การพัฒนาวิธีการวิเคราะห์สารประกอบเฟอร์โรไซยาไนด์ในเครื่องดื่ม

Development of determination method for ferrocyanide compound in beverages.

Abstract

The main objective of this project was development of a new determination method for ferrocyanide compound in beverage samples. The efficient comparison study of two methods was evaluated and the appropriated method was chosen to determine ferrocyanide compound. The studied methods were titration and spectrophotometric method. Initially, decomposition of ferrocyanide compound was performed by reacting with 4.00× 10-4 M HgCl2 to generate Fe2+. The generated Fe2+ was formed red color complex compound with 2.00× 10-3 M 1,10-Phenantroline. The amount of this compound was detected by using titration with Ce4+ standard solution or spectrophotometric detection at 510.5 nm. The results indicated that, the calibration curve of spectrophotometric method provided linear equation of Y = 9691.7X + 0.0337 and linear regression of 0.9997. Method Detection Limit (MDL) 0.14 mg-K4Fe(CN)6dm-3, percentage of recovery (%R) 117.44 ± 0.79, qualitative detection limit 0.18 mg-K4Fe(CN)6dm-3 and analysis cost of 24 baht/sample, respectively were evaluated by this method. In the case of titration technique, it was found MDL of 39.70 mg-K4Fe(CN)6dm-3, %R of 109.32 ± 2.25 and analysis cost of 1.5 baht/sample, respectively. Both techniques were environmental friendly and time consumption of 2 hours/sample. However, the titration method was easier and used more basic apparatuses in general laboratory than spectrophotometric method. Then this technique was a good choice of method for determination of ferrocyanide compound and academic service to community. In this work, titration method was selected for ferrocyanide determination in 9 types of 43 beverage samples. Moreover, all of samples were not detected ferrocyanide compound (<39.70 mgdm-3). The results of 9.21 milligram added of ferrocyanide in samples were found the average %R in energy drinks of 119.80, fruit juice of 106.02, soft drinks of 106.30, coffee of 120.37, Surachae of 96.98, beer of 106.41, Thai whisky of 87.38, export whisky of 86.78 and tradition wine of 104.71, respectively.
In conclusion, the results were satisfactory for ferrocyanide determination.