the term "security interest" means any interest in property acquired by contract for the purpose of securying payment or performance of an obligation or indemnifying against loss or liability. A security interest exists at any time (A) if at such time, the property is an existance an the interest has become protected under local law against a subsequent judgement lien arising out of an unsecured obligation, and (B) to the extend that, at such time, the holder has parted with money or money's worth.