and final viscosity. The texture assessment in cooked rice showed that A06 had the highest hardness, and A96 and A98 had the highest stickiness. There was little difference in the rapidly digestible starch, slowly digestible starch, and resistant starch content of tested Mexican rice cultivars. The differences in the physicochemical properties could be used to determine the end use of these Mexican rice cultivars.     

Comparison of the physicochemical properties and pasting characteristics of flour and starch from red and white sweet potato cultivars

This research characterized flour and raw starches isolated from red and white sweet potato cultivars. Their composition, determined by proximate analysis, is typical of sweet potato cultivars. These cultivars have high amylose content (32-34%) and exhibit a Ca-type X-ray diffraction pattern. Similar gelatinization characteristics were detected for both starches with onset temperature of 67 degrees C and enthalpy of 10.5-11.0 J/g. Starches of both red and white cultivars had well-correlated (r (2) = 0.982) and high solubilization and swelling temperatures, starting at 80 degrees C. Pasting properties of the white cultivar exhibit lower tendency for retrogradation. Water and oil absorption capacities were low for both red and white flours. When parboiled, both cultivars showed improved water absorption capacity and decreased least gelation concentration. It is concluded that the white cultivar should be preferred when low retrogradation tendency is required.     

Influence of Amaranthus betacyanin pigments on the physical properties and color of wheat flours

The effect of betacyanin pigments from Amaranthus tricolor and Amaranthus cruentus on chromatic and physicochemical properties of three wheat flours was studied. Addition of Amaranthus betacyanins increased the gelatinization temperatures (T(o), T(p), and T(c)) of all wheat flours without altering their transition ranges (T(c)-T(o)). The melting enthalpies (DeltaH) were either increased or decreased depending on the types of flour and pigment. Amaranthus betacyanins decreased the peak viscosity (PV), hot paste viscosity (HPV), cold paste viscosity (CPV), setback (SB), and pasting time (PT) of all flours and increased the breakdown (BD). Texture profile analysis (TPA) showed that Amaranthus betacyanins decreased hardness, and gumminess, and increased cohesiveness of all gels, without altering adhesiveness. Chromatic investigation exhibited that A. tricolor and A. cruentus pigments imparted gels with red and orange-yellow hues with favorable color stability.     

南方馒头专用小麦粉原料选择研究

为生产高品质南方馒头,确定优质南方馒头专用小麦粉原料特性的取值范围,本研究以20种小麦粉为原料制备南方馒头,探究小麦粉的理化特性、糊化特性、拉伸特性、粉质特性对南方馒头品质的影响,通过逐步回归分析法筛选出影响南方馒头综合品质的小麦粉关联性指标,结合聚类分析得到适宜加工南方馒头的小麦粉原料关联性指标范围。结果表明,小麦粉原料的灰分、降落数值、峰值黏度、形成时间、稳定时间、弱化值、延伸度、拉伸面积、拉伸比、最大拉伸比与南方馒头品质综合得分存在显著(P < 0.05)相关性。影响南方馒头综合品质的关键指标为延伸度、形成时间和峰值黏度,适宜加工南方馒头的小麦粉参考关键指标范围为:延伸度126.00~158.00 mm、形成时间1.70~5.00 min、峰值黏度 1 027.00~1 326.00 Pa·s。小麦粉原料选择模型的建立和关键性指标范围的确定可预测南方馒头品质。本研究为南方馒头原料选择提供了依据,并可用于进一步改善南方馒头的综合品质。     

Impact of Rice Flour Cold‐Water‐Soluble Fraction Removal on Gelatinization and Pasting Properties

The influence of the cold‐water‐soluble fraction on gelatinization and pasting properties of rice flour was investigated. The cold‐water‐soluble fraction was removed by water extraction under room temperature. The gelatinization properties of untreated and treated flour were analyzed with a differential scanning calorimeter, and pasting profiles were measured with a rapid viscosity analyzer. The removal of the cold‐water‐soluble fraction resulted in the formation of a loosened starch granule structure, a morphological alteration of protein bodies, a markedly lower gelatinization temperature, and a significantly higher pasting enthalpy. The impact on paste viscosity followed different trends. In some cultivars that had lower endogenous amylase activity, the paste viscosity was greatly reduced by the removal of the cold‐water‐soluble fraction. In others, the higher level of endogenous amylase activity led to more soluble saccharides being released through starch hydrolysis. Removing the soluble fraction caused a remarkable increase in peak viscosity. The overall effect on paste viscosity of removing the cold‐water‐soluble fraction was attributed to multiple factors, involving loosening of the starch granule structure, alteration of morphology of protein bodies, and the release of saccharides by endogenous amylase activity.     

不同淀粉糊化及凝胶特性与粉条品质的关系

为了研究粉条加工过程中原料淀粉的糊化及凝胶特性对粉条品质的影响,该文对绿豆、红薯、马铃薯、大米和玉米等5种原料淀粉的糊化凝胶特性及其粉条品质进行了测定,并对淀粉糊化凝胶特性与淀粉粉条品质之间的关系进行探讨。结果表明:5种淀粉原料所制的粉条中,绿豆粉条的品质是较好,其次就是马铃薯粉条和红薯粉条,大米粉条和玉米粉条的品质较差;淀粉的糊化特性与粉条品质之间具有显著相关性,按显著程度的大小(P值大小)依次是:峰值黏度谷值黏度衰减值回生值、最终黏度;淀粉凝胶的硬度、弹性、黏性和咀嚼性对粉条品质的影响较大,按显著程度的大小(P值大小)依次是:硬度黏性咀嚼性弹性。在粉条加工原料选择及粉条品质改善中可以考虑用谷值黏度、回生值以及淀粉凝胶特性特征值回复性、咀嚼性和黏性作为考核衡量指标。研究结果为粉条生产中原料选择及品质改善提供参考依据。