
handle: 20.500.11960/2673
Mestrado em Engenharia Alimentar na Escola Superior de Tecnologia e Gest?o do Instituto Polit?cnico de Viana do Castelo Atualmente, e cada vez mais, os consumidores exigem produtos com maior tempo de prateleira, convenientes, dando prefer?ncia a produtos naturais, em detrimento dos elaborados com aditivos qu?micos. Como alternativa ao uso de aditivos alimentares artificiais, diversos compostos bioativos presentes em diferentes esp?cies vegetais passaram a ser considerados pela ind?stria alimentar, principalmente devido ?s atividades antimicrobiana e antioxidante, requisitos essenciais para uma conserva??o mais natural. A empresa acolhedora do presente est?gio ? uma empresa exportadora de produtos c?rneos tradicionais curados, do tipo pronto-a-comer, que procura inovar e, simultaneamente, aumentar o tempo de vida ?til dos seus produtos. No ?mbito deste est?gio, surgiu uma ideia de projeto, com o apoio da Escola Superior de Tecnologia e Gest?o - Instituto Polit?cnico de Viana do Castelo, que consistia em extrair compostos de interesse da casca de pinheiro-bravo, que pudessem atuar principalmente como agentes antioxidantes, aumentando o tempo de vida de prateleira dos produtos da empresa. O pinheiro-bravo, Pinus pinaster Aiton subsp. atlantica, ? uma ?rvore muito abundante no nosso pa?s, podendo ser encontrada ao longo de todo o territ?rio, sendo o principal objetivo da sua planta??o a explora??o da madeira para diversos fins industriais, designadamente no fabrico de papel, como material de constru??o ou para mobili?rio. A casca do pinheiro-bravo tamb?m se tornou um produto com bastante interesse como combust?vel no fabrico de pellets. Recentemente, devido ? sua riqueza em polifen?is e polissacar?deos, que correspondem a cerca de 50 a 60% da massa da casca, tem vindo a suscitar o interesse por parte da ind?stria farmac?utica para aplica??o em produtos cosm?ticos, fins medicinais como suplemento alimentar e, ainda, como aditivo alimentar. O objetivo deste trabalho foi a obten??o de extratos da casca de pinheiro-bravo (Pinus pinaster) para futura aplica??o em produtos c?rneos fumados na empresa onde decorreu o est?gio. Assim, foram analisados os produtos curados a testar tendo sido selecionados a ?Chouri?a de carne? e a ?Barriga?. Foram identificadas as etapas da produ??o que melhor se adequavam ? adi??o do extrato e determinadas as quantidades de produto necess?rias bem como a quantidade de extrato a adicionar em fun??o das propriedades antioxidantes e das amostragens a considerar para as subsequentes an?lises necess?rias ao estudo dos tempos de vida dos produtos funcionalizados. A extra??o dos compostos da casca de pinheiro, pela t?cnica de microondas, foi efetuada em dois ensaios distintos, e foram testados tr?s tipos de solventes, designadamente ?gua, ?gua+etanol (50:50, vol/vol) e etanol. Foram avaliados os par?metros, rendimento da extra??o, teor de compostos fen?licos totais dos extratos e determinada ? atividade antioxidante por dois m?todos distintos, DPPH (2,2-difenil-1-picrilhidrazilo) e ABTS (2,2?-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid). Em qualquer dos ensaios o rendimento de extra??o foi superior no etanol, seguido da mistura hidroetan?lica e por ?ltimo da ?gua. No caso do teor de fen?licos totais, n?o foram detetadas diferen?as significativas no 1? ensaio de extra??o, mas no 2? ensaio as diferen?as entre os solventes etanol e a mistura hidroetan?lica foram significativas. Em ambos os ensaios a ?gua foi o pior solvente no respeitante ao teor de fen?licos totais dos extratos. Na determina??o da atividade antioxidante pelo m?todo DPPH, n?o existem diferen?as significativas entre os solventes etanol e a mistura hidroetan?lica em ambos os ensaios de extra??o, pelo m?todo de ABTS existem diferen?as significativas entre os solventes etanol e a mistura hidroetan?lica, apenas no 1? ensaio de extra??o. Em ambos os m?todos, foram detetadas diferen?as significativas entre os extratos aquosos relativamente aos outros dois. Nowadays, and increasingly, consumers demand products, convenient and with longer shelf life giving preference to natural products, in preference to those using chemical additives. As an alternative to the use of artificial food additives, many bioactive compounds from different plant species are now considered by the food industry, mainly due to their antimicrobial and antioxidant activities, essential requirements for a more natural conservation. The company where this internship took place is an exporter of traditional cured meat products, ready-to-eat, which seeks to innovate and, at the same time, increase the shelf life of its products. Within this internship, a project idea emerged, together with the Escola Superior de Tecnologia e Gest?o - Instituto Polit?cnico de Viana do Castelo, which consisted of extracting compounds of interest from maritime pine bark, which could act mainly as antioxidant agents, increasing the shelf life of the company's products. The maritime pine, Pinus pinaster Aiton subsp. atlantica, is a very abundant tree in our country and can be found throughout the entire territory, with the main objective of its plantation being the exploitation of wood for various industrial purposes, namely in the manufacture of paper, as construction material or for furniture. Pinus pinaster bark has also become a product of great interest as a fuel in the manufacture of pellets. Recently, due to its richness in polyphenols and polysaccharides, which correspond to about 50 to 60% of the mass of the bark, it has been arousing the interest of the pharmaceutical industry for application in cosmetic products, medicinal purposes as a food supplement and, even, as a food additive. The purpose of this work was to obtain extracts of Pinus pinaster bark for future application in cured-smoked products. Thus, the products to be tested were analyzed and a pork sausage-like product ?Chouri?a de carne? and smoked pork belly were selected for further application of bark extracts. Also, the production steps of those products better adjusted to extract addition were selected and the amount of extract to be added were also determined according to the desired antioxidant properties and sampling to be considered for subsequent analysis necessary to the study of products shelf life The extraction of pine bark compounds was carried out using the microwave technique with three different solvents, water, water+ethanol (50:50, v/v) and ethanol. The extraction yield, the total phenolics content and the antioxidant activity of each extract were also determined. Different parameters were evaluated, extraction yield, content of total phenolic compounds in the extracts and the antioxidant activity by two different methods, DPPH (2,2-diphenyl-1-picrilhidrazilo) and ABTS (2,2?-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid). In any of the tests, the extraction yield was higher in ethanol, followed by the hydroethanolic mixture and finally by water. In the case of the total phenolic content, no significant differences were detected in the first extraction test, but in the second test the differences between the ethanol solvents and the hydroethanolic mixture were significant. In both tests, water was the worst solvent in terms of the total phenolic content of the extracts. In the determination of antioxidant activity by the DPPH method, there are no significant differences between the ethanol solvents and the hydroethanolic mixture in both extraction tests, on the ABTS method there are significant differences between the ethanol solvents and the hydroethanolic mixture, only in the first extraction test. In both methods, significant differences were detected between the aqueous extracts in relation to the other two.
Atividade antioxidante, Compostos fen?licos, Shelf life, Pinus pinaster, Microwave extraction, Phenolic compounds, Extra??o microondas, Smoked meat products, Antioxidant activity, Atlantic pine cortex, Produtos c?rneos fumados, C?rtex de pinheiro-bravo, Tempo de vida ?til
Atividade antioxidante, Compostos fen?licos, Shelf life, Pinus pinaster, Microwave extraction, Phenolic compounds, Extra??o microondas, Smoked meat products, Antioxidant activity, Atlantic pine cortex, Produtos c?rneos fumados, C?rtex de pinheiro-bravo, Tempo de vida ?til
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