To comply with the clause you referenced
ISO 9001 Sec. 7.1 (d) Records needed to provide evidence that the realization processes and resulting product meet requirements" , you will need to decide the processes and product requirements your company must achieve to meet your objectives of quality, purity, performance, etc. Once these processes and product requirements are define, you should define those criteria or characteristics that relate directly to the quality or performance requirements. Thereafter you should prepare quality assurance methods (test procedures or one-time protocols) that will directly measure the process outputs and product specifications that provide the evidence that the procedures you employ on a routine basis will consistently yeild the process or product required output.
Justify in a fact-based unbiased manner why you test plans (as designed) will generate the data needed to prove the processes achieve the requirements. Use scientific and engineering rationales to support your plans and protocols.
Essentially know what you want to achieve and then test the processes to demonstrate unequivocably that you achieve the objectives.
Finally note that the ISO 9001 standard is now revised: ISO 9001:2008. Don’t implement a quality plan based upon the obsolete standard.
" To claim conformity with ISO 9001:2008, the organization has to be able to provide objective evidence of the effectiveness of its processes and its quality management system. Clause 3.8.1 of ISO 9000:2005 defines “objective evidence” as “data supporting the existence or variety of something” and notes that “objective evidence may be obtained through observation, measurement, test, or other means.”
Objective evidence does not necessarily depend on the existence of documented procedures, records or other documents, except where specifically mentioned in ISO 9001:2008. In some cases, (for example, in clause 7.1(d) Planning of product realization, and clause 8.2.4 Monitoring and measurement of product), it is up to the organization to determine what records are necessary in order to provide this objective evidence. "