Resumo:
Passiflora cincinnata Mast. is a species commonly known as passion fruit and its cultivation is conducted by cooperatives formed by family farmers, with 24 agro-industries in the state of Bahia alone. It is known that food processing units generate large volumes of residual biomass after harvesting and processing. An efficient way of reuse would be through the use of fruit and vegetable peels from the food chain, to extract high-value bioactive molecules such as pectins, structural anionic heteropolysaccharides that have potential for application in numerous areas. Conventional or traditional pectin extraction methods have numerous limitations, such as: long processing time, high energy expenditure and solvent consumption. High-intensity ultrasound has been proposed as an interesting alternative for the extraction of pectin from agro-industrial residues, considering the need for the development of sustainable processes, lower energy expenditure and alignment with the principles of sustainability and inovação.Com this, the objective of this work was to develop and optimize a high-intensity ultrasound-assisted extraction process to obtain pectins from the peel of the passion fruit of the caatinga (Passiflora cincinnata Mast.). For this, preliminary tests were developed to determine the best solid-liquid ratio (SLR) and the sonication time, followed by statistical optimization using a central rotational composite design and response surface methodology. The maximum yield observed was approximately 10.7% low-methoxyl (LM) pectin after 15 minutes of sonication using a 1:30 SLR. After fixing these variables, further optimization and validation studies led to yields of approximately 7.5% high methoxyl (HM) pectin in a 75% duty cycle, ultrasound amplitude of 78%, and pH 1.9. The chemical and physical quality of the pectins, evaluated by the content of galacturonic acid (GalA) and instrumental color, showed that both the organic and inorganic acids tested produced HM with adequate color characteristics and GalA contents above 65%. Therefore, this study describes for the first time an optimized method of extracting and characterizing pectins obtained from Caatinga passion fruit by-products using ultrasound technology, demonstrating that this emerging technology can be an appropriate and sustainable approach for the valorization of unconventional substrates.
