Optimisation of granola breakfast cereal manufacturing process by wet granulation and pneumatic conveying

This study has considered the optimisation of granola breakfast cereal manufacturing processes by wet granulation and pneumatic conveying. Granola is an aggregated food product used as a breakfast cereal and in cereal bars. Processing of granola involves mixing the dry ingredients (typically oats, nuts, etc.) followed by the addition of a binder which can contain honey, water and/or oil. In this work, the design and operation of two parallel wet granulation processes to produce aggregate granola products were incorporated: a) a high shear mixing granulation process followed by drying/toasting in an oven. b) a continuous fluidised bed followed by drying/toasting in an oven. In high shear granulation the influence of process parameters on key granule aggregate quality attributes such as granule size distribution and textural properties of granola were investigated. The experimental results show that the impeller rotational speed is the single most important process parameter which influences granola physical and textural properties. After that binder addition rate and wet massing time also show significant impacts on granule properties. Increasing the impeller speed and wet massing time increases the median granule size while also presenting a positive correlation with density. The combination of high impeller speed and low binder addition rate resulted in granules with the highest levels of hardness and crispness. In the fluidised bed granulation process the effect of nozzle air pressure and binder spray rate on key aggregate quality attributes were studied. The experimental results show that a decrease in nozzle air pressure leads to larger in mean granule size. The combination of lowest nozzle air pressure and lowest binder spray rate results in granules with the highest levels of hardness and crispness. Overall, the high shear granulation process led to larger, denser, less porous and stronger (less likely to break) aggregates than the fluidised bed process. The study also examined the particle breakage of granola during pneumatic conveying produced by both the high shear granulation and the fluidised bed granulation process. Products were pneumatically conveyed in a purpose built conveying rig designed to mimic product conveying and packaging. Three different conveying rig configurations were employed; a straight pipe, a rig consisting two 45° bends and one with 90° bend. Particle breakage increases with applied pressure drop, and a 90° bend pipe results in more attrition for all conveying velocities relative to other pipe geometry. Additionally for the granules produced in the high shear granulator; those produced at the highest impeller speed, while being the largest also have the lowest levels of proportional breakage while smaller granules produced at the lowest impeller speed have the highest levels of breakage. This effect clearly shows the importance of shear history (during granule production) on breakage during subsequent processing. In terms of the fluidised bed granulation, there was no single operating parameter that was deemed to have a significant effect on breakage during subsequent conveying. Finally, a simple power law breakage model based on process input parameters was developed for both manufacturing processes. It was found suitable for predicting the breakage of granola breakfast cereal at various applied air velocities using a number of pipe configurations, taking into account shear histories.

Optimizing the operation of straight-grate iron-ore pellet induration systems using process models

Mathematical models of straight-grate pellet induration processes have been developed and carefully validated by a number of workers over the past two decades. However, the subsequent exploitation of these models in process optimization is less clear, but obviously requires a sound understanding of how the key factors control the operation. In this article, we show how a thermokinetic model of pellet induration, validated against operating data from one of the Iron Ore Company of Canada (IOCC) lines in Canada, can be exploited in process optimization from the perspective of fuel efficiency, production rate, and product quality. Most existing processes are restricted in the options available for process optimization. Here, we review the role of each of the drying (D), preheating (PH), firing (F), after-firing (AF), and cooling (C) phases of the induration process. We then use the induration process model to evaluate whether the first drying zone is best to use on the up- or down-draft gas-flow stream, and we optimize the on-gas temperature profile in the hood of the PH, F, and AF zones, to reduce the burner fuel by at least 10 pct over the long term. Finally, we consider how efficient and flexible the process could be if some of the structural constraints were removed (i.e., addressed at the design stage). The analysis suggests it should be possible to reduce the burner fuel lead by 35 pct, easily increase production by 5+ pct, and improve pellet quality.

The effect of freeze-drying parameters on the cure characteristics of freeze-dried BSA-loaded silicone elastomer

To formulate therapeutic proteins into polymeric devices the protein is typically in the solid state, which can be achieved by the process of freeze-drying. However, freeze-drying not only risks denaturing the protein but it can adversely affect the cure characteristics of protein-loaded silicone elastomers. This study demonstrates that a variation in the parameters of the freeze-dryer can significantly affect the residual moisture content of freeze-dried BSA, which in turn has an effect on the bulk density and flow properties of the BSA. The bulk density and flow properties of the BSA subsequently affect the cure characteristics of BSA-loaded silicone elastomers. An increase in the residual moisture content results in the freeze-dried BSA having a decreased bulk density and poor flow properties which can have a detrimental effect on the cure characteristics of a freeze-dried BSA-loaded silicone elastomer. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012

Process simulation of co-firing torrefied biomass in a 220 MWe coal-fired power plant

Torrefaction based co-firing in a pulverized coal boiler has been proposed for large percentage of biomass co-firing. A 220 MWe pulverized coal-power plant is simulated using Aspen Plus for full understanding the impacts of an additional torrefaction unit on the efficiency of the whole power plant, the studied process includes biomass drying, biomass torrefaction, mill systems, biomass/coal devolatilization and combustion, heat exchanges and power generation. Palm kernel shells (PKS) were torrefied at same residence time but 4 different temperatures, to prepare 4 torrefied biomasses with different degrees of torrefaction. During biomass torrefaction processes, the mass loss properties and released gaseous components have been studied. In addition, process simulations at varying torrefaction degrees and biomass co-firing ratios have been carried out to understand the properties of CO₂ emission and electricity efficiency in the studied torrefaction based co-firing power plant. According to the experimental results, the mole fractions of CO ₂ and CO account for 69-91% and 4-27% in torrefied gases. The predicted results also showed that the electrical efficiency reduced when increasing either torrefaction temperature or substitution ratio of biomass. A deep torrefaction may not be recommended, because the power saved from biomass grinding is less than the heat consumed by the extra torrefaction process, depending on the heat sources. 

Spent coffee grounds for biodiesel production and other applications

This work evaluates the possibility of using spent coffee grounds (SCG) for biodiesel production and other applications. An experimental study was conducted with different solvents showing that lipid content up to 6 wt% can be obtained from SCG. Results also show that besides biodiesel production, SCG can be used as fertilizer as it is rich in nitrogen, and as solid fuel with higher heating value (HHV) equivalent to some agriculture and wood residues. The extracted lipids were characterized for their properties of acid value, density at 15 °C, viscosity at 40 °C, iodine number, and HHV, which are negatively influenced by water content and solvents used in lipid extraction. Results suggest that for lipids with high free fatty acids (FFA), the best procedure for conversion to biodiesel would be a two-step process of acid esterification followed by alkaline transesterification, instead of a sole step of direct transesterification with acid catalyst. Biodiesel was characterized for its properties of iodine number, acid value, and ester content. Although these quality parameters were not within the limits of NP EN 14214:2009 standard, SCG lipids can be used for biodiesel, blended with higher-quality vegetable oils before transesterification, or the biodiesel produced from SCG can be blended with higher-quality biodiesel or even with fossil diesel, in order to meet the standard requirements.

Assessment of the strategies of organic fruit production and fruit drying in Uganda

Organic agriculture in Uganda is developing at a fast pace and despite this trend Uganda is still unable to produce enough fresh and dry organic fruits mainly pineapple to meet the exporters demand. This current research investigated the strategies of farmers at production level by assessing the pros and cons of fruit growing, organic agriculture and fruit drying in order to understand the underlying causal factor for the low production of organic dry fruits in a major fruit producing district of Uganda. The study was carried out in two separate and distinctive areas; one which only produces and export fresh organic pineapple and the other which exports dried fruits (mainly pineapple and papaya). About 10% of the farmers in the two study areas were surveyed using questionnaires which were further followed by semi-structured interviews and participatory rural appraisals activities with various types of farmers in order to understand the different decisions and strategies of farmers. 82% and 74% of farmers in the two study areas grew fruits as it gave better economic returns and for 77% and 90% respectively in the two study areas, the reasons for growing fruit was the ease of selling compared to other crops. All the farmers were relying on coffee husk for growing organic pineapples. However, 50% of the farmers want to grow pineapples (either organic or conventional) but couldn't afford to buy coffee husk. Fruit drying was mainly a strategy to utilize cheap fruits during harvesting seasons for value addition. 71% and 42% of farmers in the two study areas wanted to dry fruits but it was beyond their economic capacity to buy the driers. Decision of the farmers whether to grow fruits or cereals, organic or conventional agriculture and selling the fruits as fresh or dry were dependent mainly on the economic, knowledge and resource availability of each type of practices. It is concluded that the main barrier for an increase in the production of organic dried fruits is at the processing level, and the limited capacity for investments in drying facilities.

Production of pH-responsive microparticles by spray drying: investigation of experimental parameter effects on morphological and release properties

During spray drying, emphasis is placed on process optimisation to generate favourable particle morphological and flow properties. The effect of the initial feed solution composition on the drug release from the prepared microparticles is rarely considered. We investigated the effects of solvent composition, feed solution concentration and drug-loading on sodium salicylate, hydrocortisone and triamcinolone release from spray dried Eudragit L100 microparticles. Eudragit L100 is a pH-responsive polymer whose dissolution threshold is pH 6 so dissolution testing of the prepared microparticles at pH 5 and 1.2 illustrated non-polymer controlled burst release. Increasing the water content of the initial ethanolic feed solution significantly reduced hydrocortisone burst release at pH 5, as did reducing the feed solution concentration. These findings caution that changes in feed solution concentration or solvent composition not only affect particles’ morphological characteristics but can also negatively alter their drug release properties. This work also illustrate that drug-free microparticles can have different morphological properties to drug-loaded microparticles. Therefore, process optimisation needs to be carried out using drug-loaded systems. Depending on the physicochemical properties of the encapsulated API, drug-loading can affect the polymer solubility in the initial feed solution with consequent impact on microparticles morphological and release properties.

EFFECT OF DRYING METHODS ON THE THERMODYNAMIC PROPERTIES OF BLACKBERRY PULP POWDER

Three different types of maltodextrin encapsulated dehydrated blackberry fruit powders were obtained using vibrofluidized bed drying (VF), spray drying (SD), vacuum drying (VD), and freeze drying (FD). Moisture equilibrium data of blackberry pulp powders with 18% maltodextrin were determined at 20, 30, 40, and 50 degrees C using the static gravimetric method for the water activity range of 0.06-0.90. Experimental equilibrium moisture content data versus water activity were fit to the Guggenheim-Anderson-de Boer (GAB) model. Agreement was found between experimental and calculated values. The isosteric heat of sorption of water was determined using the Clausius-Clapeyron equation from the equilibrium data; isosteric heats of sorption were found to increase with increasing temperature and could be adjusted by an exponential relationship. For freeze dried, vibrofluidized, and vacuum dried pulp powder samples, the isosteric heats of sorption were lower (more negative) than those calculated for spray dried samples. The enthalpy-entropy compensation theory was applied to sorption isotherms and plots of Delta H versus Delta S provided the isokinetic temperatures, indicating an enthalpy-controlled sorption process.

Evaluation of some metals in Brazilian coffees cultivated during the process of conversion from conventional to organic agriculture

The aim of this study was to evaluate the presence of nutrients and toxic elements in coffees cultivated during the process of conversion, on organic agriculture, in southwest Bahia, Brazil. Levels of the nutrients and toxic elements were determined in samples of soils and coffee tissues from two transitional organic farms by atomic absorption spectrometry (FAAS). The metals in soil samples were extracted by Mehlich1 and USEPA-3050 procedures. Coffee samples from both farms presented relatively high levels of Cd, Zn and Cu (0.75,45.4 and 14.9 mu g g(-1). respectively), but were still below the limits specified by the Brazilian Food Legislation. The application of statistical methods showed that this finding can be attributed to the addition of high amounts of organic matter during the flowering tree period which can act on the bioavailability of metal ions in soils. (C) 2009 Elsevier Ltd. All rights reserved.

Coffee table-böcker eller praktverk – begrepp, attityder och arbetssätt : Djupintervjuer med grafiska formgivare och förlagsanställda

Åtta semi-strukturerade djupintervjuer genomfördes i syfte att kartlägga svenska formgivares och förlagsanställdas strategiska och kreativa arbetsprocess samt olika attityder vid arbetet med praktverk och coffee table-böcker. Dessa böckers termer och definitioner diskuterades även, samt boktypens förut-sättningar och utmaningar på marknaden. I denna rapport presenteras funna teman rörande dessa tankemönster och attity-der, samt en generell beskrivning av arbetsprocessen. Produktionen av coffee table-böcker och praktverk fanns vara komplex på grund av att den involverade många personer, tog lång tid i anspråk, var kost-sam och hade relativt små vinstmarginaler vilket därmed kunde förenas med vissa risker. Respondenterna upplevde generellt arbetet som spännande, roligt och givande.Studien belyser även förekomsten av en viss diskrepans vad gäller associationerna till termerna ”coffee table-bok” och ”praktverk”. Coffee table-böcker ansågs främst av de förlagsanställda ha ett innehåll av lägre kvalitet jämfört med det hos ett praktverk.

The rite of passage from regular to connoisseur consumer: the role of the taste transformation ritual in the specialty coffee context

Apesar de o campo da cultura de consumo ter abordado o papel do ritual no consumo, definindo e descrevendo este constructo e explicando suas dimensões, significados culturais, elementos, componentes e práticas, assim como revelando a diferenciação nas práticas dos consumidores, nenhuma pesquisa ainda identificou como os consumidores, por meio de práticas de ritual, estabelecem e manipulam suas próprias diferenciações em relação a outros consumidores durante o rito de passagem deles de uma categoria cultural de pessoa para outra. Tendo como base conceitos-chaves da teoria sobre ritual, minha pesquisa aborda o papel do ritual no consume de apreciação. Conduzindo um estudo etnográfico sobre consumo de apreciação de cafés especiais, eu realizei uma imersão no campo, visitando e observando consumidores em cafeterias independentes de destaque na América do Norte – Toronto, Montreal, Seattle e Nova York – de agosto de 2013 a julho de 2014. Eu também realizei uma imersão no contexto de cafés especiais no Brasil em Belo Horizonte e São Paulo, de agosto de 2014 a janeiro de 2015, para comparar e contrastar as culturas de consume de cafés especiais de Brasil, Estados Unidos e Canadá. Eu usei entrevistas longas, observação participante, netnografia, introspecção e análise histórica de artigos de jornais para coletar os dados, que foram interpretados utilizando a abordagem hermenêutica, comparando os consumidores em diferentes estágios durante o rito de passagem de apreciação. Para estender meu entendimento sobre o consumo de apreciação, eu também coletei dados sobre o contexto de consumo de vinho. Nesta tese, eu introduzo a ideia de ritual de transformação do gosto, teorizando sobre o processo do rito de passagem de apreciação, que converte consumidores regulares em consumidores apreciadores. Minha pesquisa revela que consumidores apreciadores são amadores em diferentes estágios do rito de passagem de apreciação. Eles se transformam pelo estabelecimento e reforço de oposições entre o consume de massa e de apreciação. O ritual de transformação do gosto envolve os seguintes elementos: (1) variação nas escolhas de produtos de alta qualidade, (2) o lugar para realizar a degustação, (3) o momento da degustação, (4) o ato de degustar, (5) investimento de tempo e dinheiro, (6) aumento do capital subcultural e social, (7) perseverança no rito de passagem. Os consumidores apreciadores participam da comunidade de consumo de apreciação. Essa comunidade heterogênea é composta por profissionais excelentes, apreciadores e consumidores regulares. As forças que direcionam a comunidade, de acordo com o que foi identificado no estudo, são a produção de capital social e subcultural, emulação do profissional e das práticas de ritual de consumo, tensões de performance entre os membros da comunidade, amizade comercial e jogo de status. Eu desenvolvo uma ampla consideração teórica que desenvolve e estende um número de conceitos em relação a ritual e consumo, gosto, comunidade heterogênea e consumidores apreciadores.

Optimization of osmotic dehydration of papaya followed by air-drying

FERNANDES, Fabiano A. N. et al. Optimization of Osmotic Dehydration of Papaya of followed by air-drying. Food Research Internation, v. 39, p. 492-498, 2006.

Incorporação de cinzas da casca de café na produção de placas cerâmicas para revestimento

Brazil is the world s leading coffee producer. In 2008, 45.99 million of 60 kg bags of benefited coffee were produced. In the process of improvement 50% is grain and 50% is husk, thus, 1.38 million tons of coffee husk are produced annually. The husk is used as combustible in the drying and improvement ovens in the coffee farms, generating ash as residue. These ashes contain a high concentration of alkaline metals and earth metals, mainly K2O and CaO. This work studies the use of this residue in the ceramic tiles industry, as fluxing agents in substitution to the feldspar. Ten mixtures with equal ratios of clay and kaolin, proceeding from Bahia and the residue (varying from 30 to 5%) were defined and produced in uniaxial tool die of 60x20mm with approximately 5 mm of thickness and 45MPa compacting pressure. The samples were fired in four different temperatures: 1100 °C, 1150 °C, 1185 °C and 1200 °C during 60 minutes and characterized by means of X-ray fluorescence, X-ray diffraction, gravimetric thermal analysis and differential thermal analysis. The results of water absorption, apparent porosity, linear shrinkage, XRD, dilatometry, flexural strength and SEM were also analysed. The test specimen with addition of 10% of ash fired in 1200 °C resulted in 0.18% water absorption and 40.77 MPa flexural strength, being classified as porcelain stoneware tiles according to ABNT, UNI and ISO norms

Comparison between freeze and spray drying to obtain powder Rubrivivax gelatinosus biomass

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Quality of mechanized coffee harvesting in circular planting system

A colheita mecanizada de café se destaca como um dos principais avanços tecnológicos em benefício dos produtores, porém, problemas com planejamento no plantio e desenvolvimento da cultura, bem como falhas na regulagem da colhedora, podem acarretar em redução na eficiência da operação, tornando-a mais estressante para a cultura que a colheita manual. Diante disso, o presente trabalho foi realizado no município de Patos de Minas, MG, com o objetivo de avaliar os danos na parte vegetativa e a qualidade da colheita mecanizada do café cultivado em plantio circular sob pivô central, com duas frequências de vibração das hastes, sob o controle estatístico do processo. Observou-se que a bienalidade negativa sobre a cultura reduziram a carga inicial de café, eliminando o efeito das condições de insolação. Os índices de qualidade da colheita apresentaram distribuição assimétrica, com grande variabilidade nas amostras, sendo apenas a eficiência de derriça influenciada pelos eixos avaliados, e se mostrando estável pelo controle estatístico. Os danos causados às plantas pela colheita apresentaram valores desejáveis, não variando em função dos fatores analisados, mas sendo considerado sob controle estatístico.