交联淀粉在食品加工中的应用

综述了交联淀粉的性质及其在食品加工、微胶囊膜材等方面的应用。     

变性淀粉在速冻食品中的应用

随着人们生活节奏的加决,生活水平的提高和饮食结构的变化,人们对食品的需求有了明显的变化。减轻家务劳动,日常食用些既美味又营养的食品。在讲究高效的今天,已成为普遍现象。进入90年代速冻食品的消费出现了新的热点,一些传统的食品的行列,如:速冻汤圆、速冻包子、速冻春卷等备受青眯。速冻食品一般需要经过预冷、冷冻、冷藏和使用     

交联淀粉在食品加工中的应用

综述了交联淀粉的性质及其在食品加工、微胶囊膜材等方面的应用。     

真空油炸技术及其在淀粉基食品中的应用

油炸是一种常用的食品加工方式,油炸食品因其独特的色香味受到消费者喜爱。淀粉基食品是油炸食品常用原料,薯条、油条、方便面等淀粉基油炸食品均为餐桌上的常见美食。但油炸过程可能会产生丙烯酰胺等危害物质,过量食用油炸食品会导致超重、肥胖和其他慢性疾病,对人们的身体健康不利。因此,人们开发了新型油炸技术来提高油炸食品品质,真空油炸就是其中较为成熟的一种。作者重点介绍了真空油炸技术的原理、优点及与其他技术的联用,详细阐述了真空油炸技术对淀粉特性的影响及其在淀粉基食品中的应用,以期为真空油炸淀粉基食品的研发提供参考,生产出更健康的淀粉基油炸食品,减少饮食相关慢性疾病的发生。     

蜡质马铃薯淀粉的理化特性及其在食品领域中的应用

蜡质马铃薯淀粉是一种全新的商业化淀粉，本文首次对该淀粉的理化性质进行了研究。结果表明蜡质马铃薯淀粉的直链淀粉的含量极低（0．96％），低于蜡质玉米淀粉的直链淀粉的含量（3．79％）；蛋白质及脂肪含量也低于普通马铃薯淀粉的蛋白质及脂肪含量。蜡质马铃薯淀粉的x射线衍射图谱属B型，其淀粉颗粒的大小和型态与普通马铃薯的淀粉无明显差异，但其小颗粒淀粉的比例较普通马铃薯的淀粉高。蜡质马铃薯淀粉的胀润度及淀粉糊的透明度均高于普通马铃薯的淀粉，远远高于木薯淀粉及蜡质玉米淀粉。虽然蜡质马铃薯淀粉的成糊温度与普通马铃薯淀粉及木薯淀粉的无明显差异，在水溶液中其淀粉糊的最高黏度也低于普通马铃薯淀粉，但在酸性及盐环境中蜡质马铃薯淀粉的最高黏度却大大高于普通马铃薯淀粉。由于其特殊的功能性质，可为食品领域内诸多产品的生产、开发提供新的选择，由于其高支链的特性，耐酸性、耐盐性能好、较低的糊化温度及高度的透明度，可生产出透明度极高、冻融稳定性好的高质量汤料、酱料及果酱类产品。由于其增稠稳定性能好，可替代烘焙奶油中胶体成分，带来成本的节约的可能性。由于其可提供高膨胀性能的特性，可为休闲膨化食品带来松脆的口感、光滑的外观、高度膨化的效果。     

酶制剂在蛋白食品加工中的应用／酶制剂在谷物食品中的应用

酶制剂在蛋白食品加工中的应用；酶制剂在谷物食品中的应用[编者按]     

糙米复配粉中淀粉直/支比对挤压速食粥品质与结构的影响

糙米是一种营养丰富的全谷物食品,但较差的适口性、蒸煮性和消化性制约着其成为主流餐桌食品。为改善其食用品质,本文通过分析不同淀粉直/支比(0.176、0.196、0.216、0.236、0.256、0.276)糙米复配粉的原料特性以及其对挤压速食粥糊化特性、复水品质、质构特性与结构的影响,探究制作糙米挤压速食粥原料复配粉最优的淀粉直/支比。结果表明:随着淀粉直/支比的增加,糙米复配粉的糊化温度和峰值温度增加,挤压速食粥米粒横截面的光滑度及紧密度增加。当淀粉直/支比为0.256时,挤压速食粥米粒横截面的结构最均一、最紧密,复水时间达到12.6 min,米汤固形物损失率和径向膨胀率最小(0.153 g和2.282%),此时的硬度、胶着度和耐咀性明显高于淀粉直/支比0.276,达到3323.85 g、1242.76 g·s和744.73 g。可见,糙米复配粉中淀粉直/支比0.256为制作挤压速食粥的较佳比例。     

淀粉玻璃化转变及其对食品品质影响

淀粉是以谷物为原料的食品主要成分,而淀粉玻璃化转变对食品品质,特别对质构具有显著影响。该文在有关玻璃态和玻璃化转变理论基础上,综述淀粉玻璃化转变分析方法、影响因素及其对食品品质影响,并对今后研究方向进行展望。     

甘薯块根膨大过程中质构特性和淀粉直/支比的研究

甘薯块根膨大过程中质构特性和淀粉组分的变化对甘薯的品质和用途有着重要影响。本研究选取3种甘薯类型和4个时期,通过质地多面分析法(TPA)和双波长碘比色法,分析其质构特性和淀粉直链淀粉和支链淀粉比值(淀粉直/支比)随块根膨大的变化规律。结果表明,甘薯淀粉直/支比在扦插后80天开始下降,至扦插后110天达到谷值,之后小幅回升;整体上,甘薯扦插后的天数与淀粉直/支比、内聚性和弹性呈显著负相关(r =-0.390, r= -0.367, P <0.05;r= -0.634, P <0.01);与硬度呈显著正相关(r= 0.590, P <0.01)。淀粉直/支比与块根的内聚性、弹性和咀嚼性呈显著正相关(r =0.368, P <0.05; r= 0.463, r= 0.642, P <0.01);综合分析发现,扦插后80~110天（块根膨大高峰期至膨大后期）收获的甘薯适合水果型(生食型)甘薯的开发。     

淀粉直/支比对高酯果胶凝胶性质的影响

采用流变仪和质构仪考察淀粉的直/支比对高酯果胶凝胶性质的影响。动态流变学测试结果表明：随着直链淀粉比例的增加,凝胶体系的储能模量和损耗模量值升高,损耗因子降低,体系表现出更为优越的黏弹性。静态流变测试结果表明：随着直链淀粉比例的增加,凝胶体系的稠度系数K值增加,流体指数n降低,触变环面积增大,形成的三维网络凝胶结构致密。质构测试结果表明：随着直链淀粉比例的增加,凝胶体系的硬度、内聚性和黏着性均显著增加。相互作用力的测定结果表明：淀粉与果胶之间通过氢键发生相互作用。     

优化毛细管电泳法测定山药淀粉中直链/支链淀粉

以市售新鲜怀山药为原料通过石灰水浸泡法制备山药粉,并通过正丁醇反复结晶法分离纯化直链淀粉与支链淀粉。利用碘做显色剂,使用毛细管电泳法测定山药淀粉中直链淀粉与支链淀粉的含量以及比率,本文分别对柠檬酸-磷酸盐缓冲液以及醋酸-醋酸盐缓冲液等不同缓冲液作为流动相进行了对比,实验发现醋酸-醋酸盐缓冲液对于分离测定直链淀粉与支链淀粉的效果较好。随后分析了不同p H条件下的醋酸-醋酸盐缓冲液进行的分离效果进行了比较,并测定其迁移率,当p H 4.8时分离效果最佳且其迁移率达到15.4。利用最佳条件使用纯的马铃薯直链淀粉与支链淀粉标准品,得出支链淀粉的保留时间约为1.8 min,而直链淀粉的保留时间约为2.9 min,对怀山药淀粉进行分析,从而得出怀山药中直链淀粉含量为19.49%。利用重复性试验以及回收率试验该方法的准确性与精确度能达到很好的效果。     

Reactivity of Amylose and Amylopectin in Potato Starch

The availability for reaction of amylose and amylopectin in potato starch was investigated by etherifying potato starch in granular form and in solution with diethylaminoethylchloride to a very low degree of substitution. The distribution of ether groups over both starch fractions was subsequently determined. A higher reactivity of amylose with respect to amylopectin was found for granular starch, in contrast with reaction in solution, where both starch fractions show almost equal degree of substitution. This indicates a difference in physical state between amylose and amylopectin in granular potato starch. Furthermore it was shown, that the relative reactivity of the starch fractions can be varied by physical modification of the native starch.     

直链淀粉和支链淀粉的表征

直链淀粉和支链淀粉是淀粉的两大主要组分,它们在分子结构以及分子聚集态等方面的差异导致其物化特性有所不同,具有不同直链和支链淀粉组成比例的淀粉在总体应用表现也不相同。本文通过讨论淀粉最新的研究进展,对直链淀粉和支链淀粉的纯度、分子结构、相对分子质量、晶体特性、热焓特性、黏度特性等进行综述。     

The Influence of Environment on Starch Content and Amylose to Amylopectin Ratio in Wheat

There is evidence that starch content plays an active role in determining dough rheological characteristics. The aim of this study was to determine the influence of environment on starch content and amylose: amylopectin ratio, and how this affects breadmaking quality. Ten hard red spring wheat cultivars were planted in three different environments in a randomized complete block design with three replications. Total starch content, amylose: amylopectin ratio, milling, rheological and baking characteristics were measured. Starch content was significantly influenced by the environment. It was significantly negatively correlated with loaf volume, wet gluten content and flour protein content across the three environments. Starch content and protein content were significantly negatively correlated, yet the value was relatively small (r = −0.4) and the relationship was therefore not directly inverse, and other factors influenced this relationship. Some cultivars interacted with specific environments, and they ranked high for starch content and loaf volume. Amylose: amylopectin ratio was very consistent for the three environments but was not significantly correlated with breadmaking quality characteristics across the environments, although there were significant correlations at individual environments. Cultivar choice and environment where cultivars are planted will therefore affect the starch content. High starch content will not necessarily lead to poor baking quality.     

Measurement of Amylose/Amylopectin Ratio by High-Performance Liquid Chromatography

Amylose content has been measured by iso-amylase digestion of starch followed by quantitation of the amounts of the higher molecular weight chains (from amylose) and the lower molecular weight chains (from amylopectin). The separatrion and quantitation has been performed by size-exclusion high performance liquid chromatography on hydrophilic columns. Three columns were tested and an Ultrahydrogel 250 was found to provide the optimum separation. Starches of up to 30-35 per cent amylose may be analysed in this way without the need for first removing the lipids. With starch of higher amylose content, precipitation of the amylose in the sample may occur while it is awaiting HPLC analysis. This precipitation can be prevented in starches of up to 40 per cent amylose by the use of dimethyl sulfoxide in the reaction mixture. Samples with amylose content higher than this always show some precipitation and the amylose contents obtained are similar for all starches with amylose in the range from 40 to 80 per cent, measured by iodine determination. The method gives results which are more repeatable than those obtained by spectrophotometric determination of iodine binding, and which appear to be unaffected by the lipid content of the starch.     

黑豆蛋白对不同直/支比玉米淀粉凝胶及其结构的影响

探究黑豆分离蛋白对不同直/支比玉米淀粉凝胶特性及微观结构的影响。以来源于玉米的普通淀粉（CS）和高支淀粉（HAS）为原料,探讨添加黑豆分离蛋白（BBPI）对共混体系【10 ∶ 0,9.5 ∶ 0.5,9.0 ∶ 1.0,8.5 ∶ 1.5,8.0 ∶ 2.0,CS（HAS）/BBPI的质量比】糊化特性、动态流变特性、静态流变特性、质构特性及微观结构的影响。结果表明：添加BBPI对CS（HAS）/BBPI体系凝胶及结构性质影响显著,且对CS体系影响程度更大。随着BBPI添加比例的增大,CS/BBPI、HAS/BBPI体系峰值黏度、回生值逐渐降低,糊化时间延迟;体系贮能模量、损耗模量逐渐降低,tanδ先升高后降低,凝胶强度变弱,体系剪切应力不同程度降低;体系凝胶硬度、内聚性逐渐降低。微观形貌表征发现,添加BBPI使CS（HAS）/BBPI凝胶网络结构致密性变差,轮廓模糊,孔洞变大,孔壁变薄,且出现碎片集结。在淀粉基食品加工过程中,适量添加BBPI可降低产品回生程度,提升产品营养及食用品质。     

Starch Biosynthesis. I. The Size Distributions of Amylose and Amylopectin and Their Relationships to the Biosynthesis of Starch

Equations for the size distributions of both linear and branched polymers were applied to debranched amylopectin, linear amylose, and branched amylose polymers. The experimental size distribution of linear amylose corresponds to the broad size distribution of an A–B condensation polymer, whereas that of debranched amylopectin linear chains corresponds to the much narrower Poisson size distribution. These dramatic differences illustrate that different types of enzymes synthesize the linear chains of amylose as compared to those of amylopectin. These results support the previously proposed mechanism. The polymodal behavior of debranched amylopectin is due to the existance of individual Poisson-type polymers created by tier structures in a statistically formed precursor glycogen. Equations were developed which enable the calculation of the percentages of these individual Poisson polymers. When applied to the differences between shx and Bomi barley amylopectins, it is concluded that both studies agree that two different short, inner tier, A-chains exist, where the longer chain is located in the more external third tier in the amylopectins. In amylose, three different polymers exist: A linear amylose A–B type condensation polymer, a branched amylose which behaves as a statistical A–R–B₂ type polymer, and an intermediate, non-statistically branched amylose polymer.     

双波长比色法测定马铃薯直链/支链淀粉含量

将新鲜马铃薯中的淀粉提出后,采用双波长比色法测定了直链/支链淀粉含量。淀粉经I2-KI溶液染色,直链淀粉呈蓝色,支链淀粉呈紫色。535和570 nm用于直链淀粉含量测定,555和760 nm用于支链淀粉含量测定。结果表明,样品溶解是检测的关键,淀粉与碘试剂的反应时间会对测定结果造成一定影响。同时通过本方法的检测,新大坪品种马铃薯的直链淀粉含量为21.20%,支链淀粉含量为78.80%。     

Localisation of Amylose and Amylopectin in Starch Granules Using Enzyme-Gold Labelling

The independent localisation of amylose and amylopectin in a range of dry and hydrated native starch granules with varying amylose content (0—70 %) has been indirectly visualised using enzyme-gold cytochemical markers. Increasing amylose content was clearly demonstrated to result in distinct changes in granule architecture. In the absence of amylose (waxy maize starch) a framework of closely packed concentric layers of amylopectin exists in the granules. Low amylose content (potato starch) results in alternating layers of densely packed amylopectin and amylose molecules. High amylose content (amylomaize starch) granules were shown to possess an amylopectin centre surrounded by an amylose periphery encapsulated by an amylopectin surface. Elongated granules without the amylopectin centre were also observed in high amylose starches suggesting a relationship between amylopectin, amylose and granule shape. A model of starch granule architecture is proposed where increased compartmentalisation of amylose and amylopectin is observed in granules containing increasing levels of amylose.