A New Hydrocyclone Process for the Production of Potato Starch with Lowest Fresh Water Consumption

A drastic reduction of fresh water consumption for extraction and refining of potato starch was reached in a new process. The undiluted potato rasp is pumped directly into a closed system of pumps and hydrocyclones in which the starch is separated from the fibres and washed out with fresh water. The fresh water consumption is reduced to about 200 l/t of potatoes. Quality and yield of starch are the same as in conventional processes.     

Application Possibilities of Potato Starch Process Water in Agriculture

The potato starch industry in the northeastern part of The Netherlands produces at present a very large amount of waste water. Research work is performed to solve the environmental problems resulting from discharge of this water into the canals. The development of a new starch washing procedure resulted in a considerably reduced water production and an economic production of potato protein. Land disposal is one of the possible means to purify the remaining process water. As in this water the elements K, N and P are present, in principle it can be used as fertilizer. The experimental results described in this paper demonstrate that sprinkling process water of the potato starch industry, with a mean yearly dose of 10 mm adjusted to an optimum utilization of the nutrient elements, gives a normal yield of agricultural crops and so saves fertilizer. Analyses of the quality of ground- and surface waters on the experimental fields show that the soil can completely purify such a small dose of process water. Model calculations indicate that the yearly costs will be Hfl. 2 per m³ process water and Hfl. 2.60 per t potatoes when the total water production is 1.3 m³ per t potatoes.     

蜡质马铃薯淀粉的性质及应用

蜡质马铃薯淀粉具有比普通马铃薯和蜡质玉米淀粉更为优良特性。具有糊化温度低、膨胀容易,糊化时吸水、保水力大,糊液的粘度很高、透明度非常好,平均粒径大、粒径大小分布范围广等独特性质,蜡质马铃薯淀粉在食品工业具有广泛应用前景。     

A New System for the Production of Starch and Protein from Potato

This article describes a technical system for the manufacture of starch, protein and fiber concentrates from potatoes without addition of process water. Because of a gentle drying, the excellent physical characteristics of the potato protein are maintained and make it applicable in foods. Chemical composition of the starch and protein has been examined. There seems to be good possibilities for application of the products. Calculations indicate a favorable economy using existing spray drying plants, which are idle in the potato season. Spray drying results in an increased energy consumption but this seems to be balanced by a larger product yield/t potatoes, the saving of waste water installations and the excellent physical and nutritional properties of the protein.     

紫薯淀粉结构与理化性质研究

目的 了解紫薯淀粉的结构和理化性质。方法 利用碱提取法从紫薯中提取淀粉, 与普通玉米淀粉进行对比, 分别对淀粉结构(分子链结构、结晶结构等)和理化性质(透明度、凝沉性、冻融稳定性、热稳定性)进行研究。结果 紫薯淀粉直链含量(24.5%)比玉米淀粉(26.7%)低, 两者均为A型结晶结构, 但紫薯淀粉的结晶度和分子有序程度比玉米淀粉高; 紫薯淀粉糊的透明度高于玉米淀粉糊, 且随时间延长其透明度下降程度比玉米淀粉糊低; 紫薯淀粉糊不易发生凝沉现象, 但其析水率(21.4%)比玉米淀粉糊高, 即冻融稳定性弱于玉米淀粉糊; 此外, 紫薯淀粉部分结构的热稳定性大于玉米淀粉。结论 紫薯淀粉在分子链结构和结晶结构上与玉米淀粉有较小差异, 但在理化性质上与玉米淀粉差别较大, 可为其工业应用提供指导基础。     

Potato Starch Technology

Potato starch production encountered drastic changes during the last years, in particular in economics and substrate supply. Because of economically required reductions in subsidisation, production of potato starch will decrease. Changes in technology are characterised by savings in wash water and process water streams that are effected by increased efficiency introduced with new machinery and changed technological concepts. From an ecological point of view, an early and maximum fruit water separation (up to 95 %) based on dilution of gratings with process water and decanter separation allowed to reduce the fresh water supply to 0.4 to 0.5 m³/t of processed potatoes. For economical isolation of potato protein a correspondingly high protein recovery rate (up to 90 %) is essential. Concerning starch extraction, a minimum of 95 % is reached in modern potato starch plants, but optimum engineering (rasping, decanting, sieving) gives recovery rates of 97 to 98 %. In starch refinement, three-phase nozzle separators equipped with wash water supply and constructed for efficient displacement washing allow to achieve a fine fibre removal of 98 % within three separation stages and a final concentration of purified starch milk of 22 to 23°Bé. Potato protein isolates (protein content 83 to 85 %) are produced by isoelectric precipitation combined with heat coagulation while stringent solutions for treatment of de-proteinised fruit water are still lacking.     

Five Years of Experience with the Application of Reverse Osmosis on Light Middlings in a Corn Wet Milling Plant

Corn wet milling is a water intensive operation. A modern corn wet milling plant typically uses 1,5 m³ of fresh water per t of corn. Much of this added water must subsequently be removed by processes that are energy intensive to varying degrees. A major breakthrough in reducing the water consumption of the corn wet milling process was made when A. Cicuttini perceived the idea of using reverse osmosis more upstream in the corn wet milling process, to recover pure water from light middlings, the overflow from the hydrocyclone starch washing system, and to re-use this water for starch washing. In doing so the direct relation between the amount of water used for washing the starch, and the amount of light steep water to be evaporated does no longer exist. A full size reverse osmosis system for this service has been installed in one of the CPC corn wet milling plants in 1982. In a first phase a reduction of the load to the steepwater evaporator of 50% has been obtained. Expansion of the reverse osmosis system enabled further reduction of the steepwater evaporator load down to 30% of the original value. The system has demonstrated its ability to operate in conjunction with a 9-stage starch washing section with a wet fresh water intake for starch washing, comparable to that of a 15-stage washing section, at the same high level of starch product quality, and at much lower energy cost. The disappearance of the direct link between fresh water consumption for starch washing and steep water evaporator load creates new possibilities for optimisation and flexibility in design and operation of corn wet milling plants.     

正交试验法优化马铃薯氧化淀粉制备工艺

使用正交试验法优化马铃薯氧化淀粉制备工艺,以马铃薯淀粉为原料,FeSO4为催化剂,H2O2为氧化剂干法制备氧化淀粉,并以羧基含量为评价指标,分别考察反应时间、反应温度、氧化剂用量、催化剂用量、体系含水量等因素对马铃薯淀粉氧化反应影响。得到最优工艺条件为:反应时间3.5h、反应温度60℃、FeSO4在淀粉中质量分数0.025%、H2O2与淀粉摩尔比0.285、反应体系含水量24.000%,在此条件下制得马铃薯氧化淀粉羧基含量为0.530%。     

基于数字图像分析技术动态监测淀粉糊化过程

采用一种基于累积光密度(IOD)值的数字图像分析技术的方法,动态定量监测500nm波长处,A型(玉米淀粉)、B型(马铃薯淀粉)、C型(豌豆淀粉)3种淀粉在过量水分含量体系中糊化时的结晶程度的变化情况;建立同一温度点下对应的DGI (IOD法对应的糊化度)和DGD(DSC法对应的糊化度)的直角坐标系,分析不同淀粉的糊化进程;绘制温度-IOD响应差谱图和代表淀粉糊化过程中结晶变化的响应强度的峰形图。结果表明：3种淀粉经历了不同的结晶程度从减弱到完全消失的历程,并且在糊化的不同阶段各有差异,同时糊化进程也差异明显。这种差异主要和淀粉的结构多样性与组成有关。     

Erfahrungen mit der Auswaschung von Kartoffelreibsel ohne Wasserzusatz

Experience in Potato Pulp Washing without Water Addition. In order to reduce the quantity of waste water from potato starch factories many have tried to keep the amount of water, required for washing out the starch from the pulp as low as possible. Our process is based on utilization of the water contained in the potatoes (approx. 80%, including soluble components) for starch extraction, in such a way that undiluted fruit water is separated and further treatment can be carried out in a comparatively economical way. Most of today's starch factories are tied up with production methods that make it impossible to utilize the water contained in the potatoes, as there is firstly no possibility of recirculating the fruit water and secondly there are foaming problems causing a negative effect on the efficiency. A continuous process guaranteeing a direct flow, excluding accumulation of foam, was installed and tested in both a Swedish and in a Dutch factory. The experience obtained showed that starch extraction with fruit water has no negative influence on the efficiency of the extraction (approx. 1 % free starch in the pulp DS/DS) and that up to 80% of the fruit water could be removed in a concentrated form. By extending the extraction process, and by using 300 l of process water from the refining section per ton of potatoes, separation of the fruit water can be increased up to 97%.     

淀粉分离旋流器液固两相流场的流体动力学研究

因为淀粉分离旋流器内部流体流动的复杂性,所以只能依靠实测研究和经验方程去预测和检验设备的性能,但这些方法无法从根本上解释旋流器分离机理.利用CFD分析软件对小直径的淀粉分离旋流器进行了仿真计算,采用RSM模型对单相流场进行了模拟,重点分析了流场的速度场分布情况以及旋流器内广泛存在的循环流现象;进而在单相流场的基础上采用MIXTURE模型对旋流器内液固两相流场进行了模拟,重点分析了旋流器内压降和进口流量之间的关系,并通过与以前的实测结果和经验公式的对比,验证了流场计算的可靠性.     

蕉藕淀粉与薯类淀粉特性对比研究

为探索蕉藕淀粉应用范围,选取木薯淀粉、马铃薯淀粉、红薯淀粉等薯类淀粉为对照,对蕉藕淀粉与常见薯类淀粉的组成、吸水(油)率、溶解度、膨胀度、透明度、凝沉性、凝胶强度、冻融稳定性及黏度等特性进行了对比分析。结果显示:蕉藕淀粉与常见薯类淀粉特性相比除吸水性差异不显著外,吸油率、溶解度、膨胀度、透明度、凝沉性、凝胶强度、冻融稳定性及黏度变化均存在显著差异,可利用蕉藕淀粉直链淀粉含量高、透明度好、凝胶强度高等特性,开发新型淀粉食品和增稠稳定剂。     

A New Hydrocyclone Process for the Separation of Starch and Gluten from Wheat Flour

A batter of wheat flour and recirculation water is directly introduced into a hydrocyclone system in which the prime starch is separated and washed out in countercurrent with fresh water. Agglomeration of the gluten takes place spontaneously in the hydrocyclones. The gluten agglomerates come free in the overflow of the system and can be separated easily by screening. The working of the hydrocyclones is not influenced by the presence of the gluten agglomerates. The total waste water stream is approx. 2 m³ per t of processed wheat flour.     

甘薯浓缩汁中淀粉的酶转化工艺研究

该研究立足国内丰富甘薯资源,解决甘薯浓缩汁中因淀粉引起沉淀问题,同时将甘薯淀粉转化为葡萄糖。以新型耐高温α–淀粉酶为液化酶和高转化率糖化酶糖化,研究影响甘薯淀粉液化、糖化因素,优化甘薯淀粉液化、糖化工艺参数。     

Effect of cooking time and ingredients on the performance of different starches in white sauces

The effect of white sauce ingredients and increased cooking time at 90 °C on the degree of gelatinization of corn, waxy corn, rice, potato and modified waxy corn starches was studied. The changes in pasting properties, linear viscoelastic properties, and microstructure were determined. In all the native starches in water, a longer cooking time at 90 °C caused greater starch granule swelling and more leaching of solubilized starch polymers into the intergranular space. These effects were more noticeable in the waxy corn and potato starches. The potato starch was the most affected, with complete disruption of the starch granules after 300 s at 90 °C. The microstructural changes which transformed a system characterized by starch granules dispersed in a continuous phase (amylose/amylopectin matrix) into a system with an increase in the continuous phase and a decrease in starch granules were associated with a decrease in system viscoelasticity. The elastic moduli were higher in the sauce than in the starch in water system. However, with the exception of potato starch, the white sauce showed lower viscoelasticity than the starch in water system. The white sauce ingredients decreased the effect of cooking time on the starch gelatinization process, particularly in potato starch.     

乌洋芋淀粉特性研究

揭示乌洋芋淀粉特性,为乌洋芋的产业化开发和高值化利用提供科学依据。利用SEM、粒度分析仪和DSC等研究乌洋芋淀粉的颗粒形态、粒度分布及糊化特性。3种乌洋芋淀粉颗粒多呈椭圆形,表面光滑,形貌大小不一,有脐点。粒径范围39．468～46．038μm;淀粉糊化热焓值4．902～5．829J／g;相变起始温度62．353～64．931℃、相变高峰温度65．173～67．703℃、相变终了温度70．437～72．890℃,均高于费乌瑞它淀粉。乌洋芋淀粉颗粒呈椭圆形,粒度分布均匀,糊化温度与普通马铃薯相近,具较好的开发利用价值。     

新鲜马铃薯渣同时制备膳食纤维和蛋白的研究

马铃薯渣是马铃薯淀粉生产过程中产生的一种主要成分是水、细胞碎片和残余淀粉颗粒的副产物,含有大量的淀粉和膳食纤维以及少量蛋白质,实际上是一种宝贵的资源。本文采用α-淀粉酶和糖化酶处理马铃薯渣,分离出的液态部分再经发酵培养出可供食用的蛋白质,固体部分经漂白、改性后成为膳食纤维,薯渣得到全利用。设计了工艺流程,对酶的选择和工艺条件作了优化。测定了产物蛋白质和膳食纤维的理化指标。     

New Developments in French Potato Starch Industry. Stone Removal Through Dense Medium Process,Environmental Protection

The French potato starch industry received a tremendous impetus since the beginning of the 19^th century. At that time it consisted of not less than 550 plants. At the beginning of the 20^th century it became greatly concentrated leading to a final number of five potato starch factories. The simultaneously increased production capacity has enabled the French potato starch industry to rise to the number two position among the potato starch producing nations of Western Europe. Closely connected with this concentration is a simultaneous modernization of the whole agriculture. All the five starch factories are located in the areas with vast cultivation plains where extensively mechanized agricultural operations are prevalent. However, as a result of this mechanization the deliveries of potatoes contain much larger amounts of earth and stones. For this reason a new process for the separation of stones is currently being tested, in order to reduce the up to now necessary amount of washing water by means of an enriched mud and to improve the effect of potato washing at the same time. The five French potato starch factories are equipped with total-continous and total-automatic machines, and they produce a high-quality potato starch. The concentration to large production units, however, has led in places to an increase of waste water amounts. According to official calculations the raining of potato fruit juice on large areas as well as use of aired ponds have led to a 90% superior purification. Protein recovery in connection with a decrease in waste water volumes will make it possible to even surpass the official standard of purification of 95%, approaching a purification effect of 100% in an already predictable period of time.     

Erfahrungen mit bekannten und neuentwickelten Maschinen in der Kartoffelstärkeindustrie

Experiences with Known and New Developed Machines in the Potato Starch Industry. With the aid of flowsheets a review is given of the new developments in processing and some new introduced machines, i. e. potato reception and washing installations, a new type of rasp, centrisieves as refining sieves for starch milk, decanters, rotary vacuum filters, and a new drum-belt press.