Penetapan Kadar Mineral Kalsium, Kalium, Magnesium, dan Natrium Pada Selada Romaine (Lactuca sativa var. longifolia Lam.) Organik dan Non-Organik Secara Spektrofotometri Serapan Atom

PENETAPAN KADAR MINERAL KALSIUM, KALIUM, MAGNESIUM,
DAN NATRIUM PADA SELADA ROMAINE (Lactuca sativa var.
longifolia Lam.) ORGANIK DAN NON-ORGANIK SECARA
SPEKTROFOTOMETRI SERAPAN ATOM
ABSTRAK

Selada romaine merupakan salah satu varietas dari selada yang merupakan
tumbuhan yang berasal dari suku compositae. Tanaman ini banyak dikenal
masyarakat sebagai lalapan. Kandungan gizi dari selada ini antara lain sebagai
sumber mineral, pro-vitamin A, vitamin C, dan serat. Selain ditanam secara nonorganik tanaman ini juga dapat ditanam secara organik. Banyak keuntungan yang
dapat diperoleh dengan mengonsumsi sayuran organik dibanding sayuran nonorganik. Di antaranya rasa lebih manis, tekstur lebih renyah, segar lebih lama, dan
paling penting bebas dari residu bahan kimia yang membahayakan kesehatan.
Tujuan dari penelitian ini adalah untuk mengetahui kadar mineral kalsium,
kalium, magnesium, dan natrium pada selada romaine organik dan non-organik
serta mengetahui perbedaan kadar mineral antara selada romaine organik dan nonorganik.
Untuk mengetahui kadar mineral kalsium, kalium, magnesium, dan
natrium pada selada romaine yang diteliti dilakukan penetapan kadar
menggunakan spektrofotometer serapan atom nyala udara-asetilen. Analisis
kuantitatif kalsium, kalium, magnesium, dan natrium dilakukan pada panjang
gelombang berturut-turut 422,7 nm, 766,5 nm, 285,2 nm, dan 589,0 nm.
Hasil penelitian menunjukkan bahwa kadar mineral kalsium, kalium,

magnesium, dan natrium dalam selada romaine organik adalah (109,2111 ±
0,2454) mg/100g; (575,8676 ± 0,8555) mg/100g; (151,8046 ± 0,1241) mg/100g;
(10,9818 ± 0,2097) mg/100g. Serta kadar mineral kalsium, kalium, magnesium,
dan natrium dalam selada romaine non-organik adalah (66,3873 ± 0,4059)
mg/100g; (366,3379 ± 1,0117) mg/100g; (97,2027 ± 0,1702) mg/100g; (5,2111 ±
0,2533) mg/100g. Hasil uji statistik yaitu uji beda rata-rata kadar mineral antara
selada romaine organik dan non-organik menunjukkan bahwa terdapat perbedaan
yang signifikan kadar masing-masing mineral kalsium, kalium, magnesium, dan
natrium antara selada romaine organik dan non-organik dengan tingkat
kepercayaan 99%.
Kata kunci :

selada romaine (Lactuca sativa var. longifolia Lam.), organik,
non-organik,
kalsium,
kalium,
magnesium,
natrium,
spektrofotometer serapan atom

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Universitas Sumatera Utara

DETERMINATION OF CALCIUM, POTASSIUM, MAGNESIUM
AND SODIUM LEVEL IN ORGANIC AND INORGANIC
ROMAINE LETTUCE (Lactuca sativa var. longifolia Lam.) BY
ATOMIC ABSORPTION SPECTROPHOTOMETRY
ABSTRACT

Romaine lettuce is one of varieties of lettuce which is a local plant of the
compositae. This plant is well known as vegetables are eaten raw. Nutrients
content of this lettuce are as minerals resources, pro-vitamin A, vitamin C, and
fiber. Aside from inorganically grown, these plants can also be grown organically.
Many benefits can be obtained by eating organic vegetables than inorganic
vegetables. It included sweeter taste, crisper texture, fresh for longer, and most
importantly free from chemical residues that harms health. The purpose of this
study are to determine mineral content of calcium, potassium, magnesium, and
sodium in the organic and inorganic romaine lettuce and also knowing the
difference between mineral content of the organic romaine lettuce and the
inorganic romaine lettuce.

To determine the mineral content of calcium, potassium, magnesium, and
sodium in romaine lettuce under study were conducted by using atomic absorption
spectrophotometer with air-acetylene flame. Quantitative analysis of calcium,
potassium, magnesium, and sodium were perfomed at 422.7 nm, 766.5 nm, 285.2
nm, and 589.0 nm wave length.
The results showed that the levels of the minerals calcium, potassium,
magnesium, and sodium in the organic romaine lettuce were (109.2111 ± 0.2454)
mg/100g; (575.8676 ± 0.8555) mg/100g; (151.8046 ± 0.1241) mg/100g; and
(10.9818 ± 0.2097) mg/100g. As well as the levels of the minerals calcium,
potassium, magnesium, and sodium in the inorganic romaine lettuce were
(66.3873 ± 0.4059) mg/100g; (366.3379 ± 1.0117) mg/100g; (97.2027 ± 0.1702)
mg/100g; and (5.2111 ± 0.2533) mg/100g. The results of statistical tests that test
the average difference between the mineral content of the organic romaine lettuce
and the inorganic romaine lettuce showed that there were significant difference of
each mineral contents of calcium, potassium, magnesium, and sodium between the
organic romaine lettuce and inorganic romaine lettuce with a level of confidence
99%.
Keywords :

romaine letuce (Lactuca sativa var. longifolia Lam.), organic,

inorganic, calcium, potassium, magnesium, sodium, atomic
absorption spectrophotometer

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Universitas Sumatera Utara