8342937107

Pertanika 14(1). 53-57 (1991)

Effects of Ascorbyl Palmitate and Silicone on Frying Performance of Palm Olein

KAMSLAH 1BRAHIM¹, M. A. AUGUSTIN¹ and A.S.H. ONG⁸

¹ Faculty of Food Science and Biotechnolog) , l >niversiti Perlanian Malaysia

43400 L I PM Serdang_y Selangor Danii Ehsan, Malaysia

² Palm Oil Research Institute of Malaysia P.O. Box 10620, 50720 Kuala Lumpur, Malaysia.

KeyworcŁs: Frying performance, palm olein, banana slices, silicone, ascorbyl palmitate.

ABSTRAK

Perubahan kualiti dałam minyak Majta sawil olein yang digunakan -unluk jtenggorengan tak ber ter u san kerepek pisangselama 5 jamsehań unluk 4 hari bertumtandikaji. Penilaian % komponen ftolar, nil anod ni, nilaiasid, nisbah C!8:2/C 16:0 dan % Cl8:2 tertinggal menunjukkan bahawapenambuhan 2 mgkg ¹ silikon secarapersendińan dan penambahan 200 mgkg~^l as kor kil palmitat (AP) bersa ma dengan 2 mgkg ¹ silikon kejtada minyak Majta sawit merendahkan dengan bererti (p < 0.05) kadarkerosakan minyak semasa jtenggorengan. Penambahan 200 mgkg ¹ AP secarapersendirian kejtada minyak tidak ada kesan bererti (P> 0.05) keatas kerosakan minyak tetajńdidajtati bahawa nilaiuntuk perubahan dałam % komponen ftolar_y nilai iodin, nilaiasid, nisbah, nisbah Cl 8:2/Cl 6:0 dan % Cl 8:2 ferii nggal ada lab secara umumlebih rendah j i ka di band ingkan dengan minyak tanjta bahan jt en araba h. Perhubungan linear didajtati dian tara % kom/tonen ftolar dan nilai iodin dan diantara nilai iodin dan nisbah C18:2/Cl 6:0 dałam sistem penggorenga n yangdikaji.

ABSTRACT

The (fuality changes in palm olein used jor the intermittent frying of banana slices over a 5 h intewal per day for 4 conseculinedays wasstudied. Assessmentof % ftolarcomponents, iodinevalue_t acid value_t C18:2/C16:0 ratio and % (.18:2 remainingindicated thai theaddilion oj 2 mgkg ¹ silicone alone and that oj 200 mgkg'¹ ascorbyl palmitate [AP) plus 2 mgkg'¹ silicone to jtalm olein signi/icanlly reduced (p < 0.05) the ratę oj oil deterioralion during frying. The addilion of200 mgkg ¹ AP alone to jtalm olein did not have a signiftcant effect (ft > 0.05) on oil deleriorufion although it was euident that therałues jor changes in % ftolar components, iodineitalue, acidualue, Cl8:2/Cl 6:0 ratio and % Cl8:2 remainingin the oil weregenerally less than those in oil without additiues. Linear relationships werefou nd between % ftolar components and iodineitalue and between iodineitalue and Cl8:2/Cl6:0in the frying Systems studied

INTRODUCTION

The deterioration offats under frying conditions hasbeen studied by many workers (Krishnamurthy, 1965; Roth and Rock 1972, (.hang et al. 1978; Fritsch 1981;Stevenson et al. 1984). Deterioration of the frying dii results in the accumulation of numerous decomposition products which affect the functional, sensoYy and nutritkmal ąuality of the oil. Thequalityof thefricd food isalsoaffected.

Thereisinterest in the useofvariousmethods for extending the frying lifeofan oil. The impetus has been the economic gains that wotild be rea-lized wiih extension of the useful frying life of the oil. Various workers have studied the effects of a variety of additives and treatments for extending fry-life. Martin (1953) and Babayan (1961) have patentson the useofmenthyl silicone for protect-ingoil against oxidative deterioration and raising the smoke point of the oil. Freeman et al (1973) showed that silicones could greatly increase the oxidative sta bili ty of oils at high temperatures. Frankel etal (1985) found that addilion ofmethyl silicone significantly improved cooking oil performance. Ascorbyl palmitate (AP) which waslisted as a substance Generally Regarded asSafe(GRAS) in 1982 was found to be effect ive for retarding de-