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

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%).

Influence of the killing method of the black soldier fly on its lipid composition.

Black soldier fly (BSF, Hermetia illucens) represents a valuable source of biomolecules and it also constitutes an economic way to valorise residual biomasses. BSF prepupae contain high amounts of lipids (37% DM basis). The present investigation aimed at studying the composition of BSF lipids and the effect of killing/storage on their quality. The main fatty acid was lauric acid, sterols were represented primarily by beta-sitosterol and campesterol. Global fatty acid and sterol profiles, determined by GC-MS, were only slightly affected by the killing procedure, while lipid classes distribution, determined by 1H NMR, strongly changed. Prepupae killed by freezing showed a drastic reduction of acylglycerols during storage and a relevant release of free fatty acids, likely due to activation of lipases. On the contrary, prepupae killed by blanching have a stable lipid fraction constituted mainly by triacylglycerols. Therefore, killing procedure strongly influences BSF oil composition and the potential applications.

Characterization of a potential nutraceutical ingredient: pomegranate (Punica granatum L.) seed oil unsaponifiable fraction.

The chemical fingerprinting of the unsaponifiable fraction of different Punica granatum seed oils was performed in order to evaluate their potential as a functional food ingredient. Qualitative and quantitative determinations of tocopherol, aliphatic alcohol (including policosanol), squalene, phytosterols and triterpene contents were performed by GC-MS. A high yield (3.1-4.2%) of unsaponifiable matter was obtained and consistent levels of squalene (up to 800 mg/kg) and policosanol (118-185 mg/kg) were noticed. ß-sitosterol (up to 8069 mg/kg) and cycloartenol (5916-7766 mg/kg) were predominant in phytosterol and triterpene fractions, while ß- and δ-tocopherol were the most abundant vitamin E forms. Some minor variations were noticed between samples. From the results obtained, it can be suggested that the seed oil of P. granatum can be considered an interesting alimentary source of substances of nutraceutical value involved in the modulation of cholesterol metabolism.