Banca de QUALIFICAÇÃO: CINTHIA MEIRELLY DE ARAÚJO ELPÍDIO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : CINTHIA MEIRELLY DE ARAÚJO ELPÍDIO
DATE: 28/08/2020
TIME: 14:30
LOCAL: VIRTUAL
TITLE:

Drying of the plum by the foam mat method

KEY WORDS:

plum, foam mat, optimization, physicochemical properties, bioactive compounds.

PAGES: 167
BIG AREA: Engenharias
AREA: Engenharia Química
SUMMARY:

Plum is a fruit characteristic of cold climates. In Brazil, its production is commonly carried out in the southeast and south of the country because of its mild climate. The consumption of this fruit can be very beneficial to human health since the plum is rich in bioactive compounds with high antioxidant capacity. However, the availability of this fruit is restricted to seasonality of production and low durability after harvest, requiring the application of techniques that prolong the shelf life of this food. Among the methods that can be applied is the foam mat drying that consists of the transformation of liquids or semi-liquids into a stable foam from the addition of a foaming agent and application of agitation so that there is the incorporation of air. In this work, the plum foam was produced from the addition of egg albumin and the drying was carried out in an air recirculation oven with a speed of 2 m/s. The study of the drying of the plum in a foam mat was divided into stages, the first part of which is the investigation of the effects of the process variables, whipping time and albumin concentration, on the physical, thermal properties and drying time in order to optimize the operational conditions for the production of the plum foam, whose values found were 3% albumin concentration and 12 minutes of whipping time. In the next step, the influence of temperature and foam mat thickness on the moisture, water activity and drying time of the plum foam was evaluated in order to define the best operational condition for drying this fruit, observing that the higher temperature and thinner foam mat are more suitable for the process. The last phase of this work investigated the influence of temperature on the physicochemical properties and bioactive compounds. The experiments were carried out using the foam in the previously optimized process condition (3% egg albumin in the formulation, 12 minutes of whipping and 0.8 cm layer thickness) and four drying temperatures: 50, 60, 70 and 80 °C. The analysis of the produced powders showed that the higher temperature (80 °C) provided a product with low cohesion between the particles and good fluidity, in addition to low absolute density (0.637 g/cm³), important characteristics for particulate materials. All powders showed good solubility and low water activity. The phenolic compounds were not affected by the process conditions, the antioxidant activity was favored by the temperature, but the amount of ascorbic acid and carotenoids was greatly reduced by the action of this variable. Based on the results, the condition that provided the best results for both the drying process and the quality of the plum powder was a temperature of 80 °C.

BANKING MEMBERS:
Presidente - 349802 - MARIA DE FATIMA DANTAS DE MEDEIROS
Interno - 1547970 - JACKSON ARAUJO DE OLIVEIRA
Externo ao Programa - 3652554 - FRANCISCO CANINDE DE SOUSA JUNIOR
Externa ao Programa - 029.669.684-60 - KATIA CRISTINA BORGES - UFRN
Externo à Instituição - MARCELLO MAIA DE ALMEIDA - UEPB