Produção de sucedâneos de cereais de pequeno-almoço ricos em compostos bioactivos

• Author(s): Fonseca, Margarida Cruz
• Date: 2011
• Persistent ID: http://hdl.handle.net/10400.5/4081
• Origin: Repositório da UTL
• Subject(s): breakfast cereals; extrusion cooking; dwells on tomato; chestnut flour; bioactive compounds
• Document Type: Master thesis
• Language: Portuguese
• Advisor(s): Barros, Sara Beirão da Costa Teixeira; Martins, Margarida Moldão
• Contributor(s): Repositório da Universidade de Lisboa

Description

Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia

The main goal of this paper was to produce breakfast cereal substitutes from undervalued materials (dwells on tomato and chestnut flour), full of extrusion-cooking bioactive compounds. In the first phase, there was a physicochemical characterization of raw materials to use, in order to verify the presence of bioactive compounds and to define the processing conditions. In the second phase, it was the production and characterization of the substitutes. The parameters of the process that were studied were mixture composition, temperature and extrusion spin speed of extrusion process. So, it was established na array of experimental design with the following limits of variation: temperature T2 T3 = 110-150ºC, 10-50% of the sample composition of dwells on tomato, with the remainder of chestnut flour, and spin speed of 100-204 rpm. The products obtained were evaluated for color, texture absorption capacity, microstructure and antioxidant activity. The results indicated that the characteristics of extruded depend on the processing temperature and composition of the mixture. Thus, the extruded with highest quantity of dwells were those who absorbed more milk, with low hardness and a lower rate of expansion. The antioxidant activity of the products obtained was maximized for intermediate concentrations (40/50%) of dwells on tomato and processing temperature (120 º to 140 º C). It can be concluded that it is possible to obtain extruded products, alternative to breakfast cereals from dwells on tomato and chestnut flour with antioxidant activity.