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PENETAPAN KADAR KALSIUM DAN BESI DALAM UMBI UBI KAYU (Manihot esculenta Crants)
SECARA SPEKTROFOTOMETRI SERAPAN ATOM
ABSTRAK
Umbi ubi kayu merupakan tanaman yang murah dan cukup populer di Indonesia. Umbi ubi kayu yang telah dipanen biasanya diawetkan dengan cara dibuat menjadi gaplek karena selama penyimpanan ubi kayu cepat rusak. Umbi ubi kayu ada dua jenis yaitu umbi ubi kayu kuning dan umbi ubi kayu putih. Umbi ubi kayu dan berbagai olahannya mengandung zat gizi yang cukup tinggi. Zat gizi yang terdapat dalam umbi ubi kayu yaitu karbohidrat, lemak, protein, vitamin (A dan B1), mineral (kalsium, besi dan fosfor). Penelitian ini bertujuan untuk mengetahui kadar kalsium dan besi pada umbi ubi kayu kuning, umbi ubi kayu putih dan umbi ubi kayu yang telah diawetkan (dikeringkan) yaitu gaplek umbi ubi kayu kuning dan gaplek umbi ubi kayu putih serta mengetahui persentase peningkatan kadar kalsium dan besi pada gaplek umbi ubi kayu kuning dan gaplek umbi ubi kayu putih.
Sebelum dilakukan analisis terlebih dahulu sampel didestruksi kering, kemudian analisis kuantitatif kalsium dan besi dilakukan dengan menggunakan metode spektrofotometri serapan atom (AAS) yaitu kalsium pada panjang gelombang 422,7 nm dan besi pada panjang gelombang 248,3 nm dengan nyala udara-asetilen. Keuntungan dari metode ini yaitu mempunyai kepekaan yang tinggi (batas deteksi kurang dari 1 ppm) dan pelaksanaannya relatif sederhana.
Hasil penelitian menunjukkan kadar kalisum dalam umbi ubi kayu kuning sebesar (29,6768 ± 0,5899) mg/100 g, umbi ubi kayu putih sebesar (33,6412 ± 0,4633), gaplek umbi ubi kayu kuning sebesar (60,5842 ± 0,5701) mg/100 g dan gaplek umbi ubi kayu putih sebesar (61,7633 ± 0,8617). Kadar besi dalam umbi ubi kayu kuning sebesar (0,4212 ± 0,0065) mg/100 g, umbi ubi kayu putih sebesar (0,4396 ± 0,00171) mg/100 g, gaplek umbi ubi kayu kuning sebesar (0,8690 ± 0,0055) mg/100 g dan gaplek umbi ubi kayu putih sebesar (0,8081 ± 0,0981) mg/100 g.
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DETERMINATION OF CALCIUM AND IRON LEVELS IN CASSAVA TUBER (Manihot esculenta Crants) BY SPECTROPHOTOMETRY ATOMIC ABSORPSTION
ABSTRACT
Cassava tuber is a plant that is inexpensive and quite popular in Indonesia. The cassava tuber that have been harvested usually preserved became cassava chips because during storage they are perishable. There are two types of cassava tuber namely yellow cassava tuber and white cassava tuber. Cassava tuber and various processed products containing high nutrient. Nutrients contained in the cassava tuber namely carbohydrates, fats, proteins, vitamins (A and B1), minerals (calcium, iron and phosphorus). This research aims to determine levels calcium and iron in yellow cassava tuber, white cassava tuber and cassava tuber have been preserved or dried namely yellow cassava chips and white cassava chips also to determine persentage increase in the mineral contens of yellow cassava chips and white cassava chips.
Before analysis sample have destructed using dry destruction method, then the quantitative analysis of calcium and iron were done using atomic absorption spectrophotometry (AAS) at the wavelength of 422.7 nm for calcium and 248.3 nm for iron with air-acetylene flame. Advantages of this method are to have a high sensitivity (limit of detection of lesst han1ppm) and the implementation is relatively simple.
The results show that calcium levels in yellow cassava tuber (29.6768 ±0.5899) mg/100g, white cassava tuber (33.6412 ±0.4633), yellow cassava chips (60.5842 ± 0.5701) mg/100g and white cassava chips (61.7633± 0.8617) mg/100 g. Ironlevelsinyellow cassava tuber (0.4212 ±0.0065) mg/100g, white cassava tuber (0.4396 ±0.00171) mg/100 g, yellow cassava chips (0.8690 ± 0.0055) mg/100g and white cassava chips (0.8081 ±0.0981) mg/100 g.
