Study On The Method Of Detecting Food Preservative Nipagin Esters

Nipagin esters is one of the three internationally recognized efficient food preservatives. It has been used in the food industry of the USA, Europe, Japan, Canada, South Korea, Russia, and other countries. According to the hygienic standard GB2760 of our country, ethylparaben and isopropylparaben can be used as food preservatives. However, recent surveys have shown that N and estrogens work in a similar way in the human body, which may have some underlying adverse effects. Its safety needs reevaluating.Adopting international and domestic advanced detecting techniques and the equipment available at domestic food testing institutions, this research investigates the detecting methods of N in the soy, beverages, and the dried tofu and explores a stable, simple, and quick method to detect the food preservative nipagin esters.This experiment adopts the effective liquid chromatograph equipped with diode-array detector, and detects methylparaben,ethylparaben,n-propylparaben and isopropylparaben simultaneously. The immediate detection after the dilution of specimens of beverages and the soy prevents the damage of organic solution and omits the liquid-liquid extraction process.No one has detected nipagin esters in dried tofu at home and abroad. In this essay, we cut dried tofu specimen into pieces, extract N with absolute ethyl alcohol which is of low toxicity, and get a desirable detection result.This essay optimizes the method of detecting nipagin esters in food, which adopts the effective liquid chromatograph equipped with diode-array detector. The best detection wavelength is 254 nm, the mobile phase is carbinol and ammonium acetate of 0.02 mol/L, and the chromatographic column is Agilent Eclipse XDB-C18.The recovery rate of these three specimens ranges from 90% to 105%, RSD value from 0.5% to 2%, the liner relation is good when the density ranges from 0.5μg/mL to 200μg/mL, the correlation coefficient of methylparaben,ethylparaben,isopropylparaben reaches 1, and n-propylparaben is 0.9999,the detection limits of these four esters are 0.032μg/mL,0.046μg/mL,0.035μg/mL,0.046μg/mL.The innovation of this essay is that it has confirmed a method of detecting nipagin esters in the direct diluted beverage and soy and has established a simple, quick,and accurate method to detect nipagin esters in dried tofu.