Valorization of immature wasted tomatoes to innovative fermented functional foods

• Autor(a) principal: Farrokhi, Mahsa
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.1/19371
• topic: Bactérias do ácido láctico; Fermentação láctica; Lactiplantibacillus plantarum; Weissella paramesenteroides; Potencial probiótico; Desenvolvimento de novos produtos; Domínio/Área Científica::Ciências Sociais::Outras Ciências Sociais

This study aimed to consolidate a strategy to valorise immature tomato fruit (GT, cv. H1015) through controlled fermentation (use of starter cultures) in producing high-value food products to support circular economy-oriented innovation. The probiotic character of two pure LAB strains, Lactiplantibacillus plantarum (LAB97, isolated from GT) and Weissella paramesenteroides (C1090, INIAV collection), were tested using static in vitro gastrointestinal digestion model (sequential digestion and digestive enzymes). Both LAB strain counts reached ca. 6 log CFU/ml after the in vitro simulation, meeting the viability criterion for potential probiotic capacity. In the evaluation of GT-controlled fermentation, the two starters (per se) and the addition of NaCl (1.5%) were assessed (108 CFU/ml of inoculum, 100 rpm, 20 °C, 14 days). It was concluded that LAB 97 strain was superior to the C1090 strain or spontaneous fermentation because it increased process efficiency (fast acidification) and developed an ingredient with sensory acceptance and probiotic potential (> 7 log CFU/ml). The second approach aimed to evaluate the formulation of a sauce with sensory, nutritional, and probiotic potential based on the combination of fermented GT (LAB 97) with other valuable ingredients (avocado, parsley, and honey). The formula chosen included fermented GT (65%) and a 4:2:1 mixture of these ingredients. Different technological strategies (thermal treatment and non-treatment) were tested to prevent microbial contamination by the additional ingredients and promote the shelf life of the sauce storage. The sauce’s shelf stability samples were evaluated during storage (5 °C, 21 days) concerning several quality attributes (microbial counts, pH, soluble solids content, CIELab, total phenolic content, and antioxidant activity and panel sensory analysis). The viability of a sauce prototype with sensory quality and valuable antioxidant composition, meeting the microbiological criteria for this type of product, could be concluded. However, decontamination treatments do not improve sauce stability compared to raw ingredients.