Malaysian Journal of Analytical Sciences Vol 20 No 6 (2016): 1373 - 1381

DOI: http://dx.doi.org/10.17576/mjas-2016-2006-16

 

 

 

EFFECT OF HEAT TREATMENTS ON THE YIELD, QUALITY AND STORAGE STABILITY OF OIL EXTRACTED FROM PALM FRUITS

 

(Kesan Rawatan Haba Terhadap Peratus Pengekstrakan Minyak, Kualiti dan Kestabilan Semasa Penyimpanan Minyak yang Diekstrak Daripada Buah Kelapa Sawit)

 

Hasimah Kasmin^{1, 2}, Azwan Mat Lazim², Roila Awang¹*

 

¹Engineering & Processing Research Division,

Malaysian Palm Oil Board, No. 6, Persiaran Institusi, Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia

²School of Chemical Sciences and Food Technology, Faculty of Science and Technology,

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

 

*Corresponding author: roila@mpob.gov.my

 

 

Received: 17 August 2015; Accepted: 29 August 2016

 

 

Abstract

This paper presents the impact of heat treatments on the yield and quality of the palm oil using solvent extraction techniques. Heating temperature range from 70 to 90 °C and heating time range from 30 to 90 min were studied. The quality parameters measured were free fatty acids (FFA), deterioration of bleaching index (DOBI), carotene content, oxidative stability and fatty acid composition of the oil. These parameters were used to determine CPO quality which has been stored for 3 months. It was found that the yield significantly increased with the increasing of heating temperature and time. The optimum parameter was achieved with heating temperature of 90 °C and heating time of 60 min via wet heating. Optimum oil yield obtained was 24% with 0.93% FFA content, 6.10 DOBI, 938.42 ppm carotene content and oxidative stability of 26.87 hours. Fatty acid composition (FAC) of oil extracted showed a reduction in unsaturated fatty acids as the heating duration increased. After 3 months of storage, 60 min of heating time via wet heating process was recorded the lowest increment of FFA (1.32%) and low reduction of DOBI value (0.41). However, carotene content gave the highest loss with 113.54 ppm towards the end of the storage.

 

Keywords:  crude palm oil, heat treatments, oil yield, oil quality, storage stability

 

Abstrak

Kajian ini bertujuan untuk menganalisis kesan rawatan haba semasa pensterilan ke atas peratus pengekstrakan minyak dan kualiti minyak sawit mentah (MSM) dengan menggunakan pelarut bagi mengekstrak MSM. Suhu dan masa pensterilan yang berlainan telah digunakan bagi mengekstrak MSM iaitu suhu pensterilan dari 70 hingga 90 °C manakala masa pensterilan dari 30 hingga 90 min. Kesan rawatan haba ke atas peratus pengekstrakan minyak telah dijalankan. Kualiti MSM yang diekstrak iaitu asid lemak bebas (ALB), indeks pemerosotan terhadap pelunturan (DOBI), kandungan karotena, kestabilan oksidatif dan komposisi asid lemak yang telah dicirikan. Parameter ini digunakan untuk menentukan kualiti MSM yang telah disimpan selama 3 bulan. Hasil kajian mendapati peratus pengekstrakan minyak meningkat secara signifikan dengan kenaikkan kesan suhu dan masa.  Hasil optimum pada tahap maksimum iaitu sebanyak 24% telah dicapai pada suhu pensterilan 90 °C dan masa pensterilan 60 min dengan menggunakan pemanasan basah. Kualiti minyak pula menunjukkan kandungan ALB sebanyak 0.93%, DOBI sebanyak 6.10, kandungan karotena sebanyak 938.42 ppm dan kestabilan oksidatif selama 26.87 jam. Selepas 3 bulan penyimpanan, masa pemanasan selama 60 min menggunakan pemanasan basah telah menunjukkan peningkatan kandungan ALB dan penurunan bacaan DOBI yang paling rendah iaitu masing – masing 1.32% dan 0.41. Namun, kandungan karotena didapati merosot paling tinggi iaitu sebanyak 113.54 ppm.

 

Kata kunci:    minyak sawit mentah, rawatan haba, peratus pengekstrakan minyak, kualiti minyak, kestabilan minyak

 

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