Fruit of Mandacaru: Kinetics of Drying and Physical-Chemical Characterization

The drying of the mandacaru fruit consists in an alternative way to reduce loss during its harvest and therefore minimizes its waste. The objective of this study was to physicochemically characterize the mandacaru fruit both fresh and dehydrated in an air circulation oven using three drying temperatures (40, 50 and 60 ºC), related to the water content, water activity, pH, acidity and phenolic compounds. Three empirical mathematical models were used to describe the drying (Henderson and Pabis, Midilli and Page). The Midilli's model had the best statistical indicators, fitting better to the experimental data. The fresh fruit showed water content of 82.75%, water activity of 0.986, titratable acidity of 0.18%, pH of 4.35 and phenolic compounds of 28.35 mg.100-1g. The parameters luminosity (L), intensity of red (+a), yellow intensity (+b), hue angle (hº) and chromaticity (C*) were respectively equal to 59.84±0.08; 5.72±0.06; 89.25±0.08; 5.72±0.06. The physicochemical compounds of the fruit were influenced by the drying, in which water content was 10.83, 8.31 and 7.56%, and the water activity was 3.99. 3.24 and 2.40 for the temperatures of 40, 50 and 60 ºC, respectively. The highest temperature caused a greater removal of water in the product along the drying. The dried mandacaru pulp showed titratable acidity of 0.41, 4.86 and 4.98%, pH of 4.76, 4.86 and 4.98 and phenolic compounds of 252.26, 156.53 and 196.10 mg.100-1g, and the parameters L (19.72, 23.41 and 26.15), a* (3.13, 1.31 and 1.30), b* (7.31, 6.53 and 9.14), H* (66.79, 78.69 and 81.92) and C* (7.95, 6.95 and 9.23) at the temperatures of 40, 50 and 60 ºC, respectively. The results of the characterization suggest the technological exploitation of the dried mandacaru fruit to add nutritional value to other foods or in the development of new products.