TECHNOLOGY FOCUS - FOOD - Preferred Method: The composting and treating food waste involves:(A) mixing food waste with wood chips and separating solid organic materials from food waste by absorbing to wood chips;(B) collecting wood chips to which organic materials are absorbed and fermenting under aerobic conditions to obtain organic compost;(C) treating effluents generated from food waste after organic materials are separated under pressure, to move untreated suspended particles to upper part and move supernatant in which organic materials are dissolved to lower part;(D) transferring suspended particles and fermenting to obtain organic compost, while denitrifying nitrate nitrogen (NOx-N) included in sludge, which is fed through return line by using organic materials remaining resulting supernatant as carbon source;(E) degrading organic materials remaining in resulting material under aerobic conditions using aerobic microorganism and oxygen;(F) denitrifying nitrate nitrogen included in resulting material using short-chain organic acids as a carbon source;(G) separating resulting material into precipitated sludge and a supernatant; and(H) transferring precipitated sludge through return line and chemically treating supernatant to remove non-biodegradable materials.The wood chips are mixed with food waste in wt. ratio of 45:55-55:45. The fermentation process is carried out at 50-70 degrees C for 3-5 days. The denitrification process in step (D) is carried out 25-35 degrees C for 3-6 hours. The aerobic degradation process is carried out at 25-35 degrees C for 10-15 hours. The denitrification process in step (F) is carried out at 25-35 degrees C for 3-6 hours. The chemical treatment process is carried out in presence of a coagulant including aluminum-based or iron-based coagulant.x=not defined.Preferred Components: The wood chips having average size of 2-5 cm is a mixture of equal amounts of fresh wood chips and recycled wood chips which have passed though fermenting process. The amount of food waste fed into first wood chip absorbing tank is 68-70 kg/L per day. The hydraulic retention time of food waste in each of the first and second wood chip absorbing tanks is 20-24 hours. The dissolved oxygen of first, second, and third compartment are maintained at 0.5-1.0 mg/L, 0.2-0.5 mg/L, and 0.1 mg/l or below, respectively.