TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The renewable bio feedstock component acts as a bio diesel which is the product of trans-esterification of naturally occurring whole oils of plants or animals with an alcohol, or the ester of a fatty acid derived from naturally occurring oils, and an alcohol. The petroleum based component is described as a middle distillate fuel, a heavy fuel oil, a jet fuel or a Fischer-Tropsch fuel. The petroleum based component contains sulfur less than or equal to 5000 (preferably 500, especially 17) ppm. The fuel contains renewable bio feedstock component (0-100, preferably 1-30) vol.%; petroleum based component (0.1-100, preferably 70-99) vol.%. The multifunctional stabilizer package is described as a suitable combination of at least one members of free radical chain termination agent, peroxide decomposition agents, acid scavenger, photochemical stabilizer, gum dispersant or metal sequestering agent. The formulation contains (wt.%) free radical chain termination agent (0-100, preferably 25-85), free radical decomposition agent (0-100, preferably 15-65), photochemical stabilizer (0.0-100, preferably 0.0-10), and metal sequestering agent (0-25, preferably 1-3). The fuel oil composition additionally comprising or obtainable by mixing the additive with carriers or diluents. The fuel composition is in combination with additives selected from static dissipaters/electrical-conductivity improver additive, low temperature operability/cold flow additives, corrosion inhibitors, lubricity improvers, cetane improvers, detergents, or dyes and markers. The petroleum component of the bio/petroleum blends is a middle distillate fuel containing sulfur. Preferred Components: The natural oils are selected from soy, palm, rapeseed, linseed, coconut, corn, cotton, cooking, sunflower, safflower, tallow, lard, yellow grease, fish oils and/or their blends. The alcohol is selected from linear, branched, alkyl, aromatic, primary, secondary, tertiary or polyols. The free radical chain termination agent is selected from alkyl phenols, alkyl phenylenediamines, quinones or nitro compounds. The alkyl phenols are selected from alkyl phenols (2,6-di-tertbutyl phenol, 2,6-di-t-butyl-4- methylphenol (BHT), 2,4-dimethyl-6-t-butylphenol, tert-butyl-4-hydroxyanisole (BHA)); dihydroxy benzenes (1,4-dihydroxy benzene 1,3-dihydroxy benzene, 1,2-dihydroxybenzene); trihydroxy benzenes (1,2,3 trihydroxy benzene); poly cyclic aromatics containing one to three hydroxyl groups and gallic acid derivatives (octyl gallate). The alkyl phenylenediamines are selected from (N,N'-di-sec-butyl-p-phenylenediamine or N-sec-butyl-p-phenylenediamine. The quinones compounds are selected from 2,3,5-trimethylbenzoquinone, 2,3-dimethylbenzoquinone, 2,3-dimethoxy-5-methylbenzoquinone, 2-methylnaphthoquinone, t-butylhydroquinone (TBHQ). The nitro compounds are selected from nitro benzene, di-nitrobenzene, nitro-toluene, nitro-napthalene or di-nitro napthalene. The photochemical stabilizer is selected from hindered amine light stabilizers. The gum dispersant is a polymeric dispersants selected from the polymers of: ethylene and unsaturated esters; vinyl alcohols, vinyl ethers and their ester with organic acids; propylene, ethylene, isobutylene adducts with unsaturated carboxylic acids (such as maleic and fumaric acids) and their amide or imide derivatives; acrylic acids and their amide or esters derivatives and/or poly styrenes. The metal sequestering agents are selected from DMD, citric acid or ethylene diamine tetraacetic acid (EDTA) (preferably DMD). The carriers and diluents are selected from aromatic, aliphatic hydrocarbons; alcohols or carbonyl containing material such as aldehydes, ketones, esters or amides. The peroxide decomposition agents are selected from sulfur, nitrogen or phosphorus compounds (preferably nitrogen compound of formula N(R)(R1)(R2)). The acid scavengers are selected from primary, secondary, tertiary amines or their derivatives (preferably compound of formula N(R3)(R4)(Z1)).R2=alkyl-linear, branched, saturated, unsaturated 1-30C aromatic, cyclic, poly alkoxy, poly-cyclic;R, R1=alkyl-linear, branched, saturated, unsaturated 1-30C aromatic, cyclic, poly alkoxy, poly-cyclic (optionally substituted by other hetero atoms such as O, N, S or P, and their resultant functional groups, a cyclic system containing 3 to 12 atoms);R3, R4=1-30C H, alkyl-linear, branched, saturated, unsaturated, aromatic, cyclic, poly alkoxy or carbonyl (optionally substituted by hetero atoms such as O, N, S and P or their resultant functional groups, cyclic system containing 3-12 members;Z1=R3 or -(-CH2-(CH2)x-N(R3)2;X and Y1=1-6. EXAMPLE - A fuel composition (test) comprising (wt.%) Soy B100, 2,6-di-tert-butylphenol (75), N,N-dimethyl cyclohexyl amine (25) was prepared. n- The sample was then evaluated using the UV analysis method for fuel stability against comparative fuel composition without adding any additive. The test composition showed higher stablity than comparative composition.