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The effect of variety and environment factors on physico-chemical properties of potato starch

100%

Kolodziej Z.

Polish Journal of Food and Nutrition Sciences

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1993

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tom 02

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nr 2

2

Small angle X-ray scattering [SAXS] investigations on potato starch in suspensions

100%

Pikus S., Jamroz J., Kobylas E.

Żywność Nauka Technologia Jakość. Suplement

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2000

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tom 07

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nr 2

Small angle X-ray scattering (SAXS) is one of the methods used for the analysis of the starch structure. In this manner, involving changes in electron density structure of starch becomes available. By variation of the media in which starch is suspended wider differentiation of starch structure is possible. Usually such studies are carried out in water. In this paper the SAXS method was successfully used for investigation of starch structure in such media as water, methanol, 1 M solution of HCl, 1 M solution of NaCl, and 0.1 M solution of I2 in KI. Analysis of SAXS curves for those suspensions proved some differences in curve pattern. Especially interesting data were obtained from a comparison of SAXS curves for starch suspensions in 1 M HCl and 1 M NaCl. Effective scattering of starch suspension in 1 M HCl in the initial part of the curve, as compared to the 1 M NaCl case, indicates that the diffusion of СГ ions to various regions of the starch structures depends, among other things, on the pH of the solution. These results demonstrated that the SAXS method could be used for identification of the starch structures to which specific media diffuse and, therefore, for investigating the impact of various factors on this diffusion.

3

Properties of cation-saturated starch subjected to extrusion

88%

Golachowski A., Brzeski P.

Polish Journal of Food and Nutrition Sciences

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2001

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tom 10

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nr 3

The properties oť potato starch saturated with Na, K, Ca and H cations were studied in extrudates cooked at 60°-65°-75°C, 90°-105°-120°C and 140°-155°-170°C. The morphological features of the extrudates, their specific gravity and expansion ratio as well as starch properties depended on the temperature of extrusion and type of saturating cations. The higher were the temperatures of extrusion, the higher was the solubility of the extrudates, but lower rétrogradation degree and the amount of sediment obtained from centrifuged pastes. The starches saturated with Na, K, Ca and H cations, either non-extruded or extruded at 60°-65°-75°C and 90°-105o-120°C exhibited different solubility and rétrogradation degree; the starches extruded at 140°-155o-170°C were totally soluble and their rétrogradation degree was similar. Some differences in water absorption capacity of the extruded starches saturated with different cations were observed - the extrudates of Na, K and Ca starches exhibited higher water absorption capacity than non-extruded starches, while the water absorption capacity of extruded hydrogen starch was lower than before extrusion.

4

Influence of starch content on selected properties of hardboard

75%

Wronka A., Rdest A., Kowaluk G.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

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2020

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tom 109

5

Zmiany wlasciwosci fizykochemicznych skrobi ziemniaczanej wywolane procesem utleniania

75%

Pietrzyk S., Fortuna T.

Zeszyty Problemowe Postępów Nauk Rolniczych

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2006

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tom 511

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nr 2

627-637

Native potato starch was oxidized by means of: sodium chlorate(I), hydrogen peroxide and sodium chlorate(III) - at presence of formaldehyde. Native and modified starches were analyzed for the contents of carboxylic and aldehyde groups, amylose and total phosphorus. Also water binding capacity as well as the solubility in water, gelatinization characteristics and flowing curves analyses were done. On the bases of obtained results it may be stated that sodium chlorate(I) and hydrogen peroxide were more effective oxidizing agents than sodium chlorate(III). Oxidized starches were characterized by lower total phosphorus and amylose contents. All applied modifications caused total solubility of obtained starches at 80°C. Modification with sodium chlorate(III) and hydrogen peroxide did not change the water biding capacity of starch solubility in water at temp. 60°C, whereas with the sodium chlorate(III) - the solubility only. It was also observed, the lowering of parameters of gelatinization profile and K coefficient of consistency due to action of oxidizing agents. Sodium chlorate(III) decreased the viscosity of obtained glued starch only during refrigeration and holding at temperature 50°C.

6

Encapsulation of gallic acid with acid-modified low dextrose equivalent potato starch using spray- and freeze-drying techniques

75%

Sepelevs I., Stepanova V., Galoburda R.

Polish Journal of Food and Nutrition Sciences

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2018

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tom 68

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nr 3

The main objective of the present study was to investigate the effect of spray- and freeze-drying techniques on the microencapsulation of a gallic acid compound using the acid-hydrolyzed low dextrose equivalent potato starch as a wall material. During the experiment, it was possible to achieve encapsulation efficiency of 70–84% for the freeze-dried and 65–79% for spray-dried samples, without statistically signifi cant difference (P>0.05) in the encapsulation efficiency between the mentioned methods. Spray-dried samples formed spherical capsules with a higher number of micropores. Meanwhile, freeze-dried samples were shapeless, exposed larger pore volume (from 2.4×10–3 to 9.5×10–3 cm3 /g against 1.2×10–3 4.9×10–3 cm3 /g; analyzed by Barrett-Joyner-Halenda method) and overall higher surface area (0.632–1.225 m²/g against 0.472–1.296 m²/g; analyzed by Barrett-Joyner- -Halenda method). Due to this fact, more gallic acid molecules were exposed to environmental factors and can be counted as losses. In addition, freeze-dried samples demonstrated lower water activity than spray-dried samples (0.075±0.014 against 0.178±0.008). Results showed that it is not practical to use freeze-drying for modelling encapsulation for food industry without a special necessity for protection of easily degradable chemical compounds. The present work makes a basis for the future studies of the microencapsulated phenolics application in food production.

7

Influence of glycerol and temperature on the rheological properties of potato starch solutions

75%

Ayala G., Vargas R. A., Agudelo A. C.

International Agrophysics

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2014

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tom 28

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nr 3

Effects of temperature and glycerol concentration on rheological properties of potato starch solutions were investi- gated. The flow behaviour (shear stress against shear rate) was fitted to various models: power law, Herschel-Bulkley, Bingham, modified Bingham and Casson models. However, it was found that the Herschel-Bulkley model describes better the flow behaviour observed at various temperatures and glycerol concentrations, for flow behaviour index values between 0.44 and 0.78, typical of pseudoplastic solutions. The effect of glycerol concentration on each of the fitting parameters for Herschel-Bulkley model was well modelled by a second-degree polynomial at various temperatures. The simultaneous influence of glycerol concentration and tempe- rature on shear stress could be represented empirically by a second- degree polynomial function that includes linear coupling between concentration and temperature. Finally, the variation of the con- sistency coefficient with both temperature and glycerol concentra- tion was well described by an exponential expression, with an acti- vation energy value of 2.78 kJ mol -1 . The results indicate that both glycerol content and temperature have the effect of diluting potato starch solutions.

8

Effect of natural fibres on the mechanical properties of thermoplastic starch

75%

Oniszczuk T., Wojtowicz A., Moscicki L., Mitrus M., Kupryaniuk K., Kusz A., Bartnik G.

International Agrophysics

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2016

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tom 30

|

nr 2

9

Mechanical properties of potato starch modified by moisture content and addition of lubricant

75%

Stasiak M., Molenda M., Horabik J., Mueller P., Opalinski I.

International Agrophysics

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2014

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tom 28

|

nr 4

Laboratory testing was conducted to deliver a set of characteristics of structure and mechanical properties of pure starch and starch with an addition of a lubricant – magnesium stearate. Considerable influence of moisture content of potato starch was found in the case of density, parameters of internal friction, coefficients of wall friction and flowability. Elasticity was found to be strongly influenced by water content of the material. Addition of magnesium stearate affected density and parameters of flowability, internal friction and elasticity. Bulk density increased from 604 to 774 kg m-3 with decrease in moisture content of potato starch from 17 to for 6%. Addition of magnesium stearate resulted in approximately 10% decrease in bulk density. Angle of internal friction obtained for 10 kPa of consolidation stress decreased from 33 to 24º with increase in moisture content, and to approxi- mately 22º with addition of the lubricant. With an increase of moisture content from 6 to 18% and with addition of the lubricant, the modulus of elasticity during loading decreased from approximately 1.0 to 0.1 MPa. Modulus of elasticity during un- loading was found in the range from 19 to 42 MPa and increased with increase of moisture content and amount of lubricant.

10

Rheological properties of potato starch pastes with the addition of kaolin

75%

Drozdz W., Tomaszewska-Ciosk E.

Polish Journal of Food and Nutrition Sciences

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2007

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tom 57

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nr 4[A]

113-117

A study was undertaken to investigate rheological properties of pastes (20 g/L of starch) supplemented with kaolin at doses of 20 g/L, 40 g/L and 60 g/L, stored for various periods of time. Flow curves were plotted at a time span of 200 s, a shear rate of 0-100 s-1 and a temperature of 20°C. The flow curves were described by means of Ostwald de Waele’s and Casson’s models. It was demonstrated that starch pastes with different addition of kaolin stored for various periods of time displayed characteristics of non-Newtonian, pseudoplastic shear-thinned fluids and that their rheological properties depended on both kaolin addition and time of storage. The pastes prepared with the addition of kaolin were characterised by higher viscosity, higher values of shearing stresses, coefficient of consistency K, plastic viscosity ηC and yield point τoC as compared to those prepared only from starch. Values of those parameters were observed to increase along with storage time in samples with the addition of kaolin, and to decrease in the case of pastes prepared only from starch.

11

Porosity of starch granules of different origin

75%

Juszczak L., Fortuna T., Wodnicka K.

Polish Journal of Food and Nutrition Sciences

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2002

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tom 11/52

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nr 2

The helium, apparent, and bulk densities were determined for ten types of starch. On the hasis of the results obtained, the porosity and volume of opened pores in starch granules and starch beds were calculated. The highest values for porosity and total volume of opened pores were characteristic of oat and tapioca starches, whereas triticale, rye and potato starches had these values the lowest. In the case of wheat and potato starches, the porosity of the closed type was shown.

12

Effect of acetylation on microstructure of potato starch

75%

Lewandowicz G., Blaszczak W., Fornal J.

Polish Journal of Food and Nutrition Sciences

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1998

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tom 07

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nr 2 Suppl.

13

Application of experimental design method in floacculants production process

75%

Zielinski R.

Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze

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2007

|

nr 1

14

Thermal transition characteristics and gel properties of heat-moisture treated corn and potato starches

75%

Chung H. J., Chang E. H., Lim S. T.

Żywność Nauka Technologia Jakość. Suplement

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2000

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tom 07

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nr 2

Normal corn starch containing 25 or 30% moisture and potato starch containing 20 or 25% moisture were heat-moisture treated at 120°C for 1 h and the changes in thermal transition characteristics and gel properties of the starches were examined. Granular crystallinity on X-ray diffractogram, especially for potato starch, was reduced by the heat-moisture treatment (HMT). At a limited moisture content (15% based on total weight), Tg measured in granular form of starch decreased by 2-6°C. At Tg, the change in heat capacity (∆CP) of the treated starch was substantially higher than of the corresponding native starch. Crystal melting of the heat-moisture treated starches, measured at 80% moisture, appeared to be biphasic on a DSC thermogram, in that the original endotherm became smaller while a new endotherm at higher temperature was enlarged by the HMT. However, the total melting enthalpy for starch decreased, indicating a partial loss of crystallinity. The degree of rétrogradation under DSC was not significantly different between the native and treated starches. The HMT starches formed the gel with more opaqueness and brittleness. The gel stability from freeze-thawing treatment was slightly increased with corn starch, but decreased with potato by the HMT. Overall results on the paste viscosity and gel properties indicated that the HMT provided physical cross-linking effects on starch.

15

Acid-alcohol degradation of starch

75%

Chang Y., Lin K. S.

Żywność Nauka Technologia Jakość. Suplement

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2002

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tom 09

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nr 4

For revealing the degradation effect of acid-alcohol modification on starch, commercial corn and potato starches were hydrolyzed by 0.36% HCl in methanol at 25°C for 1 to 15 days. Results showed the yields of the modified starches ranged from 91 to 100%, and the average granule size of the modified starch was slightly smaller as compared to their counterpart native starches. After 15 days of modification, no significant configuration change was found whereas the solubility of starches obviously increased with the increase in the hydrolysis time. Corn starch showed a slower increasing tendency than that of potato starch. Gelatinization onset temperatures (To) of starches after modification showed a decrease tendency in corn starch, and an increase tendency in potato starch. For both corn and potato starches, the peak (Tp) and conclusion (Tc) temperatures of gelatinization increased with the increase in the treatment time. Consequently, the range of gelatinization increased from 12.2 to 23.9°C for corn starch, and from 12.8 to 19.8°C for potato starch. However, the gelatinization enthalpies ( • H) of modified starches showed 1 to 2 J/g lower than their counterpart native starches. For the acid-alcohol treated starches, the area of amylopectin fractions determined by high-performance size exclusion chromatography (HPSEC) decreased with the treatment time. Compared to the gradual degradation pattern of corn starch, potato starch showed a stepwise pattern. The weight average degree of polymerization (DPW) of starches rapidly decreased within the first 5 days of treatment, and potato starch had a higher rate of decrease than corn starch. The number average degree of polymerization (DPn) of corn and potato starches after acid-alcohol treated for 15 days were 162 and 183, respectively. It was concluded that the degradation of amylopectin by the acid-alcohol modification might alter the molecular structure of starch, which resulted in the fast disruption of granule and the decrease of viscosity of starch paste during heating.

16

The structure of clusters from potato amylopectin

75%

Bertoft E.

Żywność Nauka Technologia Jakość. Suplement

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2002

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tom 09

|

nr 4

The clusters from size-fractions of hydrolysed amylopectin from amylose-free potato starch (APP) were isolated by controlled α-amylolysis. The external chains were removed by further phosphorolysis and ß-amylolysis, thereby transforming the APP and the clusters into ɸ,ß-limit dextrins. The DP of the ɸ, ß-LD of the clusters was rather uniform around 40-50. The unit chain composition was analysed by HPAEC-PAD and it was shown that the long internal B-chains, that interconnected the clusters in the amylopectin, had preferentially been cut into B-chains with DP 8-23. Smaller clusters possessed also increased amounts of the shortest B-chain with DP 3. The A:B-chain ratio decreased after α-amylolysis, showing that A-chains were not formed. The clusters were built up of only 4-6 chains and the density of branches was 11-13%. Very small, branched building blocks were also isolated from the APP and the clusters by an extensive α-amylolysis and analysed by GPC and HPAEC. The building blocks ranged between DP 5-30 and contained 2-5 very short chains (approx. CL 2-7). The predominating branched building blocks had DP 7-8 and were singly branched. The density of branches within building blocks was high (25%) and the clusters were at average composed of 2 or 3 building blocks.

17

Small granule potato starch, structure and usability

75%

Lewandowicz G., Blaszczak W., Walkowski A.

Żywność Nauka Technologia Jakość. Suplement

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2002

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tom 09

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nr 4

Small granule potato starch (SGPS) produced by "Wielkopolskie Przedsiębiorstwo Przemysłu Ziemniaczanego" during potato starch production season 1999 was investigated to evaluate its physicochemical properties, structure and usability. SPGS was used as a raw material for different modification processes typically applied in the Polish starch industry to obtain both food and non-food products. The obtained preparations were compared with industrial products: food grade modified starches E 1403, E 1404, E 1412, E 1414 and E 1422, as well as two types of preparations for paper industry - oxidised starch for wet end application and corrugated board adhesive. The experimental and reference starch samples were examined by chemical analysis, rheological methods, scanning electron microscopy and X-ray diffractometry. Textural parameters of deserts prepared by means of food grade modified starches as well as some specific functional properties of industrial preparations were investigated. It was found that SPGS like standard potato starch contained quite small amounts of inorganic impurities as well as crude fibre, revealed similar rheological properties but relatively low crystallinity. SGPS due to its unique physicochemical properties could be recommend as a raw material for the production of corrugated board adhesive. Reactivity of SGPS towards sodium hypochlorite was found lower as compare to standard one. On the contrary susceptibility of SGPS to crosslinking with sodium trimetaphosphate seemed to be higher than of standard starch. The texture of food grade modified starches much differed from standard counterparts, which make possible to extent the assortment of these type products.

18

Phase transitions of potato starch hydrolysates differing in branching characteristics

63%

Ziobro R., Gambus H., Gumul D., Praznik W., Jankowski T.

Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology

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2005

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tom 08

|

nr 3

19

Ocena przydatności preparatów skrobi ziemniaczanej ekstrudowanej do adsorpcji miedzi, ołowiu i cynku

63%

Tomaszewska-Ciosk E., Boruczkowski T., Zdybel E., Drozdz M., Boruczkowska H.

Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin

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2012

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nr 266

20

Hydroliza nieskleikowanej skrobi ziemniaczanej preparatami enzymów amylolitycznych

63%

Slominska L., Zielonka R., Jaroslawski L., Buszka M.

Biuletyn Instytutu Hodowli i Aklimatyzacji Roślin

|

2012

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nr 266

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