Provided are systems and methods for real-time sampling and analysis of biomolecules beneath the surface of biological/agricultural tissue/sample. A method for determining fatty acid profiles in agricultural products (for example seeds) comprises using matrix-assisted laser desorption ionization (MALDI) mass spectroscopy or laser ablation electrospray ionization (LAESI) mass spectroscopy. The MALDI or LAESI mass spectroscopy may be used to profile certain fatty acid traits, such as docosahexanoic acid (DHA), in oil seeds. The disclosed method may be used for a high throughput and/or automated screening of agricultural products, such as seeds, for desirable traits or events.
