肉制品辅料对木薯淀粉糊化黏度的影响

木薯淀粉可作为肉制品中的黏结剂，对改善肉制品的组织结构有重要作用。通过对木薯淀粉糊化黏度的测定，以及脂肪、食盐、葡萄糖、大豆分离蛋白等肉制品中主要营养成分对木薯淀粉糊化黏度的影响研究，为木薯淀粉在肉制品中的应用提供理论基础。     

淀粉磷酸酯基本特性及糊化黏度影响因素的研究

淀粉磷酸酯具有较强的冻融稳定性、抗凝沉性,较高的膨胀度、透明度,是肉制品生产中常用的黏结剂,对改善肉制品的组织结构有重要作用。通过对淀粉磷酸酯的透光率、冻融稳定性、膨胀度、凝沉性和糊化黏度的测定,以及脂肪、食盐、葡萄糖、大豆分离蛋白等肉制品辅料成分对淀粉磷酸酯的糊化黏度影响的研究,为淀粉磷酸酯在肉制品中的应用提供理论基础。     

海藻酸钠对不同直链淀粉含量的玉米淀粉物化性质的影响

采用快速黏度分析仪、差示扫描量热仪、动态流变仪、物性测试仪等,研究了海藻酸钠对3种不同直链淀粉含量的玉米淀粉糊化、凝胶及老化性质的影响。结果表明:海藻酸钠显著影响高直链玉米淀粉、普通玉米淀粉及蜡质玉米淀粉的物化性质,且对不同直链淀粉含量的玉米淀粉物化性质的影响不同。海藻酸钠使3种玉米淀粉的糊化难度增大,起始糊化温度、峰值糊化温度、终止糊化温度升高,糊化焓增加。海藻酸钠提高3种玉米淀粉的峰值黏度、末值黏度、表观黏度及损耗模量。海藻酸钠提高高直链玉米淀粉的热稳定性和抗老化性,使高直链玉米淀粉的衰减值、老化率降低。海藻酸钠阻碍高直链玉米淀粉形成凝胶,使高直链玉米淀粉的损耗角正切值升高、凝胶硬度降低。     

黄原胶对玉米淀粉糊化性能的影响

将黄原胶引入到淀粉浆料中,采用快速黏度分析法(RVA)研究了黄原胶的加入对玉米淀粉糊化性能和浆液表观黏度的影响,讨论了黄原胶与玉米淀粉分子之间的相互作用.结果表明:黄原胶可促进淀粉糊化,降低淀粉的糊化温度,缩短糊化时间;随着黄原胶质量分数的增加,淀粉的糊化峰值黏度增加,表现了2种高分子的相互作用;黏度衰减值随黄原胶增加...     

共轭亚油酸对玉米淀粉理化性质的影响

采用快速黏度分析仪、差示扫描量热仪和动态流变仪研究了共轭亚油酸对3种不同直链淀粉含量的玉米淀粉糊化性质、热学性质和流变学性质的影响。研究表明,添加相同量的共轭亚油酸使普通玉米淀粉的峰值黏度等黏度值增加,对高直链玉米淀粉和蜡质玉米淀粉的糊化性质影响不显著。添加共轭亚油酸使普通玉米淀粉糊化焓值增加,添加量为1%时其糊化焓值增加幅度最大。添加2%的共轭亚油酸使高直链玉米淀粉和蜡质玉米淀粉糊化焓值降低,其中蜡质玉米淀粉糊化焓值降低尤为明显,下降了17%。添加2%的共轭亚油酸,可抑制高直链玉米淀粉的短期老化和长期老化,老化率分别由0.45、0.63降低到0.31、0.55。添加共轭亚油酸增加3种玉米淀粉的表观黏度和稠度系数,增加普通玉米淀粉和高直链玉米淀粉的贮能模量和损耗模量,降低其tanδ值,促进其形成弹性凝胶。     

配料对淀粉峰值黏度和糊化温度的影响

采用RVA快速黏度仪研究了食盐、蔗糖和植脂末等配料对普通和高支链玉米淀粉的峰值粘度和糊化温度的影响。结果表明,对于NaCl和蔗糖来说,随着其质量分数的升高,普通和高支链淀粉的峰值黏度和糊化温度均增大;而对于植脂末,普通淀粉在其质量分数小于6%时,其峰值黏度升高,糊化温度基本不变,大于6%时,峰值黏度和糊化温度均降低。高支链玉米淀粉在植脂末质量分数小于4%时峰值黏度和糊化温度均略微降低,而大于4%时均升高。研究结果有助于阐明玉米淀粉糊化的规律,以及为其它谷物淀粉糊化工艺提供借鉴。     

脂肪酸的链长和不饱和度对脂肪酸-普通玉米淀粉复合物理化性质的影响

为探讨脂肪酸对玉米淀粉性质的影响,采用快速黏度分析仪、差示扫描量热仪及动态流变仪研究了6种不同链长和不饱和程度的脂肪酸对普通玉米淀粉糊化性质、热学性质及流变学性质的影响。研究结果表明,添加6种脂肪酸对普通玉米淀粉的糊化温度无明显影响,可使普通玉米淀粉的峰值黏度约下降8.22%~14.71%。除棕榈酸外,其余脂肪酸均能使普通玉米淀粉的糊化焓值降低,脂肪酸碳链越短,不饱和度越低,普通玉米淀粉的糊化焓值越低。共轭亚油酸-普通玉米淀粉复合物的抗老化效果最好,添加共轭亚油酸使原淀粉长期老化率约下降28.36%。随着脂肪酸不饱和度的增加,普通玉米淀粉的表观黏度逐渐增加。添加6种脂肪酸使普通玉米淀粉的tanδ降低,有利于其弹性凝胶的形成。     

反应程序和淀粉浓度对糯玉米和普通玉米淀粉快速黏度测定谱特征值的影响

以糯玉米品种渝糯7号和普通玉米品种农大108为材料,研究了不同的反应程序和淀粉浓度对其快速黏度测定(RVA)谱特征值的影响,同时比较了糯玉米和普通玉米淀粉在不同反应程序和淀粉浓度条件下的差异。结果表明:(1)玉米淀粉的RVA特征值在不同反应程序下发生了改变,但其没有改变糯玉米和普通玉米之间的差异,在不同反应程序下,相对于普通玉米淀粉,糯玉米淀粉的峰值黏度和沉降值较高,而谷值黏度、终值黏度、回复值、峰值时间和糊化温度较低。(2)糯玉米和普通玉米淀粉的RVA特征值受到浓度影响,随着淀粉浓度的增加,峰值黏度、谷值黏度、沉降值、终值黏度和回复值随之增加,峰值时间略有降低,浓度太低时淀粉不能糊化,在能糊化条件下则随着浓度的增加而降低。在低浓度条件下,糯玉米淀粉的峰值黏度高于普通玉米,而在较高浓度(11%)条件下,糯玉米淀粉的峰值黏度则低于普通玉米淀粉。     

阿拉伯胶对玉米淀粉的共混改性

用阿拉伯胶对玉米淀粉浆料共混改性,使用快速黏度仪(RVA)测定阿拉伯胶-玉米淀粉体系的糊化性能,分析阿拉伯胶对淀粉成膜性能的影响。结果表明,阿拉伯胶会大大降低淀粉糊化的峰值黏度和衰减值,提高淀粉浆膜的断裂强度和断裂伸长,并改善淀粉浆膜的硬脆性。     

不同类型玉米发育过程中淀粉糊化特性的比较

采用DGC方差分析法,比较普通玉米、糯玉米和爆裂玉米籽粒生长过程中胚乳淀粉糊化特性和直链淀粉含量的变化及差异。结果表明,普通玉米和爆裂玉米RVA谱的尾部高于峰顶,而糯玉米RVA谱的尾部低于峰顶。普通玉米的低谷黏度授粉后10 d达最高,峰值黏度和最终黏度分别在20 d和30 d时最高;糯玉米的峰值黏度、低谷黏度和最终黏度均在30 d时最高,爆裂玉米均在40 d时最高。说明,普通玉米胚乳的淀粉膨胀力、耐剪切能力和淀粉胶的硬度最先达到最大,其次为糯玉米,爆裂玉米最晚。糯玉米胚乳中直链淀粉含量最低,回复值最低,最不易老化。授粉20 d后,爆裂玉米淀粉的峰值时间最长,糊化温度最高,最难糊化。相关分析发现,糯玉米的直链淀粉含量与回复值和糊化温度分别呈显著正和负相关,爆裂玉米直链淀粉含量与消减值呈显著正相关,而普通玉米直链淀粉含量与RVA特征值间不存在显著相关性,即相关性的大小受玉米类型的影响。     

Gelatinization of Thermally Treated Starch Mixed with Sodium Hydroxide in the Solid State

The effect of thermal treatment on maize starch mixed with different amounts of sodium hydroxide, in the solid state, on its gelatinization was thoroughly investigated. Besides, the rheological properties of the products which undergo gelatinization by addition of water at room temperature after treatment were also investigated. It was found that gelatinization of thermally treated starch with sodium hydroxide in the solid state starts only at a ratio of alkali: starch of 1:10 or more regardless of the temperature of treatment. The rheological properties as well as the apparent viscosity at various rates of shear were found to be dependent on both the temperature of treatment an the sodium hydroxide: starch ratio. Storing of the thermally treated gelatinized starch pastes for 7 days is accompanied by a remarkable increase in their apparent viscosity at any specific rate of shear which may be due to the effect of sodium hydroxide on starch during storing.     

Endosperm Structure and Physicochemical Properties of Starches from Normal,Waxy, and Super-Sweet Maize

Maize is a main botanical source used for extraction of starch in the world market. New maize cultivars with different amylose contents and special starch metabolism characteristics have been generated. Three types of maize cultivars, namely, normal maize, waxy maize (wxwx homozygous mutant), and super-sweet maize (sh2sh2 homozygous mutant), were investigated to determine differences in endosperm structures, morphologies, and physicochemical properties of starches. Maize kernels exhibited significantly different contents of total starch, soluble sugar, and amylose. Normal maize kernels contained the largest proportion of floury endosperm, followed by waxy maize and then super-sweet maize. Normal maize starch and waxy maize starch were larger in size than super-sweet maize starch. Normal maize starch and waxy maize starch were spherical and polygonal in floury and vitreous endosperms, respectively. Super-sweet maize starch was spherical both in floury and vitreous endosperms. Waxy maize starch showed the strongest birefringence patterns, the highest crystallinity and the largest proportion of ordered structure in external region of granules, and the largest proportion of double helix components, followed by normal maize starch and then super-sweet maize starch. Waxy maize starch showed the highest peak viscosity, trough viscosity, breakdown viscosity, gelatinization temperatures (i.e., gelatinization conclusion temperature, gelatinization onset temperature, gelatinization peak temperature, and gelatinization enthalpy). By contrast, super-sweet maize starch showed the lowest corresponding values for these parameters.     

蛀蚀害虫侵害后小麦粗淀粉含量及其糊化特性变化

为探讨蛀食性害虫玉米象、米象侵害后小麦粗淀粉含量和全麦粉糊化特性的变化,选用河南产储藏3年的商品小麦为材料,按不同虫种分组,设定不同的虫口密度和侵害时间,检测害虫感染后小麦粗淀粉含量和全麦粉的糊化特性。结果表明:玉米象和米象不同程度感染后小麦粗淀粉含量总体呈下降趋势;无论是同一虫口密度随着蛀蚀时间的延长,还是同一蛀蚀时间下随虫口密度增加,其感染后的全麦粉峰值黏度、最低黏度、最终黏度、衰减值和回生值均呈下降趋势;糊化温度呈上升趋势,峰值时间基本无变化;粗淀粉含量与峰值黏度、最低黏度、最终黏度、衰减值和回生值均存在极显著正相关,与糊化温度呈极显著负相关,与峰值时间无相关性。     

小米淀粉与玉米淀粉糊性质比较研究

对小米淀粉和玉米淀粉糊性质进行较详细比较研究,包括透明度、冻融稳定性、凝沉性、膨胀力、酸解、酶解,和介质对糊粘度性质影响。结果表明,小米淀粉与玉米淀粉相比,糊的凝胶稳定性好、持水力强、膨胀力高、糊化温度高、热焓变值大、但透明度较差、冻融稳定性不佳、热稳定性差;且氯化钠及糖溶液对小米淀粉糊粘度性质影响较大。     

韧化处理对不同玉米淀粉理化特性的影响

以不同直/支链比例的普通玉米淀粉和蜡质玉米淀粉为材料,在40、50、60℃进行韧化处理,研究韧化处理对玉米淀粉理化特性的影响。结果表明：韧化处理的两种玉米淀粉颗粒形貌有较小变化。韧化处理后,两种淀粉的溶解度和膨胀度随着处理温度的升高而降低;所有韧化处理过的玉米淀粉黏度低于原淀粉,起糊温度高于原淀粉;韧化处理后淀粉的糊化温度升高,热焓变化不大。     

Gelatinization of Starch in Aqueous Alkaline Solutions

The effect of kind and concentration of alkali on the gelatinization of maize, rice and wheat starches were thoroughly investigated. No gelatinization could be observed on using the carbonate and/or bicarbonate of sodium and potassium even on using their saturated solutions, while both sodium and potassium hydroxides undergo gelatinization. Gelatinization of starch occurs immediately at a concentration of sodium hydroxide of 1.2%, while clear gelatinized pastes could be obtained at 4% or more. Infra-red spectra of maize and rice starches before and after alkali treatment reveal that treatment of starch with sodium hydroxide is accompanied by some physicochemical changes in the structure of starch. The rheological properties as well as the apparent viscosity of the gelatinized starch pastes depend on the kind of starch as well as the nature and concentration of alkali used.     

Gelatinization of Starch During Preparation of Indian Unleaved Flat Breads

The comparison of starch granule deformation and extent of starch gelatinization in a few common Indian unleavened flat breads (Chapati, Parontha and Poorie) was made. The starch granule swelling was evaluated by scanning electron as well as polarized light microscopy. The peak viscosity in Haake rotary viscosimeter and hydration capacity were used for comparing the extent of starch gelatinization in crust and crumb of these baked products. Although a few of the starch granules on the outside of crust, maintained a weak outline those in the crumb area gave only a matrix of gelatinized starch. The extent of starch gelatinization was reflected by the related increase in hydration capacity of these products. However, the peak viscosity values were found to be inversely related to the extent of starch gelatinization. As compared to crumb, a higher extent of browning was observed in the crust. Water absorption, type of cereal, mode and efficiency of heat transfer were found to control the extent of starch gelatinization in these baked products.     

高直链玉米淀粉性质的研究

以选育的高直链玉米为试材,在实验室条件下提取高直链玉米淀粉,并对其表面结构、直链淀粉含量、热焓特性、淀粉的黏度、糊化温度及淀粉糊性质等方面进行了比较系统的研究,为今后高直链玉米淀粉的应用提供理论依据。     

Physicochemical changes of maize starch during the lime-heat treatment for tortilla making

As measured by the Brabender viscoamylograph, alkali-cooking and soaking of maize in water (nixtamalization) caused large increases in viscosity, as compared with native flour. Marked effects of cooking time on the pasting properties of nixtamal were also observed. As assessed by the blue value method, nixtamalization does not cause extensive gelatinization of the starch. This was supported by differential scanning calorimetric studies, which yielded similar gelatinization endotherms for untreated maize and nixtamal flours. However, no endotherm peak appeared in tortilla samples made from this nixtamal. Furthermore, untreated maize and nixtamal flours contained many unswollen starch granules.