不同粒径小米粉对面团流变特性及馒头质构特性的影响

为研究小米粉添加对面团流变特性和馒头制品质构特性的影响,分别选取不同粒径的粳性和糯性小米粉,利用损伤淀粉测定仪、快速黏度分析仪等对不同小米粉的损伤淀粉含量和糊化特性进行分析,通过流变仪测定小米面团的流变学特性,结合扫描电镜观察小米面团微观结构变化,并利用质构仪测定小米馒头的质构特性。结果表明：随着小米粉粒径的减小,多数品种小米粉（除冀谷39和汇华金米）损伤淀粉的碘吸收率增加;受直支比的影响,相同目数下,粳性小米粉的峰值黏度、谷值黏度、最终黏度和回生值较糯性小米粉大。流变学研究表明,除汇华金米和冀谷39,储能模量与损耗模量随角频率增加总体上升。扫描电镜观察发现小米粉的添加使面团结构更加松散。小米粉的添加会对馒头质构性质中硬度、咀嚼性和弹性等有一定程度的负面影响。主成分分析表明馒头咀嚼性、损伤淀粉、峰值黏度、谷值黏度、最终黏度、崩解值和回生值可作为区分粳糯品种和馒头品质特征的指标。     

有色糯性糜子理化与体外消化特性研究

以四种不同颜色糯性黄米为试验材料,黄色粳性黄米为对照,对其理化性质、糊化特性、蒸煮品质和体外消化特性进行分析。结果表明,不同颜色糯性黄米的基本成分存在显著差异;白色糯性黄米的溶解度和膨胀度最大;不同颜色糯性黄米多酚、黄酮含量差异不显著;不同颜色糯性黄米的加热吸水率、体积膨胀率及溶出率均随蒸煮温度的升高而增大;四种黄米的起糊温度、峰值黏度、破损值、最终黏度和回生值平均为78.62℃、616.88 RVU、220.88 RVU、574.00 RVU、170.63 RVU;黄色糯性黄米快速消化淀粉的含量最多,粳性黄米含有更多的RS+SDS,适合开发抗消化食品。不同颜色糯性黄米的品质特性不同,为黄米精深加工和保健产品的开发提供依据。     

鲜湿米粉品质评价及原料选择

为确定适宜鲜湿米粉加工用大米的关联性指标及阈值区间,本研究以18种大米为原料制备切条型鲜湿米粉,探讨大米主要成分质量分数、淀粉糊化特性对米粉蒸煮品质、入味性、感官品质和质构品质的影响,并利用主成分分析建立鲜湿米粉综合品质评价模型,计算米粉品质综合得分,通过逐步回归分析筛选出影响米粉综合品质的关联性指标,结合聚类分析得到适宜加工米粉的原料大米关联性指标范围。结果表明:大米的直链淀粉质量分数,淀粉糊化特性的最低黏度、最终黏度、衰减值、回生值与米粉的蒸煮品质、感官品质、质构品质显著相关(P0.05);大米主要成分、淀粉糊化特性与米粉的入味性相关性不显著(P0.05)。影响米粉综合品质的关联性指标为直链淀粉质量分数和最终黏度,适宜加工切条型鲜湿米粉的原料大米直链淀粉质量分数应大于26%,淀粉的最终黏度应大于3 852 Pa·s。     

稻米理化、食味品质指标与米饭质构品质相关性分析

为研究11种稻米品质指标(理化指标、食味品质指标和米饭质构品质指标)之间的差异,应用主成分分析方法对不同品种稻米的品质进行评价,并利用聚类分析法将其归类。结果表明:通过变异系数可以看出稻米品种对黏度、硬度品质指标的影响较大,而对水分含量、总淀粉含量的影响较小。通过主成分分析确定的3个主成分可以代替上述众多品质指标对不同稻米品种品质进行评判。主成分1主要综合了食味值和感官评价,主成分2主要综合了综合评分和外观,主成分3主要综合了直链淀粉含量和直支比。通过聚类分析将其品质划分为3大类:第I类有苏秀867、稻花香、金禾圆粒、淮稻5号、绥粳18,其品质最好;第II类有淮119、南粳5505、桃优香占、扬粳3012、武运粳32,其品质居中;第Ⅲ类是五优61。此结论可为优质稻米品种的筛选提供一定的参考依据。     

压榨型干米粉专用米关键指标的研究

为确定压榨型干米粉专用米的特征指标,文章以17种籼米为原料,运用相关分析、主成分分析、聚类分析以及逐步回归分析法探讨大米原料品质和糊化特性对干米粉食用品质和质构品质的影响。结果表明:大米原料中的直链淀粉含量、淀粉含量、脂肪含量、脂肪酸值,糊化特性中的最低黏度、最终黏度、崩解值、回生值、胶稠度,与干米粉的蒸煮品质和质构品质存在显著(P<0.05)相关性;其中影响米粉综合品质的关键性指标为直链淀粉含量、最终黏度和胶稠度;聚类分析得出的适宜加工压榨型干米粉的原料大米的直链淀粉含量应大于22%,淀粉的最终黏度应大于3963 cP,胶稠度应小于46 mm。     

压榨型鲜湿米粉条凝胶质构特性及食用品质影响因素

以压榨型鲜湿米粉条凝胶品质影响因素为研究对象,主要探讨了大米粉基本理化指标、快速黏度分析(rapid visco analyze,RVA)糊化特性、大米淀粉结晶特性对压榨型鲜湿米粉条的食用品质及其凝胶质构特性的影响。研究表明大米粉直链淀粉的质量分数与米粉条的感官得分、质构特性指标(除黏附性、弹性外)呈显著或极显著正相关(P0.05,P0.01),大米粉支链淀粉质量分数与米粉条感官得分、质构特性指标(除黏附性、弹性外)呈显著或极显著负相关(P0.05,P0.01);大米粉粗蛋白(除与恢复性呈显著正相关外)、粗脂肪质量分数与米粉条凝胶特性和食用品质相关性不显著(P0.05);X射线衍射、傅里叶变换红外光谱2种方法分析得到的结晶度RX和RI均与米粉条的凝胶特性指标和食用品质感官得分均无显著相关性(P0.05)。RVA糊化特性参数中的峰值黏度、最低黏度和最终黏度与米粉条的感官得分、质构特性指标(除黏附性、弹性外)呈显著或极显著正相关性(P0.05,P0.01);衰减值虽与感官得分、凝胶质构特性指标(除与黏附性显著负相关外)均呈一定的负相关性,但均不显著(P0.05);而回生值则与米粉条感官得分、凝胶质构特性指标的硬度、胶着性、咀嚼性、恢复性均呈极显著正相关(P0.01)。由此可见,直链淀粉、支链淀粉质量分数及RVA糊化特性参数可用来预测压榨型鲜湿米粉条的食用品质关键性指标。     

基于主成分分析和聚类分析综合评价蒸谷米的品质特性

为探讨蒸谷米的品质并建立其评价体系,本试验选取12个不同品种的稻谷原料制备蒸谷米,并对其碾磨品质、外观品质、营养品质、食味品质和糊化特性的品质指标进行测定分析,考察不同品种稻谷制得的蒸谷米各项品质指标之间的差异性。同时,采用主成分分析法和聚类分析法对蒸谷米的品质进行综合性评价并建立蒸谷米品质评价模型。结果表明,不同品种稻谷制得的蒸谷米各项品质指标之间均存在差异性（P<0.05）,且品质指标间变异系数各不相同,说明蒸谷米在不同品质性状之间呈现不同程度的变化。由主成分分析发现23个反映不同品种稻谷制得的蒸谷米品质的指标可以用6个主成分表示,其累积方差贡献率为91.083%;根据聚类分析结果可知,爆腰率、黄米粒、外观、蛋白质、崩解值、峰值黏度、最终黏度和回生值8个品质指标可以用来综合评价蒸谷米品质的优劣。12个不同品种稻谷制得的蒸谷米中,“玉针香”的品质最佳,“大粒香”的品质最差,其次为“粤丰B”。主成分分析结合聚类分析综合评价方法可为不同品种稻谷制备蒸谷米的品质评价提供参考,并为蒸谷米专用稻的选育及蒸谷米资源的开发应用奠定理论依据。     

大米原料对鲜湿米粉品质影响

试验以5种大米为研究对象,采用快速黏度仪和动态流变仪分析其糊化特性和流变学特性,结合质构和模糊感官评价法对大米制作鲜湿米粉进行品质评价。结果表明,成泰大米衰减值最小,回生值最大;胶稠度和直链淀粉含量与衰减值、回生值和最终黏度等糊化特征值存在显著或极显著相关;温度扫描和频率扫描显示各品种大米G’始终大于G’’,成泰大米G’最高,降温过程中G’上升最快,说明胶凝性最好;各品种米粉质构指标之间存在显著性差异,且综合质构和感官评价结果,选出适合做鲜湿米粉的大米原料。     

速冻汤圆专用糯米核心指标的探究

为确定适宜速冻汤圆加工专用糯米的关键性指标及指标范围,以22种糯米为原料制备速冻汤圆,探讨糯米主要成分、糊化特性对汤圆质构品质的影响,并利用主成分分析建立汤圆综合品质评价模型,再通过逐步回归分析筛选出影响汤圆综合品质的关键性指标,结合聚类分析得到适宜加工汤圆的原料糯米关键性指标的范围。结果表明:糯米的水分含量、脂肪含量、峰值黏度、崩解值、回生值、最低黏度、最终黏度、热焓与汤圆的质构品质存在显著(P0.05)相关性。影响汤圆综合品质的关键性指标为糯米原料的直链淀粉含量和脂肪含量,适宜加工速冻汤圆的原料糯米的直链淀粉含量应大于2.52%,脂肪含量应小于1.03%。     

芭蕉芋淀粉对米粉理化性质及粉丝品质的影响

将芭蕉芋淀粉和籼米粉按照一定比例复配并制作粉丝,以复配粉的溶胀性质、热特性、糊化特性、流变学特性为理化性质测定指标,以粉丝的质构特性、蒸煮性质、感官品质为其质量评价指标,考察了芭蕉芋淀粉对米粉理化性质和粉丝品质的影响。结果表明：随着芭蕉芋淀粉添加量的增加,复配粉的直链淀粉含量、膨润力、峰值黏度、最低黏度、降落值、糊化焓、回生焓、回生度、弹性模量、黏性模量增加,而溶解度、最终黏度、回升值、糊化温度逐渐降低;米粉丝的硬度、弹性、黏附性、咀嚼性随芭蕉芋淀粉添加量的增加而增大。与纯籼米粉粉丝相比,复配粉米粉丝的筋道感和柔韧度增强,其光滑度却下降。综合考虑,添加2%～5%芭蕉芋淀粉的米粉丝品质最佳,具有很好的可接受性。     

糜子品种理化特性与体外抗氧化性研究

对39个粳性、糯性糜子品种的品质特性进行分析。结果表明,不同糜子品种的红绿值a*、粗脂肪、灰分、直链淀粉、溶解度、膨胀度、DPPH·清除率和糊化特性差异较大。糜子的平均淀粉含量73.91%,蛋白11.37%,粗脂肪4.02%,灰分0.55%,直链淀粉11.81%,支链淀粉62.10%;糜子的多酚、黄酮含量分别为8.20 mg/g、59.00 mg/100 g,对DPPH·和ABTS+·有一定的清除作用。糯性糜子较粳性糜子色泽鲜黄,具有较高的吸水性、溶解度和膨胀度。除破损值外,粳性糜子的各糊化指标值高于糯性糜子。聚类分析将糜子品种分为4类,可满足不同的加工需求。     

Evaluation of Texture Differences among Varieties of Cooked Quinoa

Texture differences of cooked quinoa were studied among 13 different varieties. Correlations between the texture parameters and seed composition, seed characteristics, cooking quality, flour pasting properties, and flour thermal properties were determined. The results showed that texture of cooked quinoa was significantly differed among varieties. ‘Black,’ ‘Cahuil,’ and ‘Red Commercial’ yielded harder texture, while ‘49ALC,’ ‘1ESP,’ and ‘Col.#6197’ showed softer texture. ‘49ALC,’ ‘1ESP,’ ‘Col.#6197,’ and ‘QQ63’ were more adhesive, while other varieties were not sticky. The texture profile correlated to physical?‐chemical properties in different ways. Protein content was positively correlated with all the texture profile analysis (TPA) parameters. Seed hardness was positively correlated with TPA hardness, gumminess, and chewiness at P ≤ 0.09. Seed density was negatively correlated with TPA hardness, cohesiveness, gumminess, and chewiness, whereas seed coat proportion was positively correlated with these TPA parameters. Increased cooking time of quinoa was correlated with increased hardness, cohesiveness, gumminess, and chewiness. The water uptake ratio was inversely related to TPA hardness, gumminess, and chewiness. Rapid Visco Analyzer peak viscosity was negatively correlated with the hardness, gumminess, and chewiness (P < 0.07); breakdown was also negatively correlated with those TPA parameters (P < 0.09); final viscosity and setback were negatively correlated with the hardness, cohesiveness, gumminess, and chewiness (P < 0.05); setback was correlated with the adhesiveness as well (r = ?0.63, P = 0.02). Onset gelatinization temperature (T_o) was significantly positively correlated with all the texture profile parameters, and peak temperature (T_p) was moderately correlated with cohesiveness, whereas neither conclusion temperature (T_c) nor enthalpy correlated with the texture of cooked quinoa.     

糜子直链淀粉、蛋白质含量对其外观品质及食味品质的影响

以4个直链淀粉、蛋白质含量存在显著差异的糜子品种为实验材料,研究直链淀粉、蛋白质含量对糜子外观及食味品质的影响。结果表明：与低直链淀粉品种比较,高直链淀粉糜子品种,全粉糊化黏度、糊化时间、糊化温度较高,糜子饭吸水率、体积膨胀率、硬度较高,而糊化热焓值较低;蛋白质含量较高的糜子品种,全粉呈现低糊化黏度,糜子饭呈现低吸水率、体积膨胀率,高硬度。直链淀粉、蛋白质含量较高的糜子品种,蒸煮性差、能耗高、蒸煮时间长。因此,在糜子品质育种中,适当降低直链淀粉和蛋白质含量可以改善糜子的适口性。     

Effects of hydrothermal treatment on the physicochemical properties of pregelatinized rice flour

Effects of hydrothermal treatment on the pasting, thermal and hydration properties of rice flour prepared from three Indica varieties of milled rice [Taichung Sen Glutinous (TCSW) 1, Taichung Sen (TCS) 10, and TCS 17], which contained 1.2, 17.9 and 28.8% amylose, were studied. Three hydrothermally-treated factors, soaking time, steaming temperature and steaming time were investigated. From the statistical results of an experimental design of L₂₇ orthogonal array, the soaking time is a significant factor that affects the pasting properties of three varieties of rice with various degrees of influence. However, the increase of pasting temperature, reduction of peak viscosity and elevation of final viscosity were investigated for all treated non-waxy rice and resulted in the reduction of its breakdown and total setback. The differences of pasting and hydration properties of treated rice flour were attributed to the changes of rigidity of starch granules under treatment. The results of DSC showed that the degree of gelatinization was higher in waxy rice than in non-waxy rice when subjected to the same hydrothermal conditions.     

早籼稻的品质分析与其压榨型鲜湿米粉加工适应性

为确定压榨型鲜湿米粉用早籼稻的品质范围,保证米粉品质稳定性,本实验以我国早籼稻湖北省和江西省两个主产区生产的40 种早籼稻谷品种为原料,以压榨型鲜湿米粉为最终产品,采用描述性分析及相关性分析对早籼稻理化特性、糊化特性以及米粉的品质特性进行分析。结果表明：测定的15 项早籼稻品质指标中,大部分品质指标的变异系数大于10%,垩白度变异系数最高,达75.9%。相关性分析表明稻谷粒长、垩白粒率、峰值时间与米粉感官评分均呈显著相关性,直链淀粉质量分数、最低黏度、最终黏度、衰减值、回生值与米粉感官评分均呈极显著相关性;回生值与感官评分相关系数最大,达0.579;相对于理化指标,糊化特征参数能更客观反映出米粉的食用品质。基于因子分析法对早籼稻品质指标进行分析处理,结果表明总方差76.264%的贡献率来自前4 个公因子,其中2 个公因子得分与米粉感官评分呈显著相关性,相关系数分别为0.539、－0.332。以逐步回归分析法对这2 个公因子代表的指标进行分析,得出方程：Y米粉感官评分＝51.876＋0.494x直链淀粉质量分数＋0.008x回生值（R2＝0.423）,筛选出直链淀粉质量分数和回生值是影响米粉品质的敏感性指标;基于聚类分析得到适宜加工压榨型鲜湿米粉的早籼稻敏感品质指标阈值区间为直链淀粉质量分数22.24%～26.86%、回生值1 526.5～2 036.7 cP。     

Structural and Physical Properties of Starches Isolated from Six Varieties of Millet Grown in China

This study investigated the structural and physical properties of starches extracted from six varieties of millet mainly grown in China. The amylose content of millet starches ranged from 17.6 to 28.4 g/100 g (dry weight basis, db), and a variety of waxy proso millet starch (0.38 g/100 g, db) was identified. These starches exhibited a majority of large polygonal granules with several indentations, few small spherical granules, and A-type crystallinity. Proso millet starch showed prominent paste clarity and freeze-thaw stability, whereas finger millet starch exhibited the highest solubility. Moreover, barnyard millet starch had the lowest sediment volume. The gelatinization enthalpy of proso millet starch was the highest (5.16 J/g). For non-waxy millet starch, the ratio of retrogradation (R%) was positively correlated with amylose content. Among all starches, the storage modulus (G′) was higher than the loss modulus (G″) during heating and cooling. The G′ and G″ of proso millet starch and barnyard millet starch pastes were significantly lower than other starches during cooling. The pasting properties of six millet starches significantly differed, had positive correlation with amylose content, and were affected by NaCl, sucrose, and pH values.     

蛋白组分对籼米粉糊化特性的影响机理探讨

通过逐一去除蛋白组分的方法研究了蛋白组分对籼米粉糊化特性的影响,并分析了影响这些变化的蛋白结构基础。RVA和DSC分析结果表明,不同组分的蛋白在去除之后,峰值粘度、热糊粘度和最终粘度均有不同程度的升高,崩解值、回生值及糊化温度均有不同程度的降低。SDS-PAGE和显微结构分析表明,各组分对糊化特性的影响机理应有差异:谷蛋白通过与纤维素类物质的紧密结合,在糊化过程中阻碍淀粉粒的溶胀;醇溶蛋白可能是通过蛋白体自身的溶胀与淀粉相互作用而影响;清、球蛋白通过活性蛋白对籼米成分的水解或合成等改变而影响;淀粉粒结合蛋白则可能对籼米的基础糊化特性影响较大。与分离重组法比较,逐一去除蛋白组分的方法因为蛋白组分之间的相互作用影响较大,对糊化特性的影响与分离重组法略有差异。     

小米粉含量对小米小麦混合粉及其挂面品质特性的影响研究

将小米粉按照10%~80%的比例添加到小麦粉中,对小米小麦混合粉的粉质特性和糊化特性进行了分析,同时对由混合粉制作成的挂面的品质特性进行了分析研究。结果表明:1)随着小米粉添加量的增加,小米小麦混合粉的峰值黏度、最低黏度、最终黏度、回生值、衰减值和峰值时间都在降低,形成时间、稳定时间、粉质指数都是先降低再升高。2)挂面蒸煮损失率不断升高,干物质吸水率不断下降。小米添加量≤30%时,挂面品质比较好,添加量≤60%时,品质尚可,添加量60%时,挂面品质下降比较大。3)小米粉的添加量、小米小麦混合粉的RVA特性、粉质特性与混合粉挂面的蒸煮品质特性有非常高的相关性。