EFFECT OF DRYING BEET LEAVES ON THE EFFICIENCY OF EXTRACTION OF BIOACTIVE COMPOUNDS

CORREA DE CARVALHO MARCIA; JAGUS ROSA J; AGÜERO M. VICTORIA

Campinas

Congreso; slaca 2021. Impact of Food Science on Health and Disease; 2021

Ingenieria de alimentos UNICAMP

Beet (Beta vulgaris L. var. conditiva) is a commonly consumed vegetable. The root is usually consumed, while the leaves are discarded. Beet leaves (BLs) are a rich source of polyphenols and betalains, bioactives that have beneficial effects on health. One challenge associated with therecuperation of these compounds is related to the stabilization of the raw material in order to extend its shelf life providing time for processing. However, these processes, such as drying, could affect the extraction efficiency of bioactives compounds. Therefore, the aim of this research was to determine the impact of different drying configurations on the efficient extraction of bioactive compounds from BLs. Selected BLs were disinfected and placed in a chamber of 37°C, arranged in individual (IB), double (DB) and triple (TB) beds, with 6 leaves each. Weight was recorded until equilibrium and results were adjusted to kinetic models. Dry leaves were ground. The extraction was done in an ultrasonic bath (ratio 1:17, 15', 50°C). Extracts were centrifuged (10,000rpm, 10', 5°C) and the supernatant was stored. Betalains and total polyphenols were spectrophotometrically quantified and compared with an extraction carried out with fresh raw material (FRM). Weight loss fit an empirical model, with R2 higher than 0,99 for the three beds configurations. The final moisture of samples resulted in 10,4%. The drying was favorable for Polyphenols extraction showing significant differences among beds with an increase of 84, 99 and 56% for IB, DB and TB related to FRM. For Betaxanthins, the behavior was similar, DB presented the highest content, with an increase of 25% related to the FRM. Conversely, FRM presented a higher content of Betacyanins (0.057mg/g) while there were recoveries of 89, 77 and 44% for IB, DB and TB respectively. The drying process made it possible to stabilize the raw material and improve extraction yields.