En un contexto de economía circular, una completa valorización de residuos
procedentes de la industria agroalimentaria para convertirlos en productos de alto valor
añadido, minimiza los impactos ambientales y maximiza el uso de recursos renovables.
En este sentido, se propone la valorización integral del bagazo de cerveza (BSG), el
principal subproducto de la industria cervecera (85%), empleando tecnologías
emergentes respetuosas con el medio ambiente. Esta Tesis Doctoral propone el uso de
diferentes tecnologías verdes y eficientes para la recuperación de los compuestos
bioactivos del BSG, tales como la extracción con fluidos supercríticos y la extracción
asistida por ultrasonidos (UAE). Además, se ha propuesto el uso de agua subcrítica
(subW) para hidrolizar y fraccionar los componentes estructurales del BSG (fracciones
de lignocelulosa y proteínas), recuperando al mismo tiempo diferentes compuestos
bioactivos, tales como compuestos fenólicos, biopéptidos y aminoácidos, dentro de un
concepto de biorrefinería integrada.
The development of new strategies in the bioeconomy field aims to find alternatives to
fossil-based feedstocks for the production of fuels and chemicals, since the availability of
fossil resources is limited, and their use is associated with the global climate change.
Furthermore, waste generation is increasing exponentially, as consequence of the growing
population and higher quality of life. One of the most attractive alternatives to deal with
both problems is the development of sustainable biorefineries for processing biomass into
different products and energy, being key in the context of circular economy, closing loops
of streams, and valorizing multiple outputs, considering both, environmental and economic
aspects. In this sense, the integral conversion of lignocellulosic agro-industrial residual
biomass (second-generation biomass) into high value-added products minimizes
environmental impacts and maximizes the use of renewable resources.
In this work, an integral valorization of brewer´s spent grain (BSG) by using clean and
environmentally friendly technologies has been proposed. BSG is the main byproduct of the
brewing industry (85%). It is a lignocellulosic biomass with high protein content (10 - 30%,
w/w) and around 6% of lipids, being also a valuable source of phenolic compoundsthat have
demonstrated antioxidant effects. Based on its chemical composition, the integration of
BSG within a biorefinery concept is of great interest to obtain different high-value
biocompounds. However, due to the recalcitrant structure of lignocellulosic biomass, the
fractionation of these byproducts into their individual building blocks remains a challenge
for the optimal development of second-generation biorefineries.
