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  1. 8 Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology

  2. 4 Teka Komisji Motoryzacji i Energetyki Rolnictwa

  3. 4 Żywność Nauka Technologia Jakość

  4. 2 Acta Scientiarum Polonorum. Technologia Alimentaria

  5. 2 Polish Journal of Food and Nutrition Sciences

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Autorzy help

  1. 5 Lewandowicz G.

  2. 4 Mitrus M.

  3. 3 Blaszczak W.

  4. 3 Fortuna T.

  5. 3 Gambus H.

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  1. 2 2017

  2. 1 2014

  3. 1 2013

  4. 3 2012

  5. 2 2011

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1

Changes in microstructure of native starches and starch acetates of different botanical origin during retrogradation

100%
Blaszczak W., Fornal J., Lewandowicz G.
Polish Journal of Food and Nutrition Sciences
|
2001
|
tom 10
|
nr 2
Water 2% starch suspensions prepared from native cereal starches (wheat, corn) and tuber ones (potato, tapioca) as well as their acetates were cooked at 100°C for 1 h. The obtained pastes were cooled to 25°C and stored at 4°C for 56 days. Rétrogradation of 2% pastes was determined in two ways: as actual changes in the turbidity development, and as relative rates of turbidity between gels during 56 days of storage. The obtained results showed that the development of turbidity of the native and consequently acetylated starches followed the order: wheat > corn starch > potato > tapioca. Rétrogradation evoked significant changes in microscopic pictures of pellets and supernatants obtained by LM and SEM examinations. The pictures varied considerably in amylose distribution. These alternations were unique for each botanical source of starch as well as starch acetates. The native cereal starches were characterized by a strong association of amylose particles with amylopectin fraction. While the tuber starches showed a weaker interaction between granule remnants and precipitated amylose. Changes in the microstructure of the native and acetylated starch granules were in accordance with turbidometric analysis.
2

Fed-batch simultaneous saccharification and ethanol fermentation of native corn starch

86%
Szymanowska D., Grajek W.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2009
|
tom 08
|
nr 4
5-16
Background. The most important innovations in boethanol production in the last decade were: simultaneous saccharification and fermentation processes (SSF), high gravity fermentation, the use of new enzyme preparation able to hydrolyse native granular starch and construction of genetically modified strains of microorganisms able to carry out simultaneous production of hydrolytic enzymes and fermentation of C6 and C5 sugars. The aim of this study was to assess the efficiency of ethanol fermentation using new type of amylolytic enzymes able to hydrolyse native corn starch in a SSF process. Material and methods. The simultaneous saccharification and fermentation of raw corn flour by fed-batch processes using Saccharomyces cerevisiae strain Red Star Ethanol Red and Stargen 001 enzyme preparation was performed. As experimental variable were investigated: fermentation temperature (35-37-40°C), rate of mash stirring (100 and 200 rpm), fermentation time (0-92 h) and dosage of corn flour (different portion and different time). Results. It was found that optimal temperature for fed-batch SSF process was 37°C at initial pH of 5.0. However, the yeast intensively fermented the saccharides also at 40°C. The fermentation stirring rate has significant effect on starch utilization and fermentation production. The prolongation of fermentation time over 72 h has no substantiation in additional ethanol production. In all experimental fermentations the level of produced organic acids was very low, significantly below toxic concentration for the yeast. Conclusions. It was stated that the use of new method of starch raw material preparation resulted in satisfied fermentation yield and allowed to reduce energy requirements for starch liquefaction
3

Retrogradation of starches and maltodextrins of origin various

86%
Sobolewska-Zielinska J., Fortuna T.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2010
|
tom 09
|
nr 1
71-81
Background. The retrogradation which occurs during the processes food storage is an essential problem in food industry. In this study, the ability to retrogradate of native starches and maltodextrins of different botanical origin was analysed. Material and methods. The materials were starches of various botanical origin, including commercial samples: potato, tapioca, wheat, com, waxy com starches, and laboratory isolated samples: triticale and rice starches. The above starches were used as material for laboratory production of maltodextrins of medium dextrose equivalents (DE in the rangę fforn 8.27 to 12.75). Starches were analysed for amylose content, while the ratio of nonbranched/long-chain-branched to short-chain-branched fractions of maltodextrins was calculated from gel permeation chromatography data. The susceptibility to retrogradation of 2% starch pastes and 2% maltodextrin Solutions was evaluated according to turbidimetric method of Jacobson. Results. The greatest starch in turbidance of starch gels was observed within initial of the test. days. Initial retrogradation degree of cereal starches was higher than that of tuber and root starches. The waxy com starch was the least prone to retrogradate. The increase in turbidance of maltodextrin Solutions were minimal. Waxy com maltodextrin was not susceptible to retrogradation. Among other samples, the lowest susceptibility to retrogradation after 14 days was found for rice maltodextrin, while the highest for wheat and triticale maltodextrin. Conclusions. On the basis of this study, the retrogradation dependence on the kind of starches and the maltodextrins was established and the author stated that all the maltodextrins have a much less ability to retrogradation than the native starches.
4

Preperation of unbranched glucans by hydrolysis of starch of various botanical origin with pullulanase

86%
Kujawski M., Ziobro R., Gambus H.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2003
|
tom 06
|
nr 2
The use of pullulanase preparation was checked as a method to obtain long unbranched glucans from native starch. Different starch sources as well as various solubilisation procedures were tried in order to choose the optimal one. Dissolving in NaOH proved to be suitable for all starch sources, while autoclave should be avoided in case of cereal starches. Potato starch gave clear solutions irrespective of solubilisation method, which were highly susceptible to enzymatic attack. Basing on the results obtained by size exclusion chromatography it was concluded that the time of incubation with the enzyme needed to completely degrade amylopectin molecules is short in comparison to the time needed to hydrolyse all available glycosidic bonds.
5
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Starch granule porosity and its changes by means of amylolysis

86%
Sujka M., Jamroz J.
International Agrophysics
|
2007
|
tom 21
|
nr 1
6

Phase transitions of potato starch hydrolysates differing in branching characteristics

72%
Ziobro R., Gambus H., Gumul D., Praznik W., Jankowski T.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2005
|
tom 08
|
nr 3
7
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Content available

Extrusion-cooking of wheat starch

72%
Mitrus M., Wojtowicz A.
Teka Komisji Motoryzacji i Energetyki Rolnictwa
|
2011
|
tom 11C
During the study the impact of extrusion-cooking process parameters on the wheat starch physical properties changes was investigated. The process was characterized by small energy consumption within a range 270-1069 kJkg-1. Extrusion-cooking technique allows creating the degree of gelatinization of processed starch. It is possible to achieve low or high level of gelatinization depending on the process parameters. Expansion index of the extrudates decreased with increase of wheat starch moisture content. It was found that the use of the extrusion process resulted in increase of water absorption and cold water solubility of starch. The highest value of WAI was 690% and WSI was 19%.
8
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Selected aspects of thermoplastic starch production

72%
Combrzynski M., Mitrus M., Moscicki L., Oniszczuk T., Wojtowicz A.
Teka Komisji Motoryzacji i Energetyki Rolnictwa
|
2012
|
tom 12
|
nr 1
9
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Content available

Effect of native starch on processing and vulcanizing properties of rubber blends

72%
Oravec J., Preto J., Jurkovic P., Matyasovsky J., Chodak I., Oravcova A.
Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology
|
2013
|
tom 83
10
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Content available

Structural changes of corn starch during fuel ethanol production from corn flour

72%
Szymanowska-Powalowska D., Lewandowicz G., Blaszczak W., Szwengiel A.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
|
2012
|
tom 93
|
nr 3
11

Air oxidation of potato starch over zinc (II) catalyst

72%
Gumul D., Gambus H., Gibinski M.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2005
|
tom 08
|
nr 4
12
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Changes of specific mechanical energy during extrusion-cooking of potato starch

72%
Mitrus M., Oniszczuk T., Moscicki L.
Teka Komisji Motoryzacji i Energetyki Rolnictwa
|
2011
|
tom 11C
The simplest method of physical modifi cation of starch is extrusion-cooking. Changes of the extruder efficiency and specific mechanical energy (SME) during extrusion-cooking of potato starch are presented in the paper. Extrusion-cooking process was characterised by good efficiency. The output depended mainly on the extruder screw speed and starch moisture content, less on process temperature. It ranged between the 11.3 kgh-1 and 28 kgh-1 depending on process parameters. SME measurements showed that extrusion-cooking of potato starch is related with rather low energy input ranged from 0.083 to 0.275 kWhkg-1. Significant impact on the values of the SME had a screw speed, very little impact had a moisture content of the raw material.
13

The changes in the internal structure of starch granules caused by oxidation

72%
Pietrzyk S.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2005
|
tom 08
|
nr 2
Native starches, such as potato, wheat, maize, and waxy maize, were subject to oxidation with sodium chlorate(I), hydrogen peroxide in the presence of Cu2+ ions, and sodium chlorate(III) in the presence of formaldehyde. Native starches and their modified preparations were determined for the content of carboxyl and aldehyde groups. In order to determine changes in the internal structure of starch granules, thermodynamic characterization of phase transitions (DSC) was taken and the degree of crystallinity with X-ray diffractions was determined. Potato starch, after oxidation with the applied reagents, became slightly more crystalline, while cereal starches were affected very little. The thermodynamic gelatinization indices obtained for oxidized starches were only changed a small amount in comparison to native ones, which means that the internal structure of the granules is almost unaffected by oxidation.
14

The influence of the growth temperature on structural and thermodynamic properties of starches

72%
Yuryev V. P., Genkina N. K., Wasserman L. A.
Żywność Nauka Technologia Jakość. Suplement
|
2002
|
tom 09
|
nr 4
Effects of environmental factors on composition, structure, and physicochemical properties of native starches from different plants have been extensively studied. Among parameters to which attention was paid were environmental factors there is a growth (soil) temperature during plants development (growth temperature) that plays one of the most important role. The application of different physical approaches for a description of the thermodynamic melting parameters of starches allows to determine the cooperative melting unit, the thickness of crystalline lamellae and to evaluate the role of defects in the structural organization of native granules at changes of growth temperature. As example it is considered the influence of growth temperature of plants on the properties of normal potato and sweet potato starches as well as waxy, normal and high-amylose barley starches, i.e. starches with different polymorphous structures of B-, C- and A- types, correspondingly. The nature of calorimetric peaks doubled for some lormal and high-amylose barley starches at a decrease in growth temperature is discussed.
15

Gelatinization parameters of starch and some cereal products, as determined thermomechanically from torque measurements

58%
Wianecki M., Kolakowski E.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2007
|
tom 10
|
nr 4
16

Comparison of the stability of buttery aroma in gels prepared with maize or potato starch

58%
Bortnowska G.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2009
|
tom 12
|
nr 3
17

Rheological properties of cross-linked E 1422 starches in high concentration sugars systems

58%
Le Thanh-Blicharz J., Walkowski A., Voelkel E., Bryla A., Lewandowicz J.
Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze
|
2014
|
nr 3
18

Wplyw zastosowanego rozpuszczalnika organicznego na stopien podstawienia skrobi i jej pochodnych kwasem laurynowym

58%
Boruczkowska H., Boruczkowski T., Leszczynski W., Drozdz W., Zolnierczyk A.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2008
|
tom 530
459-468
Skrobia, dzięki swej budowie polimeru złożonego z reszt glukozowych oraz obecności w nich wysoce reaktywnych wolnych grup hydroksylowych może ulegać różnym modyfikacjom. Jednym z typów modyfikacji jest wprowadzenie do cząsteczek skrobi grup związanych z nią wiązaniami estrowymi. Produkty tych, jak i innych modyfikacji różnią się właściwościami od skrobi naturalnej. Korzystne właściwości funkcjonalne posiadają estry skrobi z długołańcuchowymi kwasami tłuszczowymi. Estryfikacja skrobi tymi kwasami może być dokonywana metodą enzymatyczną, co zapobiega zanieczyszczeniu środowiska oraz zapewnia wysoką czystość produktu. Reakcje enzymatycznej estryfikacji prowadzone są w polarnym rozpuszczalniku organicznym dobieranym w zależności od stosowanych substratów i użytego enzymu. Celem pracy było określenie przydatności rozpuszczalnika organicznego (tert-butanol lub aceton) w reakcji enzymatycznej estryfikacji skrobi naturalnej i fizycznie modyfikowanej oraz produktów jej depolimeryzacji kwasem laurynowym. Proces prowadzono stosując takie same ilości substratów i czas reakcji tak w środowisku tert-butanolu, jak i acetonu. Estryfikowano skrobię ziemniaczaną naturalną, ekstrudowaną w temperaturze 50-60-70 lub 140-150-160°C, dekstrynę białą oraz maltodekstrynę N. Użyto enzymu Novozymes 435 pochodzącego z drożdży Candida antarctica. Istnienie wiązania estrowego w produkcie potwierdzano przez analizę FTIR. Przydatność użytego rozpuszczalnika określano na podstawie pomiaru stopnia podstawienia skrobi i jej pochodnych kwasem laurynowym. Stopień podstawienia obliczony na podstawie analizy spektrum ¹HNMR 10-u uzyskanych produktów wahał się w granicach od 0,22 do 1,00. Stwierdzono, że zależy on od zastosowanego rozpuszczalnika organicznego jak również od użytego substratu. Wyższe stopnie podstawienia uzyskano w reakcjach prowadzonych w środowisku acetonu. Jedynie w przypadku dekstryny białej ester uzyskany w środowisku tert-butanolu charakteryzował się wyższym stopniem podstawienia niż uzyskany w środowisku acetonu (odpowiednio DS = 0,64 i DS = 0,56).
19

Some physicochemical properties of commercial modified starches irradiated with microwaves

58%
Fortuna T., Przetaczek-Roznowska I., Dyrek K., Bidzinska E., Labanowska M.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
|
2008
|
tom 11
|
nr 4
20
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Content available

Rheological properties of extrusion-cooked starch suspensions

58%
Mitrus M., Wojtowicz A., Oniszczuk T., Moscicki L.
Teka Komisji Motoryzacji i Energetyki Rolnictwa
|
2012
|
tom 12
|
nr 1
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