Wyniki wyszukiwania

1

The effect of freezing rate on reconstitution properties of freeze-dried apples

100%

Gawalek J.

Annual Review of Agricultural Engineering

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2006

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tom 05

2

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Sorption properties of osmotically-dehydrated and freeze-dried strawberries

100%

Janowicz M., Lenart A., Idzikowska W.

Polish Journal of Food and Nutrition Sciences

|

2007

|

tom 57

|

nr 1

The study was aimed at determining isotherms and kinetics of water vapour adsorption by osmotically-dehydrated and freeze-dried strawberries. An attempt was also undertaken for mathematical description of both isotherms as well as kinetics of water vapour adsorption. The application of a saccharose solution for 3 h at a temperature of 30°C was found to change the internal structure of raw material and to enable achieving a different result during adsorption of water vapour as compared to the non-hydrated strawberries and dehydrated under different parameters. The Lewicki’s equation enables describing, with a high coefficient of correlation, the shape and elucidating the course of the isotherm of water vapour adsorption by freeze-dried strawberries after initial osmotic dehydration with the use of variable parameters of that process.

3

The influence of temperature of freeze-drying process on the mechanical properties of dried mushrooms

100%

Kramkowski R., Banasik K., Gawlik P.

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

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2001

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tom 04

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nr 2

Some mechanical properties of fresh and freeze-dried mushrooms have been described. Modulus of elasticity was determined from the squeezing tests. The set quantities have been related to the heating plate temperature and density of samples. The obtained relationships have been approximated with exponential functions.

4

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

86%

Sepelevs I., Stepanova V., Galoburda R.

Polish Journal of Food and Nutrition Sciences

|

2018

|

tom 68

|

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.

5

Influence of pre-treatment on shrinkage of freeze-dried archaeological oak-wood

86%

Babinski L.

Acta Scientiarum Polonorum. Silvarum Colendarum Ratio et Industria Lignaria

|

2007

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tom 06

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nr 4

The article presents results of the research on the shrinkage of slightly degraded, freeze-dried archaeological oak-wood (Quercus sp.). Before drying, samples of wood were treated with 10, 20, and 30% water solutions of PEG 300, PEG 4000, and sucrose, as well as the mixture of both polyglycols. Dimensional changes in tangential, radial, and longitudinal directions were determined immediately after freeze-drying, and then, after seasoning of the freeze-dried samples in the air at RH 44 and 70%. Shrinkage of untreated and treated freeze-dried oak-wood was considerably smaller, than that of the material, which was dried naturally (ASET from 49 to 97%, ASER from 39 to 98%).

6

Effect of the aerated structure on selected properties of freeze-dried hydrocolloid gels

86%

Ciurzynska A., Lenart A.

International Agrophysics

|

2016

|

tom 30

|

nr 1

7

Impact of freeze drying on the contents of biologically active substances in the fruiting bodies of selected edible mushroom species

86%

Kalbarczyk J.

Acta Agrophysica

|

2003

|

tom 02

|

nr 2[96]

8

The effect of thermal and freeze drying on the content of organic acids and flavonoids in fruit of European cranberry [Oxycoccus palustris Pers.]

72%

Adamczak A., Buchwald W., Kozlowski J., Mielcarek S.

Herba Polonica

|

2009

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tom 55

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nr 3

94-102

The present paper shows the results of a study on the effect of freeze and thermal drying on the content of organic acids and flavonoids in fruit of European cranberry (Oxycoccus palustris Pers.). They indicate a significant effect of drying conditions on the content of the above mentioned active compounds. In lyophilized fruit, distinctly more organic acids but less flavonoids were found than in fruit dried at a temperature of 35–400 C. The largest relative differences were observed in the case of ascorbic acid. Its content in the fruit dried at high temperature, compared to the lyophilized material, was lower by a mean value of 5 mg/100 g of dry matter (DM), that is, by 42% on the average. With regard to the other organic acids (quinic, citric and malic acids), the average difference was 0.9–2.1 g/100 g DM (14–17%). The mean flavonoid content in the thermally dried fruit was larger by 34 mg/100 g DM (converted into hyperoside) and 24 mg/100 g (converted into quercetin), that is on average by 19% as compared to freeze-dried samples.

9

Optimization of energy consumption in the freeze drying process of champignon (Agaricus bisporus L)

72%

Kozak P., Dziki D., Krzykowski A., Rudy S.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

|

2011

|

tom 11C

In this paper, the influence of surface load of heating plates and degree of fineness of champignon fruits (Agaricus bisporus L) on the energy consumption in the freeze drying process was studied. The experimental researches were carried out for five material load levels of heating plates (6, 8, 10, 12, 14 kgm-2) and at the constant temperature (323K) and pressure of heating plates (63 Pa), after preliminary freezing of raw material to 248K. When the heating load was low (form 6 to 8 kgm-2), the degree of fineness of raw material had no influence on the specific energy requirements needed to heat of plates and to dry the raw material. However, the increase of heating load from 10 to 14 kgm-2 resulted in the increase of specific energy inputs with the increasing degrees of fineness.

10

Energy consumption in the freeze - and convection-drying of garlic

72%

Rudy S.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

|

2009

|

tom 09

11

Wplyw aktywnosci wody na wlasciwosci mechaniczne kostek jablka suszonych sublimacyjnie

72%

Rowicka R., Nowak D., Lewicki P. P.

Żywność Nauka Technologia Jakość

|

2002

|

tom 09

|

nr 1

66-78

Celem pracy było określenie wpływu aktywności wody na właściwości reologiczne kostek jabłka suszonych sublimacyjnie. Suszone kostki jabłka były przechowywane w środowiskach, których aktywność wody wynosiła 0,328; 0,432; 0,648 i 0,810. Po zadanym okresie przechowywania poddawano je testowi kompresji-relaksacji. Stwierdzono, że aktywność wody w istotny sposób kształtowała właściwości mechaniczne liofilizowanych jabłek. Podwyższona aktywność wody działała uplastyczniająco na badany materiał i powodowała załamanie jego struktury. Wraz ze wzrostem aktywności wody malała praca potrzebna do odkształcenia kostek jabłka o 50% ich wysokości, zmniejszała się siła niezbędna do odkształcenia materiału, malał udział elementu sprężystego we właściwościach mechanicznych oraz zmniejszała się twardość materiału. W przedziale aktywności wody 0,45-0,55 relaksacja zachodziła najszybciej i w największym stopniu.

12

Production of dry divercin preparations by spray drying and lyophilization

72%

Dembczynski R., Lubbe P., Bialas W., Sip A., Jankowski T., Grajek W., Marecik R., Cyplik P.

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

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2008

|

tom 11

|

nr 2

13

Charakterystyka właściwości fizycznych proszku jabłkowego otrzymanego metodą suszenia pianowo-sublimacyjnego

72%

Jakubczyk E., Gondek E., Głod K.

Acta Agrophysica

|

2010

|

tom 15

|

nr 2[178]

Celem pracy było określenie wpływu dodatku maltodekstryny i zawartości cukru w surowcu na właściwości fizyczne proszku jabłkowego uzyskanego poprzez suszenie pianowo-sublimacyjne soku i koncentratu jabłkowego. Spieniony sok i koncentrat jabłkowy z 2% albuminy i dodatkiem maltodekstryny w zakresie od 0 do 40% mrożono i suszono sublimacyjnie. Susz rozdrabniano i badano właściwości fizyczne otrzymanego proszku: gęstość nasypową i utrzęsioną, gęstość cząstek, porowatość, zwilżalność i rozpuszczalność oraz higroskopijność. Zwiększenie dodatku maltodekstryny od 10 do 40% wpływało na zmniejszenie higroskopijności, gęstości nasypowej i utrzęsionej, poprawę sypkości proszków z soku jabłkowego. Wyższa zawartość cukru w koncentracie sprzyjała lepszej rozpuszczalności i zwilżalności proszków, co mogło wynikać z większej porowatości i mniejszej gęstości złoża.

14

Advanced fruit drying technologies

72%

Bialik M., Wiktor A., Gondek E.

Zeszyty Problemowe Postępów Nauk Rolniczych

|

2019

|

tom 597

15

Two methods of sample preparation for analysis of non-ortho and mono-ortho PCB congeners in the muscles of selected fish species

72%

Witczak A., Chlewinska M.

Acta Ichthyologica et Piscatoria

|

2008

|

tom 38

|

nr 1

Background. Polychlorinated biphenyls (PCBs) are persistent organic pollutants widespread in the environment. Their ability to accumulate in living organisms leads to food contamination, which is the main route of human exposure to PCBs. During analytical procedure of PCB residue determination, losses of these compounds may occur, which contribute to obtaining underestimated analytical results. Adequate analytical method of chlorobiphenyls determination should be applied to avoid the losses and obtain high recoveries and furthermore to enable accurate estimation of the risk of consuming contaminated food. Especially fish, due to the high bioaccumulation, may contain considerable amounts of these compounds. The aim of this study was to determine if the method of sample preparation influences the recovery of non-ortho (PCB 77, 81, 126, 169) and mono-ortho (PCB 105, 114, 156, 157) PCB congeners in selected fish species. Materials and Methods. To prepare samples for chromatographic determination (HP 6890/5973 GC MS) two methods were applied. Fish muscle tissues were dried by rubbing in a mortar with anhydrous sodium sulphate or freeze dried (lyophilised) (LyoLAB 3000). The samples were fortified with a known amount of internal standard (decachlorobiphenyl), and some were additionally fortified with the standard solution of analysed PCB congeners. Results. nternal standard recoveries ranged from 57.61 ± 1.21% to 88.76 ± 4.03% in freeze-dried samples, and from 63.81 ± 5.11% to 97.50 ± 6.14% in samples rubbed with anhydrous sodium sulphate. Following lyophilisation, recoveries of analysed PCB congeners varied from 68.88 ± 11.74% for PCB 157 to 79.18 ± 12.33% for PCB 114. In the samples rubbed with anhydrous sodium sulphate the lowest recovery was determined for PCB 77 (72.40 ± 12.34%), the highest being typical for PCB 156 (83.47 ± 12.86%). Following lyophilisation, toxic equivalents (TEQs) for the examined fish species ranged from 0.0050 ng-TEQ·g-1 dry weight in salmon to 0.0299 ng-TEQ·g-1 dry weight in mackerel. Following rubbing with anhydrous sodium sulphate the highest toxic equivalent (0.0326 ng-TEQ·g-1 dry weight) was calculated for mackerel, and the lowest for salmon (0.0055 ng-TEQ·g-1 dry weight). Conclusion. The research has demonstrated that in most cases the results obtained with both methods have not differed significantly (P < 0.05), although freeze drying resulted in slightly higher losses of PCB congeners. Despite of smaller recoveries, freeze drying can be applied because of solvent saving and easier sample preparation.

16

Production of dry Lactobacillus rhamnosus GG preparations by spray drying and lyophilization in aqueous two-phase system

72%

Leja K., Dembczynski R., Bialas W., Jankowski T.

Acta Scientiarum Polonorum. Technologia Alimentaria

|

2009

|

tom 08

|

nr 4

39-49

Background. Drying is the oldest method of food preservation. It works by removing water from the food, which prevents the growth of microorganisms and decay. Moreover, spray or freeze drying is also used for the preservation of probiotic cultures. The aim of this study was to compare a survival rate of probiotic bacteria Lactobacillus rhamnosus during spray and freeze drying in ATPS. These results were also compared with survival rate of cells dried under the same conditions but suspended only in skim milk, 6% solution of PVP or 6% solution of dextran. Material and methods. The bacteria Lactobacillus rhamnosus GG were suspended and spray or freeze dried in various types of aqueous two-phase emulsions: PVP/dextran, PEG4000/dextran and PEG8000/dextran. These emulsions consisted of different types of polymers and had varying ratio of polymers in dispersed (dextran) and dispersing (PEG and PVP) phases. Results. The research demonstrated that survival rate of bacteria directly after drying depended mainly on protective reagent, rather than on drying method. After 30-day-storage of the dried bacteria cell specimens, the highest survival rate was noted in case of freeze dried cells in milk. In case of spray drying the highest cell survival rate was observed when emulsion PVP3.6%/dextran2.4% was used as a drying medium. Conclusions. Finally, it has been found that cell survival rate was not strongly influenced by the storage temperature of the powder but it depended on the drying medium.

17

Selected aspects of freeze-drying in the production of instantly reconstitutable foodstuffs

72%

Kramkowski R., Stepien B., Peron S.

Acta Agrophysica

|

2003

|

tom 02

|

nr 2[96]

18

Characterisation of garlic freeze drying with the use of differential scanning calorimetry

72%

Kramkowski R., Kaminski E., Serowik M.

Electronic Journal of Polish Agricultural Universities. Series Agricultural Engineering

|

2001

|

tom 04

|

nr 2

Differential Scanning Calorimetry Method (DSC) was used for determining the parameters of garlic freeze drying process. Garlic with moisture content ranging from 17 to 87% in temperatures from -28 to 5°C (245-278 K) was investigated. The transitions, including change of water into ice (crystallization) and condensed inter-crystalline solution into amorphous solid, were considered. The melting point of ice crystallites Tm and glass transition temperature Tg' were read out from the registered thermographs. Critical moisture of garlic, determining the onset of forced drying stage, was estimated.

19

Influence of water activity on mechanical properties of osmotically pretreated dried fruits

72%

Sitkiewicz I., Lenart A.

Acta Agrophysica

|

2002

|

tom 77

20

Experimental study on freeze-drying rate of foodstuffs

72%

Kramkowski R., Kaplon J., Berdzik M.

Acta Academiae Agriculturae ac Technicae Olstenensis. Technologia Alimentorum

|

1998

|

tom 30

Ograniczanie wyników

The effect of freezing rate on reconstitution properties of freeze-dried apples

Sorption properties of osmotically-dehydrated and freeze-dried strawberries

The influence of temperature of freeze-drying process on the mechanical properties of dried mushrooms

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

Influence of pre-treatment on shrinkage of freeze-dried archaeological oak-wood

Effect of the aerated structure on selected properties of freeze-dried hydrocolloid gels

Impact of freeze drying on the contents of biologically active substances in the fruiting bodies of selected edible mushroom species

The effect of thermal and freeze drying on the content of organic acids and flavonoids in fruit of European cranberry [Oxycoccus palustris Pers.]

Optimization of energy consumption in the freeze drying process of champignon (Agaricus bisporus L)

Energy consumption in the freeze - and convection-drying of garlic

Wplyw aktywnosci wody na wlasciwosci mechaniczne kostek jablka suszonych sublimacyjnie

Production of dry divercin preparations by spray drying and lyophilization

Charakterystyka właściwości fizycznych proszku jabłkowego otrzymanego metodą suszenia pianowo-sublimacyjnego

Advanced fruit drying technologies

Two methods of sample preparation for analysis of non-ortho and mono-ortho PCB congeners in the muscles of selected fish species

Production of dry Lactobacillus rhamnosus GG preparations by spray drying and lyophilization in aqueous two-phase system

Selected aspects of freeze-drying in the production of instantly reconstitutable foodstuffs

Characterisation of garlic freeze drying with the use of differential scanning calorimetry

Influence of water activity on mechanical properties of osmotically pretreated dried fruits

Experimental study on freeze-drying rate of foodstuffs