Rheological behaviour of chocolate at different temperatures

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62156489%3A43210%2F18%3A43913321" target="_blank" >RIV/62156489:43210/18:43913321 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.5219/876" target="_blank" >https://doi.org/10.5219/876</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5219/876" target="_blank" >10.5219/876</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Rheological behaviour of chocolate at different temperatures

Popis výsledku v původním jazyce

The rheological behaviour of the chocolate at different temperatures was studied using a concentric cylinder viscometer with precision small samples adapter, temperature sensor and standard spindle. BIO chocolate (100% organic cocoa) has been used for the whole types of experiments. At the first, the range of temperature has been chosen 36 oC, 38 oC, 40 oC, 42 oC, and 44 oC. The shear deformation rate was established from the 0.1 s-1 up to 68 s-1. Rheological behaviour was non-Newtonian (plastic) with inconsiderable yield stress in all temperatures. The chocolate unambiguously demonstrated plastic behaviour and flow curves were fitted by the power law model (Herschel-Bulkley model), Bingham model, and Casson model with taking into account the coefficient of determination R2. The obtained results of rheological behaviour of chocolate can be best described as Casson fluid. Exactly coefficients of models can be used for modelling of flow velocity, volume flow, friction factor, Reynolds number, two dimensional and three dimensional velocity profiles and much more for flow in the real technical elements e.g. pipes, trough, tubes. Finally, temperature dependence of apparent viscosity of chocolate was also continuously measured in the range from 35 oC up to 62 oC. The apparent viscosity decreased in the temperature range. This decrease was fitted using power law equation. The knowledge of the plastic flow behaviour of chocolate is very important, because it is not quite common flow behaviour of foodstuffs.

Název v anglickém jazyce

Rheological behaviour of chocolate at different temperatures

Popis výsledku anglicky

The rheological behaviour of the chocolate at different temperatures was studied using a concentric cylinder viscometer with precision small samples adapter, temperature sensor and standard spindle. BIO chocolate (100% organic cocoa) has been used for the whole types of experiments. At the first, the range of temperature has been chosen 36 oC, 38 oC, 40 oC, 42 oC, and 44 oC. The shear deformation rate was established from the 0.1 s-1 up to 68 s-1. Rheological behaviour was non-Newtonian (plastic) with inconsiderable yield stress in all temperatures. The chocolate unambiguously demonstrated plastic behaviour and flow curves were fitted by the power law model (Herschel-Bulkley model), Bingham model, and Casson model with taking into account the coefficient of determination R2. The obtained results of rheological behaviour of chocolate can be best described as Casson fluid. Exactly coefficients of models can be used for modelling of flow velocity, volume flow, friction factor, Reynolds number, two dimensional and three dimensional velocity profiles and much more for flow in the real technical elements e.g. pipes, trough, tubes. Finally, temperature dependence of apparent viscosity of chocolate was also continuously measured in the range from 35 oC up to 62 oC. The apparent viscosity decreased in the temperature range. This decrease was fitted using power law equation. The knowledge of the plastic flow behaviour of chocolate is very important, because it is not quite common flow behaviour of foodstuffs.

Druh

J_SC - Článek v periodiku v databázi SCOPUS

CEP obor

—

OECD FORD obor

21101 - Food and beverages

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Potravinárstvo

ISSN

1338-0230

e-ISSN

—

Svazek periodika

12

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

SK - Slovenská republika

Počet stran výsledku

6

Strana od-do

123-128

Kód UT WoS článku

—

EID výsledku v databázi Scopus

2-s2.0-85043486139