Sains Malaysiana 43(5)(2014):
723–731
Sebatian Meruap, Ciri Fizikokimia dan Penilaian Sensori Tiga
Jenis Santan
dalam Pasaran Malaysia
(Volatile Compounds, Physico-chemical Characteristics and Sensory
Evaluation
of Three Types of Coconut Milk in Malaysian Market)
LIM SENG JOE, WAN AIDA WAN MUSTAPHA* & MOHAMAD YUSOF MASKAT
Pusat Pengajian Sains Kimia dan Teknologi Makanan. Fakulti
Sains dan Teknologi
Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
Diserahkan: 28 Januari 2011/Diterima: 9 September 2013
ABSTRAK
Kajian ini dijalankan untuk membandingkan profil sebatian meruap,
ciri fizikokimia dan penilaian sensori antara santan segar, santan UHT dan
santan serbuk. Kaedah mikroekstraksi fasa pepejal (SPME) digunakan untuk
mengekstrak sebatian meruap dalam sampel dan dianalisis menggunakan
kromatografi gas-spektrometer jisim (GC-MS). Analisis profil sebatian meruap
menunjukkan santan segar mempunyai tujuh sebatian meruap manakala santan UHT dan
santan serbuk masing-masing mempunyai empat dan lima sebatian meruap. Sebatian
meruap utama yang terdapat di dalam santan adalah delta-lakton. Santan segar
mengandungi kandungan protein (2.35 ± 0.17%), lemak (25.57 ± 1.56%) dan abu
(0.82 ± 0.03%) tertinggi secara bererti (p<0.05) manakala santan serbuk (berat basah) mengandungi
kandungan lembapan (78.77 ± 0.37%) dan karbohidrat (8.06 ± 0.41%) tertinggi
secara bererti (p<0.05) dan asid lemak bebas (0.43 ± 0.03%) terendah
secara bererti (p<0.05). Bacaan pH menunjukkan bahawa santan serbuk
(5.90 ± 0.11) bersifat lebih berasid secara bererti (p<0.05)
berbanding dengan santan segar (6.16 ± 0.02) dan santan UHT (6.17 ± 0.04%). Bagi
analisis kelikatan, santan UHT mempunyai kelikatan tertinggi, kerana
telah ditambah dengan karagenan dan berbeza secara bererti (p<0.05)
dengan santan segar dan santan serbuk. Melalui ujian L*, a*, b*, didapati
bahawa warna bagi santan UHT dan santan serbuk adalah lebih cerah dan
putih secara bererti (p<0.05) berbanding santan segar. Penilaian sensori
menunjukkan bahawa santan segar mempunyai min skor darjah kesukaan tertinggi
bagi aroma kelapa, perisa asing, aroma keseluruhan dan penerimaan keseluruhan.
Santan UHT pula mempunyai min skor darjah kesukaan tertinggi dari segi warna
dan kelikatan.
Kata kunci: Ciri fizikokimia; penilaian sensori; santan segar;
santan serbuk; santan UHT; sebatian meruap
ABSTRACT
This research was done to compare the volatile compounds profile,
physico-chemical characteristics and sensory evaluation between fresh, UHT and
powdered coconut milk. Solid phase microextraction method (SPME) was used to extract
volatile compounds from samples for analysis using gas chromatography-mass
spectrometry (GC-MS).
Volatile compounds profile analysis showed that there were seven, four and five
volatile compounds in fresh, UHT and powdered coconut milk, respectively.
The main volatile compounds in coconut milk were delta-lactones. Fresh coconut
milk contains the highest (p<0.05)
protein (2.35 ± 0.17%), fat (25.57 ± 1.56%) and ash content (0.82 ± 0.03%),
while powdered coconut milk (wet weight) contains the highest (p<0.05)
moisture (78.77 ± 0.37%) and carbohydrate (8.06 ± 0.41%) content and lowest (p<0.05)
free fatty acid content (0.43 ± 0.03%). The pH of powdered coconut milk (5.90 ±
0.11) was significantly (p<0.05) more acidic compared to that of
fresh (6.16 ± 0.02) and UHT coconut milk (6.17 ± 0.04%). Viscosity
analysis showed that UHT coconut milk has the highest viscosity due
to the addition of carrageenan and was significantly different (p<0.05)
from fresh and powdered coconut milk. The colour of UHT and powdered coconut
milk were significantly (p<0.05) lighter and whiter compared to that
of fresh coconut milk. Sensory evaluation shows that fresh coconut milk has the
highest degree of likeness in terms of coconut aroma, off-flavours, overall
aroma and overall acceptance. The UHT coconut milk has the highest degree of
likeness in terms of colour and viscosity.
Keywords: Fresh coconut
milk; physicochemical characteristics; powdered coconut milk; sensory
evaluation; UHT coconut milk; volatile compound
RUJUKAN
Bahruddin, S., Cheng, W.L., Md Sariff, J., Boey, P.L.,
Abdussalam, S.M.A., Wan, T.W. & Muhammad Idiris, S. 2007. Determination of
free fatty acids in palm oil samples using non-aqueous flow injection
titrimetric method. Food Chemistry 102: 1407-1414.
Belewu, M.A. & Belewu, K.Y. 2007. Comparative
physico-chemical evaluation of tiger-nut, soybean and coconut milk sources. International
Journal of Agriculture & Biology 9(5): 785-787.
IUPAC. 1997. Compendium of Chemical Terminology. 2nd
ed. (the “Gold Book”). Oxford: Blackwell Scientific Publications.
http://goldbook.iupac.org . Accessed on 5 April 2010.
Jangchud, K., Puchakawimol, P. & Jangchud, A. 2007.
Quality changes of burnt aromatic coconut during 28-day storage in different
packages. LWT - Food Science and Technology 40: 1232-1239.
Murano, P.S. 2003. Understanding Food Science and
Technology. Belmont, CA: Thomson / Wadsworth.
Narataruksa, P., Pichitvittayakarn, W., Heggs, P.J. &
Tia, S. 2010. Fouling behavior of coconut milk at pasteurization temperatures. Applied
Thermal Engineering 30: 1387-1395.
Nielsen, S.S. 2003. Food Analysis. Ed. ke-3. New York:
Kluwer Academic / Plenum Publishers.
Peamprasart, T. & Chiewchan, N. 2006. Effect of fat
content and preheat treatment on the apparent viscosity of coconut milk after
homogenization. Journal of Food Engineering 77: 653-658.
Seow, C.C. & Gwee, C.N. 1997. Coconut milk: Chemistry
and technology. International Journal of Food Science and Technology 32(3):
189-201.
Simuang, J., Chiewchan, N. & Tansakul, A. 2004. Effects
of fat content and temperature on the apparent viscosity of coconut milk. Journal
of Food Engineering 64: 193-197.
Srinivasan, M., Singh, H. & Munro, P.A. 2002. Formation
and stability of sodium caseinate emulsions: Influence of retorting (121°C for
15 min) before or after emulsification. Food Hydrocolloids 16: 153-160.
Tansakul, A. & Chaisawang, P. 2006. Thermophysical
properties of coconut milk. Journal of Food Engineering 73: 276-280.
Tangsuphoom, N. & Coupland, J.N. 2008. Effect of
surface-active stabilizers on the microstructure and stability of coconut milk
emulsions. Food Hydrocolloids 22: 1233-1242.
Wright, J. 1992. Synthetic Flavouring Materials. London:
Bush Boake Allen.
*Pengarang
untuk surat-menyurat; email: wawm@ukm.my
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