Valorization of figs (Ficus carica L.) for an extended shelf life

• Autor(a) principal: Amanze, Janet Omolayo
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.1/16817
• topic: Figo; Goma gelificada de figo; K-carragenato; Vida de prateleira; Qualidade; Domínio/Área Científica::Engenharia e Tecnologia::Outras Engenharias e Tecnologias

Fig fruit (Ficus carica L.) is an important food product of the Middle East, Mediterranean region and well appreciated by most elderly groups in Portugal, as the symbol of longevity. This study aims to develop two ways of adding value to highly perishable figs with no commercial acceptability, by accelerating fig drying with the use of a solar oven and producing a fig gum jelly which can be made available all year round with longer shelf life. A higher drying rate was observed with the blanched product in the solar oven dryer than in the direct solar drying. The optimization of the gum composition was carried out by using Response Surface Methodology (RSM) along with a mixture design, while the independent variables are: % fig paste, x1; % k-Carrageenan, x2 and % honey, x3. The sensory panel composed of 10 elements of both sexes evaluated nine (9) responses Y1 - Brilliance, Y2 - Transparency, Y3 - Aroma, Y4 - Texture A, Y5 -Texture C, Y6 - Sweetness A, Y7 - Sweetness B, Y8 - Mouthfeel and Y9 - Overall Opinion, originating nine polynomial models. Numerical optimization achieved the best fig gum jelly composition with: 55 % fig paste, 15 % k-carrageenan and 30 % honey. The validation of optimum product was achieved by the same panel and the panelists preference of the optimum formulation for all responses with 0.3 desirability was stunning. The shelf life of twenty-one days was achieved for unrefrigerated products while the refrigerated ones twenty-five days through microbiological analysis. The physicochemical analysis showed that the fig gum jelly contained a minimum amount of protein and minerals with low ash content. Also, the moisture and water activity were found to be lower in the fig gum jelly than in the fresh fig.