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Previous issue date: 2013-05-06 / Brazil is a big producer and exporter of fruits and fruit juice. The sale, in many cases, is limited to the seasonality of production and perishability of fruits. The Brazilian cherry is a tropical fruit originally from the South and Southeast regions of Brazil, with high perishability and susceptibility to physical damage during transport. Considering all the losses that the productive chain of fresh Brazilian cherry may suffer, it is evident the importance of producing the juice of this fruit. Traditionally, thermal treatment has been employed in the processing and preservation of these products; however, undesirable changes in sensory and nutritional characteristics can happen. Among the innovative technologies to reduce these undesirable changes is High Hydrostatic Pressure (APH). This method of food preservation provides additional benefits to the product allowing products closer to the fresh product. This study aimed to investigate the process of high pressure in the preservation of Brazilian cherry pulp (Eugenia uniflora L.) to assess their microbiological safety and sensory quality and nutritional nectar obtained. The study was conducted at Embrapa Food Technology (Rio de Janeiro-RJ, Brazil). The Brazilian cherry pulp was processed by high hydrostatic pressure using different pressure levels, temperatures and retention time, following a central composite design. Microbiological analyzes were performed (for Salmonella spp., Coliforms at 45? C, mesophilic aerobic, yeasts and molds), physico-chemical (pH, acidity, soluble solids, fibers), antioxidant activity and instrumental color. It was investigated nectar microbiological shelf life obtained from the pressurized pulp. Shelf life estimation through Survival Analysis was also carried out, and the nectar exceeded 35 days of storage. Further studies are recommended. The sensory characteristics of nectars obtained from the pressurized pulp, non-pressurized pulp (Control), pasteurized Control, and three commercial brands available in the market were evaluated by consumer acceptance and through the methodology check all that apply (CATA). Data were analyzed using analysis of variance, Tukey test, and Multiple Factor Analysis. The high pressure process has been effective in preserving the nectar refrigerated for up to 35 days. There was no significant negative effect on antioxidant activity and color of the samples subjected to high pressure. The results obtained in the determination of "ideal" pulp concentration and sweetness for the nectar formulation cherry were 36% and 10%, respectively. In Acceptance Test samples pressurized and commercial B had the highest scores and the terms most frequently used in the methodology check all that apply were reddish, cherry flavor, presence of particles, attractive color, acid, astringent, off-flavor, sweet, bitter, gritty look. Such terms are therefore considered the most suitable to describe the samples by consumers. / O Brasil ? um grande produtor e exportador de frutas e suco de frutas. A comercializa??o, em muitos casos, ? limitada ? sazonalidade da produ??o e ? perecibilidade das frutas. A pitanga ? uma fruta tropical origin?ria das regi?es Sul e Sudeste do Brasil, com alta perecibilidade e susceptibilidade a danos f?sicos durante o transporte. Tendo em vista todas as perdas que a cadeia produtiva da pitanga in natura pode sofrer, fica evidente a relev?ncia da obten??o do suco deste fruto. Tradicionalmente o tratamento t?rmico tem sido empregado no processamento e conserva??o destes produtos; no entanto, altera??es indesej?veis nas caracter?sticas nutricionais e sensoriais podem acontecer. Entre as tecnologias inovadoras para redu??o dessas altera??es indesej?veis, est? a Alta Press?o Hidrost?tica (APH). Este m?todo de conserva??o de alimentos oferece benef?cios adicionais ao produto permitindo a obten??o com caracter?sticas mais pr?ximas do produto in natura. Este estudo teve como objetivo investigar o processo de alta press?o na conserva??o de polpa de pitanga (Eugenia uniflora L.) de modo a avaliar a seguran?a microbiol?gica e a qualidade sensorial e nutricional do n?ctar obtido. O trabalho foi realizado na Embrapa Agroind?stria de Alimentos (Rio de Janeiro, RJ, Brasil). A polpa de pitanga foi processada por alta press?o hidrost?tica utilizando diferentes n?veis de press?o e tempo de reten??o, seguindo delineamento experimental do tipo composto central. Foram realizadas an?lises microbiol?gicas (para Salmonella spp., coliformes ? 45?C, aer?bios mes?filos e fungos filamentosos e leveduras), f?sico-qu?micas (pH, acidez, s?lidos sol?veis, fibras), atividade antioxidante, cor instrumental e avalia??o sensorial. Foi avaliada a vida ?til microbiol?gica do n?ctar obtido a partir da polpa pressurizada e sensorialmente atrav?s da an?lise de sobreviv?ncia (Survival Analysis). O n?ctar apresentou vida ?til superior a 35 dias, necessitando estudos subsequentes. As caracter?sticas sensoriais dos n?ctares obtidos a partir da polpa pressurizada, da polpa n?o pressurizada (controle), do controle pasteurizado e de tr?s marcas comerciais dispon?veis no mercado foram avaliadas atrav?s da aceita??o do consumidor e utilizando a metodologia check all that apply (CATA). Os dados foram analisados por An?lise de Vari?ncia, teste de m?dia, e An?lise M?ltipla de Fatores. O processamento da polpa por alta press?o foi eficaz na preserva??o do n?ctar refrigerado por at? 35 dias. N?o houve efeito negativo da APH na atividade antioxidante das amostras. Nas an?lises de cor todos os par?metros analisados (L*, a* e b*) diferiram (p<0,05) do controle (polpa n?o pressurizada) e as amostras pressurizadas. Os resultados obtidos na determina??o de concentra??o de polpa e do?ura ?ideais? para a formula??o do n?ctar de pitanga foram 36% e 10%, respectivamente. No Teste de Aceita??o as amostras pressurizada e comercial B obtiveram as maiores m?dias e na metodologia check all that apply, os termos utilizados mais frequentemente como descritores foram cor avermelhada, sabor de pitanga, presen?a de part?culas, cor atrativa, ?cido, adstringente, sabor estranho, gosto doce, gosto amargo, aspecto arenoso. Tais termos podem ser, portanto, considerados os mais apropriados na descri??o das amostras pelos consumidores.
| Identifer | oai:union.ndltd.org:IBICT/oai:localhost:jspui/2496 |
| Date | 06 May 2013 |
| Creators | FERREIRA, Ellen Almeida dos Santos |
| Contributors | Deliza, Rosires, Rosenthal, Amauri, Deliza, Rosires, Meleiro, Cristiane Hess de Azevedo, Melo, Lauro Lu?s Martins Medeiros de |
| Publisher | Universidade Federal Rural do Rio de Janeiro, Programa de P?s-Gradua??o em Ci?ncias e Tecnologia de Alimentos, UFRRJ, Brasil, Instituto de Tecnologia |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da UFRRJ, instname:Universidade Federal Rural do Rio de Janeiro, instacron:UFRRJ |
| Rights | info:eu-repo/semantics/openAccess |
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