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

Received: 28 January 2011/Accepted: 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

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*Corresponding author; email: wawm@ukm.my