淀粉糊化和回生的研究

对淀粉糊化和老化现象进行了论述，着重介绍了其影响因素，并概述了淀粉糊化和老化的测定方法。     

THE EFFECT OF ANNEALING ON THE PHYSICOCHEMICAL PROPERTIES OF WHEAT, OAT, POTATO AND LENTIL STARCHES

Native wheat, oat, potato and lentil starches were annealed at various starch/water ratios at 50C for time intervals ranging from 0.5 to 72 h. Annealing did not change granule size and shape. Oat starch granules were less compactly packed after annealing. X-ray diffraction patterns remained unchanged and X-ray intensities changed only marginally in all starches. The swelling factor (SF), amylose leaching (AML) and the gelatinization temperature range (GTR) decreased on annealing. The extent of decrease in SF and AML followed the order: lentil > wheat > potato > oat, while the corresponding order for GTR was: wheat > lentil > oat > potato. The gelatinization transition temperatures (GTT) and enthalpy (ΔH) increased on annealing. However, the increases in GTT and ΔH did not begin concurrently during the time course of annealing. Increases in ΔH were slower and were evident only after 1, 2, 6 and 48 h, respectively, in lentil, potato, oat and wheat starches. The extent and rate of increase in GTT and ΔH followed the order: potato > lentil > wheat > oat. The magnitude of changes in GTT and ΔH increased with increase in annealing moisture content. The susceptibility of oat starch to enzyme and acid hydrolysis increased on annealing. However, decreases occurred in the other starches (lentil > wheat > potato). Thermal and shear stability of starch granules increased on annealing (potato > lentil > wheat > oat). The results showed that the above changes in physicochemical properties were due to increased interaction between starch components during annealing.     

VISCOELASTIC BEHAVIOUR DURING THE GELATINIZATION OF STARCH I. COMPARISON OF WHEAT, MAIZE, POTATO and WAXY-BARLEY STARCHES

Dynamic measurements were used to characterize the viscoelastic behavior during gelatinization of wheat, maize, potato and waxy-barley starches. During the experimental conditions used the curves of storage modulus (G') and loss modulus (G") versus temperature showed an initial peak for all starches, followed by a second peak at 90–95° C in the case of wheat and maize starches. Wheat starch gave a more viscous response than the other starches. The changes in G' and G" were correlated to the changes in gel volume and amylose leaching during the heating. The results were interpreted using a composite material as a model for the starch gel.     

小麦和甘薯抗性淀粉得率的工艺研究

采用酸变性和沸水浴的方法，对小麦和甘薯淀粉进行处理，以抗性淀粉得率作为评价指标，研究了在不同的淀粉乳浓度、盐酸用量、酸解时间、沸水浴时间、不同冷藏温度和时间条件下，小麦和甘薯淀粉糊化后形成抗性淀粉得率的变化情况，得到在不同条件下抗性淀粉得率受影响的趋势。     

STUDIES ON THE EFFECT OF GERMINATION TIME AND TEMPERATURE ON MALTING OF RICE

The effect of germination conditions on rice malt quality was studied by germinating rice for different periods of time up to 7 days over a range of temperatures (22° to 32°C). Germination time and temperature had a significant effect on rice malt diastatic power, cold and hot water extracts, total reducing sugars, and free alpha amino nitrogen. In general, diastatic power, cold water extract, hot water extract, total reducing sugars and free alpha amino nitrogen, all increased with germination time and temperature. Germination temperatures of 28°C and 30°C were good for the development of diastatic power, cold water extract, hot water extract, total reducing sugars and free alpha amino nitrogen. However germinating at 30°C gave maximum result. The mashing trials with rice malted for 6 days showed a slow and incomplete saccharification, slow filtration rate, and high total available extract in spent grains.     

非油炸型速冻马铃薯预处理加工工艺参数的研究

传统的速冻马铃薯产品大部分都采用了油炸工艺，而马铃薯高温油炸时会产生致癌物质丙烯酰胺，对人体有害。为了开发食用安全的速冻马铃薯新品种，采用正交试验和综合评分，对非油炸型速冻马铃薯的预处理加工工艺条件进行了研究。研究了马铃薯品种（A）、热烫温度（B）、热烫时间（C）和马铃薯直径（D）对速冻后产品的失重率、硬度、多酚氧化酶活性和过氧化氢酶活性的影响。结果表明：试验因子对其影响的主次顺序为B〉C〉A〉D；最佳方案为A4B3C2D2即以中薯3号为原料．马铃薯直径为4．5cm，110℃热烫3min。产品的品质最佳。     

紫甘薯米酒生产工艺的研究

以紫甘薯、糯米为主要原料，将二者混合进行发酵。通过一系列单因子试验和正交试验确定出紫甘薯米酒生产的较佳工艺条件为：发酵时间51h，糯米与紫甘薯的质量比为10：1，混合物料与酒曲的质量比为7：1，发酵温度为28℃。     

INFLUENCE OF FRICTION, SAMPLE DIMENSIONS AND DEFORMATION RATE ON THE UNIAXIAL COMPRESSION OF RAW POTATO FLESH

The influence of surface friction and lubrication on the compression behavior, at compression rates of 5–100mm min^−l, of cylindrical samples of potato flesh have been examined with an Instron Universal Testing Machine at room temperature. The samples had length/diameter ratios of 0.2–0.8. Parameters derived from compression to failure were: failure stress; failure strain; and apparent modulus of elasticity. Stress relaxation with time was studied using samples with length/diameter ratios of 0.4–0.8 following compressions of 10 and 30%. The length/diameter ratio, rate of compression, surface friction and lubrication influenced the parameters derived from both the compression and the stress relaxation tests. Relaxation times increased following sample lubrication. The effect due to surface lubrication was smaller than in previous compression and relaxation tests on Gouda cheese. This was attributed to release of fluid from the damaged cellular tissue of the potato flesh which reduced the effectiveness of the lubricant film.     

红薯梗、茎、叶提取物抗氧化活性研究

用DPPH法分别测定了红薯梗、茎、叶提取物的抗氧化活性，用分光光度法测定了它们的总黄酮含量，并比较了两者的相关性。实验表明：红薯梗、茎、叶提取物均具有较强的抗氧化活性，其抗氧化活性与总黄酮含量的相关系数为0．5073，相关性不显著。     

EFFECT OF SUGARS ON THE THERMAL AND RETROGRADATION PROPERTIES OF OAT STARCHES

The thermal and retrogradation properties of oat starches from two cultivars (NO 753-2 and AC Stewart) were characterized in the presence of glucose, fructose and sucrose at a concentration of 36% w/v. In both oat starches, amylose leaching (AML) and swelling factor (SF) decreased in the presence of sugars (sucrose > glucose > fructose). These decreases were more pronounced in AC Stewart starch. The decrease in AML showed that sugars interact with amylose chains within the amorphous regions of the starch granule. The gelatinization transition temperature and the enthalpy of gelatinization increased in the presence of sugars (sucrose > glucose > fructose). The above increase was also more pronounced in AC Stewart starch. The decrease in SF and the increase in gelatinization parameters indicated that these changes were influenced by the interplay of factors such as starch-sugar interaction, changes in water structure in the presence of sugars, and the antiplastizing properties of sugars relative to water. The retrogradation enthalpy and the X-ray diffraction intensities of NO 753-2 and AC Stewart starch gels (stored at 4C) increased in the presence of sugars (glucose > fructose > sucrose). These changes were more pronounced in NO 753-2 starch. The results showed that interaction (during storage) between leached amylopectin and sugar molecules was the main causative factor influencing oat starch retrogradation.     

共混对淀粉玻璃化转变特性的影响

采用DSC曲线分析法对各种添加刑与淀粉的相容性进行了判断，首次给出了这些添加剂与淀粉的相客性结果。对黄原肢与淀粉的共混体系的玻璃化转变行为进行了实验研究，根据高分子聚合物的共混模型对糯米淀粉与黄原胶共混物的玻璃化转变实验数据进行了拟合，得到适用于此体系的经验关联式，并应用玉米等其他淀粉与黄原胶共混后的实验数据进行验证，表明该关联式可用于定量预计淀粉与黄原肢共混后的玻璃化温度。     

复配型改良剂对蒸烤馒头老化影响的研究

馒头的老化是制约馒头工业化进程的一个关键问题。防止馒头老化较为有效的方法是在馒头的配方中添加各种可食用的乳化剂，使馒头中各纽分分散润湿良好。通过对复配型添加剂在馒头生产中的应用研究和对比实验，开发出在馒头中增添该复配型添加剂的生产工艺，有效地解决了目前馒头变硬、口感不佳、失水等问题。     

EFFECT OF DEFORMATION RATE AND MOISTURE CONTENT ON RICE GRAIN STIFFNESS1

Grains of brown rice, paddy variety IR-8, were subjected to two types of uniaxial compressive loading, constant displacement rate and sinusoidally varying stress, to determine behavior over a wide range of time scale. Grains from four different moisture level groups were used. With a time decrease from 120 to 1.6 × 10^?4s the relaxation modulus increased 15, 25, 16 and 20 fold at respective moisture contents of 12, 17, 22 and 27%. A master relaxation curve for each moisture content is presented. Understanding the viscoelastic behavior of brown rice as a function at time and moisture content is basic to the solution of stress-strain analysis problems.     

硒化红薯叶多糖的制备及抗氧化活性研究

以自制的红薯叶多糖为原料,利用硒化试剂SeOCl2进行硒化反应,实验结果证明硒化试剂用量和反应温度会影响产物的含硒量.反应温度为70℃、硒化试剂加入量为2mL时,硒化红薯叶多搪的收率和含硒量分别为84.5%,358 μg/g.硒化红薯叶多糖对羟自由基的清除能力明显增强,而对超氧阴离子自由基的清除能力则变化不大.     

FLOW BEHAVIOUR OF CALCIUM COMPLEXED HYDROXYPROPYL RICE STARCHES

The flow behaviour characteristics of native, hydroxypropyl starches and their calcium complexes were determined at different levels of starch concentrations, temperatures and shear rates. Hydroxypropyl starch with different Molar Substitution (MS = 0.02–0.12) were used. Both native and hydroxypropyl starch were treated with varying amount of calcium (50–250 μg/g starch). Flow properties were affected due to hydroxypropylation and their calcium treatment. The flow properties were evaluated by power law equation.     

THE FLOW PROPERTIES OF NATIVE, HEAT-MOISTURE TREATED, AND ANNEALED STARCHES FROM WHEAT, OAT, POTATO AND LENTIL

The effect of heat-moisture treatment (30% moisture, 100C, 16 h) and annealing (75 % moisture, 50C, 72 h) on the flow behavior of gelatinized starch pastes from wheat, oat, lentil and potato starches were studied at a concentration of 6% starch with a cone and plate viscometer (Wells Brookfield RVTDV II CP 200). The power law rheological model (σ=Kγⁿ) was used to describe the flow behavior of the above starch pastes. All native starches exhibited a non-Newtonian shear thinning behavior. A thixotropic loop was evident only in oat starches and native potato starch. Among native starches, the magnitude of the shear thinning index (n) followed the order: oat > wheat > lentil > potato, while the corresponding order for the consistency index (K) was: potato > lentil > wheat > oat. Heat-moisture treatment decreased the K value of all starches. On annealing, K decreased in wheat and lentil starches, but increased in potato and oat starches. Heat-moisture treatment and annealing increased the n value of wheat, lentil and potato starches, but decreased that of oat starch. In all starches, the modification to the flow behavior was more marked on heat-moisture treatment than on annealing.