Orientadores: José Luiz Pereira, Maristela Nascimento / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T16:21:16Z (GMT). No. of bitstreams: 1 Silva_IvoneFranciscada_M.pdf: 1262965 bytes, checksum: 1fe0878a62acfd4e2e373d7b14691653 (MD5) Previous issue date: 2011 / Resumo: Os microrganismos são extremamente importantes no processamento do cacau, sob dois aspectos. O primeiro é o aspecto tecnológico, porque desempenham um papel fundamental no desenvolvimento do sabor do chocolate. O segundo é o aspecto de saúde pública, porque podem transmitir doenças de origem alimentar. O chocolate já foi incriminado em vários surtos de salmonelose e, em alguns deles, a contaminação por Salmonella originou-se dos ingredientes de cacau. O objetivo do presente estudo foi verificar a ocorrência de enterobactérias, incluindo Salmonella em cada etapa do processamento do cacau até a obtenção do chocolate além de determinar características fisico-químicas como pH e atividade de água. Foram analisadas 364 amostras, obtidas de produtores e processadores de cacau da Bahia e comerciantes de chocolate do Estado de São Paulo, sendo 119 amostras de cacau durante o pré-processamento nas fazendas produtoras; 150 amostras de derivados processados de cacau e 65 amostras comerciais de chocolate. As polpas de cacau apresentaram resultados microbiológicos e físico-químicos de acordo com a legislação vigente. As sementes que chegam do campo, antes de entrarem na fermentação, não apresentaram contaminação por E. coli, o que indica que a matéria prima é uma fonte menos provável de entrada de enteropatógenos, dentre eles Salmonella, no pré-processamento do cacau. Na etapa de fermentação não houve o isolamento de Salmonella, nem foi observada correlação entre a presença ou contagem de E. coli e o tempo de fermentação. Todas as fazendas produtoras apresentaram contaminação por E. coli. Durante a etapa de secagem das amêndoas não foi detectada presença de Salmonella, já a porcentagem de amostras contaminadas por E. coli aumentou em todas as fazendas (40% de amostras contaminadas) com relação a etapa anterior. Nas amêndoas fermentadas e secas foi detectada a presença de Salmonellaem uma amostra, além de ter sido verificado um aumento na porcentagem de amostras contaminadas por E. coli em relação a etapa anterior. Quanto cacau processado, nas amostras de Nibs analisadas houve o isolamento de bactérias do grupo enterobactérias e coliformes totais em 17 e 20% das amostras, mesmo após terem sido submetidos a um processo de torração com temperaturas acima de 110°C. Para os demais produtos foi verificada contaminação de até 7% das amostras analisadas. Em relação ao chocolate as amostras analisadas apresentaram resultados microbiológicos dentro dos padrões estabelecidos pela legislação. Os resultados obtidos nos levam a concluir que: o pré-processamento do cacau é uma etapa onde ocorre a introdução e multiplicação de microrganismos indicadores e patogênicos como a Salmonella, sendo que as etapas de secagem e armazenamento se mostraram as mais críticas; a etapa de processamento também oferece risco de introdução e/ou sobrevivência de microrganismos patogênicos como Salmonella / Abstract: Microorganisms are extremely important in the processing of cocoa for many reasons. First of all is the technological aspect because some microorganims play a key role in the improvement of chocolate flavor. The other aspect is on public health, mainly on the transmission of food-borne diseases. Chocolate has already in several outbreaks of salmonellosis, in some of them Salmonella source was cocoa ingredient. Therefore, the aim of this study was to investigate the occurrence of been Enterobacteriaceae, including Salmonella, throughout cocoa and chocolate chain incremented. Furthermore, physico-chemical properties such as pH and water activity were determined. The amount of 364 samples, obtained from manufacturers of Bahia state and cocoa traders from São Paulo state, were analyzed, including 119 samples of cocoa during the pre-processing on farms, 150 samples of cocoa processed products and 65 samples of commercial chocolate. The results indicated that the microbiological and physical-chemical analyses of the cocoa pulp were according to law. Cocoa sucs before the fermentation process are not. source of Salmonella and E.coli. In the fermentation stage, Salmonella was not isolated, but all farms showed contamination by E. coli, without correlation between the counting of pathogens and fermentation time. In the drying step, Salmonella was not detected as opposed to E. coli counting, that increased 40% in all farms with respect to the previous step. In the storage only one sample showed Salmonella. In Nibs samples were isolated Enterobacteriaceae and total coliforms in respectively 17% and 20% of samples, despite of roasting processing with temperatures above 110ºC. For other products the contamination of 7%. Commercial chocolate samples showed results seconding to the standards established by law.The results lead us to conclude that the pre-processing of cocoa is the stage where there is the introduction and multiplication of indicators microorganisms and Salmonella. The drying and storage were the most critical steps. The processing stages, also offer risk of introduction and survival of pathogens such as Salmonella / Mestrado / Ciência de Alimentos / Mestre em Ciência de Alimentos

<div>Cocoa is widely used by confectionary industries as a powder raw material for chocolate production. The chemical properties such as high- or low-fat content determine the functionality of the cocoa powder and constitute as a major factor in controlling the behavior of the final product. Additionally, the physicochemical properties such as the cohesive characteristics of cocoa powders create undesirable issues in industrial manufacturing settings. Thus, the evaluation of physical and chemical attributes is relevant to differentiate the powder surface structure and define the material behavior in presence of other materials or distinct environments.</div><div>This work evaluated three kinds of cocoa powders—varying mainly on the lipid content—to assess the powder performance in terms of the role of surface properties on the physical attributes (flowability and wettability) and stability under distinct frameworks. Various analytical tools were used, and several methodologies were developed and implemented to determine the surface area, changes in lipid melting phases at the surface level and particle interactions. The characterization methods included particle true density, flow properties under aerated conditions, bulk permeability, thermal properties, surface energetics, water sorption, and chemical surface compositional analyses.</div><div>The findings of this work revealed that the cocoa surface composition, amount of lipids, did not explain the low-flow performance or the water uptake. On the other hand, physicochemical properties such as lipid polymorphism was introduced as an avenue to further understand the results. From the surface energetics standpoint, a water diffusion mechanism is proposed as a result of the observed effect of water on the performance and stability of the cocoa powder systems. Owing to the hydrophobic nature of cocoa particles, this material can be used as a unique reference to understand cohesive particle models with implications on the performance (flowability and wettability) of lipid-based surface materials. The results indicated that powder behavior on the performance is a confounding effect of all variables.</div><div>The major contribution of this thesis work demonstrates the importance of surface chemistry characterization on the physical attributes of cocoa powder systems and the potential to control surface composition to improve the performance and stability of food complex systems.</div>

The food supply chain has gained impulse over the past few years induced by the rising global demand for food; therefore, much emphasis is placed upon examining this class of supply chains. It also faces constant production, storage, and distribution challenges, wherein the key link for proper operation is the farmer, who engages in the agricultural sector, heavily impacted by low crop productivity, which interfer with economic development at a national level. Consequently, it is important to assess those farmers who belong to micro and small enterprises in the agricultural sector. Due to the characteristics of the population, a nonprobability sampling technique was used to assess micro and small cocoa producers in La Convención Province, Cusco, Peru. To such end, a snowball sampling model with distance boundaries was adopted because the population is unknown and hard to reach.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / The objective of this work is to develop a quality management system focused on the principles of TQM for cocoa micro and small enterprises (MSEs) in the province of La Convención, Cusco - Perú. The diagnosis for this investigation was made using in-depth interviews to the cocoa farmers that facilitated the identification of the current situation of cocoa MSEs. With the results obtained and based on the scientific articles studied, the critical elements in each activity related to the cocoa production process were determined, and it is focused on establishing a quality management system adaptable to the requirements of the plots studied. As a result of the analysis of the experts, the system in question is based on the following principles of TQM: documentation, customer focus, process-based approach and continuous improvement.

Tesis por compendio / [ES] «Aplicación de nuevas tecnologías a la alcalinización de cacao» es una tesis doctoral centrada, por un lado, en el estudio de los cambios fisicoquímicos y funcionales causados por dos técnicas de alcalinización alternativas a la convencional y, por otro, en la comparación de dichas propiedades con las de muestras comerciales. En el capítulo I, se describe un sistema de alcalinización basado en extrusión. Esta tecnología se ha aplicado a la alcalinización de cacao dada su capacidad de tratar la materia prima de forma rápida y continúa, y su bajo consumo energético. En primer lugar, se estudiaron los efectos de diversas variables de proceso sobre las propiedades fisicoquímicas y funcionales de cacaos en polvo. En general, de todas las variables, el tipo y la concentración de álcali fueron las principales responsables del incremento de pH, del oscurecimiento de las muestras y de la reducción en el contenido de compuestos funcionales. En cuanto a la humedad, fueron la temperatura y el contenido en agua las que mostraron causar los mayores efectos, llegando a producir reducciones de casi un 50%. Además de evaluarse el efecto de las diferentes variables, en este capítulo también se compararon los cacaos producidos mediante extrusión con los alcalinizados por el método convencional. Los resultados mostraron que la extrusión, en menos de cinco minutos, fue capaz de oscurecer y de producir cacaos en polvo con un perfil sensorial, una capacidad antioxidante y un contenido en polifenoles totales relativamente similar al de los productos comerciales. En cuanto al capítulo II, en este se ha estudiado la técnica de calentamiento por microondas como una alternativa al tratamiento de alcalinización tradicional. La tecnología microondas ha demostrado ser rápida, versátil y capaz de preservar las características funcionales y sensoriales, lo que ha hecho interesante su aplicación a la alcalinización de cacao. En los trabajos que forman este segundo capítulo, se estudiaron los efectos de diversas variables de proceso sobre el producto. En general, el tipo y la concentración de álcali fueron las variables principalmente responsables del oscurecimiento del cacao, del incremento del pH y de la reducción de las concentraciones de catequina y epicatequina. Sin embargo, el álcali empleado no redujo la actividad antioxidante ni al contenido en fenoles totales, propiedades que se vieron incrementadas por la presión, la potencia y la duración del tratamiento. Estos incrementos se relacionaron con la capacidad de estas variables para liberar a los polifenoles no extractables y para promover determinadas reacciones químicas. Además, también se estudió el efecto de las diferentes variables sobre la humedad. La potencia y la duración del tratamiento fueron las que se mostraron esenciales para lograr el secado del producto, llegando a producir reducciones de hasta el 70%. Por otro lado, además de estudiarse el impacto de las diferentes variables, también se compararon cacaos producidos por microondas con muestras producidas por el método convencional para evaluar su similitud con los cacaos comerciales. Los resultados mostraron que el microondas, en solo cuatro minutos, fue capaz de oscurecer el cacao y de mantener un perfil sensorial similar al producido por el método tradicional, a la par que conducía a una mejora en sus propiedades funcionales. En resumen, los métodos para la alcalinización de cacao desarrollados en el marco de la presente tesis doctoral han demostrado ser unas alternativas muy prometedoras a la tecnología convencional. Ambas técnicas no solo han sido capaces de oscurecer el cacao tanto como el método comercial en un tiempo mucho menor, sino que también han conseguido el secado parcial de la muestra y unas características sensoriales y funcionales comparables o incluso mejores que las del método convencional. / [CA] «Aplicació de noves tecnologies a l'alcalinització de cacau» és una tesi doctoral centrada, d'una banda, en l'estudi dels canvis fisicoquímics i funcionals causats per dos tècniques d'alcalinització alternatives a la convencional i, d'altra banda, en la comparació d'aquestes propietats amb les de mostres comercials. En el capítol I, es descriu un sistema d'alcalinització similar al convencional però basat en extrusió. Aquesta tecnologia s'ha aplicat a l'alcalinització de cacau per la seua capacitat de tractar la matèria primera de forma ràpida i continua, i pel seu baix consum energètic. En primer lloc, es van estudiar els efectes de diverses variables de procés sobre les propietats fisicoquímiques i funcionals de cacaus en pols. En general, de totes les variables, el tipus i la concentració d'àlcali van ser les principals responsables de l'increment de pH, de l'enfosquiment de les mostres i de la reducció en el contingut de compostos funcionals. Pel que fa a la humitat, van ser la temperatura i el contingut en aigua les que van causar els majors efectes, arribant a produir reduccions d'un 50%. A més d'avaluar l'efecte de les diferents variables, en aquest capítol també es van comparar els cacaus produïts mitjançant extrusió amb els alcalinizats pel mètode convencional. Els resultats van mostrar que l'extrusió, en menys de cinc minuts, va a ser capaç d'enfosquir i de produir cacaus en pols amb un perfil sensorial, una capacitat antioxidant i un contingut en polifenols totals relativament similar al dels productes comercials. Pel que fa al capítol II, en aquest s'ha estudiat la tècnica de calfament per microones com una alternativa a l'alcalinització tradicional. La tecnologia microones ha demostrat ser ràpida, versàtil i capaç de preservar les característiques funcionals i sensorials, el que ha fet interessant la seua aplicació a l'alcalinització de cacau. En els treballs que formen aquest segon capítol, es van estudiar els efectes de diverses variables de procés sobre el producte. En general, el tipus i la concentració d'àlcali van ser les variables principalment responsables de l'enfosquiment del cacau, de l'increment del pH i de la reducció de les concentracions de catequina i epicatequina. No obstant això, l'àlcali empleat no va reduir l'activitat antioxidant ni al contingut en fenols totals, propietats que es van incrementar per la pressió, la potència i la duració del tractament. Aquests increments es van relacionar amb la capacitat d'aquestes variables per alliberar els polifenols no extractables i per promoure determinades reaccions químiques. A més, també es va estudiar l'efecte de les diferents variables sobre la humitat. La potència i la duració del tractament van ser les que es van mostrar essencials per aconseguir la deshidratació del producte, arribant a produir reduccions de fins al 70%. D'altra banda, a més d'estudiar-se l'impacte de les diferents variables, també es van comparar els cacaus produïts per microones amb mostres produïdes pel mètode convencional per tal d'avaluar la seua similitud amb els cacaus comercials. Els resultats van mostrar que el microones, en només quatre minuts, va ser capaç d'enfosquir el cacau i de mantenir un perfil sensorial similar al produït pel mètode tradicional, al mateix temps que conduïa a una millora en les seues propietats funcionals. En resum, els mètodes per a l'alcalinització de cacau desenvolupats en el marc de la present tesi doctoral han demostrat ser unes alternatives molt prometedores per a substituir la tecnologia convencional. Les dos tècniques no només han estat capaces d'enfosquir el cacau tant com el mètode comercial en un temps molt menor, sinó que també han aconseguit la deshidratació parcial de la mostra i unes característiques sensorials i funcionals comparables a les del mètode convencional. / [EN] "Application of new technologies to cocoa alkalization" is a PhD thesis that aims to study the effects of two alternative techniques on the physicochemical and functional features of alkalized cocoa, and to evaluate their suitability to replace the traditional treatment. In chapter I, the conventional system for alkalization in closed and pressurized vessels has been replaced by extrusion. This technique has been proved to be a fast, continuous and less energy-consuming method, characteristics that the traditional system lacks and that have promoted its application to cocoa alkalization. On the one hand, the effects produced by temperature, water content and alkali type and concentration were evaluated on the physicochemical and functional features of cocoa. In general, alkali type and concentration were the main variables increasing the pH, darkening the sample, but also reducing the functional content, while water content and temperature exerted minor effects. On the other hand, the temperature and the water content were the variables exhibiting the greatest effect on the moisture content, leading to reductions of almost 50%. Moreover, the extrusion alkalization products were compared to traditionally produced cocoa powders based on physicochemical, functional and sensory criteria. The results revealed that extrusion was faster and able to dark cocoa in a greater extent than the conventional treatment and to produce sensory acceptable powders. These results confirm that extrusion is a feasible and promising alternative method able to alkalize cocoa in a fast, continuous and less energy-consuming manner. In chapter II, microwave heating has been studied as a substitute of the traditional alkalization treatment. This heating method has proven to be fast, versatile and able to preserve functional and sensory features of the treated products, which has made interesting its application to cocoa alkalization. The effects of the microwave heating technique on water content, power, duration, pressure application and alkali type and concentration were analyzed. In general, alkali type and concentration were the main variables inducing the darkening of cocoa, increasing its pH and reducing the concentrations of catechin and epicatechin. However, these variables did not affect the antioxidant activity and the total phenol content of the treated cocoas in comparison to the untreated one. Treatment pressure, power and duration exerted positive effects on the antioxidant activity, the total phenol content or both. These changes were related to the capacity of these variables, in combination with the alkali agent, to release non-extractable polyphenols from the matrix and to the induction of different chemical reactions. Additionally, the effects of the different variables were studied on the moisture content. Power and duration of the microwave heating treatment were decisive in the reduction of the water content, which was significantly reduced up to 70%. In terms of the evaluation of the suitability of the developed microwave heating alkalization method, the produced cocoas were compared to the traditionally alkalized ones in their physicochemical, functional and sensory characteristics. The developed fast microwave heating treatment showed to be able to dark cocoa as much as the traditional method, to produce sensory equivalent powders and to lead to the obtaining of cocoas with higher antioxidant activity and phenol content. In conclusion, this PhD thesis has applied extrusion and microwave heating as promising alternatives to cocoa alkalization. These technologies have demonstrated to dark cocoa in a significantly faster fashion than the traditional alkalization treatment, while keeping similar sensory profile and functional features, and substantially drying the product. / The authors would like to acknowledge the financial support of the Spanish Government and European Regional Development Fund (Project RTC-2016-5241- 2) / Valverde García, D. (2020). Application of new technologies to cocoa alkalization [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/140311 / TESIS / Compendio

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Many developing countries that rely heavily on primary commodity exports to provide a major portion of their exchange revenues confront large variability in their incomes. This has been a factor of major concern to the developing countries as revenue instability is considered to deter development as well as affect the welfare of those engaged in production of such commodities. Producing countries have adopted several programs and policies that attempt to lessen the price and revenue instabilities, or to raise export receipts. These attempts based on various commodity agreements have met with limited success. More attention has been paid to the alternative market solutions to this problem as international action even among producers has proven ineffective. Futures market is an obvious choice since well organized futures markets exist for most of the primary commodities. The present study investigated the potential of futures markets as a means of obtaining lower variance in revenue using the data from cocoa markets in London and New York. Data for four representative cocoa producers were analysed to develop strategies that reduce the variance in revenue. Two hedging strategies based on optimal hedge ratio concept and three selective strategies were tested for their ability to reduce risk and also to maintain the revenue trade-offs at a lower level. The analyses were carried out using two sample periods each 29 and 22 years long and tested in a 4 year data base outside the sample. The results confirmed that the producers facing both price and quantity risks in their production should only hedge a portion of their output. Adoption of a variance minimizing or utility maximizing hedges at a higher levels of risk aversion parameter as well as some selective strategies for hedging were found to give lower variance in revenue. There was always some trade-off associated with adopting these strategies. Selective strategies obtained a reduction in revenue with less trade-offs compared to optimizing strategies but were limited by the requirements of large cash outlays to meet the margin payments. For countries depending heavily on the revenue from cocoa hedges based on variance minimizing or utility maximizing strategies would be preferred over selective strategies. The ability to make good crop forecasts would greatly improve the success of hedging. / Master of Science

The cacao swollen shoot disease of Theobroma cacao L. (cacao) is caused by Cacao swollen shoot virus (CSSV; genus, Badnavirus, family, Caulimoviridae). The virus is endemic to West Africa, where it poses a serious threat to cocoa production. Despite efforts to control CSSV spread by replacement of infected trees with tolerant cultivars and mealybug vector management, the disease is widespread in West Africa. In Trinidad, leaf mosaic and vein-banding symptoms have been observed in cacao plants in the field since the 1940s, and recently at the International Cocoa Genebank (ICGT), a custodian of cacao germplasm resources. The strains A and B of the suspect Cacao Trinidad virus (CTV) caused the symptoms, and were thought to be related to CSSV, however, viral causality was not demonstrated, until now. To develop molecular detection methods for CSSV in infected plants, polymerase chain reaction (PCR) amplification of eight regions of the CSSV genome was implemented. The PCR results showed variable amplification frequencies of 19 - 42% at each region, for 124 isolates collected in Cote d'Ivoire and Ghana. Pairwise nucleotide (nt) analyses of the eight regions showed 66-99% shared identities, indicating that CSSV isolates exhibit extensive variability with respect to primer design. The results provided preliminary evidence for the existence of a CSSV complex consisting of four divergent species. The full length genome of 14 CSSV isolates from cacao determined using the Illumina HiSeq platform showed 70-99% shared nt identities. The pairwise nt identities placed CSSV sequences into a group of four distinct species, one of which represented a previously undescribed species. Moreover, the full-length genomes grouped phylogenetically with other badnaviruses and revealed two CSSV subclades with three types of genome arrangements; four, five or six open reading frames (ORFs). Predicted functional protein domains were conserved on each ORF. Two distinct, full-length genome sequences were determined using the Illumina HiSeq platform, from DNA isolated from cacao leaves exhibiting distinct symptoms in Trinidad. The sequences were validated by PCR-amplification and sequencing of overlapping viral genome fragments. Pairwise nt analysis indicated that each genome shared 52-62% nt identities with CSSV and other badnaviruses, suggesting that the two are distinct species. Phylogenetic analysis indicated that the two sequences are not strains of the same virus, as supposed, but they represent two previously undescribed species in the genus, Badnavirus, and they have been named Cacao mild mosaic virus (CaMMV) and Cacao yellow-vein-banding virus (CYVBV). Despite sharing the same host and causing similar symptoms in cacao, CSSV, CaMMV, and CYVBV are phylogenetically-distinct species. The discovery of a CSSV species complex and the identification of three new cacao-infecting badnavirus species will support the development of molecular detection tools using the partial and complete genome sequences determined in this study. The ability to develop validated molecular tools for the detection of CSSV and related viruses, CaMMV and CYVBV, in cacao will aid quarantine efforts and safe movement of germplasm from the ICGT in Trinidad to cacao-growing countries, worldwide. Also, molecular diagnostics tools are expected to be useful in efforts underway to develop CSSV-resistant planting material for countries in West Africa, which are currently experiencing continued or new disease outbreaks.

Master of Agribusiness / Department of Agricultural Economics / Vincent Amanor-Boadu / Despite the dependence of more than three-quarters of a million households depending on cocoa for their living in Ghana, the production segment of the cocoa industry is fraught with significant challenges manifesting as low farm productivity. Various intervention programs to help farmers improve productivity at the farm level have been used over the past few decades. One of such programs is the Cocoa Abrabopa Program (CAA), which uses an integrated approach where farmers are supplied inputs made up of fertilizer, pesticides and fungicides as well as provided training and extension support services. The inputs are provided on credit and the producers repay the cost of these inputs upon selling their crop. This study sought to assess the results of the CAA in enhancing the net profits of its members over time. It used survey data collected over five years from members of the CAA program. The study used an econometric model to evaluate the demographic and production characteristics of CAA members on their net profits. The results show that male members in the CAA program had higher net profits that their female counterparts, about GHS 237.32 more. For every year increase in the member’s age, the net income increased by GHS 6.46, which was statistically significant at the 10 percent level. The crux of the study – the effectiveness of the CAA program in enhancing performance – was supported by the results. Participants who were two years in the program posted GHS 591.13 more net profit than those who were in their first year. Those who were three year and four or more years posted respectively GHS 1,211.04 and GHS 18,752.29 than those in the first year. All these were statistically significant at the 1 percent level. Thus, the CAA program is producing what it is expected to produce – enhancing the net profits of its members and doing so in higher levels with the duration of membership. The study also found that having a bank account produced a higher effect on net profits than being male, posting GHS 296.13 more net profit than not having a bank account. The econometric model specified and estimated was significant and the variability in all the independent variables in the model explained about 46 percent of the variability in net profits. The study recommends that the CAA program incorporates helping all its members open bank accounts as part of its offerings. It also recommends working with policymakers and community leaders across its operational areas to encourage investments in the education of females and elimination of the tenural rights discrimination that frequently confronts females in agriculture. It also recommends that an increased effort be made to expand membership of the CAA program to all cocoa producers in Western South because of the significant benefit of the yield effect of the region on net profit of CAA members in the region.