29 research outputs found
Uso sustentado e processamento de llex paraguariensis St. Hill (Erva-Mate).
The general objective of this thesis was to study the processing of maté Ilex paraguariensis St. Hil Lineage Cambona 4, a renewable natural resource of sustainable form of small farmers in the South of Brazil. An analysis becomes on the conception of the agricultural producers of the city of Machadinho-RS on environment and maté organic culture. A study of the mate processing is carried out initiating with the singeing, using units of laboratory, which consists one of the conventional stages in the maté processing. The contact time is determined to produce similar leaves to the ones of industrial processes. The best operational condition consisted of singeing per 5 minutes, operating the singer in the rotation of 80 rpm. The initial moisture content of maté leaves varied of 61,9 - 65.0% (db), and to the ending of singeing, under action of combustion gases GLP in the average temperature of 181oC, the moisture content it is reduced for 14,6% (db). The drying was carried out in vibrated tray drier, at the operations conditions: air flow in the temperature and velocity of 60oC and 0,64 m/s; amplitude and frequency of vibration, 0.5,10-3 m and 183 m rd/s, being Aù.2/g equal to 1,7; average specific area initial of maté leaves processed was 52,63 cm2/g. The convective coefficients of heat transfer had been quantified, in the operations of singeing and drying, being obtained the average values, 0,316 at 0,606 and 0,097 kJ/m2.min.oC, respectively. The extraction studies of soluble had been carried through the use of two techniques. The first method, agitation and mixing of maté triturated water, was effected at the temperature of 90oC. It was quantified that 50.7% of solids in the maté dehydrated are constituted by soluble, that were extracted in multiple stages of leaching. In only stage 37.1% of solids are extracted. The second method, with fixed bed of triturated maté, it was used an extractor with perforated chamber for draining of the extract. The experiments had been carried out with multiple extractions, each one with new amount of solvent. In only extraction, 35.5% of solids are extracted. The extract presented a solid concentration of 3,4 to 4,5%. Arabic gum was added to the extract in the concentrations of 0, 0,2; 0,4; 0,6; 0,8; 1,0; 1,5 and 2.0%, in relation to it solids content. The mixtures had been affected with the objective to study the influence of the Arabic gum in the drying and the flavor of drinks. The extracts had been processed in spray dryer at the average operations conditions: temperature and flow air: 190oC and 32.1 m3/h; extract feed at 340 mL/h. The moisture content of powder had varied from 1,8 to 6,6% (db). Sensorial analysis was carried out with three formulations at the concentrations: 0; 0,2 and 1,0% of Arabic gum. To the experimental results a statistical treatment was applied and was verified best preference for the formulations with 0.2% of the Arabian gum content. This showed the influence of the encapsulating agent in the aroma retention. The Arabian gum facilitated the powder separation in the cyclone. Concentrated of soluble of maté they were lyophylisated and obtained the lyophilisation curve. A study of caffeine traced was carried out during the processing. The caffeine determinations were effectuate in the: natura mate; singed maté; dried maté after the singeing and powder maté obtained by spray dryer. The losses of caffeine had been of: 33,6% in singeing 40,7% after the drying in vibrated tray; 62,2% after the spray drying. With soluble extracts of maté of spray drying and lyophilisation new products were developed: Mateccino mate mixing with chocolate ; maté candy and suggestions of fine drinks with maté extract. The economic feasibility study of a plant with capacity for processing 1,500 kg maté leaves/h, it showed: the necessity of: annual fixed capital investment of R 800.322,00; that the total income is of R 711.678,00.O objetivo geral desta tese foi estudar o processamento de Erva-Mate Ilex paraguariensis St. Hil Progênie Cambona 4, um recurso natural renovável de forma sustentável para pequenos produtores rurais no Sul do Brasil. Fez-se uma análise sobre a concepção dos produtores rurais do município de Machadinho-RS sobre meio ambiente e cultivo orgânico de erva-mate. Fez-se um estudo do processamento de erva-mate iniciando com o sapeco, utilizando unidades de laboratório, o qual consiste em uma das etapas convencionais no processamento de erva-mate. Determina-se o tempo de contato para produzir folhas similares às de processos industriais. A melhor condição operacional consistiu no sapeco por 5 minutos, operando o sapecador na rotação de 80 rpm. O conteúdo de umidade inicial das folhas de erva-mate variou de 61,9 a 65,0% (bu), e ao término do sapeco, sob ação de gases de combustão de GLP na temperatura média de 181oC, o conteúdo de umidade se reduziu para 14,6% (bu). A secagem foi efetuada em secador de bandeja vibrada, nas condições de operação: ar escoando na temperatura e velocidade de 66oC e 0,64 m/s; amplitude e freqüência de vibração, 0,5.10-3 m e 183 rd/s, sendo Aù2/g igual a 1,7; área específica média inicial das folhas de erva-mate processadas de 52,63 cm2/g. Foram quantificados os coeficientes convectivos de transferência de calor, nas operações de sapeco e de secagem, obtendo-se os valores médios, 0,316 a 0,606 e 0,097 kJ/m2.min.oC, respectivamente. Os estudos de extração de solúveis foram realizados com utilização de duas técnicas. Na primeira, efetuou-se agitação e mistura de erva-mate triturada, com água na temperatura de 90oC. Quantificou-se que 50,7% dos sólidos da erva-mate desidratada são constituídos por solúveis, que foram extraídos em múltiplas etapas de lixiviação. Em única etapa são extraídos 37,1% dos sólidos. Na segunda, com leito fixo de erva-mate triturada, utilizou-se um extrator com câmara perfurada para escoamento do extrato. Os ensaios foram realizados com extrações múltiplas, cada uma com nova quantidade de solvente. Em extração única, foram extraídos 35,5% dos sólidos. O extrato obtido apresentou uma concentração de sólidos de 3,4 a 4,5%. Ao extrato foi adicionada goma arábica nas concentrações de 0; 0,2; 0,4; 0,6; 0,8; 1,0; 1,5 e 2,0%, em relação aos sólidos contidos no mesmo. As misturas foram efetuadas com o objetivo de estudar a influência da goma arábica na secagem e no sabor das bebidas. Os extratos foram processados em secador por atomização nas condições operacionais médias: temperatura e vazão do ar: 190oC e 32,1 m3/h; alimentação de extrato a 340 mL/h. Os conteúdos de umidade do pó obtido variaram de 1,8 a 6,6%(bu). Efetuou-se análise sensorial de três formulações com concentrações: 0; 0,2 e 1,0% de goma arábica. Aos resultados experimentais aplicou-se tratamento estatístico e verificou-se maior preferência pela formulação contendo 0,2% de goma arábica, o que mostrou a influência do agente encapsulante na retenção de aromas. A goma arábica facilitou a captação do pó de erva-mate pelo ciclone do secador por atomização. Concentrados de solúveis de erva-mate foram liofilizados e determinou-se a curva de liofilização. Fez-se um estudo de rastreabilidade da cafeína, durante o processamento. As determinações de cafeína foram efetuadas em erva-mate in natura, sapecada, seguida de secagem e do extrato de erva-mate em pó obtido por spray dryer . As perdas acumuladas de cafeína foram de: 33,6% no sapeco; 40,7% após a secagem em bandeja vibrada; 62,2% após a secagem por atomização. Com os extratos solúveis de erva-mate secos por atomização e liofilização desenvolveram-se novos produtos: Mateccino achocolatado de erva-mate; balas de erva-mate e sugestões de drinks finos com percolado de erva-mate. O estudo de viabilidade econômica de uma planta com capacidade para processamento de 1.500 kg erva-mate/h, mostrou a necessidade de um capital de investimento fixo total de R 800.322,00; que a receita bruta é de R
711.678,00
Conservation unit and water quality: the influence of environmental integrity on benthic macroinvertebrate assemblages
AIM: This study aimed to determine the effectiveness of a Conservation Unit (CU) in maintaining the quality of freshwater habitats and to evaluate the influence of environmental integrity on benthic macroinvertebrate assemblages. METHODS: The research was conducted at sampling sites located within and outside of the CU in the Alto Uruguai region, southern Brazil, and included two stages: (i) the collection of benthic macroinvertebrates and (ii) the application of a Rapid Assessment Protocol (RAP) to characterise the habitat quality. RESULTS: A total of 1,362 benthic macroinvertebrates were collected during the study, totalling 30 taxa. The densities within and outside the CU were significantly different (F= 160.08; p= 0.05), and the Shannon diversity and taxa richness followed the same pattern (F= 118.72, p= 0.05; and F= 176.33, p= 0.04, respectively). In contrast, the Pielou equitability did not differ within and outside the CU (F= 0.19, p= 0.74). The biotic index (Biological Monitoring Working Party) indicated that water quality was good or very good in the majority of cases. Most of the sampling sites were classified as ‘natural’ according to the RAP. The taxa richness was significantly related to habitat diversity (F= 7.24; p = 0.05), but no significant relationship was found between the habitat diversity and the Shannon diversity (F= 2.13, p = 0.22). CONCLUSION: The CU was effective for the conservation of water quality and the freshwater biodiversity of benthic macroinvertebrates. The results show that the environmental integrity was related to the distribution of benthic macroinvertebrates, primarily to the taxa richness. More detailed investigations need to be developed to better understand these relationships and to take into account the temporal scale. An analysis of the most significant sources of stress on the aquatic life outside the area is recommended