scholarly journals Influence of freeze-drying conditions on orange powder flowability

Author(s):  
María del Mar Camacho ◽  
Mariana Usganda ◽  
Andrea Silva ◽  
Luis Egas ◽  
Nuria Martínez-Navarrete

Freeze-drying may be a good alternative to get less perishable fruit products. The objective of the present study was to evaluate the impact of freeze-drying conditions of an orange puree on some flow related and rehydration properties of the obtained powders. The results showed that the application of heat during freeze-drying does not affect the parameters studied. However, the partial dehydration of the initial sample results in a lesser porosity and wettability values. Keywords: freeze-drying; porosity; wettability; angle of repose; particle size distribution 

2013 ◽  
Vol 701 ◽  
pp. 415-419
Author(s):  
Salam A. Mohammed ◽  
Ezzat C Abdullah ◽  
Abdul Aziz A. Raman

Flowability indicates the degree of ease of flow. For dynamic (or aerated) flowability, Hausner Ratio (HR) and Angle of Repose (AOR) have been established as a strong indicator for flowability. In this work the influence of particle size and relative humidity (RH) on the flowability of silica gel and ballotini powders were investigated using a non-aerated method. The non-aerated method is a cohesion index (CI) measurement based on a Stable Micro Systems TA.XT PLUS texture analyzer (SMS). The results of the indicator measured confirmed the general expectation that the fine powders are cohesive and the coarse powders are free-flowing at low RH. An interesting trend was observed on the humidity effect study where in low humidity, the powder maintained to be more free-flowing than the powder after the drying process up to a certain limit of RH. However at humidity above this limit, the flowability indicator of the powder is decreasing below than the measureed dry powder flowability. Moreover the apparatus has proven equipment ability to predict even small changes in cohesion value and that using non-aerated methods is greatly important to evaluate the flowability and the powder behavior under different conditions (dynamic and static). It is observed that there are numerous factors related with powder flowability.


Foods ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 32 ◽  
Author(s):  
Marilú A. Silva-Espinoza ◽  
Charfedinne Ayed ◽  
Timothy Foster ◽  
María del Mar Camacho ◽  
Nuria Martínez-Navarrete

Fruits are essential for a healthy diet, as they contribute to the prevention of cardiovascular diseases and some cancers, which is attributed to their high bioactive compound content contributing to their antioxidant capacity. Nevertheless, fruits have a short shelf life due to their high-water content, and freeze-drying is a well-known technique to preserve their nutritive quality. However, it is an expensive technology, both due to the use of low pressure and long processing time. Therefore, an optimisation of variables such as the freezing rate, working pressure and shelf temperature during freeze-drying may preserve fruit quality while reducing the time and costs. The impact of these variables on colour, porosity, mechanical properties, water content, vitamin C, total phenols, β-carotene, and antioxidant activity of a freeze-dried orange puree was evaluated. The results showed a great impact of pressure and shelf temperature on luminosity, chroma and water content. Vitamin C and β-carotene were more preserved with higher shelf temperatures (shorter times of processing) and lower pressure, respectively. The optimum freeze-drying conditions preserving the nutrients, and with an interesting structural property, perceived as a crunchy product by consumers, are low pressure (5 Pa) and high shelf temperature (50 °C).


Drug Research ◽  
2017 ◽  
Vol 68 (03) ◽  
pp. 168-173 ◽  
Author(s):  
Saeed Ghanbarzadeh ◽  
Hadi Valizadeh ◽  
Shadi Yaqoubi ◽  
Arash Asdagh ◽  
Hamed Hamishehkar

Abstract Background Tablets and capsules are the most accepted and widely used solid dosage forms in the medical therapy. Flow property of the powders is playing a key role in the various pharmaceutical fields especially in the fomulation of tablets and capsules. The high hygroscopic crystalline structure of anhydrous Divalproex sodium (DVX) makes it to be appear as waxy white flakes with almost no powder flowability which cause serious problems during the tabletting and capsule filling procedures. Purpose The main objective of this study was to improve the flowability of DVX powder. Methods DVX was mixed with mannitol or lactos in different ratios, dissolved in water and differet binary mixtures of ethanol:water, and finally spray dried with different spray drying conditions. Particle size and powders morphology were assessed by Scanning Electron Microscopy (SEM). The poweder flowability was assessed by measurmet of Hausner ratio (HR), Carr’s index (CI) and angle of repose (AOR) indexes. Furthermore, the content uniformity of DVX in spray-dried powders was determined by using a validated HPLC technique. Results The results showed that spray drying technique improved DVX flowability by forming spherical particles with narrow size distribution AOR value of DVX was decrease from not flowable to 36.1° in spray dried solid dispersion indicating the improvmet of powder flowability from very poor to fair/good condition. Conclusion Findings suggest that the spray drying technique improves DVX flowability and may pave the way for improvement in the tabletting procedure of DVX.


2021 ◽  
Vol 25 (1) ◽  
pp. 135-146
Author(s):  
Marek Domin ◽  
Magdalena Ćwiklińska ◽  
Małgorzata Góral-Kowalczyk

Abstract The objective of the paper was to describe the impact of freeze-drying conditions on hardness of lyophilizates obtained based on soft fruit pomace. Raspberry, cherry, and grape pomace from the pressing process carried out with a low-speed rotary press constituted a research material. Immediately after the pressing process, pomaces were placed in forms, frozen, and after freezing they were freeze-dried in the pressure of 20, 42, 63, 85 and 110 Pa. The obtained lyophilizates were subjected to the measurement of hardness with the use of texture meter equipped with a penetrometer in the form of a cone with a vertical angle of 30°. The increase of pressure during freeze-drying of samples was accompanied by the increase of hardness of the obtained lyophilizates, which may affect the energy consumption of the grinding process and the nature of rehydration of the final product. Moreover, the water content of raw material, pomaces, and lyophilizates was determined. The obtained results of measurements were subjected to a statistical analysis which showed that the pressure of freeze-drying significantly diversifies the hardness of the obtained lyophilizates.


2019 ◽  
Vol 65 (1) ◽  
Author(s):  
Arif Delviawan ◽  
Yoichi Kojima ◽  
Hikaru Kobori ◽  
Shigehiko Suzuki ◽  
Kenji Aoki ◽  
...  

AbstractCommercial wood flour of pine (Pinus densiflora) was used as an experimental material. It was milled with different milling times 0, 10, 20, 30, 40, 60, and 120 min to investigate the effect of their particle size distribution on the mechanical properties of the wood–plastic composite. Two kinds of drying conditions, 7 days of freeze-drying at a temperature of −45 °C and heat drying (80 °C) for 24 h were applied. Polypropylene and maleic anhydride-grafted polypropylene were used as a matrix and the compatibilizer of the wood–plastic composite compound, respectively. Particle size analysis showed that an increase in the time of ball milling decreased the wood flour size. However, an excessive milling period of time longer than 40 min corresponded to an increase in the amount of aggregation. Scanning electron microscope images showed the existence of aggregation for the wood flour with 120 min of wet milling time. As the particle size decreased, mechanical properties of wood–plastic composite increased for up to 30 min of wet milling time and then slightly decreased. This behavior might be due to aggregation. The optimum mechanical property was obtained at 30 min of wet milling time under freeze-drying conditions.


Author(s):  
И.В. Бачериков ◽  
Б.М. Локштанов

При проектировании открытых и закрытых хранилищ измельченных сыпучих материалов древесных материалов, таких как щепа и опилки, большое значение имеет угол естественного откоса (статический и динамический) этих материалов. В технической литературе приводятся противоречивые сведения о величине этих углов, что приводит к ошибкам при проектировании складов. В справочных данных не учитываются условия, в которых эксплуатируются емкости для хранения сыпучих материалов, свойства и состояние этих сыпучих материалов. В свою очередь, ошибки при проектировании приводят к проблемам (зависание, сводообразование, «затопление» и т. д.) и авариям при эксплуатации бункеров и силосов на производстве. В статье представлены сведения, посвященные влиянию влажности и температуры на угол естественного откоса сыпучих материалов. На основании лабораторных и натурных экспериментов, проведенных с помощью специально разработанных методик и установок, была скорректирована формула для определения углов естественного откоса (статического и динамического) для измельченных древесных материалов в зависимости от их фракционного и породного состава, влажности (абсолютной и относительной) и температуры. При помощи скорректированной формулы можно определить угол естественного откоса древесных сыпучих материалов со среднегеометрическим размером частицы от 0,5 мм до 15 мм (от древесной пыли до технологической щепы) в различных производственных условиях. Статья может быть полезна проектировщикам при расчете угла наклона граней выпускающей воронки бункеров и силосов предприятий лесной отрасли и целлюлозо-бумажной промышленности. In the design of open and closed storage warehouses chopped wood materials for bulk materials such as wood chips and sawdust, great importance has an angle of repose (static and dynamic) of these materials. In the technical literature are conflicting reports about the magnitude of these angles, which leads to errors in the design of warehouses. In the referencesdoes not take into account the conditions under which operated capacities for storage of bulk materials, and properties and condition of the bulk material. The design errors lead to problems (hanging, arching, «flooding», etc.) and accidents in the operation of hoppers and silos at the mills. The article provides information on the impact of humidity and temperature on the angle of repose of granular materials. On the basis of laboratory and field experiments, conducted with the help of specially developed techniques and facilities has been adjusted formula for determining the angle of repose (static and dynamic) for the shredded wood materials depending on their fractional and species composition, humidity (absolute and relative) and temperature. It is possible, by using the corrected formula, to determine the angle of repose of loose wood materials with average particle size of from 0.5 mm to 15 mm (wood dust to pulpchips) in various operating conditions. The article can be helpful to designers in the calculation of the angle of inclination of the funnel faces produces bunkers and silos forest industries and pulp and paper industry.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1420
Author(s):  
Faith Seke ◽  
Vimbainashe E. Manhivi ◽  
Tinotenda Shoko ◽  
Retha M. Slabbert ◽  
Yasmina Sultanbawa ◽  
...  

Natal plums (Carissa macrocarpa) are a natural source of bioactive compounds, particularly anthocyanins, and can be consumed as a snack. This study characterized the impact of freeze drying and in vitro gastrointestinal digestion on the phenolic profile, antioxidant capacity, and α-glucosidase activity of the Natal plum (Carissa macrocarpa). The phenolic compounds were quantified using high performance liquid chromatography coupled to a diode-array detector HPLC-DAD and an ultra-performance liquid chromatograph (UPLC) with a Waters Acquity photodiode array detector (PDA) coupled to a Synapt G2 quadrupole time-of-flight (QTOF) mass spectrometer. Cyanidin-3-O-β-sambubioside (Cy-3-Sa) and cyanidin-3-O-glucoside (Cy-3-G) were the dominant anthocyanins in the fresh and freeze-dried Natal plum powder. Freeze drying did not affect the concentrations of both cyanidin compounds compared to the fresh fruit. Both cyanidin compounds, ellagic acid, catechin, epicatechin syringic acid, caffeic acid, luteolin, and quercetin O-glycoside from the ingested freeze-dried Natal plum powder was quite stable in the gastric phase compared to the small intestinal phase. Cyanidin-3-O-β-sambubioside from the ingested Natal plum powder showed bioaccessibility of 32.2% compared to cyanidin-3-O-glucoside (16.3%). The degradation of anthocyanins increased the bioaccessibility of gallic acid, protocatechuic acid, coumaric acid, and ferulic acid significantly, in the small intestinal digesta. The ferric reducing antioxidant power (FRAP), 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) activities, and inhibitory effect of α-glucosidase activity decreased in the small intestinal phase. Indigenous fruits or freeze-dried powders with Cy-3-Sa can be a better source of anthocyanin than Cy-3-G due to higher bioaccessibility in the small intestinal phase.


Author(s):  
Wojciech Sobieski

AbstractThe paper describes the so-called Waterfall Algorithm, which may be used to calculate a set of parameters characterising the spatial structure of granular porous media, such as shift ratio, collision density ratio, consolidation ratio, path length and minimum tortuosity. The study is performed for 1800 different two-dimensional random pore structures. In each geometry, 100 individual paths are calculated. The impact of porosity and the particle size on the above-mentioned parameters is investigated. It was stated in the paper, that the minimum tortuosity calculated by the Waterfall Algorithm cannot be used directly as a representative tortuosity of pore channels in the Kozeny or the Carman meaning. However, it may be used indirect by making the assumption that a unambiguous relationship between the representative tortuosity and the minimum tortuosity exists. It was also stated, that the new parameters defined in the present study are sensitive on the porosity and the particle size and may be therefore applied as indicators of the geometry structure of granular media. The Waterfall Algorithm is compared with other methods of determining the tortuosity: A-Star Algorithm, Path Searching Algorithm, Random Walk technique, Path Tracking Method and the methodology of calculating the hydraulic tortuosity based on the Lattice Boltzmann Method. A very short calculation time is the main advantage of the Waterfall Algorithm, what meant, that it may be applied in a very large granular porous media.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1023
Author(s):  
Ji Young Yu ◽  
Piyanan Chuesiang ◽  
Gye Hwa Shin ◽  
Hyun Jin Park

Liposomes have been utilized as a drug delivery system to increase the bioavailability of drugs and to control the rate of drug release at the target site of action. However, the occurrence of self-aggregation, coalescence, flocculation and the precipitation of aqueous liposomes during formulation or storage can cause degradation of the vesicle structure, leading to the decomposition of liposomes. To increase the stability of liposomes, post-processing techniques have been applied as an additional process to liposomes after formulation to remove water and generate dry liposome particles with a higher stability and greater accessibility for drug administration in comparison with aqueous liposomes. This review covers the effect of these techniques including freeze drying, spray drying and spray freeze drying on the stability, physicochemical properties and drug encapsulation efficiency of dry liposomes. The parameters affecting the properties of liposomes during the drying process are also highlighted in this review. In addition, the impact of using a protective agent to overcome such limitations of each process is thoroughly discussed through various studies.


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