bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation of the dynamic behaviour of packaged products
Authors: Du Pré W. C.
Published: November 2006

A brief historic overview is given of simulation research in the TNO Packaging Research Centre, starting with ideas initiated some 5 years ago and ending with those being considered today. Some of the increasing number of simulation tools available are discussed, and a few thoughts are presented for prospective users making an intelligent choice.

The paper presents what the TNO Centre for Packaging Research tries to simulate at present, and then considers why and how such simulations are carried out.

Developing simulation techniques is a long‐term commitment and it should be realized that only by performing such simulations is it possible to find out what is possible, affordable and practical.

Sometimes the applicability of new techniques can be discussed successfully with representatives of the target group only if a few examples are shown to them.
Packaging aspects of high‐pressure food processing technology
Authors: Mertens Bart
Published: November 2006

High‐pressure (HP) technology is a novel, non‐thermal food preservation and processing technology whereby food is subjected to high isostatic pressure (100–600 MPa) at or around room temperature. This paper discusses the compatibility of HP technology with existing food packages, packaging materials and closures. Based on literature data and our own research data it is shown that:

Container‐lid combinations, which have sufficient flexibility to compensate the limited compression of the food and the complete compression of air at these high pressures, can be HP treated without physical damage;

Mechanical properties and barrier properties of multilayer plastic and aluminium foil packaging materials are not affected;

HP does not influence migration

Heat‐seal strength and integrity also are not affected

It is concluded that packaged foods can be HP treated and that HP opens up new possibilities to make plastic packaging less expensive and more environmentally friendly.
Quantification of the UN leakproofness test method
Authors: Schilperoord A. A. , Schets M. A. A. M.
Published: November 2006

In this paper a theoretical model is described for the UN leakproofness test, which is one of the test methods of the UN test programme for the type testing of packaging for liquids for the transport of dangerous goods. The test is also required for every single packaging produced. Quantification was thought necessary in order to be able to evaluate production line leakproofness test methods which should be as effective.

The model was verified with an experimental programme which was performed with leaks of the pinhole type.

The results show that the process of bubble formation and flow of the UN leakproofness test method can be modelled assuming laminar flow and taking into account capillary pressure and bubble frequency. For a leak of the pinhole type and a realistic set of parameters the detection limit of the method can be indicated as being in the order of 20 μm of hole diameter.

It is discussed whether analysis of the concept of leakproofness testing might be necessary.
Anhydrides as antimycotic agents added to polyethylene films for food packaging
Authors: Weng Yih‐Ming , Hotchkiss Joseph H.
Published: November 2006

Incorporation of free acids or salts of antimycotic food additives, including propionic acid, benzoic acid or sorbic acid, into low‐density polyethylene (LDPE) films failed to inhibit mould growth when the films contacted inoculated media. However, LDPE films into which benzoic anhydride was incorporated exhibited antimycotic activity when in contact with media and cheese. Benzoic anhydride, which had been added to LDPE film, was hydrolysed within 5h and detected as benzoic acid in potato dextrose agar (PDA) and cheese after contact with the film. LDPE films, into which 1% benzoic anhydride was incorporated, completely inhibited Rhizopus stolonifer. Penicillium spp., and Aspergillus toxicarius growth on PDA. Lower amounts of anhydride partially inhibited growth by increasing the lag phase and reducing the rate of growth in most cases. LDPE films incorporated with 0.5–2% benzoic anhydride delayed mould growth on cheese. These data suggest that addition of antimycotic agents to LDPE during film manufacture may be a feasible way of controlling surface mould growth in foods such as cheese.
Model of respiration for fresh produce in closed systems: 1. Evolution of oxygen in the case of tomatoes
Authors: Brion J. , Daumont D. , Malicet J. , Augusto C. , Pasca B.
Published: November 2006

A model describing the O2 consumption by fresh produce in a closed system is proposed. The model uses a matrix representation as a new mathematical interpretation based on a physiological approach, in agreement with the observed phenomena but contrary to current models. This is a prime condition necessary to elaborate a more complete model concerning the behaviour of fresh produce packaged under modified atmospheres. Such a model is under study at this time.
Packaging and world class competitive products
Authors: Fowler Dudley
Published: November 2006

The aim of the Irish food industry is to produce world class competitive products (WCCPs). Stating the obvious: Food and packaging are inseparable and thus WCCP status is a target also for packaging manufacturers in their own right and also as to how packaging assists food companies to achieve their aims.
Quality of food contacting materials with respect to migration: An advanced testing methodology applied during microwave heating
Authors: Lox F.
Published: November 2006

The UV methodology previously outlined has been applied to assess the influence of microwave heating on the migrational behaviour of plastics. Because the method indicates the way migration changes as a function of t when measured at constant temperature, its exponential relationship as a function of temperature (t) can be evaluated as well. Hence, the behaviour as a function of time while temperature changes are taking place can be calculated.

In the current experiments the migrational effects of PET in water were studied as the temperature was raised by microwaves. No influence due the microwaves was found.
News of recent packaging developments in Greece
Authors: Karakasides N. G.
Published: November 2006

During the past decade, there has been a growing demand for newer types of packaging in Greece. Packaging manufacturers have modernized and expanded their capabilities and developed new high‐technology products which may contribute to improved environmental protection. This review outlines recent developments and trends in Greek packaging usage.
Transit packaging—a global view
Authors: Starkey W. G.
Published: November 2006

In any large multinational Corporation responsible for the movement of finished equipment on a global basis, the logistics problems created can be daunting. This paper outlines how we endeavour to minimize the risk of in‐transit damage by the use of laboratory test facilities during the design phase of a new product—this could be 3 years prior to launch.

First, however, we have to examine the current logistic patterns of our equipment movements. This paper illustrates some of the problems and pitfalls presented to the packaging designers of a large corporation. The challenges are nearly always fun to overcome, and with the ever‐changing distribution patterns and the introduction of new technologies we can never afford to be complacent.
Estimation of the biodegradability of packaging materials by a screening test and a weight‐loss method
Authors: Coma V. , Couturier Y. , Pascat B. , Bureau G. , Guilbert S. , Cuq J. L.
Published: November 2006

Two methods were studied in order to estimate the degradability of packaging materials, using cellulosic materials—such as cellophane or paraffin waxed paper—as models. A preliminary orientation test was carried out, based on the visual observation of microbial development on the materials used. This qualitative test permitted an initial classification of materials according to their potential degradability, and especially allowed the identification of microbial species, particularly fungi, most likely to grow on the materials being studied.

The biofragmentation of materials was evaluated from their dry weight loss. For a fixed time of incubation, the classification of these materials was based either on the percentage or on the absolute value of this weight loss. For the method applied to a solid medium, we found that an inoculum deposited on an agar surface was more suitable than direct inoculation of the samples, in fact, pure fungi strains, especially Trichoderma viride or Aspergillus niger, were found to be more suitable for cellulosic materials than the bacterial strains (Pseudomonas fluorescens) or bacterial mixture used.
Biodegradability of packaging materials using a respirometric method
Authors: Coma V. , Couturier Y. , Pascat B. , Bureau G. , Guilbert S. , Cuq J. L.
Published: November 2006

To measure the biodegradability of packaging materials, a scientific and methodological approach is proposed, using the results obtained with cellulosic materials as models. Their degradation was evaluated using a respirometric method based on the measurement of CO2 released by microorganisms (Pseudomonas fluorescens and a mixture of cellulolytic bacteria). Our study was conducted in confined conditions, and the CO2 released was detected by gas chromatography (GC). Glucose was used as a reference compound because of its complete bioassimilation by the strains studied. The percentage of carbon converted into carbon dioxide was the parameter used to classify materials according to their potential biodegradability. With both inocula, the percentage of absolute conversion of glucose to CO2 reached about 36% compared with 24% and 13% for the hydrated crystalline cellulose and the paraffin waxed paper, respectively. Measurements of the percentage of absolute conversion of glucose to CO2, of the dissolved carbon in the culture medium, of the biomass carbon and of the residual glucose permitted the calculation of an approximate carbon balance with Pseudomonas fluorescens. The percentages of absolute and relative conversion of packaging materials into CO2 were calculated and the growth rates evaluated. It was shown that to evaluate the biodegradation of insoluble substrates, the biomass produced and the dissolved carbon must be taken into account.
Integral approach for optimizing modified atmosphere packages for elstar apples: A combination of product and packaging constraints
Authors: Evelo R. G. , Boerrigter H. A. M.
Published: November 2006

Modified atmosphere packages with Elstar apples in various packaging systems have been investigated. Loss of firmness during shelf‐life is used as the quality aspect to judge the performance of the modified atmosphere packages. A system‐oriented model is derived that describes the experimentally found concentrations well. In the overall approach the time dependency of the oxygen and carbon‐dioxide concentrations are discussed. It is shown that the quality attribute, the softening of apples, can be affected by the choice of packaging material. Hence this approach can be used to optimize modified atmosphere packaging of Elstar apples.
Influence of sorbed vegetable oil and relative humidity on the oxygen transmission rate through various polymer packaging films
Authors: Johansson F. , Leufvén A.
Published: November 2006

In this study, the effect of a vegetable oil on the oxygen barrier properties of different polymer packaging materials [i.e. amorphous polyethylene terephtalate (APET), polypropylene (PP) and high density polyethylene (HDPE)] was investigated. The influence of both relative humidity and the combination of relative humidity and sorbed oil on the oxygen transmission rate (OTR) was studied. Regardless of the relative humidity, the APET film remained an excellent oxygen barrier even after storage in rapeseed oil for 40 days. An increased OTR was observed in both the PP and HDPE films stored for 40 days in rapeseed oil. The OTR of the HDPE films was altered to a much greater extent than the OTR of the PP film. The OTR of the HDPE film was also significantly increased for films stored for 20 days in rapeseed oil. The increase in OTR of an HDPE film stored for 40 days in rapeseed oil was between 36 and 44%, depending on the relative humidity, compared to the OTR through the virginal polymer. The amount of oil sorbed by the polymer films used decreased in the following order: HDPE ≫ APET > PP.
Effect of specimen size on test results to determine cushioning characteristics of corrugated fibreboard
Authors: Naganathan Prabakaran B. , Marcondes Jorge A.
Published: November 2006

This paper investigates the shock absorption properties of corrugated fibre‐board when impacts occur on test specimens of different sizes. In particular, the effect of two types of specimen is studied: (1) a circular specimen of the same size as the flat bottom surface of the drop hammer and (2) a rectangular specimen larger than the contact area of the impacting hammer.

This study was conducted as a preliminary investigation of the significance of the cushion areas adjacent to the area in contact with the drop hammer, since this occurs in most cases in practise when packaged products rely on the shock absorbing characteristics of the corrugated fibreboard.

The results show that the effect is significant and suggests that the use of traditional cushion curves for corrugated fibreboard be re‐evaluated.
Process of contaminant transfer through a food package made of a recycled film and a functional barrier
Authors: Laoubi S. , Vergnaud J. M.
Published: November 2006

The process of the transfer of a contaminant through a package made of a recycled film in good contact with a virgin film playing the role of a functional barrier is studied. The two films being made of the same polymer, the contaminant diffuses within the two layers of polymer with the same constant diffusivity. Convective transfer of the contaminant takes place through the surface of the functional layer in contact with the food, while the other external surface is impermeable to it. The effect of the coefficient of mass transfer at the packaging‐food interface on the rate of transfer of the contaminant to the food is especially studied. Dimensionless numbers are used, making the results general.
Packaging reduction by design
Authors: Eschke K.‐R.
Published: November 2006

German legislation on the avoidance of packaging waste has provoked German industry to reduce packaging in a number of ways. One of these is reducing the sensitivity of engineered products to transport conditions.

The principle of designing such products for the minimisation of their packaging requirements should be supplemented to existing design principles and should be included within the conventional design process.

Thereby, future savings of materials, energy and recycling would be ensured and the competitiveness of industry would be increased as a result of cost reductions.
Effect of functional barrier thickness for a food package with recycled polymer
Authors: Laoubi S. , Feigenbaum A. , Vergnaud J. M.
Published: November 2006

Food packaging films can be made of bilayer polymers, one being a virgin polymer and the other the recycled polymer. The mathematical treatment of the diffusion of a contaminant with constant diffusivity when the two polymers are of the same nature is considered. Moreover it is considered that the contaminant does not pass through the external surfaces of the packaging. The effect of the relative thicknesses of the virgin and recycled polymers is presented using dimensionless numbers so as to establish general results. Master curves of the profiles of concentration of contaminant developed through the packaging are drawn as are the kinetics of contaminant transfer into the virgin polymer and the increase in its concentration at the external surface of the virgin polymer. From the master curves thus obtained it is possible to determine in any typical case the time necessary for a given transport of pollutant to occur.
A mathematical model for the migration of naphthalene from the atmosphere into milk drink packaged in polyethylene bottles
Authors: Lau Oi‐Wah , Wong Siu‐Kay , Leung Ka‐Sing
Published: November 2006

A model was established to relate the amount of naphthalene migrating from the surrounding air into milk contained in LDPE bottles after exposure to an environment having a considerable amount of naphthalene. Although the real situation is very complicated, the model was established by treating the case as involving migration into milk from a time‐dependent source of naphthalene, the equation for which is based on the increase with time in the naphthalene concentration in the LDPE bottles in the same environment. A model was then suggested to relate the amount of naphthalene migrating into milk with time as well as the naphthalene concentration in the surrounding air. Finally, the validity of the established model was checked for milk drinks exposed during storage to a naphthalene‐based moth repellent stored in a confined space.
Study of water migration kinetics from a simulated high moisture food into packaging material by means of NIR reflection spectroscopy
Authors: Bizet C. , Desobry S. , Hardy J.
Published: November 2006

Moisture loss from high moisture foods to air through their packaging is economically very important. The knowledge of paper behaviour towards water is then useful to improve the storage of packaged food. It also permits an understanding of water transport phenomena in paper. We studied the water absorption profiles of seven different papers, from agar gel (simulating cheese) to ambient air. These absorptions were followed by near infra‐red (NIR) spectroscopy. Maximum water absorption capacities were compared with those obtained by a standardised but static method (COBB test) and related to a structural parameter, ‐porosity. Absorption speeds were also related to porosity and showed the influence of porosity on the predominance of capillarity or diffusion in the transport of water in paper.
Application of active film packaging to transport live fish
Authors: Yongxin Li , Hui Li
Published: November 2006

Cylindrical bags made of inorganic‐filled PE film (active film) (AF) containing fresh water were applied to storage of living carp. The tops of the bags were usually kept closed, with the exception of the moment for determining the content of dissolved oxygen (DO). For comparison, a cylindrical glass jar and other cylindrical bags made of plain PE film were used for the same test. The results show that the mean life of carp in the AF bag was more than 64h, whereas those in the glass jar and the plain PE film bags were 25 and 26h, respectively. The content of DO in the different types of container with living carp was measured. It indicated that the content of DO in the AF bags was more than that in the others. Thus, it is significant that it can be used to store and transport aquatic plant and animal or other organisms in a closed container.
Some of the Minor Constituents of Wheat Starch and its Hydrolysates ‐ Part 1.‐
Authors: Cornell H. J.
Published: November 2006

The application of sedimentation analysis to the calculation of specific surface area of various wheat starch fractions in conjunction with determination of lipid content indicated that much of the lipid is contained in the outer layer of the starch granule.

In order to rupture the lipid‐rich layer of the starch, it was necessary to heat the starch for long periods in 0.1 M sodium hydroxide at a temperature of 42°C. Nitrogen contents were reduced from 0.044% to less than 0.014% and reduction of the lipid content in a similar ratio was also achieved.

In ordinary refined starch fractions, ratios of the nitrogen content to lipid content were reasonably constant, similar to those obtained on the lipid separated from acid hydrolysates of 42 D. E. which suggests a close association between lipid and nitrogen. Crude starches, which had a greater proportion of their nitrogen in the form of gluten and pentosan proteins gave higher nitrogen to lipid ratios than the refined starch.

An approximately linear relationship between the percentage of nitrogen in the separated lipid and the D. E. of the hydrolysate was found to hold in the range 30–70 D. E. If it could be assumed that the same relationship held below 30 D. E., extrapolation to zero D. E., indicated a nitrogen content of 3.1% in the lipid of the starch. This takes into account practically all of the nitrogen of a refined wheat starch.

In order to limit the amount of lipid present in wheat starch hydrolysates and thereby reduce the number of problems encountered in processing wheat starch into refined syrups, the fine granules should be removed efficiently. This would reduce the extent of foaming when hydrolysates are partially neutralised, and improve the efficiency of the filtering operation.
Photometrische Titration der Särkepolysaccharide mit Jod. II. Mitt. Hydrolyse mechano‐chemisch abgebauter Amylose durch β‐Amylase
Authors: Richter M.
Published: November 2006

Photometric Titration of Starch Polysaccharides by Iodine. Part 2: Hydrolysis of Mechano Chemically Degraded Amylose by β‐Amylase. With photometric titration of amylose by means of iodine, the course of the graph depends on molecular weight distribution, average molecular size and concentration of polysaccharides. Respective data are: size of the linear part of the titration graph, total iodine concentration at half saturation of amylose by iodine, and maximum value of extinction. This new method is applied to examine β‐amylolysis of natural amylose of various molecular size. High‐molecular substrates are degraded according to a single‐chain mechanism and amyloses having been swing‐milled for more than 48 h are degraded by a multichain mechanism. The change in the effect of β‐amylase occurs in the range between Pn 130 and 200, This change is to be contributed to differences in the molecular configuration of the substrate.
Zur genaueren Kenntnis durch Temperatureinfluß modifizierter Wachsmais‐ und Amylosestärke
Authors: Blinc M. , Cimerman A. , Pertot E. , Stucin D.
Published: November 2006

Contribution on Waxy Maize Starch and High Amylose Starch Modified under the Influence of Temperature. The starches of the two genetic varieties of the corn grain, waxy maize starch and high amylose starch, were subjected to the influence of different temperatures. Subsequently, the physico‐chemical properties of the modified starches were examined. Waxy maize starch which mainly consists of amylopectin, and high amylose starch which contains a high portion of linear chains of polymerized glucose units are interesting test materials because of their properties which are different by nature.

Waxy maize starch with its high viscosity values, great swelling power and good solubility in hot water shows no tendency to settle or retrograde. While the process of freezing the starch granules hardly changes the properties mentioned, the influence of a temperature of 100°C causes morphological changes of a small proportion of grains, including the loss of birefringence. These changes are particularly pronounced after treatment of native starch at 120°C. The properties of the starch pastes were also strongly changed.

The native high amylose starch characterized by unusual, oblong starch granules without birefringence, a low viscosity, low swelling power and low solubility showed only minor changes after freezing, whereas a temperature of 100°C resulted in reduced values of solubility and aggregation of the starch granules. A temperature treatment at 120°C and at 125°C brought about changes in the swelling properties, the viscosity and limiting viscosity, settling, swelling power, and solubility of the starch pastes.

Attempts were made to conform the changes in the different properties observed with the expected influence of temperature treatment on the intermolecular forces (hydrogen bonds, crossbonding).
Analyse und Charakterisierung von Glucosesirup mit Hilfe der Gelchromatographie
Authors: Trénel G. , Emeis C. C.
Published: November 2006

Analysis and Characterization of Glucose Sirup by Means of Gel Chromatography. A series of glucose sirups have been investigated by gel chromatography technique with respect to their carbohydrate composition. It was possible to determine both qualitatively and quantitatively the carbohydrate components from 1 up to 15 glucose units. Several sirups which have been manufactured by acid, acid‐enzyme and enzyme‐enzyme hydrolysis have been analyzed. Characteristic differences occurred in dependence to the manufacturing techniques.
Die Verteilung von Stärke und Amyloseanteilen in der Kartoffelknolle
Authors: Mič B.
Published: November 2006

Distribution of Starch and Amylose Components in the Potato Tuber. Distribution of dry matter and starch in potato tubers has been studied. Moreover, distribution of amylose components of the starch and qualitative properties of the isolated starch as well as the interrelation between the received data have been examined.

From the results it is seen that with most varieties a tendency towards an increase of the dry matter content at the navel end is perceptible. This tendency is more distinct with big tubers. On an average, the starch content was higher at the navel end than at the crown end of the tuber with almost all samples.

Starch from big tubers shows a higher viscosity than that obtained from small tubers. Viscosity of the starch from the navel end of small tubers is lower than that from the crown end; with big tubers this is the other way round.

Amylose content of starch from small tubers is lower than that from big tubers. Starch, which had been isolated from the crown end of small tubers contained mainly a lower amylose content than the starch isolated from the navel end. Again the situation was the other way round with big tubers.

Quality of starch is furthermore also determined by the size of the starch granules. With big tubers a higher amount of bigger granules is to be found. This must be contributed to the fact that in big tubers a higher stage of maturity is reached.

Another factor that has been very rarely examined so far is the steeping temperature of starch granules. Apparently the vegetation year has its influence on this factor, too. Differences between the two parts of the tuber were insignificant with small tubers. With big tubers the average steeping temperature of granules was higher in the navel end than in the crown end. The whole complex has been examined from the point of view that the origin of the starch does not have a great significance, although here an interrelation might have been expected. The following relations have been stated by means of the correlation coefficient: amylose content, viscosity, granules (21–40 μm), granules (41–70 μm), average granule size. From the results it is clear that the correlation coefficient between starch content and the amylose content is negative. The correlation between granules of the second (21–40 μm) and the third (41–70 μm) category also proved to be negative.

From the basis of the correlation coefficients a regression equation for the statistically secured results may be calculated.
Neue Erfahrungen bei der Herstellung von Stärkeverzuckerungsprodukten aus Maisgrits
Authors: van Twisk P.
Published: November 2006

New Concepts on the Production of Hydrolyzed Starch Products from Maize Grits.

The application of a Brabender amylograph for investigating different methods of pre‐treating maize grits prior to enzymatic liquefaction with α‐amylase is described. The effect of pretreatment on grain structure is illustrated with microscopic photographs. The possibility of amylase inhibitors obstructing liquefaction is subsequently discussed. The application of a Votator continuous cooker for affecting liquefaction while at the same time eliminating pre‐treatment is illustrated. The advantages of such a continuous cooking procedure is finally described.
Infrared Spectra of Nitrated Polymeric Carbohydrates
Authors: Asker Wafia , Dawoud Abdel Fattah , Marawan Ashraf
Published: November 2006

Nitrated Polymeric carbohydrates are not very pure when used, as their physical constants are neither sharp nor unique for positive identification purposes. The ingredients of explosives are so numerous and it was considered beyond the scope of this investigation to include them.
Biochemisch‐technologische Studienüber die Naßverarbeitung von Mais 4. Mitteilung. Über die qualitative Zusammensetzung des Mais‐Hydrolasensystems und Aktivität einzelner Enzyme bzw. Enzymgruppen
Authors: Wahl G.
Published: November 2006

Biochemical‐technological Studies on Wet‐Processing of Maize. Part 4. On the Qualitative Composition of the Maize Hydrolase System and the Activity of Particular Enzymes Respectively Enzyme Groups.

Enzyme preparations have been isolated from the maize meal by means of water extraction and following protein precipitation (ethanol, ammonium sulphate, acetone). Cleaning or concentration operations have been left out, in order to preserve the enzyme system of the maize in its totality

By paper chromatographical studies on these preparations as well as special activity deter minations a‐ and β‐ amylase could be traced in the ungerminated as well as in the germinated maize and the presence of phosphorylase could be confirmed. For enzymatic handling of the non‐gelatinized starch a‐ amylase is above all convenient, but slight degradation by β‐amylase cannot be overlooked.

By means of paper chromatography and reductometry β‐fructofuranosidase, a‐glucosidase, β‐glucosidase could be clearly traced in the germinated and ungerminated maize. a‐Galactosidase could be traced with some reservation. Matters in this group have in common the faculty for hydrolysis and synthesis of glucosidic bondings. Proteinase and lipase have been traced in all preparations, peptidase exclusively in those from germinated maize and their activities have been determined.

Of all the maize sorts examined, hard maize shows higher activities with all enzyme species compared to dent maize.
Contribution a l'étude de l'action du rayonnement sur l'amidon Partie 1. Évolution de certaines caracteristique physico‐chimiques du grain d'amidon en fonction des conditions d'irradiation.
Authors: Th. Tollier Par M. , Guilbot A.
Published: November 2006

The Development of Certain Physico‐Chemical Properties of the Starch Granule as a Function of Irradiation Conditions.

Maize and potato starch of different water content have been exposed to γ‐irradiation, and the development of certain properties of the starch granules has been followed. These properties have been judged by evaluating the picture in the optical microscope, solubility in alcohol at 80° GL and water at 20 °C, as well as swelling and solubility in aqueous medium dependent on temperature.

Examinations have been carried out both in dependence of irradiation dosis with constant water content and in dependence of water content with constant irradiation dosis of 25 Mr.

Results obtained make it possible to follow the degradation of starch macromolecules under the influence of irradiation, and at the same time show the protecting effect of water within the sample, especially with lower irradiation doses. The change in the swelling faculty and solubility of starch at different temperatures clearly show the important role which the intermolecular associations play in this connection.
Das Altbackenwerden des Brotes und die Erhaltung seines Frischzustandes
Authors: Knjaginičev M. I.
Published: November 2006

The Staling of Bread and the Maintainance of its Freshness.

In this survey the processes occurring in the course of the staling of wheat bread and rye bread are extensively examined. Especially the physico‐chemical changes in the starch as well as its interaction with the other constituents of the bread, above all gluten and water are discussed. Apart from literature data results of works of the author and his associates are discussed with special reference to experiments with pure starch.

The starch is the principal origin for the staling of bread. With storing the macromolecules of the starch as well as the water molecules lose their mobility between about + 50 °C and –7°C forming a structured system which leads to the staling of bread.

With storing of white bread with little in‐baked starch sacks it was shown that the water content of the starch decreased despite the higher water content of the crumb at a similar rate, i. e. from 31.3% (after 4 hrs) to 28.9% (after 8 days) in the starch, and from 42.2% to 39.0% in the crumb. Thus no considerable redistribution of water from the well‐watered crumb to the more arid starch takes place.

The author suggests a model, according to which the pore walls of the crumb consisting of starch and denaturized proteins represents a swelled system in which part of the water is thermodynamically bound and partly distributed in the intermolecular spaces of protein and the swollen partially gelatinized starch. Here the molecules of water, starch and protein form a uniform structure system. During refreshening of staled bread by heating the structure of water in the micropores of the crumb is disturbed. Thus, the macromolecules of starch and protein can return to that state which is characteristic for fresh bread.
Lablab Bean Starch. I. Properties of its Granules and Pastes
Authors: Rosenthal F. R. T. , Espindola L. , Serapião M. I. S. , Silva S. M. O.
Published: November 2006

The variety of lablab bean (Dolichos lablab) starch studied by the authors, presents smaller‐sized, rounded granules, and others, larger ones, which are generally oval‐shaped and measure up to 30 micra. These latter show 1, 2 or 3 polarization crosses under polarized light. The gelatinization temperature of the granules varies between 65–70–76 °C and iodine affinity shows a value of 6.05.

Graphs were drawn for the swelling power, percentage of solubles, Brabender viscosity of the hot and cold pastes, and also for the observation of the effect of a‐amylase on these pastes.

It was observed that the starch pastes present the cross‐linked type Brabender viscosity curves, which greatly resemble those of the chick pea, yellow pea and navy bean starches. Several theories relating to the composition and structure of the starch, and which might explain its behavior, were approached by the authors.
Aspects of Retrogradation in Some Dehydrated Starch‐Containing Precooked Food Products
Authors: Hellendoorn E. W.
Published: November 2006

Retrogradation has a positive influence on mouth appeal of rehydrated mashed potato products, and a negative effect on the consistency of dried pulses. The texture of rehydrated precooked rice can be improved by retrogradation.
A New Formula for the Description of the Conformation of Pyranoid Sugars
Authors: Szejtli J.
Published: November 2006

Reeves' conformational formulas of aldopyranoses can be described by combinations of letters and numbers. This system may be especially useful when many conformational formulas would have to be printed. The C1 conformation of sugars in the D‐series is to be visualized with the C1 atom on the right, below, and the C4 atom on the left, above in the chair form = 4C1, and the ring members must be numbered clockwise. Applying these conventions, both in the D‐ and L‐series the axial substituents attached to the C1, C3 and C5 atoms in the C1 conformation are directed downwards, while those affixed to the C2 and C4 atoms point upwards relative to the plane of the ring. The C5‐substituent in pyranoses of C1 conformation is axial in the case of L‐sugars, and equatorial in D‐sugars. The axial position is designated in the formula by its location written in parentheses and the substituents other than ‐H and ‐OH are indicated behind the parentheses. 4C1 means an aldopyranose ring of C1 conformation. 4C1(‐)5‐CH2OH means β‐D‐glucopyranose, 4C1(1,2)5‐CH2OH denotes α‐D‐mannopyranose. If the figure “5” also occurs in parentheses, the symbol represents an L‐sugar, e.g., 4C1(1,2,5)5‐CH2OH means β‐L‐gulose, or 4C1(1,2,5)5‐COOH,3‐deoxy is 3‐deoxy‐β‐L‐guluronic acid in C1 conformation. The 1C conformation is designated as 1C4, B1 as 4B1, B2 as 5B2, etc. The ring members are numbered in the “alternative” conformations (1C, 1B, 2B, 3B) counter‐clockwise.
Einfluß einer mechanischen Bewegung des Maises während des Quellprozesses auf die Ausbeuten
Authors: Kempf W.
Published: November 2006

The Influence on the Yields by Mechanical Movement of Corn during the Steeping Process. Using two different corn varieties, U. S. Yellow Corn No. 2 and Kenya White Maize, it was tried to find out — in comparison with the conventional corn steeping process, wether higher starch yields may be obtained by means of mechanical movement of corn during the steeping process with steeping time remaining unchanged, or if equal starch yields may be obtained at as shortened steeping time. Naturally, this requires at least equal quality properties of the obtained starches. Under this premise, respective conclusions have been drawn from the results of laboratory yield determinations and analytical tests. In connection with earlier results several criteria for further possibilities of development in the field are given.
Air‐Oxidation of Starch Using Quinquevalent Vanadium as Catalyst
Authors: Harmon R. E. , Gupta S. K. , Johnson J.
Published: November 2006

Air‐oxidation of corn starch in the presence of ammonium meta vanadate at 35–40°C and pH 9 has been studied. The resulting oxidized starch contained more carbonyl but less carboxyl as compared to an industrial oxidized starch. However, the presence of undesirable amounts of the catalyst imparted extremely high viscosity to the oxidized starch.

The ultraviolet irradiation was found to have a pronounced effect on the air oxidation of starch in the presence of ammonium meta vanadate. Increased carboxyl content was observed in the UV light catalyzed oxidized starch.
Biochemisch‐technologische Studien über die Naßverarbeitung von Mais. 6. Mitteilung. Untersuchung des proteolytischen und lipolytischen Enzymsystems des Maises
Authors: Wahl G.
Published: November 2006

Biochemical‐Technological Studies on Wet‐Processing of Maize. Part 6. Examination of the Proteolytic and the Lipolytic Enzyme System of Maize.

1. Maize lipase shows the following optima: pH‐optimum about 8,0, temperature optimum about 40°C.

2. The efficiency of the proteolytic enzymes covers a broad pH‐range (2,0–9,0). Efficiency reaches a distinct maximum between pH 3,5 and 4,5 and a weaker maximum at pH 8. Enzymes show high stability (45 °C). For proteolysis of the maize protein temperatures around 40 °C are the optimum.

3. Maize proteases are inactivated by 2 · 10−3 M potassium persulfate and 6 · 10−4 M potassium bromate; 6,5 · 10−3 M cysteine doubles activity.

4. SO2‐contents up to 0,1% cause an increase of proteolytic degradation with a maximum at 0,03%.
Properties of Cyclodextrins. Part VI. Water‐Soluble Cyclodextrin‐Derivatives. Preparation and Analysis
Authors: Lammers J. N. J. J. , Koole J. L. , Hurkmans J.
Published: November 2006

Inclusion compounds with cyclodextrins in aqueous solution are only known in case the included compound is a polar substance; with apolar substances only very slightly soluble inclusion compounds are formed.

In order to be able to make inclusion compounds with apolar substances in solution, hydrophylic cyclodextrin derivatives have been prepared, viz. the carboxymethylether Na‐salt, the sulfopropylether Na‐salt and a soluble epichlorohydrin resin of both a and ß cyclodextrin. The molecular weight (apparent void concentration, respectively) of the derivatives is determined in a number of different ways.
Effect on the Gelatinization Temperature of Wheat Starch Granules of Prolonged Treatment with Water at 50°C
Authors: Gough B. M. , Pybus J. N.
Published: November 2006

Undamaged wheat starch granules were treated in water at 50°C for 72 hours, and their properties then compared with those of the parent starch before and after gelatinization. Some of their attributes suggest that little alteration has occurred, but changes in others indicate that the internal structure of the granule has been modified, increasing its heterogeneity in some respects, but reducing it in others. In particular, gelatinization occurs at a higher but much more sharply defined temperature as compared with the range of temperatures shown by the mixture of untreated granules.
Studies on Carbohydrate Metabolising Enzymes. Part XXVI. The Limit Dextrinase from Germinated Barley
Authors: Manners D. J. , Yellowlees D.
Published: November 2006

Limit dextrinase was isolated from an extract of freshly germinated barley by precipitation with ammonium sulphate followed by continuous electrophoresis. Enzyme activity was assayed using pullulan as substrate. The purified enzyme can release α‐(1→6)‐linked maltosyl and maltotriosyl units from both oligosaccharide and polysaccharide substrates (e.g. amylopectin β‐limit dextrin). It had no action on substrates containing α(1→6)‐linked glucosyl residues, or on amylopectin, glycogen, or glycogen β‐limit dextrin. The enzyme also synthesised branched oligosaccharides from maltose and various maltosaccharides; glucose was not a substrate for these condensation reactions.
Étude, par diffraction des rayons X, de I'influence de la cryodessiccation sur la structure cristalline de I'amidon
Authors: Robin Par J. P. , Duprat F. , Charbonnière R. , Guitbot A.
Published: November 2006

Examination on the Influence of Freeze‐Drying on Crystalline Starch Structure by Means of X‐Ray Diffractometry.

The influence of freeze‐drying on the crystalline structure of various starches (potato, wheat, maize, waxy maize, manioca, arrow‐root) and wheat amylose has been examined by means of X‐ray diffractometric diagrams. Only the crystalline structure of potato starch is altered by the treatment. A change in structure becomes apparent only, if freeze‐drying is done slowly and if the water content of starch is above 25%, related to d. s. However, a restoration of the original structure of starch is possible, by moistening under certain conditions as described in the text.

An explanation for the observations is proposed by means of a new hypothesis on structure organization of starch granules as well as the part of water as a determining factor for organization.
Starch in Rubber Influence of Starch Type and Concomitant Variables in Reinforcement of Styrene‐Butadiene Rubbers
Authors: Buchanan R. A. , Kwolek W. F. , Katz H. C. , Russell C. R.
Published: November 2006

These studies allowed selection of four starch derivative styrene butadiene elastomer (SBR) masterbatch compositions for future optimization studies. The main factor remaining to be optimized is level of resorcinol‐formaldehyde (RF) incorporation; but fine adjustment of such factors as starch loading and plasticizer incorporation is needed also.

Results in these experiments suggest that further study of certain high‐amylose starch compositions might lead to masterbatches giving vulcanizates with both low water adsorption and good strength properties. Further work is also needed on oil‐extension of starch derivative‐SBR masterbatches.

Properties of selected starch‐SBR masterbatches met requirements of the rubber industry for many end‐use applications.
La caractérisation des amidons eu égard à leurs utilisations industrielles en particulier dans l'industrie textile et papetière
Authors: Schutz Par R. A.
Published: November 2006

Characterization of Starches with Respect to their Application in the Industry, especially in the Textile and the Paper Industry.

After a short review of the economical importance of starch in the textile and the paper sector the author shows how he characterizes the industrial starches: water content (after the French Standard AFNOR V. 03602), microscopic examination (normal and polarized light, phase contraste, 100 × or 250 × magnification), nitrogen content (Kjeldahl), ash content (AFNOR V. 03605), color, pH‐value of water extract, and particulary rheological behaviour. At this point the following is accentued:

Starch/water systems are not true Newtonian. They have not one viscosity alone but an infinity of apparent viscosities in relation with the rheological conditions. To give one value even in arbitrary units without precise informations about shear rate and shear stress is meaningless.

The preparation of the starch paste is a multiphenomene and needs a non‐laminar stirring. That means that it is illusive to obtain reproducible torque value by rotation at constant speed from one apparatus to another.

Only rheometers with coaxial cylinder permit an absolute characterization of the before prepared starch/water system.
Pollen Starch from Amylomaize
Authors: Banks W. , Greenwood C. T. , Muir D. D. , Walker J. T.
Published: November 2006

Starch has been extracted from the pollen of band 5 and band 7 amylomaizes which are homozygous for the amylose extender (ae) gene. Microscopic examination showed the starch granules to be small, prolate ellipsoids, having minor diameters of approximately 0.5 μ and major diameters of 1–2 μ. Potentiometric iodine titration of the starches showed the apparent amylose content to be high, and to be grossly dependent on the temperature of measurement. This behavioural pattern is similar to that observed for the endosperm starches of amylomaize. It is therefore concluded that the starches of the gametophytic and sporophytic generations of amylomaize are similar in type.
Katalytische Nachverbrennung von Abluft aus Trocknern der Maisstärkeindustrie
Authors: Hoepke C.‐H.
Published: November 2006

Catalytic Delayed Combustion of Affluent Air from Dryers of Corn Starch Industry.

In connection with anti‐pollution measures, it had in the past been nearly unfeasible technically and unacceptable economically to achieve effecient deodorization with steam saturated vapours originating from dryers in which organic substances are dried (in this case feed). Following comprehensive preliminary trials, a large‐scale pilot plant for catalytic final combustion of dryer vapours was built in cooperation with the competent district and state government authorities and in collaboration with the Instiute for immission and soil exploitation protection. The exhaust air, which has a temperature of approx. 80°C, is heated to 440°C by means of natural gas and is passed via a platinum catalyst. The odor carriers which are of organochemical nature are burnt to carbon dioxide and water. The hot odor‐free gases are then either exhausted into the open air or used dry other products, in this case corn protein (gluten).

Analyses established that the plant operated with a conversion of more than 95%. Operating costs are considerable but still acceptable from an economic point of view when the hot exhaust gas is utilized.
Borate Ion ‐ Carbohydrate Complexes as Determined by Gas Liquid Chromatography
Authors: Jacin H. , Chester Port
Published: November 2006

The experimental data shows that the carbohydrate — borate complexes can be investigated by gas liquid chromatography. One of the advantages of this procedure is the possibility of observing the behavior of the α and β anomers in the presence of borate, a possibility unavailable when electrophoretic, conductometric or pH changes are used in the study of borate carbohydrate complexes.