NOVELTY - Biorefinery in which starting material is converted into fermented solids and evaporable agents by lactic acid fermentation, where the starting material is biomass.    USE - The method is useful for producing fermented solids and evaporable agents. The fermented solids are used as food product. The food product is useful as animal feed, preferably pig feed (all claimed). The fermented solids are useful as soil conditioner for improving physical properties of soil, such as water retention, permeability, water infiltration, drainage, aeration and structure and providing nutrition for plants. The evaporable agents are water and organic compounds chosen from ethanol, acetic acid, propionic acid, butanol and propanol which are used as e.g. energy or industrial chemicals, specifically ethanol is useful for replacing fossil fuels in the transport sector.    ADVANTAGE - The method is cost-effective, utilizes low-value biomass, produces value-added biomass, capable of operating continuously with minimal long term effect and consumes industrial waste energy and low-temperature waste heat. The animal feed contains organic acid e.g. lactic acid and acetic acid which maintains ideal pH and inhibits microorganism that causes food to spoil and hence it enhances good health of pig and piglet and provides improved microbiological stability and safety of the foodstuffs. The feed contains live lactic acid probiotic bacteria which can inhibit pathogens and toxin producing bacteria.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for converting biomass into fermented solids and evaporable agents by lactic acid fermentation, which involves (a) heating the biomass at 55-75 degrees C, (b) inoculating the biomass with lactic acid bacteria, (c) fermenting the biomass at 27-37 degrees C in a pH of 3.5-5, (d) performing vacuum distillation of fermented product at 45-55 degrees C under vacuum pressure of about 1 bar, and (e) recovering fermented solids and distilled evaporable agents.