Fast and sensitive method for phosphorus determination in dairy products

Abstract

The spectrophotometric molybdenum blue method for phosphorus determination was adapted to a multiwell plate format. The method was sensitive and allowed for the simultaneous determination of phosphorus in many samples. It was cheap and eco-friendly due to application of small volumes of reagents and, therefore, it meets the requirements for “green” or sustainable chemistry. The method’s limit of detection (LOD) is 0.37\xa0μg/mL and its limit of quantification (LOQ) is 1.13\xa0μg/mL. Its linearity is up to 30\xa0μg of phosphorus/mL. The method was applied for the determination of phosphorus in 65 dairy products (yogurts, yogurt drinks, buttermilks, kefirs and homogenized cheeses) of strawberry, peach, forest fruits, vanilla and other flavours. The phosphorus content was 143–226\xa0mg/100\xa0g in flavoured yogurts, 78–204\xa0mg/100\xa0g in yogurt drinks, 89–218\xa0mg/100\xa0g in kefirs, around 195\xa0mg/100\xa0g in buttermilks, and 165–277\xa0mg/100\xa0g in homogenized cheeses. The presented method can be used in the routine quantitative analysis of the total phosphorus content in dairy products.