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1.
Processes of Industrial Wheat Starch Production on Source Material Basis Whole Wheat In this contribution six of all in all 15 different procedures of industrial wheat starch production are described. These 15 procedures can be classified either on the basis of the two possible source materials whole wheat and wheat flour or with regard to the separation technique in mechanical, chemical and fermentative separation. One more classification can be related to the by-product wheat gluten which can be obtained either as vital or devitalized gluten. In this contribution the classification of the production processes is refered to the two possible source materials whole wheat and wheat flour. Six of the all in all 15 procedures are based on the source material whole wheat. Finally, a modified Longford-Slotter-process is presented which is introduced by laboratory steeping of unmilled wheat with addition of 0.2% sulphur dioxide for 15 h at 37°C. After this modified Longford-Slotter-procedure it was possible to yield by only one discontinuous centrifugation and only one tabeling 54% starch with 0.4% crude protein content which corresponds to a recovery rate of almost 81%. 相似文献
2.
Properties of Triticale Starch Refered to Polish Triticale Varieties. A high content of starch in triticale grains makes us suppose that this cereal may also be a good raw material for starch industry. To be able to answer this question studies were conducted on many Polish lines and varieties with respect to more important physico-chemical properties of their starches, such as graininess, water binding capacity, solubility in water and pasting characteristics. Studies have shown that starches of many investigated lines and varieties of triticale are characterized by properties of interest for starch industry. Compared to wheat triticale seems to be a good raw material for food industry and particularly for starch industry. This view finds support in high yields of grain and starch as well as good graininess, viscosity of starch and high degree of purity. 相似文献
3.
Paperchromatographic Separation as Identification Method of Native and Modified Wheat Starch . The previous experiences with paperchromatographic separation as identification method of native and modified starch samples has been useful in the study of wheat starch. This technique has been applied to the separation and identification of amylose and amylopectine of native and modified wheat starches (treated by phosphate, mineral acids and different temperatures). The results thus obtained were compared with the physico-chemical characteristics of the same material. The modification procedure and the temperature influence are precisely outlined. The evaluation of the final data permits one to judge the applied technique favourably, the method can be considered as useful and complementary in the analysis of starch material. 相似文献
4.
Abdulvahit Sayaslan 《LWT》2004,37(5):499-515
Commercial manufacture of wheat starch and vital wheat gluten involves physical separation of starch granules and gluten particles formed in a neutral aqueous system. The wet-separation of gluten proteins and starch from wheat flour is based on their water insolubility, density, and particle size. Upon wetting, gluten proteins in wheat endosperm aggregate and form particles that are larger in size but less dense than starch granules. Wheat starch and vital gluten are currently produced industrially through wet-milling of wheat flour principally by four processes; the Martin, Alfa-Laval/Raisio, Hydrocyclone, and the High-Pressure Disintegration (HD) processes. The industrial processes differ mainly in the forms of the flour-water mixtures presented to the fractionation equipment (centrifuge, hydrocyclone, or screen) or in the initial separation practice of starch and gluten fractions from flour. However, the processes essentially merge into one as the intermediate starch and gluten-particle streams are purified to give >98% pure starch and ∼80% protein vital gluten. Handling of a second-grade starch stream, flour water-soluble, and fibrous residues may differ at various processing steps. Small-scale tests are available to assess the wet-milling quality of flours to be wet-processed by the Martin, Batter, Alfa-Laval/Raisio, and the HD processes. Yet, there are no laboratory tests reported for the Hydrocyclone process. Given the development of numerous new wheat varieties each year and of high-amylose and waxy wheats, it is important that small-scale wet-milling tests to assess the wet-milling quality and suitability of flour samples for the industrial processes be available. 相似文献
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6.
Removal of Waste Water from Wheat Starch Industry – An Economic Comparison. The portion of wheat starch production in the total production of starch out of corn, potatoes and wheat was only of minor importance in the past. Based on new process engineering for the production of wheat starch as well as EC market regulations the production of starch from wheat or wheat flour recently appears more interesting. Due to higher outputs in wheat starch plants there is a demand in methods for waste water engineering alternative to agricultural utilization of waste water. The completely biological waste water treatment in an aeration basin, the evaporation, filtration, protein coagulation. sale for cattle fodder, fermentation, and the anaerob purification are to be indicated. It does not only depend on the process engineering and the efficiency but most essentially on the economic efficiency which of these methods of waste water treatment will prevail in large-scale technique. The anaerobic waste water treatment of highly organic load waste water recently comes to the force more and more. A comparison of the different methods for waste water treatment shows that the charges very much depend on the waste water factor, i. e., the quantity of waste water per ton processed flour and the charges for electricity and fossil sources of energy. The calculation of the charges has to include the charges for an advanced waste water treatment in a sewage treatment as well as the profit for the digester gas or the concentrate. 相似文献
7.
W. Kempf 《Starch - St?rke》1972,24(8):269-275
Processing Properties of Local Maize. 2. Starch Production . Since the results of numerous preliminary tests have clearly demonstrated that compared with oversea maize samples also French yellow maize varieties under certain conditions and in parts even with same satisfactory results proved to be quite suitable as source material for starch manufacturing process, the general quality and analytical composition of all in all 30 different varieties of French yellow maize cultivated in the two Bavarian areas of Weihenstephan and Strassmoos and their extractable recoveries of starch, gluten, germs, fibre and steep-water dry-matter as well as their processing properties were determined. From these all in all 30 samples the results of analytical examinations and recovery determinations obtained from only eleven different varieties of French yellow maize cultivated in the Bavarian area of Weihenstephan were compared with the correspondent results obtained from another eleven samples of yellow maize from various French departments as well as from further eight overseas samples of yellow maize and white maize from Argentina, South Africa and U.S.A. and one additional sample of Roumanian yellow maize. 相似文献
8.
Possible Standardization of Viscosity Measuring Procedures for a Comparative Valuation of the Rheological Properties and Behaviour of Starches . As generally known, in both starch research and starch industries numerous different apparatus for viscosity measurement are used which produce rheological data by the scale and measuring systems of the instruments applied. However, the test-data obtained can not be compared on principle because of those different scale and measuring systems fixed to each instrument. Furthermore, no suitable procedure as standardized method is availably up to now. The standardization of suitable methods on the other side presupposes that the apparatus for viscosity measurement themselves produce reproducible results when uniform working directions are used. For that reason the viscosities of various potato, maize, rice and wheat starches were determined under different test conditions by utilizing the Brabender viscograph, Rotovisco instrument and Hoeppler falling-ball viscosimeter in order to establish optimum conditions for the reproducibility of results obtained. Thereby those three apparatus for viscosity measurement were selected in particular under technological aspects of application. As result of the comprehensive investigations it seems to be quite possible to criticize and review comparatively the rheological properties and the rheological behaviour of starches with regard to their importance in the special field of technical application, if the existance of suitable and also standardized methods guarantees a sufficient reproducibility of the test-data. 相似文献
9.
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. 相似文献
10.
H. Brandenburger 《Starch - St?rke》1978,30(11):365-366
Development Trends in Starch and Sugar Industries Depending on the Source Material. Part 3. Wheat. Soft wheat is a kind of grain with a high assimilatory effect and high genetic yield potential. With no other variety can yield and quality be manipulated in order to render scientific-technological progress fully effective. Cultivation and harvest can be mechanized to an extent that always keeps production costs favourable – compared to other grain varieties. Wheat is without problems in storage and conditioning. There are no technological difficulties. Wheat, as mass producer of assimilation products, is a plant with a future. Nutrition of the world population is greatly connected with this grain variety, but also supply of the raw material industry with starch products for technological purposes will gain more significance. 相似文献
11.
W. Kempf 《Starch - St?rke》1979,31(12):397-404
Dynamic Development of Starch Research and Starch Industry in Japan Refering to two lectures and visiting tours throughout Japan in 1962 and 1978 the dynamic development is indicated which has taken place in the Japanese starch research and Japanese starch industries within the past 16 years. In this connection the annual production figures as well as the most important field of applications for white potato, sweet potato, corn, and wheat starches are reported. Correspondent data are also made for starch saccharification products, whereat particular consideration is directed to the industrial production and marketing of high fructose syrup. As far as the starch research is concerned, the tremendous investments are emphasized which recently have been increased to a considerable extent. In this connection it is concluded that the remarkable progress which has taken place in both the Japanese starch research and Japanese starch industries obviously are based on two main factors. One of these two factors seems to be the almost unlimited financial possibilities of both government and industries, whereas the other one is connected with the extremely expressed working discipline of the Japanese employees. The great progress gained by the Japanese starch research as well as by the Japanese starch industries particularly within the past decade are not only very impressing, but at the same time also rather depressing with regard to the limited possibilities in the Federal Republic of Germany. 相似文献
12.
H. Scherz 《Starch - St?rke》1975,27(2):46-51
Radiolysis of Starch. A Contribution to Quantitative Determination of Several Radiolysis Products in Potato Starch and Wheat Flour . The amounts of formed desoxy-compounds, which produce malonic dialdehyde during HI O4-oxydation, as well as that of ω-hydroxymaltol have been determined in irradiated potato starch and irradiated wheat flour in dependence on irradiation doses. With pure potato starch, G-values*) of 0.03–0.04 for water soluble desoxy-compounds and such ones of 0.02 for insoluble desoxy-compounds were obtained. G-values of desoxy-compounds in an ethyl acetate-acetone-water extract (4: 5: 1 v/v) of irradiated potato starch and irradiated wheat flour showed a ratio of about 3: 1. When aqueous potato starch sols are irradiated desoxygroups in the high-molecular starch molecule will also be found (in N2O atmosphere: G-values around 0.3). With ω-hydroxymaltol it became apparent that the main part of this compound is formed after irradiation during storage. With pure potato starch G-values around 0.015–0.02 were determined after 10 days of storage. When this material is heated after irradiation an increase of the hydroxymaltol content (G-values: 0.025) is to be found. In the non-irradiated materials traces of desoxy-compounds as well as ω-hydroxymaltol were found. 相似文献
13.
W. Kempf 《Starch - St?rke》1978,30(8):254-256
Development Trends in Starch and Sugar Industries Depending on the Source Material. Part 1. Introduction. In the first part of the introduction to the symposium solar energy radiated to earth and its effects on the photosynthesis as well as the possibilities of an improved utilization of surplus solar energy are discussed. Possible yield increases of grain in general and of wheat in particular as well as a parallel possible increase of starch production are subjects of discussion in the second part, where recovery and marketing of the by-products are taken into consideration, too. As far as new developments on the specific field of enzyme technology are concerned, in the third part the possibilities of converting starch into a large number of so-called agrochemicals as source materials for chemo-technical industries by application of immobilized enzymes as biocatalysts are discussed. In consideration of the points of view as mentioned, in the fourth and last part of the introduction the following separate contributions are introduced as an attempt to indicate possible and also realizable developments in both starch and sugar industries with specific consideration of the respective source materials available. 相似文献
14.
Investigations on the Retrogradation in Concentrated Wheat Starch Gels. Part 2. Effect of Starch Degradation Products on the Starch Retrogradation . In the present work the influence of added starch degradation products on the rigidity and retrogradation of 50% wheat starch gels was investigated. The gels prepared with the addition of maltodextrin were extracted with 40% ethanol, the extracts were analysed for glucose oligomers. The effect of the added starch degradation products was dependent on the degree of degradation. Weakly degraded, acid modified starches take part in the retrogradation process as do white and yellow dextrins as well as maltodextrins with dextrose equivalents (DE) <30. Maltodextrins and glucose sirups with a DE ≧ 30 act as plasticizers: in concentrations of 5-30% (based on starch d. s.) they reduce gel strength without affecting the retrogradation velocity. The plasticizing effects are particularly evident with maltose and maltotriose as well as maltotetraose and pentaose. Even so the extractibility of oligomers with a degree of polymerisation (DP) ≥ 6 was reduced, the hexamer and octamer might still have a plasticizer effect. With glucose, concentrations ≥ 26% were needed to observe plasticizing. The relation of these findings to bread staling is discussed. 相似文献
15.
On the Problems of Ultrafiltration of Wheat Starch Processing Water . The problem of recovery of soluble substances from process water in wheat starch production compared to the starch production from corn and potatoes are mentioned. Membrane filtration was tested on a pilot scale level to recover the soluble substances of wheat flour. It was found that the flux rates of tested membranes were not affected by their structures. They depend upon the building of a gel type layer near the membrane surface. In the tubular modules the building of that layer could be affected to a certain degree by changing the flow characteristics. Besides the flux rates the retention capacities of different membranes — membranes for ultrafiltration and reverse osmose — were studied. It was found that the chemical oxygen demand (CSB) of the permeate was proportional to CSB of the retentate. With the help of experimental results the cost of membrane filtration in combination with the concentration of the retentate by evaporation compared to the cost of evaporating whole of the process water was estimated. It was concluded from this that the membrane filtration is not economical for the process water of wheat starch plant at present as the cost of equipment is high because large membrane surface is needed as the flux rates are low. 相似文献
16.
The Influence of Extrusion Parameters on the Functional Properties of Wheat Starch. The functional properties of native starch can be altered by regulating the technical parameters in the extrusion cooking process. The influence of specific variables on the resultant starch properties can be differentiated by means of system analysis. To make this clear, a model has been put forward which divides individual factors into those which influence the process and those which are influenced by the process, as well as examining their interrelationships. As a result of the experiments, it was possible to use regression analysis to examine the relationships between the various system analysis components. Thus it is possible either to predict the properties of the resultant starch knowing the extrusion and system parameters, or to suggest suitable extrusion conditions in order to obtain a particular starch product. 相似文献
17.
Zongyuan Jiang Qingjing Liu Xiaoling Zhou Xianghong Li Faxiang Wang Yongle Liu 《International Journal of Food Science & Technology》2021,56(2):794-803
The starch physicochemical properties of wheat varieties used to commercially produce dried noodles were studied. Scanning electron microscopy and laser microparticle size analyser were used to observe the starch particles; the polymorphism of the waxy (Wx) protein of each wheat variety was also studied. The correlation analysis among commonalities of the starch physicochemical properties and noodle textural properties was performed. Results indicated that the amylose contents of the noodle wheat varieties ranged from 17.8% to 21.7%. There was a significant, positive correlation between the thermodynamic temperature of starch and the volume distribution of particle size. The correlation between the volume distribution of B-type starch granules and noodle springiness was significant, which means that volume distribution of starch particle size could be used as one of the indicators to evaluate the springiness of noodles. Molecular polymorphism identification of Wx protein was also useful to select desirable noodle wheat variety. The results of this study provide useful information for wheat breeding works and wheat variety selection of noodle-making company. 相似文献
18.
Starch and gluten were isolated from flours milled from 21 Australian wheat varieties. Relative yields of starch and gluten varied in general accord with flour protein content. Recoveries of total solids (starch plus gluten) ranged from 67.6% to 85.1% amongst the varieties. Significant differences in proximate composition and amylose content were observed between the isolated starches. This was especially so for starch protein content which was significantly correlated with wheat hardness. Potential benefits exist for the starch/gluten industry in selecting wheats on the basis of minimal loss of total solids during the process, and for purity and amylose content of the isolated starch. 相似文献
19.
F. Dud 《Starch - St?rke》1976,28(4):127-129
Influence of Stirring and Dissolving Time on Accuracy of Starch Determination According to Ewers in Cereal and Milling By-Products. From chemical analyses and their statistic evaluation it is seen that stirring during starch dissolving is indispensable for accuracy and good reproducibility of results during starch determination. Stirring of the sample according to the commonly applied technique can be recommanded as the most suitable method. Besides stirring it is most important to keep the exact time for starch dissolving. Even though with wheat fodder flour the highest starch content was found after dissolving time of 18 min, it is recommended not to exceed 15 min as the higher starch content is probably simulated by partly hydrolysis of pentosanes, hemicelluloses and also cellulose which become concentrated in the milling by-products. 相似文献
20.
On the State of Knowledges Concerning the Processes During Staling of Starch in Baked Goods. 1. The present level of knowledge on staling of baked goods is discussed shortly on the example of most essential theories. 2. Research into the problem of staling of gels of wheat starch or wheat flour was performed viscographically and ridgelimetrically. 3. The photometric titration with iodine and the paper elution analysis with perchloric acid are recommended as new methods for a separated characterization of the starch constituents during staling. 4. In the staling of baked goods, the changes of starch play a predominate role, the swelling condition of the starch granule and the chemo-physical and chemo-colloidal behavior of the two starch constituents being decisive factors. 5. The natural fat content of flour or the addition of saccharose monostearate counteract the hardening of the corresponding gels, caused by staling, by inhibiting the swelling process of the starch granules and the effect of amylose on the formation of structure. 相似文献