Analysis of vitamin K in green tea leafs and infusions by SPME–GC-FID

Analysis of vitamin K in green tea leafs and infusions by SPME–GC-FID

Author: Márcia Reto and Maria E. Figueira and Helder M. Filipe and Cristina M.M. Almeida

The usual methods for determination vitamin K are laborious. With the aim of replace them by a simpler method that requires fewer solvents, lower analytical levels and allows reporting of results in a smaller period of time, a procedure based on solid-phase microextraction (SPME) and gas chromatography with flame ionization detector (GC-FID) was developed. This method was used to analyse vitamin K in green tea leafs and infusions from nine brands of green tea commercialised in Portugal. The best analytical conditions were obtained using PDMS 7 μm fibre using immersion extraction at 40 °C, for 45 min and 1300 rpm. The linear range for vitamins K1 and K2 was defined. The detection limits obtained with PDMS fibre and GC/FID were 0.16 and 0.07 mg/L for vitamins K1 and K2, respectively. In all analysed infusions the concentration of vitamin K was lower than the detection limit of the developed method, however, the concentration of vitamin K1 present in tea leafs was between 120 and 625 μg/100 g.

 

Get the whole article here

Shipping Icon Free shipping on subscriptions + orders over $49 (US only)

{property.value} {property.value} {property.value} Include jar: {property.value}

Delivery every {property.value}

{property.value}

+
You definitely need tools!
Perfect coldbrew everytime
The ideal way to store your matcha
The ideal way to store your matcha