ANALISIS KANDUNGAN UNSUR ESENSIAL DAN TOKSIK DALAM TEH DAN AIR SEDUHANNYA DENGAN AKTIVASI NEUTRON

Abstract

Kadar unsur logam K, Ca, Mn, Mg, Fe, Na, Zn, Rb, Br, Cr, Cs, La,Sc dan Co dalam 14 sampel teh hijau, teh hitam, teh hitam dengan aroma melati, aroma vanila, bunga rosella dan air seduhan teh telah ditentukan dengan analisis aktivasi neutron. Sampel teh dipilih dari produksi dalam negeri dan diperoleh dari Pasar Swalayan di daerah Serpong. Iradiasi neutron sampel dilakukan di Fasilitas Iradiasi reaktor RSG-GAS pada fluks neutron thermal sekitar sekitar 10¹³ ncm^-2s^-1. Prosedur kerja menggunakan SOP yang dikeluarkan oleh FNCA. Sebagai kontrol mutu digunakan SRM-NIST 1573a Tomato leaves dan NIST 1547 Peach leaves. Hasil analisis menunjukkan bahwa konsentrasi semua unsur bervariasi tergantung jenis teh. Konsentrasi Ca, K, Mg dan Mn dalam teh cukup tinggi > 100 mg/kg . Konsentrasi Ca dan K memiliki rentang nilai antara 1135,36-9123,21 dan 1064,41-2473,12 mg/kg serta Mg 2725,6-5528,5; dan Mn 95,38-815,48 mg/kg. Unsur mikroesensial Na, Fe, Co, La, Cr, Br, Sc, Cs, Rb dan Zn memiliki konsentrasi < 100 mg/kg. Sebagian besar unsur dalam teh dilepaskan dalam air seduhan dengan persentase berbeda dengan rentang nilai antara 27,89-68,94 % tergantung jenis sampel teh. Tidak terdeteksi unsur toksik Hg, Cd dan As, kecuali unsur Cr dengan konsentrasi masih cukup rendah. Dengan demikian minuman teh cukup baik menjadi sumber unsur esensial bagi tubuh dan tidak mengandung logam toksik.

Kata kunci: analisis unsur, esensial, toksik, teh, aktivasi neutron.

Concentration of metal elements K, Ca, Mn, Mg, Fe, Na, Zn, Rb, Br, Cr, Cs, La,Sc and Co from 14 samples of green and black tea with aroma of jasmine, vanilla, rosella flower and tea infusion have been determined by means of neutron activation analysis. The Samples were chosen from the domestic product and were collected from Supermarket in Serpong region. Neutron irradiation of the samples was carried out in the Irradiation Facility of the RSG-GAS reactor at thermal neutron flux in the order of 10¹³ ncm^-2s^-1. The working procedures follow the Standard Operating Procedures of FNCA. As of the quality control the reference material of SRM-NIST 1573a Tomato leaves and NIST 1547 Peach leaves.have been applicated. The analysis results show that concentration of the elements variate depending on the sort of tea. Concentration of Ca, K, Mg dan Mn have a rather high value namely > 100 mg/kg. Concentration of Ca and K have values in a range of 1135.36-9123.21 and 1064.41-2473.12 mg/kg as well as Mg of 2725.6-5528.5; and Mn of 95.38-815.48 mg/kg.Concentration of Na, Fe, Co, La, Cr, Br, Sc, Cs, Rb and Zn <100 mg/kg. Most elements in these tea were released into the infusions at defferent percentages in a range of 27.89-68.94% depending on the sort of the tea. There were not detected toxical elements Hg, Cd and As except Cr with low concentration. Therefore tea drink sare adequately good enough as essential elements source and content no toxic elements.

Keywords: elemental analysis, essential, toxic, tea, neutron activation.