Mannitol from grape must and wine lees

Hijosa-Valsero M, Garita-Cambronero J, Paniagua-García AI, Díez-Antolínez R (2021) Mannitol bioproduction from surplus grape musts and wine lees. LWT 151, 112083. https://doi.org/10.1016/j.lwt.2021.112083.

Abstract: Mannitol is a polyol commonly used in food and pharmaceutical industries. Its biological large-scale production is hindered by the elevated costs of fructose-rich feedstocks. Grape must could be an interesting substrate for this process, due to its bulk production and to the commercial imbalance caused by unsold wine stocks. In the present work, red must and white must were assessed as feedstocks for mannitol production employing three Lactobacillales species. It was experimentally determined that nutrient supplementation could be limited to manganese and yeast extract, and that grape must should be diluted with water to improve mannitol production. Under optimal conditions, Lactobacillus intermedius NRRL B-3693 produced 68.9 g/L mannitol from red must and 79.8 g/L mannitol from white must in 48 h, attaining yields of 0.888 and 0.895 mol/mol, respectively. In order to further reduce costs, yeast extract was replaced by wine lees, resulting in mannitol concentrations of 59.4 g/L for red must and 65.6 g/L for white must in 144 h by using red wine lees and L. intermedius NRRL B-3693. Therefore, winery surplus and by-products could be used to produce mannitol, thus opening new biorefinery opportunities.

Link to journal article: https://doi.org/10.1016/j.lwt.2021.112083.

Link to open access repository (preprint version) : https://doi.org/10.5281/zenodo.5091840.

**