Almond bagasse as a source of bioactive compounds with antioxidant properties

The presence of components of nutritional interest makes fresh almond bagasse an interesting by-product for obtaining functional ingredients. Stabilization through a dehydration process is an interesting option for its integral use facilitating the conservation and management. Subsequently, it can be turned into powder facilitating its use as an ingredient. We determined the effect of hot air drying at 60 and 70ºC and lyophilization on the physico-chemical and functional properties of fresh almond bagasse, and the subsequent effects of in vitro digestion and colonic fermentation on the release of phenolic components and anti-radical capacity as well as on growing microbiota composition applying high throughput sequencing. The results obtained show that lyophilization gives rise to powder with a total phenol content and anti-radical capacity higher than hot air drying. Further, in all cases, both in vitro digestion and colonic fermentation provided a phenol content and anti-radical capacity superior to those existing in undigested products. In addition, after colonic fermentation, beneficial bacteria species have been identified. Obtaining powders from almond bagasse is presented as an interesting opportunity for the valorization of this by-product.