OLIVEIRA, M. N.; http://lattes.cnpq.br/0390096594541555; OLIVEIRA, Marcela Nobre.
Abstract:
The production and consumption of lime and soursop in Brazil is very large, the main forms
of consumption are fresh and processed, therefore, a large amount of waste with high
nutritional value is wasted. Thus, the use of these residues to manufacture new products is
important. With this, this research aimed to dry discarded seeds of lime and soursop and to
process to obtain flour. The seeds of ata and graviola were dried in a convective dryer at
temperatures of 50, 60 and 70 °C at a speed of 1.5 m/s, crushed and transformed into flour.
The seeds and flours were evaluated for physical-chemical parameters, phytochemical,
physical and technological compounds. The drying kinetics were performed with monitoring
of water loss in a convective dryer with drying air speed 1.5 m/s and adjustments were made
with nine predicted drying models, determining the effective diffusivity, thermodynamic
properties and the hygroscopicity of the flours . The water adsorption isotherms were
determined using Aqualab, by the indirect static method, at a temperature of 25 °C. In
minutes and graviola flours at 70 °C, antioxidant activity, identification and quantification
of phenolic compounds, colorimetric analysis, mineral profile and adsorption isotherm were
evaluated using Aqualab, by the indirect static method, at temperatures of 20, 30 and 40 ° C.
Ata seeds stood out with higher levels of total sugars and soursop seeds showed higher levels
of starch, lipids, proteins, ascorbic acid and total phenolic compounds. Minute seed flours
showed higher levels of proteins, lipids, phenolic compounds and tannins; the soursop seed
flours contained a greater amount of starch. The fluidity of the flours evaluated using the
Hausner Factor and the Carr Index were better in the seed flours of the two species obtained
at 50 °C. Soursop seed flour showed greater wettability, whereas minutes seed flour had
greater emulsion activity and gelation capacity. With the drying kinetics data, it was found
that the best results were found in the Exponential and Exponential Two-Term Logarithmic
models. The effective diffusivities varied between 0.85 and 2.71 × 10-9 m2/s, with a
minimum value in the minutes and maximum in the graviola seeds, depending on the drying
temperature well described by the Arrhenius relation. The thermodynamic properties showed
a reduction in enthalpy and entropy and increases in Gibbs free energy. Flours from the seeds
of ata and soursop were classified as non-hygroscopic. As for the physical characteristics of
the seeds, it was found that the soursop seeds showed greater mass and greater circularity
and sphericity; the minute seeds showed higher specific and real masses. As for the
adsorption isotherms at a temperature of 25 °C, the flours were classified as type II and,
among the adjusted models, the GAB model presented the best adjustment parameter. Ata
seed flour has a greater antioxidant activity and a greater amount of minerals. Soursop seed
flour, on the other hand, had a higher amount of phenolic compounds. Flours are found in
the yellow region. Regarding the adsorption isotherms at temperatures 20, 30 and 40 °C, it
was found that the model proposed by GAB was the one that best fit for the flours of seed
of lime and graviola.