Sains Malaysiana 39(4)(2010): 581–586

Kesan Infusi Terhadap Kepekatan Fluorida dalam Pelbagai Jenis Teh Cina

(Effect of Infusion on Fluoride Concentration in Various Chinese Tea)

Wong Win Ni & A.R. Suriah*

Program Sains Makanan

Pusat Pengajian Sains Kimia & Teknologi Makanan

Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

Received: 13 August 2009 / Accepted: 1 December 2009

ABSTRAK

Kepekatan fluorida dalam infusi teh komersial bagi sampel teh hitam, teh oolong, teh hijau, teh putih dan teh bata ditentukan dengan menggunakan kaedah elektrod selektif ion fluorida. Dua jenis infusi dilakukan, iaitu infusi berterusan dan infusi berulangan. Dalam infusi berterusan, teh hitam menghasilkan kepekatan fluorida yang paling tinggi, iaitu antara 0.929±0.053 mg/L hingga 3.746±0.028 mg/L. Teh bata pula menghasilkan kepekatan fluorida antara 1.099±0.046 mg/L hingga 2.398±0.006 mg/L. Kepekatan fluorida terlarut bagi teh oolong, teh hijau dan teh putih masing-masing adalah antara 0.584±0.080 mg/L hingga 1.255±0.044 mg/L, 0.624±0.088 mg/L hingga 1.838±0.062 mg/L dan 0.571±0.027 mg/L hingga 1.845±0.017 mg/L. Kandungan kumulatif fluorida dalam infusi berulangan didapati lebih tinggi daripada yang disediakan melalui infusi berterusan bagi semua jenis teh. Hasil kajian menunjukkan kandungan fluorida berbeza-beza dengan jenis teh dan kaedah infusi yang berlainan. Oleh sebab pengambilan fluorida yang berlebihan boleh menyebabkan fluorosis gigi dan fluorosis tulang, maka kerajaan tempatan atau organisasi antarabangsa harus menetapkan suatu piawai keselamatan untuk kandungan fluorida dalam pelbagai jenis teh demi menjamin keselamatan pengguna.

Kata kunci: Fluorida; infusi berterusan; infusi berulang; teh cina

ABSTRACT

The fluoride content in infusions of commercially available black tea, oolong tea, green tea, white tea and bata tea was determined via fluoride ion selective electrode method. Two methods of infusion were carried out: continuous infusion and repeated infusion. In continuous infusion, black tea yielded the highest concentration of fluoride, which ranged between 0.929±0.053 mg/L and 3.746±0.028 mg/L. Fluoride detected in brick tea ranged from 1.099±0.046 mg/L to 2.398±0.006 mg/L. The dissolvable fluoride for oolong tea, green tea, and white tea were ranged from 0.584±0.080 mg/L to 1.255±0.044 mg/L, 0.624±0.088 mg/L to 1.838±0.062 mg/L and 0.571±0.027 mg/L to 1.845±0.017 mg/L, respectively. The cumulative fluoride contents in repeated infusion were higher than those prepared by continuous infusion for all types of tea. Results of the study indicate that there was a wide range of fluoride content with different types of tea and methods of infusion. Because excessive intake of fluoride can cause dental and skeletal fluorosis, it is necessary for the government or international organization to establish a standard of fluoride content in tea commodities in order to protect the consumers against health hazards.

Keywords: Chinese tea; continuous infusion; fluoride; repeated infusion

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*Corresponding author; email: sar@ukm.my