EFEKTIVITAS PERLAKUAN OZON TERHADAP MUTU KANGKUNG KHAS LOMBOK YANG DIBUDIDAYAKAN PADA DUA LOKASI BERBEDA

The aimed of this research was to investigate the methode of ozone application for maintaining the quality of Lombok swamp cabbage cultivated on two different area. The main focus of this research was to identify the heavy metal and pathogen contamination on swamp cabbage those were cultivated in different area of Jangkok riverside. The experiments were conducted in laboratory of food microbiology of faculty of food science and technology and laboratory analitical chemistry of science faculty, university of Mataram. The experiments were arranged with completely randomized disign. The treatment design was factorial with three replications. The first factor was the length of rinsing with ozonized water: 3, 5, and 7 minutes, and the other was swamp cabbage cultivation area: upper stream and down stream area of riversides. Parameter for observation were moisture, ash, Pb content, weight loss, color, texture, appearence and total bacteria especially Escherichia coli  of swamp cabbage samples. The result showed that the longer time of rinsing with ozonized water, the lower Pb content of swamp cabbage. The Pb content of swamp cabbage of upper stream area reduced significantly, however  the Pb content was higher than that of lower stream. The total bacteria of swamp cabbage of lower stream was higher than that of upper stream. Rinsing swamp cabbage for 7 minutes enable total bacteria contaminant reduce significantly, and effective for swamp cabbage with lower Pb content.   Keywords : heavy metal, ozone, pathogen bacteria, swamp cabbage   ABSTRAK Penelitian ini bertujuan untuk menentukan metode aplikasi ozon yang paling tepat untuk mempertahankan mutu kangkung segar yang dibudidayakan di pulau Lombok dan secara khusus untuk mengetahui jenis kontaminan dan waktu kontak larutan ozon terhadap penurunan residu cemaran logam Pb dan bakteri Escherichia coli  pada kangkung Lombok yang dibudidayakan pada lokasi berbeda. Penelitian ini dilakukan di laboratorium Mikrobiologi Pangan Fatepa dan laboratorium Kimia Analitik FMIPA Universitas Mataram. Percobaan ditata menggunakan Rancangan Acak Lengkap (RAL) dengan 2 faktor, yaitu lama perendaman dengan air ozon selama 0, 3, 5, dan 7 menit dan lokasi budidaya kangkung sepanjang daerah aliran sungai (DAS) Jangkuk, yaitu DAS hulu dan DAS hilir. Setiap kombinasi perlakuan dibuat tiga ulangan. Variabel pengamatan meliputi kadar Pb, kandungan E.coli, susut bobot, kadar air, warna daun dan batang kangkung segar. Hasil penelitian menunjukkan bahwa Lama perendaman dengan air berozon dan lokasi budidaya berpengaruh terhadap kadar Pb dan total mikroba E.coli kangkung segar khas Lombok. Kadar Pb makin menurun dengan makin lamanya waktu perendaman menggunakan air berozon. Kadar Pb. terendah ditunjukkan pada kangkung segar yang direndam dalam air berozon selama 7 menit. Kadar Pb kangkung segar yang dibudidayakan pada DAS hulu lebih tinggi daripada DAS hilir. Sebaliknya dengan jumlah mikroba patogen E. coli, kangkung segar dari DAS hilir mengandung mikroba lebih tinggi daripada DAS hulu. Perendaman air berozon efektif menekan jumlah mikroba patogen E coli pada kangkung dengan kandungan logam berat rendah   Kata kunci: bakteri patogen, kangkung, logam berat, ozo