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Frying Quality of Virgin Coconut Oil as Affected by Zea mays L. Extract (Kualiti
Menggoreng Minyak Kelapa Dara Disebabkan oleh Ekstrak Zea mays L.)
A.M. MARINA*, W.I. WAN ROSLI
& S.L. NEOH
School
of Health Sciences, Health Campus, Universiti Sains Malaysia
16150
Kubang Kerian, Kelantan, Malaysia
Diserahkan:
6 Jun 2013/Diterima: 7 Februari 2014
ABSTRACT
The effect of corn
silk or Zea mays extract on the physicochemical changes of virgin
coconut oil was studied during three consecutive days of deep frying. There
were three types of oil blend systems used: virgin coconut oil without
antioxidant as control system; virgin coconut
oil with butylated hydroxytoluene (BHT) as synthetic antioxidant and virgin
coconut oil with Zea mays extract as natural antioxidant.
The oil quality was assessed by measuring the colour, viscosity, peroxide,
p-anisidine, free fatty acids, totox and iodine value. The results show that Zea
mays extract delayed the oil deterioration. The Zea mays extract
significantly (p<0.05) lowered the rate of oxidation in virgin
coconut oil compared to control oil and was comparable to BHT. Zea mays extract did not change the sensory profiles of French fries
which was shown by insignificant difference (p<0.05) between Zea
mays and control fries for all sensory attributes (colour, taste, aroma,
crispiness, oiliness and overall quality). In general, the Zea may extract
was capable of extending the stability and quality of virgin coconut oil and
therefore has potential as new source of natural antioxidant for use in deep
frying.
Keywords: Fats;
frying; oils; virgin coconut oil; Zea mays
ABSTRAK
Kesan ekstrak sutera
jagung (Zea mays) ke atas perubahan fizikokimia minyak kelapa dara
semasa penggorengan telah dikaji selama tiga hari berturut-turut. Terdapat tiga
jenis campuran minyak yang digunakan: minyak kelapa dara tanpa antioksidan
sebagai kawalan, minyak kelapa dara bersama butylated hydroxytoluene (BHT) sebagai antioksidan
sintetik dan minyak kelapa dara bersama ekstrak Zea mays sebagai
antioksidan semula jadi. Kualiti minyak dinilai dengan mengukur warna,
kelikatan, nilai peroksida, nilai asid lemak bebas, nilai totox dan nilai
iodin. Keputusan kajian menunjukkan bahawa ekstrak Zea mays telah
melewatkan kadar kerosakan minyak. Ekstrak Zea mays telah menurunkan
kadar pengoksidaan minyak secara signifikan (p<0.05) berbanding
dengan minyak kawalan dan setara dengan minyak bercampur BHT.
Ekstrak Zea mays tidak mengubah profil sensori kentang jejari
sebagaimana ditunjukkan dalam keputusan kajian bahawa tidak ada perbezaan yang
signifikan (p<0.05) berbanding kawalan pada semua attribut sensori
(warna, rasa, aroma, keranggupan, rasa berminyak dan kualiti keseluruhan).
Secara keseluruhan, ekstrak Zea mays mampu memanjangkan kestabilan dan
kualiti minyak kelapa dara dan dengan itu mempunyai potensi sebagai sumber baru
antioksidan semula jadi untuk digunakan dalam penggorengan.
Kata kunci: Lemak; menggoreng; minyak kelapa dara; Zea mays
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*Pengarang untuk surat-menyurat; email: mareena@usm.my
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