Abstract:

A new oxidation system, in Na2HPO4-KH2PO4 buffer (pH 6.84), with rhodamine B as the spectral probe was proposed for determination of benzoyl peroxide (BPO) in flour. Results indicated that this rhodamine B-BPO had an absorption maximum at 550 nm and the apparent molar absorption coefficient was 1.1×104 L/mol·cm. Beer＇s law was obeyed within the concentration of 0.00 to 0.80 mg/ml. The BPO detection limit by this method was 0.056 mg/ kg. The spike recoveries were between 97.5% and 101.0%, and the RSD were between 1.46% and 2.53%. Due to its easy operation and high recovery, this method could be applied directly to analyze trace benzoyl peroxide in flour.

Key words: rhodamine B, benzoyl peroxide, spectral probe, flour