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Article
Publication date: 13 October 2021

Maria Cecília Evangelista Vasconcelos Schiassi, Vanessa Rios de Souza, Nathila Angela Alves, Amanda Maria Teixeira Lago, Sérgio Henrique Silva, Gabriel Ribeiro Carvalho, Jaime Vilela de Resende and Fabiana Queiroz

The purpose of this paper was to study the effect of botanical origin on the characteristics of single-flower honeys (assa-peixe, coffee, eucalyptus, laranjeira and…

Abstract

Purpose

The purpose of this paper was to study the effect of botanical origin on the characteristics of single-flower honeys (assa-peixe, coffee, eucalyptus, laranjeira and vassourinha), polyfloral (silvestre), extrafloral (sugarcane) and honeydew (bracatinga) during storage.

Design/methodology/approach

The honeys were stored at 14 °C, and the analysis of water activity, color, absorbance, rheological behavior and microscopic analysis were performed during 6 months (T0, T30, T60, T90, T120, T150 and T180 days); quantification of sugars (fructose (F) and glucose (G)), moisture (M), F/G and G/M ratio only at T0.

Findings

All honeys showed changes during storage, and sugarcane honey stood out for presenting greater crystallization, influenced by the high content of glucose and fructose. Coffee honey showed the least crystallization. The crystallization of honeys influenced the increase in water activity, Newtonian viscosity, color and absorbance. The composition of the honeys directly influenced the crystallization process during storage.

Originality/value

Crystallization is a natural process that occurs spontaneously in honey. Thus, the knowledge of the crystallization rate of honeys from different origins (botanical and geographical) during storage, is of great importance and interest for the industry, beekeepers and consumers, since each type of honey crystallizes in different ways and periods.

Details

British Food Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0007-070X

Keywords

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Article
Publication date: 24 July 2007

J. Smirnova, L. Silva, B. Monasse, J‐M. Haudin and J‐L. Chenot

This paper sets out to show the feasibility of the genetic algorithm inverse method for the determination of the parameters of crystallization kinetics laws in isothermal…

Abstract

Purpose

This paper sets out to show the feasibility of the genetic algorithm inverse method for the determination of the parameters of crystallization kinetics laws in isothermal and non‐isothermal conditions, using multiple experiments.

Design/methodology/approach

The mathematical model for crystallization kinetics determination and the numerical methods of its resolution are introduced. Crystallization kinetic parameters determined by approximate physical analysis and the inverse genetic algorithm method are presented. Injection molding simulations taking into account crystallization are performed using the finite element method.

Findings

It is necessary to perform the optimization on two parameters, transformed volume fraction and number of spherulites to obtain correct results. It is possible to use results from different samples, in spite of the dispersion of some values.

Research limitations/implications

Experimental data for isothermal and non‐isothermal conditions were used and obtained good results for the parameters of crystallization kinetics laws from which the evolutions of overall crystallization kinetics and crystalline microstructure were deduced. Nevertheless, the dispersion of the experimental data concerning the number of spherulites obtained with different samples is important. The evolution of the number of spherulites is required for the optimization to get correct results.

Practical implications

An important result of this work is that the genetic algorithm optimization can be applied to this problem where the experiments cannot be performed with a single sample and the experimental data for the number of spherulites have low precision. Even if only the crystallization kinetics was considered, the feasibility in molding simulation has been shown.

Originality/value

Simulation of crystallization in injection molding is very important for a later prediction of the end‐use properties.

Details

Engineering Computations, vol. 24 no. 5
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 20 March 2009

C. Zhang, Y. Huang, Y. Liu, S. Wang and X. Zhang

The purpose of this paper is to study the isothermal and nonisothermal crystallisation kinetics of pure polypropylene (PP), 1 kGy pre‐irradiated PP and 1 kGy…

Abstract

Purpose

The purpose of this paper is to study the isothermal and nonisothermal crystallisation kinetics of pure polypropylene (PP), 1 kGy pre‐irradiated PP and 1 kGy pre‐irradiated PP/syndiotactic 1,2‐polybutadiene (s‐1,2 PB) (90/10) blends by differential scanning calorimetry.

Design/methodology/approach

The Avrami equation, modified Avrami equation, Ozawa equation and the treatment by combining the Avrami and Ozawa equation were used to analyse the isothermal and nonisothermal crystallisation of various samples.

Findings

The s‐1,2 PB acted as a heterogeneous nucleation agent during the crystallisation of the PP/s‐1,2 PB blends and accelerated the crystallisation rate. The Avrami exponent n of the blends implied that the isothermal crystallisation kinetics of the blends followed a three‐dimensional growth via heterogeneous nucleation. The modified Avrami equation was limited to describe the nonisothermal crystallisation process of pure PP and 1 kGy pre‐irradiated PP, but it was successful for the blends. The treatment by combining the Avrami and Ozawa equation described appropriately the nonisothermal crystallisation process and obtained the kinetic parameter F(T) with specific physical meaning. The crystallisation activation energy for isothermal crystallisation and nonisothermal crystallisation of the blends was reduced due to the s‐1,2 PB acting as a heterogeneous nucleating agent during the crystallisation of the blends and accelerating the crystallisation rate.

Research limitations/implications

The Avrami equation, modified Avrami equation, Ozawa equation and the treatment by combining the Avrami and Ozawa equation were compared for analysis of the isothermal and nonisothermal crystallisation of samples. The crystallisation activation energy for isothermal crystallisation and nonisothermal crystallisation was also calculated according to the Arrhenius and the Kissinger method.

Practical implications

The fundamental research on the crystallisation properties of PP/s‐1,2‐PB blends is essential to understand the mutual effects of two components on their crystallisation mechanisms, facilitating to improve the mechanical properties of the final materials.

Originality/value

The isothermal and nonisothermal crystallisation behaviours of PP/s‐1,2 PB blends, especially pre‐irradiated PP/s‐1,2 PB blends, have not been studied systematically yet, though PP/s‐1,2 PB blends were promising materials in terms of both PP toughening and the application of s‐1,2 PB thermal plastic elastomer.

Details

Pigment & Resin Technology, vol. 38 no. 2
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 9 February 2015

Yasamin Soleimanian, Mohammad A. Sahari and Mohsen Barzegar

The purpose of this study was to investigate the efficiency of low temperature fractional crystallization to increase polyunsaturated fatty acid (PUFA) content of fish…

Abstract

Purpose

The purpose of this study was to investigate the efficiency of low temperature fractional crystallization to increase polyunsaturated fatty acid (PUFA) content of fish oil. Effects of temperature, stages of crystallization, rate of cooling, agitation and addition of primary nucleus on separation efficiency were evaluated. Low temperature crystallization of triacylglycerols (TAGs) was used to increase PUFA content of fish oil (initial PUFA content ∼30 g/100 g oil).

Design/methodology/approach

To optimize the fractionation process, the effect of fractionation temperature (7, 5, 0 and −5°C), crystallization procedures, cooling rate, agitation and addition of primary nucleus on PUFA content was evaluated.

Findings

The best relationship between PUFA concentration (45.8 g/100 g oil) and PUFA yield (51.5 per cent) was attained by performing two-stage crystallization of TAGs at the final temperatures of 5 and 0°C under slow cooling rate (3°C h−1 for first fractionation procedure and 0.7°C h−1 for second stage, until the final fractionation temperature, 0°C, was reached) and slow agitation (3 rpm) and in the presence of primary nucleus, which resulted in 50 per cent increase in PUFA content over the original fish oil.

Practical implications

Determination of iodine and saponification values, refractive index, solid fat content, melting point, cholesterol content of original oil and final fractionated product with the highest PUFA ratio showed that fractionation significantly alters physical and chemical properties of the fraction.

Originality/value

Comparison of iodine value, saponification value, refractive index, solid fat content, melting point and cholesterol content of original oil and the final fractionated product (with the highest PUFA ratio) showed that the fractionation process significantly alters mentioned properties of the initial oil.

Details

Nutrition & Food Science, vol. 45 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

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Article
Publication date: 8 June 2012

B. Pajin, I. Radujko, Z. Šereš, D. Šoronja Simović, J. Gyura and M. Sakač

Investigated milk fat fraction differs in physical attributes, first of all in melting point and solid fat content and its influence on crystallization process of cocoa…

Abstract

Purpose

Investigated milk fat fraction differs in physical attributes, first of all in melting point and solid fat content and its influence on crystallization process of cocoa butter i.e. chocolate mass. It means that this fraction slows down crystallization rate, decreases melting point of mixture with cocoa butter and causes chocolate softness. It is very important for quality of chocolate especially chocolate with nuts or sunflower kernel. The aim of this paper was to investigate the influence of low‐melting (26°C) milk fat fraction on crystallization processes in chocolate mass and define the optimal concentration of this fraction with suitable precrystallization temperature time regime. Solid fat content of chocolate which designates the influence of precrystallization changes in chocolate mass with addition of milk fat fractions was investigated.

Design/methodology/approach

The precrystallization was performed in a laboratory crystallizer that is in a modified Brabender pharinograph, which measures the rheological characteristics as indirect parameter of crystallization properties of chocolate mass depending on milk fat fraction concentration and precrystallization temperature. The experiments were performed according to the factorial plan 32 (two factors on three levels) and the results are statistically treated.

Findings

The results showed that the optimal conditions for achieving the satisfactory tempering rate (optimal concentration of crystals in chocolate mass) are addition of 3 per cent low‐melting milk fat fraction and precrystallization temperature of 25°C.

Originality/value

The addition of high‐melting milk fat fraction slows down the chocolate mass crystallization more then low‐melting milk fat fraction. Investigated fraction influenced decreasing in solid fat content of chocolate regardless of precrystallization temperature.

Details

British Food Journal, vol. 114 no. 6
Type: Research Article
ISSN: 0007-070X

Keywords

Content available
Article
Publication date: 4 January 2021

Radosław Wajman

Crystallization is the process widely used for components separation and solids purification. The systems for crystallization process evaluation applied so far, involve…

Abstract

Purpose

Crystallization is the process widely used for components separation and solids purification. The systems for crystallization process evaluation applied so far, involve numerous non-invasive tomographic measurement techniques which suffers from some reported problems. The purpose of this paper is to show the abilities of three-dimensional Electrical Capacitance Tomography (3D ECT) in the context of non-invasive and non-intrusive visualization of crystallization processes. Multiple aspects and problems of ECT imaging, as well as the computer model design to work with the high relative permittivity liquids, have been pointed out.

Design/methodology/approach

To design the most efficient (from a mechanical and electrical point of view) 3D ECT sensor structure, the high-precise impedance meter was applied. The three types of sensor were designed, built, and tested. To meet the new concept requirements, the dedicated ECT device has been constructed.

Findings

It has been shown that the ECT technique can be applied to the diagnosis of crystallization. The crystals distribution can be identified using this technique. The achieved measurement resolution allows detecting the localization of crystals. The usage of stabilized electrodes improves the sensitivity of the sensor and provides the images better suitable for further analysis.

Originality/value

The dedicated 3D ECT sensor construction has been proposed to increase its sensitivity in the border area, where the crystals grow. Regarding this feature, some new algorithms for the potential field distribution and the sensitivity matrix calculation have been developed. The adaptation of the iterative 3D image reconstruction process has also been described.

Details

Sensor Review, vol. 41 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 11 January 2013

Pia Polsa

Crystallization calls for the interaction between mind, body and spirit. While the knowledge of the mind is how we are used to see knowledge creation, the body influences…

Abstract

Purpose

Crystallization calls for the interaction between mind, body and spirit. While the knowledge of the mind is how we are used to see knowledge creation, the body influences the co‐creation and the embodied experience between the researcher and the participant as a human instrument for understanding. Spirit refers to the sensitivity to ethics in preventing the reaffirmation of the stereotypical narratives. The purpose of the article is to demonstrate how body and spirit in addition to mind can provide alternative insights on a research topic.

Design/methodology/approach

The current study focuses on the body and spirit. Self‐reflective empirical narratives from China and India evidence interpretive findings that suggest that crystallization help us to create an emic understanding of those studied and affirms our commitment to them.

Findings

The interpretive findings demonstrate that with help of body and spirit research can move towards indigenous findings of the research site that can be put into action to improve the life of those studied. Two new quality criteria are established to trustworthiness namely indigenousness and action orientation.

Originality/value

The paper contributes to research methodology by demonstrating how in addition to mind generated findings reflections from body and spirit open new avenues to additional findings. It is proposed that knowledge from body and spirit is particularly important in Asian settings because of the Asian culture's holistic view on life and tolerance for multiple truths.

Details

Qualitative Market Research: An International Journal, vol. 16 no. 1
Type: Research Article
ISSN: 1352-2752

Keywords

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Article
Publication date: 28 June 2011

Kuniaki Kawabata

The purpose of this paper is to propose an imaging process method for automatically extracting assessment target regions in images of crystallization wells.

Abstract

Purpose

The purpose of this paper is to propose an imaging process method for automatically extracting assessment target regions in images of crystallization wells.

Design/methodology/approach

The proposed method detects the target by image processing based on saturation variance in images of crystallization wells.

Findings

The proposed method shows high accurate detection performance in a short time.

Practical implications

The method is applicable to automatic crystallization machine. Especially, it is expected to implement to TERA system of RIKEN.

Originality/value

The paper demonstrates target area detection from microscope images based on saturation variance in images of crystallization wells.

Details

Sensor Review, vol. 31 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 28 March 2008

Kuniaki Kawabata, Mutsunori Takahashi, Kanako Saitoh, Mitsuaki Sugahara, Hajime Asama, Taketoshi Mishima and Masashi Miyano

The purpose of this paper is to propose a state discrimination for crystallization samples (droplets), the purpose of which is to discriminate between diffractable…

Abstract

Purpose

The purpose of this paper is to propose a state discrimination for crystallization samples (droplets), the purpose of which is to discriminate between diffractable extracts (crystal) and other objects.

Design/methodology/approach

The line feature from the image of the protein droplet was extracted and the state discriminated using a classifier based on line features. A support vector machine is used as the classifier.

Findings

In order to verify the performance of the proposed method, the growth state was discriminated experimentally using the images taken by TERA, an automated crystallization system. The correction ratio was determined to exceed 80 percent.

Originality/value

Contribution to automated evaluation process of the growth state of protein crystallization samples.

Details

Sensor Review, vol. 28 no. 2
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 8 December 2020

Anil Kr. Aggarwal

This paper deals with the performance optimization and sensitivity analysis for crystallization system of a sugar plant.

Abstract

Purpose

This paper deals with the performance optimization and sensitivity analysis for crystallization system of a sugar plant.

Design/methodology/approach

Crystallization system comprises of five subsystems, namely crystallizer, centrifugal pump and sugar grader. The Chapman–Kolmogorov differential equations are derived from the transition diagram of the crystallization system using mnemonic rule. These equations are solved to compute reliability and steady state availability by putting the appropriate combinations of failure and repair rates using normalizing and initial boundary conditions. The performance optimization is carried out by varying number of generations, population size, crossover and mutation probabilities. Finally, sensitivity analysis is performed to analyze the effect of change in failure rates of each subsystem on availability, mean time to failure (MTBF) and mean time to repair (MTTR).

Findings

The highest performance observed is 96.95% at crossover probability of 0.3 and sugar grader subsystem comes out to be the most critical and sensitive subsystem.

Originality/value

The findings of the paper highlights the optimum value of performance level at failure and repair rates for subsystems and also helps identify the most sensitive subsystem. These findings are highly beneficial for the maintenance personnel of the plant to plan the maintenance strategies accordingly.

Details

International Journal of Quality & Reliability Management, vol. 38 no. 7
Type: Research Article
ISSN: 0265-671X

Keywords

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