Sabah, Cinar,&Celik (2007)suggested

Sabah, Cinar,&Celik (2007)suggested thatb-carotene adsorption onto sepiolite is also physical. On the other hand, according
to Khoo, Morsingh,&Liew (1979), b-carotene adsorption onto
different commercial bleaching earths is not purely physical.
Later, other works found thatb-carotene adsorption onto acid
activated bleaching earth (Sarier&Guler, 1988) and onto silica
gel (Ahmad, Chan, Shukor,&Mashitah, 2009) was controlled by
chemisorption.
It is well accepted that there is no correlation between the bcarotene content after bleaching and the palm oil final color
(Dijkstra&Segers, 2007; Fraser&Frankl, 1981; Maclellan, 1983).
Some studies suggest that in thefinished oil, the color is mostly due
to high molecular weight (HMW) compounds derived from
oxidation reactions, especially in the case of carotenoids (Fraser&
Frankl, 1981). Also, aggressive bleaching conditions, as excessive
temperatures or time process or both, lead to darker final colors
(Maclellan, 1983).
Recently, there are several research groups studyingb-carotene oxidation in lipid/organic systems (Benevides, Veloso,
Pereira,&de Andrade, 2011; Bosser, Paplorey,&Belin, 1995;
Rodriguez&Rodriguez-Amaya, 2007; Wache, Bosser-DeRatuld,
Lhuguenot, &Belin, 2003; Zeb, 2012; Zeb&Murkovic, 2013a,
2013b)concerningb-carotene antioxidant activity, off-flavor
compounds formation and synthesis. However, there is a lack
in the literature in works concerning the b-carotene pathways
during refining practices and its importance in the quality of fully
refined oils. In this context, the goal of this work was to study the
effect of the type of bleaching earth used during bleaching on the
color of fully refined palm oil. Moreover, a hypothesis is proposed
to explain how the type of bleaching earth can affect the
oxidation pathways.
2. Material and methods
2.1. Oil characterization
Standard quality parameters, including free fatty acids (FFA)
content, color, carotene content, deterioration of bleachability index (DOBI) and element content, were analyzed for crude, bleached
and full refined palm oil samples.
2.1.1. Color
The sample color was determined according to the AOCS Official
Method Cc 13e-92, using a Lovibond Tintometer Color Scale at
70


C, ensuring that color was determined in a completely
melted sample. Analyses were carried out using 500 ¼(133.4 mm)
glass cells. In the cases of crude palm oil samples, the color was
darker than scale in a 5
00 ¼glass cell and a 1
00
(25.4 mm) was used
(AOCS, 1998).
2.1.2. Free Fatty Acids (FFA)
Free Fatty Acids content (FFA) was determined according to the
AOCS Official Method Ca 5-40, by titration. Results were expressed
as percentage of palmitic acid (C16:0, MW ¼ 256 g/mol)
(AOCS, 1998).
2.1.3. Deterioration of the bleachability index (DOBI)
The deterioration of bleachability index (DOBI) was measured
using a UVevis spectrophotometer. This index corresponds to the
ratio of the spectrophotometric absorbance at 446 nm (nonoxidized carotenes maximum) to the absorbance at 268 nm
(oxidized carotenes maximum).
About 0.1 mg of completely molten and homogenized oil is
diluted in 25 mL of iso-octane. Absorbencies are measured at
268 nm and 446 nm. The DOBI value is obtained by Eq.(1)

Hasil (Bahasa Indonesia) 1:

Sabah, Cinar, & Celik (2007) thatb-karoten disarankan adsorpsi ke sepiolite ini juga fisik. Di sisi lain, menurutuntuk Khoo, Morsingh, & Liew (1979), b-karoten adsorpsi keberbeda komersial bleaching Earth bukanlah fisik semata-mata.Kemudian, karya-karya lain menemukan thatb-karoten adsorpsi ke asamdiaktifkan bleaching bumi (Sarier & Guler, 1988) dan ke silikagel (Ahmad, Chan, Shukor, & Mashitah, 2009) dikendalikan olehchemisorption.Itu juga diterima bahwa ada tidak ada korelasi antara konten bcarotene setelah pemutihan dan warna akhir minyak sawit(Dijkstra & Segers, 2007; Fraser & Frankl, 1981; Maclellan, 1983).Beberapa studi menunjukkan bahwa dalam minyak thefinished, warna sebagian besar karenauntuk senyawa berat molekul tinggi (HMW) yang berasal darireaksi oksidasi, terutama dalam hal karotenoid (Fraser &Frankl, 1981). Juga, agresif pemutihan kondisi, sebagai berlebihansuhu atau waktu proses, atau keduanya, mengarah ke gelap warna akhir(Maclellan, 1983).Baru-baru ini, ada beberapa penelitian kelompok studyingb-karoten oksidasi lemak organik sistem (Benevides, Veloso,Pereira, & de Andrade, 2011; Bosser, Paplorey & Belin, 1995;Rodriguez & Rodriguez-Amaya, 2007; Wache, Bosser-DeRatuld,LHUGUENOT & Belin, 2003; Zeb, 2012; Zeb & Murkovic, 2013a,2013b) concerningb-karoten antioksidan kegiatan, mati rasasenyawa pembentukan dan sintesis. Namun, ada kekurangandalam literatur dalam karya-karya mengenai jalur b-karotenselama selama penyulingan praktek dan kepentingannya dalam kualitas penuhdimurnikan minyak. Dalam konteks ini, tujuan karya ini adalah untuk mempelajariefek pemutihan bumi digunakan selama pemutihan pada jenis yangwarna sepenuhnya halus minyak sawit. Selain itu, sebuah hipotesis yang diajukanuntuk menjelaskan bagaimana jenis pemutihan bumi dapat mempengaruhijalur oksidasi.2. bahan dan metode2.1. minyak karakterisasiParameter standar mutu, termasuk asam lemak bebas (FFA)konten, warna, karoten konten, kerusakan bleachability index (DOBI) dan elemen konten, dianalisis untuk mentah, dikelantangdan penuh halus minyak sawit sampel.2.1.1. warnaSampel warna ditentukan menurut AOCS resmiMetode Cc 13e-92, menggunakan skala warna Tintometer Lovibond di70
C, memastikan bahwa warna ditetapkan dalam benar-benarcontoh meleleh. Analisis dilakukan menggunakan 500 ¼(133.4 mm)sel kaca. Dalam kasus sampel minyak sawit mentah, warna itulebih gelap dari skala dalam 500 ¼glass sel dan 100(25.4 mm) digunakan(AOCS, 1998).2.1.2. free Fatty Acid (FFA)Isi asam lemak bebas (FFA) ditentukan menurutAOCS resmi metode Ca 5-40, oleh titrasi. Hasil diungkapkansebagai persentase dari asam palmitat (C16:0, MW ¼ 256 g/mol)(AOCS, 1998).2.1.3. kemerosotan indeks bleachability (DOBI)Kerusakan indeks bleachability (DOBI) diukurusing a UVevis spectrophotometer. This index corresponds to theratio of the spectrophotometric absorbance at 446 nm (nonoxidized carotenes maximum) to the absorbance at 268 nm(oxidized carotenes maximum).About 0.1 mg of completely molten and homogenized oil isdiluted in 25 mL of iso-octane. Absorbencies are measured at268 nm and 446 nm. The DOBI value is obtained by Eq.(1)