DEFESA DE DISSERTAÇÃO – USE OF DIFFERENT HYDROCOLOIDS FOR THE PRODUCTION OF A MIXED LEATHER FROM AÇAÍ, BANANA, PEANUT, AND GUARANA SYRUP
Data da publicação: 1 de março de 2021 Categoria: Sem categoriaData: 01/03/2021 – 08:00 horas –
Autor(a): KAMILA DE LIMA SANTOS
Banca Examinadora:
Profª. Lucicléia Barros de Vasconcelos Torres – orientadora – UFC
Prof. Paulo Henrique Machado de Sousa – co-orientador – UFC
Profº. Elenilson de Godoy Alves Filho – UFC
Profª. Alessandra Lopes de Oliveira – USP
Profº. Mário Eduardo Rangel Moreira Cavalcanti-mata – UFCG
Local: VIDEOCONFERÊNCIA – Conforme Portaria CAPES 36 de 19 de março de 2020.
Assista online – Para requerer o link para assistir a defesa de dissertação online como ouvinte (PROIBIDO MANIFESTAÇÃO – manter câmara e microfone desligados), você deve enviar e-mail para ppgcta@ufc.br até 04 horas antes do evento.Resumo:
This work aims to develop mixed leather from açaí, banana, peanut, and guarana syrup with added agar and gellan gum. Five mixed leather formulations were prepared with the addition of hydrocolloid agar and gellan gum: 1% agar (A1), 1% gellan gum (G1), 0.5% agar and 0.5% gellan gum (A050/G050), 0.25% agar and 0.75% gellan gum (A025/G075), 0.75% agar and 0.25% gum (A075/G025). Drying kinetics was performed with the five mixed leather formulations developed, and the mathematical models of Page, Newton, Logarithmic, and Henderson and Pabis were adjusted to the experimental data. Then, an entirely randomized experimental design (DIC) was used, keeping the temperature (60 °C) and drying time (8h) fixed and varying the hydrocolloid concentration (mentioned above) to choose the most promising formulations through the moisture, texture, total phenolic compounds (TPC), and total antioxidant activity (TAA) variables response. As a result, the Logarithmic model is
suggested as the most appropriate for all mixed leather formulations, as it presented a higher determination coefficient (99.79 < R2 < 99.99), lower values of the root mean square error (0.005<RMSE<0.018), and chi-square (0.000023<χ2<0.000339). It was found that hydrocolloids do not influence the dynamics of the drying process. Considering the lowest moisture value, the highest texture value, and the TAA, it is concluded that the mixed leather A050/G050, A075/G025, and A1 were chosen as the most promising preparations. Then, they were characterized according to their physical, chemical, physicochemical, and hygroscopic properties. The dietary fiber showed significant differences with the addition of 0.5% agar. The addition of 0.75% of agar presents a higher average for available carbohydrates (56.85 mg 100 g-1). Mixed leather was represented by larger quantities of K, Mg, and Na. The most negative effect of the in vitro digestion of the TPC, ABTS, and FRAP was determined
in the case of A050/G050. For rupture strength, sample A1 showed the lowest value (2.42 N) among mixed leathers. The drying process contributed to the concentration of some physicochemical parameters of a mixed leather that caused the shrinkage of the polymeric network of agar and gellan gum, resulting in a more compact mixed leather. In turn, this polymeric net trapped the lipid content and the TPC (after gastrointestinal digestion) of mixed leather A1, thus bringing beneficial effects to the body. The addition of agar and gellan gum in mixed leather in the proportions used in this work did not show any significant difference (p>0.05) for hygroscopicity and solubility. Henderson is model adjusted better to the mixed leather experimental data at the temperatures considered, simulating the food distribution chain in temperature conditions. Based on the results obtained, it is possible to develop mixed leather from açaí, banana, peanut, and guarana syrup added with agar and gellan gum
that meets consumers is demands looking for practical and nutritious food. Besides, the entire study supports the
understanding of the factors that may influence the final product: processing, drying, and stability.
Palavras-chaves: Ágar. Gellan gum. Drying.
