Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: loose density

Sortuj według:

Ogranicz wyniki do:

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Influence of spray drying conditions on beetroot pigments retention after microencapsulation process

100%

Janiszewska E., Wlodarczyk J.

Acta Agrophysica

2013

tom 20

nr 2

In food colorants microencapsulation process, apart from appropriate carrier selection, the determination of the spray drying parameters which can affect the retention of active ingredients is essential. The aim of this study was to investigate the effect of drying parameters on beetroot pigments retention after microencapsulation. Raw material used in the study was the 100% beetroot juice. Low-crystallised maltodextrin DE=11 (MD) was used as the carrier. To obtain 30% dry matter concentration in the solution, the proper amount of maltodextrin was added to beet root juice with 15% of dry matter. Drying was carried out in a spray-drier at disc speed of 39,000 rpm and solution flux rate of 0.3·10-6 and 0.8·10-6 m3 s-1. The inlet air temperature was 120, 140 and 160oC, at a constant air flow rate of 0.0055 m3 s-1. Before drying, viscosity and density of the solutions were measured. Dry matter content, apparent density, loose bulk density of the powder, and porosity were determined. The particle morphology was tested as well. Pigment content was measured by Nillson (1970) and Von Elbe (2001) methods to determine the efficiency of encapsulation. The viscosity and density of solutions of beet juice with maltodextrin was 3.86 mPa s and 1100 kg m-3, respectively. In both cases, the values of viscosity and density were higher compared to the raw juice. Increase of solution flux rate caused a decrease of dry matter content, apparent particle density and loose bulk density. Increase of inlet air temperature caused an increase of dry matter content, average diameter and a decrease of both densities. It was observed that the increase of inlet air temperature caused a decrease in the yellow pigment to a higher degree (47%) than in the violet pigment (17%). However, no clear correlation was observed for violet pigment. There were no changes in porosity and shape factor. The obtained microcapsules were sphere-like in shape, with numerous deep cavities. In the whole experiment the retention of beet root pigments was in the range of 26.7-29.3%.

Sorption properties of selected powdered instant plant beverages

88%

Ruszkowska M.

Acta Agrophysica

2013

tom 20

nr 1

The objective of this study was to evaluate sorption properties, to characterise se-lected physicochemical properties, and to conduct instrumental colour analysis during storage of four instant plant beverages purchased on the Czech market. The evaluation was conducted for four powdered instant plant beverages: oat (I), buckwheat (II), rice (III), and corn (IV) ones. The sorption properties of the investigated products were analysed with the static method by determin-ing isotherms of water vapour sorption. The scope of the study included water activity in the range from 0.07 to 0.98 (25°C). The moisture equilibrium of the system settled within 45 days. Based on the initial weight of the product and changes in water content, equilibrium contents of water were computed and water vapour sorption isotherms were plotted. BET equation in water activity range of 0.07≤aw≤0.33 was used for mathematical interpretation of the course of water vapour sorption isotherms. Applicability of the BET model for the description of plotted isotherms was evaluated based on values of determination coefficient (R2) and standard error of estimation (FitStdErr) that were determined with the use of Jandel-Table Curve 2D v 5.01 software. The evaluation of phys-icochemical properties of the analysed instant powdered products was carried out based on the assessment of granulometric composition, loose and tapped bulk density, Hausner ratio (HR), and Carr index (ICarr). Colour parameters L*, a*, and b* were determined in the international CIE system using a Konica-Minolta CR 400 colorimeter for standard observer 2º and illuminant D 65. The conducted analyses demonstrated that differences in the sorption as well as physicochemical prop-erties of the investigated instant plant beverages were determined, most of all, by the heterogene-ous raw material composition of the analysed products.

Ograniczanie wyników

2 Acta Agrophysica

1 Janiszewska E.

1 Ruszkowska M.

1 Wlodarczyk J.

2 2013

Wyniki wyszukiwania

Influence of spray drying conditions on beetroot pigments retention after microencapsulation process

Sorption properties of selected powdered instant plant beverages