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2-Phenylethanol (2-PE) and 2-phenethyl acetate (2-PEA) are valuable generally recognized as safe flavoring agents widely used in industry. Perfumes, pharmaceuticals, polishes, and personal care products, are some of the final products using these compounds as additives due to their rose-like odor. Also, 2-PE is used in disinfectants, pest control, and cleaning products due to its biocide capability. Although most of these additives production are derived from chemical synthesis, the current trend of consumers to prefer natural products has contributed to the development of biotechnological approaches as an alternative way to obtain natural 2-PE and 2-PEA. The most efficient route to bioproduce these compounds is through the bioconversion of L-phenylalanine via the Ehrlich pathway, and most of the advances have been focused on the development of this process. This review compiles the most recent developments in the biotechnological production of 2-PE and 2-PEA, indicating the most studied strains producing 2-PE and 2-PEA, the current advances in the in situ product recovery in liquid systems, an overview of the strain developments, and the progress in the use of residue-based systems. Future research should address the need for more sustainable and economic systems such as those using wastes as raw materials, as well as the scale-up of the proposed technologies.

2-Phenylethanol (2-PE) and 2-phenethyl acetate (2-PEA) are important aroma compounds widely used in food and cosmetic industries due to their rose-like odor. Nowadays, due to the growing demand for natural products, the development of bioprocesses for obtaining value-added compounds has become of great significance. 2-PE and 2-PEA can be produced through the biotransformation of L-phenylalanine using the generally recognized as safe strain Kluyveromyces marxianus. L-phenylalanine bioconversion systems have been typically focused on submerged fermentation processes (SmF), but there is no information about other alternative productive approaches. Here, the solid-state fermentation (SSF) of sugarcane bagasse supplemented with L-phenylalanine was investigated as a sustainable alternative for producing 2-PE and 2-PEA in a residue-based system using Kluyveromyces marxianus as inoculum. An initial screening of the operational variables indicated that air supply, temperature, and initial moisture content significantly affect the product yield. Besides, it was found that the feeding strategy also affects the production and the efficiency of the process. While a basic batch system produced 16 mg products per gram of residue (dry basis), by using split feeding strategies (fed-batch) of only sugarcane bagasse, a maximum of 18.4 mg Products  g -1 residue were achieved. Increase in product yield was also accompanied by an increase in the consumption efficiency of nutrients and precursor. The suggested system results as effective as other more complex SmF systems to obtain 2-PE and 2-PEA, showing the feasibility of SSF as an alternative for producing these compounds through the valorization of an agro-industrial residue.