Entwicklungstendenzen in der Stärke- und Zuckerindustrie in Abhängigkeit vom Rohstoff. Teil 4. Kartoffel

Development Trends in Starch and Sugar Industries Depending on the Source Material. Part 4. Potato. In Western Europe (52°N. Latitude) the potential starch yield is estimated to be about 17 t ha⁻¹. For potato crops that can grow until October the average starch yield is estimated to be about 8 t ha⁻¹. The big gap between these two yields must be explained mainly by insufficient water supply to the potato crop. Also a more optimal quantity of foliage and possibly an improved type of haulm may help to bridge the gap. It is assumed that the starch yield will increase annually by about 100 kg ha⁻¹. The yield of coagulable protein is approximately 500 kg ha⁻¹. About the same quantity of N-compounds is processed with the cellwall material for fodder. It is shown that selection on starch yield is in general also a selection on protein yield. The energy output/input ratio for the production of 1 ha potatoes for the starch industry is about 2.5. It is likely that this ratio will increase.     

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.     

Entwicklungstendenzen in der Stärke- und Zuckerindustrie in Abhängigkeit vom Rohstoff. Teil 2. Mais

Development Trends in Starch and Sugar Industries Depending on the Source Material. Part 2. Maize. Due to progress in cultivation of maize the yield potential was annually increased by 1.2% from 1970 to 1976. This trend can be assumed to continue until 1985. By improving premature varieties it will be possible to extend cultivation areas. These varieties will be exclusively flint-dent if not only flint maize, and hamper the process in some starch factories. Apart from that, production costs for maize will rise drastically. Agriculture will hardly find a fruit which has such an ideal rotation of crops as maize. Due to progress in chemistry, however, rotation of cultures has become less problematic. Processers could well become interested in plants other than maize for the production of starch an sugar, e.g. wheat. Referring to this political decisions may have grave consequences. For instance from that point of views an opening of the Common Market to manioc could mean danger for starch production from european starch plants. Nevertheless one considers the fact that in the next 5 to 10 years Common Market countries will cultivate 3.5 to 4 million ha of grain maize.     

Gewinnung von Kartoffelstärke unter Verwendung des Abwassers als Düngemittel

Extraction of Potato Starch Utilizing Wastewater as Fertilizer . In Sweden the method of washing out the starch from the potato rasp with the undiluted fruit juice of the potato has been developed to higher yields of undiluted fruit juice. By concentration on a specially constructed vacuum filter followed by adding of water to the filter cake, the remaining fruit juice can be forced out, so that only about 0.03% N is left in the starch after filtration. This means that from the fruit juice of the potato about 20% remain in the pulp and about 78% in the fruit juice. The fruit juice is spread by vehicles in portions of 2.5–3 mm, what corresponds to about 100 kg N and 150 kg potassium/ha. The required area is about 130 ha/1000t of commercial starch. It was possible to reduce the amount of wash water to 50–100l/t of potatoes by recycling.     

STARCH AND PECTIC SUBSTANCES AS AFFECTED BY A FREEZE-THAW POTATO GRANULE PROCESS

Changes in total content and fractions of pectic substances and starch were studied in a freeze-thaw process for potato granule production consisting of peeling, steam cooking, hot mashing, freezing and thawing, pre-drying, granulation, drying, cooling and sifting. Pectic substances in raw potatoes (expressed as mg uronide/netted Gem 100g dry wt) were 202.4 for water soluble and only 80 for the calgon-soluble fractions. Water soluble pectic substances increased sixfold after cooking, and calgon-soluble fraction about threefold. Little change was observed in either fraction due to subsequent granule processing steps. There was no indication that pectic substances present in the extracellular matrix could have influenced the processing steps in granule production. Total starch comprised 68.4%/dry wt of raw potato, decreasing slightly after cooking, increasing up to the pre-drying step and stabilizing at a level of 83.7%. In contrast, free water-soluble starch, depended on the processing steps, being lower in cooked unmashed potatoes than in conditioned raw potatoes. Mashing slightly increased starch content while pre-cooling to 5.5°and freezing to −20°C with subsequent thawing to room temperature substantially decreased starch content. Mechanical forces applied in subsequent steps brought about some increase while in the final product the content was related to particle size of the granules. The percentage of broken cells in cooked potatoes mashed at various temperatures appears to be dependent on the free extracellular starch present in cell binding matrix. Broken cell counts were substantially decreased when mashing was performed immediately after cooking at high temperature or when the mash was frozen and thawed. In the latter case determination of Blue Value Index suggested that a decrease in cell binding strength of the matrix occurred due to soluble starch retrogradation.     

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%.     

Some effects of fibre and starch on the determination of protein quality

An assessment was carried out of the effects of an increase in the amount of fibre, as cellulose, and of a replacement of maize starch by potato starch in diets containing egg albumen as the sole protein, on the determination of true digestibility (TD) and biological value (BV). An increase in the fibre content of the diet at the expense of maize starch led to a rise in both fascal and urinary N excretion, with diets containing either 20 or 80 g egg albumen kg^?1. However, the response of the rats to increasing fibre concentration in the diet was different for the two levels of protein probably due to differences in dry matter intake (DMI). It was found that the conventional method of estimating metabolic faecal nitrogen (MFN) was not adequate for diets of decreasing digestibility; TD decreased by 0.35% for a rise of 1% cellulose in the diet. A more accurate method of estimating MFN was derived from a relationship between the N in the faeces and the digestibility of the diet. The increase in urinary N excretion led to a decrease of 0.41% in BV for a 1% rise in the cellulose concentration of the diet. It appears, therefore, that the ratio of digestible to indigestible matter in the diet affects the determination of protein quality. The replacement of maize starch by potato starch in the diet caused an increase in faecal N excretion and a decrease in urinary N excretion until a level of 200 g potato starch kg^-1 was reached. This affected the determination of TD and BV accordingly. An increase in the size of the caecum of the rats fed potato starch indicated that increased fermentation may have resulted in production of additional bacterial cells to be excreted in the faeces. Thus, both the amount of fibre and the type of starch in the diet affect the determination of protein quality.     

淀粉质原料在普鲁兰多糖生物合成中的作用及生理机制

为了考察不同淀粉质原料对出芽短梗霉生物合成普鲁兰多糖的影响,本文分别选用来源于木薯、玉米、马铃薯、红薯和小麦等作物的淀粉作为碳源发酵生产普鲁兰多糖。结果发现,木薯淀粉有利于普鲁兰多糖的生物合成,最高产量达到23.96 g/L;红薯淀粉则不利于普鲁兰多糖的合成,显著（P<0.05）降低了普鲁兰多糖的产量和分子量。进一步地,对普鲁兰多糖分批发酵动力学参数和生理学指标进行分析比较,发现木薯淀粉提高了普鲁兰多糖合成关键酶活性和胞内前体物质尿苷二磷酸葡萄糖的含量,进而提高了普鲁兰多糖的合成能力和产量;而红薯淀粉则提高了普鲁兰多糖降解酶活性,显著（P<0.05）降低了普鲁兰多糖的分子量。对普鲁兰多糖分批发酵碳源成本进行估算,发现利用木薯淀粉合成普鲁兰多糖的碳源成本只有葡萄糖对照组的56.6%。该研究结果为普鲁兰多糖的廉价高效生产提供了可行的技术参考。     

Starch from the Sago (Metroxylon sagu) Palm Tree—Properties,Prospects, and Challenges as a New Industrial Source for Food and Other Uses

ABSTRACT: The common industrial starches are typically derived from cereals (corn, wheat, rice, sorghum), tubers (potato, sweet potato), roots (cassava), and legumes (mung bean, green pea). Sago (Metroxylon sagu Rottb.) starch is perhaps the only example of commercial starch derived from another source, the stem of palm (sago palm). Sago palm has the ability to thrive in the harsh swampy peat environment of certain areas. It is estimated that there are about 2 million ha of natural sago palm forests and about 0.14 million ha of planted sago palm at present, out of a total swamp area of about 20 million ha in Asia and the Pacific Region, most of which are under‐ or nonutilized. Growing in a suitable environment with organized farming practices, sago palm could have a yield potential of up to 25 tons of starch per hectare per year. Sago starch yield per unit area could be about 3 to 4 times higher than that of rice, corn, or wheat, and about 17 times higher than that of cassava. Compared to the common industrial starches, however, sago starch has been somewhat neglected and relatively less attention has been devoted to the sago palm and its starch. Nevertheless, a number of studies have been published covering various aspects of sago starch such as molecular structure, physicochemical and functional properties, chemical/physical modifications, and quality issues. This article is intended to piece together the accumulated knowledge and highlight some pertinent information related to sago palm and sago starch studies.     

Beitrag zur mechanischen Entwässerung von Kartoffelpülpe

Contribution to the Mechanical Dewatering of Potato Pulp. In the Federal Republic of Germany 600 000 t potatoes yearly are processed by the domestic potato starch industries. This production results in large quantities of potato pulp as by-product which can be utilized economically to a limited extent only. The main field of application is the utilization as animal feed either in wet condition or after drying process. For this purpose, the potato pulp is dewatered mechanically and then dried preferably in flash-driers. As result of the mechanical dewatering of potato pulp even in most modern pulp presses and with extremely high pressures max. 25% d. s. are to be obtained only. In order to increase the mechanical dewatering effect an thereby to decrease the energy expenses of the following thermal dehydration attemps have been made to disintegrate the potato pulp to the most possible extent by an alternative chemical or enzymatic pretreatment. When using kieselguhr the dewatering effect could be increased by around 5% from 26% d. s. to 31% d. s., whereas the application of calciumchloride effected an increase of almost 11% from 29% d. s. to 40% d. s. Under the test conditions also the application of pectolytic enzymes in liquid form increased the yield by 10% d. s.     

制备条件对微晶淀粉结构的影响研究

酸解淀粉经过脱支化作用后,可以有效改善酸解淀粉的结晶能力,较大程度地提高微晶产品的结晶度。经脱支化处理得到的样品,其结晶行为与仅仅经过酸解的淀粉的结晶行为一样,它们在冷冻条件下都形成B型结构。在其他制备条件相同时,随着酸水解时间的延长,玉米淀粉微晶的收率越来越低,而马铃薯淀粉微晶的收率则越来越高。玉米淀粉和马铃薯淀粉分别酸解12d和20d时所得微晶的结晶度最高,分别为80.19%和71.12%。脱支化处理及酸解时间的长短对微晶的峰值聚合度影响较小。     

扫描电镜和稳定碳同位素比质谱法鉴别马铃薯淀粉中的掺假玉米淀粉

为有效辨别食用淀粉掺假,运用扫描电镜和稳定碳同位素比质谱技术对马铃薯淀粉中掺假玉米淀粉行为进行定性和半定量鉴别。根据马铃薯淀粉与玉米淀粉在颗粒超微形貌上的明显差别,运用扫描电镜清晰辨别出马铃薯淀粉中掺假的玉米淀粉颗粒。当玉米淀粉的掺假量大于10% 时,根据二者在稳定碳同位素比上的自然显著差异,稳定碳同位素比法不仅能够定性鉴别马铃薯淀粉中的玉米淀粉掺假行为,而且依照给出的公式可以估算出掺假玉米淀粉的含量。本法可作为国内淀粉市场上产品质量监督的检测方法。     

Agronomic Factors Related to the Quality of Wheat for the Starch Industry. Part I: Sprout Damage

The wheat starch industry in the Netherlands processes about 300.000 t of wheat annually. However, only a small percentage of this wheat is grown in the Netherlands although it has been demonstrated that Dutch wheat varieties can also be successfully processed. Climatological and cultural aspects can however negatively affect Dutch wheat quality. Due to climatological conditions the Dutch wheat regularly suffers from sprout damage. It is for this reason that the effects of sprout damage on processing quality and quality of gluten and starch have been investigated using a pilot scale gluten starch separating system. Low levels of sprout damage appeared to have no effect on gluten yield and even improved the gluten coagulation. In baking tests also no effect of sprout damage on gluten quality could be detected. On the other hand, low levels of sprout damage may lead to a lower starch yield and starch has low viscosity characteristics, limiting its scope of application. Also the amount of solubles in the waste water was increased. These findings lead to a further definition of requirements of wheat for the starch industry, enabling future selection of wheat on the basis of more accurate criteria.     

Effect of peeling and unpeeling on yield,chemical structure,morphology and pasting properties of starch extracted from three diverse potato cultivars of Pakistan

The current study investigates the comparison and quality characteristics of starches isolated from potatoes using different processing methods from three commercial varieties: Lady Rosetta, Asterix and Challenger, for the first time in Pakistan. The analysis of variance revealed that starch yield significantly (P < 0.05) depended on total solids, peeling (12.7%, 12.0% and 12.0%) and unpeeling (15.0%, 14.0% and 14.0%) of potatoes compared to potato varieties for Lady Rosetta, Challenger and Asterix, respectively. Moreover, pasting properties, protein content, redness and yellowness were increased in those starches isolated without peeling while carbohydrates and lightness were increased in peeled potato starches. Furthermore, Fourier-transform infrared spectroscopy analysis revealed that protein (1200–1400 cm⁻¹) was present in starch extracted without peeling. Besides, scanning electron microscopy analysis revealed oval-shaped starch granules with no impurities in peeled potato starch. The findings suggest the suitability of peeling process for obtaining a high-quality pure starch.     

Untersuchungen über den Einfluß der organischen und mineralischen Düngung auf die Viskositätseigenschaften der Kartoffelstärke

Studies on the Influence of Organic and Mineral Fertilization on Viscosity Properties of Potato Starch. In trying to solve the question, whether through mineral fertilization a specific potato starch quality can be established in the field the special significance of year-round climatic conditions, location of cultivation and variety for pasting temperature, hot viscosity and cold viscosity of the potato starch became apperent. Compared to these influences, that of mineral fertilization was minimal. It was shown that the factors of starch quality were only to be positively influenced, however slightly, on a long-term basis through increase of the P₂O₅-content of the soil. Thus, aimed production of specific starch qualities is not possible through fertilization. This means that breeders of starch potatoes ought to adjust mineral fertilization to optimum yield of tubers and starch.     

Der Energieaufwand in der Reibenstation bei der Kartoffelstärkefabrikation

The Energy Expenditure in the Rasp Station of Potato Starch Production. Three different types of potato rasps being used in Polish Starch Industry were tested: ZT-300 “Spomasz” (Poland). Holthuis (Holland), RU 80-500 Nivoba (Holland). Optimum throughputs depending on energy consumption per one ton of potatoes and disintegration factor were determined. The results confirmed the assumption that increase of throughput decreases electrical energy consumption, however is restricted by disintegration efficiency (factor min. 90%). The latter effects quantity of bound starch on potato pulp and yield of potato starch recovery at the same time. The optimum throughputs for the three rasps were determined.     

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.     

Small Diameter Multiple Hydrocyclone for Starch Processing

The traditional application of small diameter multiple hydrocyclone batteries in the starch industry is the refining of maize, wheat, potato, and manioc starch by countercurrent washing in multistage operation. A new type of multiple hydrocyclone battery for these purposes is discussed. Construction details, internal flow passage, selection of construction material, and some operational characteristics of the battery are taken into consideration as well as its easy, handling. As an example of application of a small diameter hydrocyclone system, a new process alternative for manufacturing of potato starch is presented. The process has a fresh water consumption for starch extraction and refining of 300–350 l/t potatoes or ∼ 1.9 – 2.2 t of water per ton of refined DS starch, due to the unique combination of process stages by adapting a hydrocyclone system, screens, and centrifugal separators.     

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.