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PENETAPAN KADAR MINERAL KALSIUM, MAGNESIUM,
BESI DAN MANGAN PADA KECIPIR (
Psophocarpus
tetragonolobus
(L.) SECARA SPEKTROFOTOMETRI
SERAPAN ATOM
Abstrak
Indonesia dikenal dengan keragaman sumber daya genetik tanaman yang sangat tinggi. Salah satu diantaranya ialah kecipir (Psophocarpus tetragonolobus
(L.)DC.). Semua bagian tanaman kecipir, kecuali batang, dapat dikonsumsi yaitu daun, bunga, polong muda, biji baik biji segar maupun kering dan umbi. Pemanfaatan polong muda sebagai sayuran banyak dijumpai di Asia Tenggara. Kecipir merupakan sumber protein yang baik, selain itu kecipir juga mengandung mineral-mineral penting seperti kalsium, zink, sodium, potasium, magnesium, fosfor, mangan, dan besi. Mineral memegang peran penting dalam pemeliharaan fungsi tubuh. Penelitian ini bertujuan untuk mengetahui kadar mineral kalsium, magnesium, besi dan mangan yang terdapat dalam polong muda kecipir segar dan polong muda kecipir rebus serta persentase penurunan kadar mineralnya.
Sampel dibersihkan dan dicuci dengan akuademineralisata lalu ditiriskan dan dipotong ± 2 cm, untuk sampel segar potongan sampel langsung diblender dan untuk sampel rebus di rebus pada air mendidih selama 15 menit lalu ditiriskan dan didinginkan. Kemudian kedua sampel didestruksi kering dan dibuat larutan sampel, selanjutnya dilakukan uji kuantitatif secara spektrofotometri serapan atom (AAS) menggunakan gas pembakar udara-asetilen untuk logam kalsium pada 422,7 nm, untuk logam magnesium pada 285,2 nm, untuk logam besi pada 248,3 nm dan untuk logam mangan pada 279,5 nm. Keuntungan dari metode ini adalah sensitif dan selektif.
Hasil penetapan kadar kalsium, magnesium, besi dan mangan dalam polong muda kecipir segar dan polong muda kecipir rebus diperoleh kadar kalsium (30,7430 ± 0,2898) mg/100 g dan (26,5849 ± 0,2225) mg/100 g. Kadar magnesium (33,8027 ± 0,2358) mg/100 g dan sebesar (24,4033 ± 0,1572) mg/100 g. Kadar besi (0,4571 ± 0,0118) mg/100 g dan (0,4239 ± 0,0078) mg/100 g. Kadar mangan (0,0002962 ± 0,0000053) mg/100 g dan (0,0002268 ± 0,0000054) mg/100 g. Persentase penurunan kadar pada polong muda kecipir setelah direbus yaitu untuk kalsium 13,52%, untuk magnesium 27,80%, untuk besi 7,26% dan untuk mangan 23,39%. Secara statistik uji beda rata–rata kandungan kadar kalsium, magnesium besi dan mangan dengan menggunakan distribusi F, diperoleh bahwa kandungan kalsium, magnesium, besi dan mangan pada polong muda kecipir segar lebih tinggi secara signifikan dari polong muda kecipir rebus.
Kata Kunci: Polong Muda Kecipir Segar, Polong Muda Kecipir Rebus, Destruksi, Kalsium, Magnesium, Besi dan Mangan, Spektrofotometer Serapa n Atom
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DETERMINATION OF MINERAL LEVELS OF CALCIUM, MAGNESIUM IRON AND MANGANESE IN WINGED BEAN
(Psophocarpus tetragonolobus (L.) IN ATOMIC ABSORPTION
SPECTROPHOTOMETRY
Abstract
Indonesia is known for the diversity of plant genetic resources is very high. One of them is the winged bean (Psophocarpus tetragonolobus (L.) DC.). All parts of the plant winged bean, except the stem, can be consumed ie leaves, flowers, young pods, seeds either fresh or dried beans and tubers. Utilization of young pods as vegetables are often found in Southeast Asia. Winged is a good source of protein, in addition winged bean also contains important minerals such as calcium, zinc, sodium, potassium, magnesium, phosphorus, manganese, and iron. Minerals are part of the body and plays an important role in the maintenance of body functions. This study aims to determine the mineral content of calcium, magnesium, iron and manganese contained in winged young pods of fresh and young pods boiled cowpeas as well as the percentage decrease in the levels of minerals.
Samples that have been purchased cleaned and washed with akuademineralisata then drained and cut ± 2 cm, for fresh sample piece sample to sample directly blended and boiled boiled in boiling water for 15 minutes then drained and cooled. Then the two samples dried destruction and made sample solution, further quantitative assay atomic absorption spectrophotometry (AAS) using air-acetylene gas burner for calcium metal at 422.7 nm, for magnesium
metal at 285.2 nm, for ferrous metals at 248.3 nm and for manganese metal at
27λ.5 nm. Advantages of this method is sensitive and selective.
Results of the assay of calcium, magnesium, iron and manganese in the winged young pods of fresh and young pods are boiled cowpeas atomic absorption spectrophotometry, following third consecutive, calcium levels (30.7430 ± 0.2898) mg / 100 g and (26.5849 ± 0.2225) mg / 100 g. Levels of magnesium (33.8027 ± 0.2358) mg / 100 g and the amount of (24.4033 ± 0.1572) mg / 100 g. Iron content (0.4571 ± 0.0118) mg / 100 g and (0.4239 ± 0.0078) mg / 100 g. The manganese content (0.0002962 ± 0.0000053) mg / 100 g and (0.0002268 ± 0.0000054) mg / 100 g. The percentage decrease in the levels of young winged bean pods after boiling ie 13.52% for calcium, for magnesium 27.80%, to 7.26% iron and 23.39% for manganese. Statistically different test average of the content of calcium, magnesium, iron and manganese using the F distribution, found that calcium, magnesium, iron and manganese in the young pods of fresh cowpeas significantly higher than young pods winged bean stew.
Keywords: Winged Young Fresh pods, pods Young Winged Simmer,
destruction, Calcium, Magnesium, Iron and Manganese, Atomic Absorption Spectrophotometer
