Oil and protein extraction from fruit seed and kernel by-products using a one pot enzymatic-assisted mild extraction

•One-pot protease-assisted extraction of oils and proteins from fruit seeds/kernels was tested.•The protease reaction improved the oil extractability for most of the tested substrates.•The protease assisted extraction allowed to obtain good yields of protein hydrolysates.•Some protein hydrolysates of fruit seeds/kernels show promise for hypoallergenic products.•Protease-derived oils possessed higher nutritional value than fruit protein hydrolysates. This research evaluated the application of a one-pot enzymatic extraction by using a protease for the concomitant and sustainable extraction of oils and proteins from fruit seeds/kernels of different species of stone, citrus and exotic fruits. The proteolysis improved the oil solvent-extractability of seeds/kernels of some fruit species compared to the use of acid and/or organic solvents and led to directly recover fat (10–33%) from mango, lemon and pumpkin seeds. Good protein extraction yields were obtained compared to conventional solvent extractions and with a good hydrolysis degree (almost 10%) in the case of lemon and pumpkin seed protein hydrolysates. The nutritional quality of all the protein hydrolysates was quite low, because of their limiting amino acids (histidine, methionine and lysine). On the contrary, the fruit seed/kernel oils resulted with high nutritional value, as they were mostly rich in unsaturated fatty acids, primarily oleic acid (>25%) and linoleic acid (till 40%).