Desenvolvimento de Smoothie fermentado por microorganismos da Komucha com base no perfil de consumo, composição química, compostos bioativos e descrição sensorial

Abstract

Sensoriality, well-being and practicality are characteristics desired by healthy drink consumers. Therefore, the development of a smoothie with these characteristics demands planning and analyses that systematically check if the sensorial and functional qualities are aligned, in order to increase the chances of acceptance by consumers. In light of this, the aim of this research was to develop a protocol of production of a smoothie fermented by kombucha microorganisms based on consumption profile, chemical composition, bioactive compounds and sensorial description. This research was underpinned in two distinct parts. In the first phase, the smoothies were characterized in the Brazilian market, which was sub-divided into three parts: [1] previous research on the profile of smoothies’ consumers; [2] sensorial analysis and [3] physicochemical and instrumental characterization of the main smoothies sold in the Brazilian market. The information collected in the first phase guided the second phase, in which the base fruits and other ingredients that should be used in the experimental planning of the mixtures were defined. After the nutritional and sensorial definition of the best mixtures, they were inoculated with kombucha. The results identified that smoothies are beverages consumed by young women of a high social class residing in the south region of Brazil, and what encourages their consumption is the purpose of health and flavor. The beverages existing in the Brazilian market present various purposes and varied physicochemical composition. The values of pH (3.21 to 4.3), Brix level (10.1 to 18) and acidity (0.34 to 1.02 g/100 mL) presented significant differences. Glucose (1.4 to 4.80 g/100 mL), fructose (2.94 to 9.12 g/100 mL) and sucrose (1.69 to 5.23 g/100 mL) presented variations between 51 and 74% in the 17 commercial samples evaluated. Viscosity varied from 22 to 328 mPa.s. Smoothies composed by yellow fruit presented greater intensity of color, carotenoids and high antioxidant activity in relation to those composed by green or red fruit. The phenolic content varied from 612 to 1498 mg CAT/L. Chlorogenic acid (6.95 to 54.8 mg/L) and phlorizin (2.08 to 20.03 mg/L) were the phenolics in the highest concentration in all the samples. The beverages sensorially accepted are not the same as the ones that stood out in relation to the physicochemical aspect, which may have also influenced their diverse sensorial description. From the results of the first phase, it was possible to develop planned mixtures by planning and a simplex centroid, containing antioxidant ingredients, and being differentiated by the kombucha fermentation process. The fermentation for 15 hours at 28° C of the smoothies by the bacteria consortium present in the kombucha provided a viscosity 3.2 times lower (39.68 to 12.33 mPa.s), reduction of 13.3% in glucose (1.80 to 1.56 g/100 mL) and 16.11% in fructose (2.98 to 2.50 g/100 mL). Acidity was 27% higher (0.65 to 0.83 g/100 mL) and ascorbic acid 2.7 times higher (5.4 to 14.60 mg/L). Total phenols had an increase of 7.6 % (10758 to 11641 mg CAT/L). The content of epicatechin doubled (14.24 ± 0.51 to 29.80 ± 0.94 mg/L), of phloridzin was 1.4 times higher (2.92 to 4.17 mg/L) and of chlorogenic acid (40.92 to 43.96 mg/L) was 7% higher. The antioxidant activity of the unfermented beverage was higher than the fermented one in the four kinds of analyses of this activity. The physicochemical change in the fermented smoothie was confirmed, and this caused a great impact on its capacity to have antiglycemic activity up to 22.8% higher (IC50 = 68,90 mg/mL versus 80,61 mg/mL). Therefore, the fermentation allowed to highlight formulations that simultaneously presented a high antioxidant, antiglycemic and sensorial potential. As such, this research presents technical and scientific information for the development of smoothies directed to the expectation of the consumer market, that is, tasty, purposeful and innovative.