Quality Assessment of Deodorizer Distillate Produced in Edible Oil Industries

Saba Naz, . (2015) Quality Assessment of Deodorizer Distillate Produced in Edible Oil Industries. Doctoral thesis, UNIVERSITY OF SINDH, JAMSHORO.

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Deodorizer distillate (DD) is an important by-product obtained during deodorization process in the edible oil industries. It is a complex mixture of many health beneficial constituents like phytosterols, tocopherols and squalene. DD is not only considered as a waste material because it is a rich source of naturally occurring bioactive and nutritive compounds that make it economically valued. Owing to the intrinsic nature of DD the project was carried out for determination of these vital components by different analytical techniques as well as their application. The present work is divided into six parts. In first part of study deodorizer distillates of canola and sunflower oil were studied for their chemical characterization. Tocopherols, sterols, hydrocarbons and fatty acid composition were determined by Gas chromatography Mass spectrometry (GC-MS). Results indicated that deodorizer distillates of canola oil (DDCLO) studied had higher saponification value in the range of (164.24-175.78 mg/g) and all deodorizer distillate of sunflower oil (DDSFO) having high iodine value (126.19-127.12 g/100g). Peroxide value and free fatty acids were present in the range between 6.95-8.94 mEq/Kg and 35.66-54.38 g/100g in DDSFO and DDCLO samples, respectively. Oleic acid (49.29- 51.14 g/100g) and linolenic acid (6.18-7.45 g/100g) was significantly greater in DDCLO samples. Conversely, DDSFO contained concentrated amount of linoleic acid (52.78- 53.26 g/100g). Tocopherols and hydrocarbons were significantly higher in all DDSFO samples while, sterols were dominant in DDCLO samples. GC-MS provided excellent results for simultaneous determination of tocopherols, sterols, hydrocarbons and fatty acid composition of deodorizer distillates of canola and sunflower oil. Page In second part the changes of total and individual tocopherols were investigated during different sunflower oil processing stages by reverse-phase high-performance liquid chromatography. The results revealed that the levels of total and individual tocopherol content were decreased during the neutralization, bleaching, and deodorization processes. The overall loss of total tocopherols during these stages was found to be 37.9%, although the general reduction trend of delta (?), gamma (?), and alpha (?) tocopherols is very similar during neutralization (35.3%), bleaching (38.3%) and deodorization (37.8%). Deodorizer distillates were also analyzed and were found to be rich with tocopherols content (29348.24 µg/ml). The results of the study indicated that most parts of the tocopherols are wasted during deodorization processing. In third part a simple, rapid, economical, and environmentally friendly analytical method was developed for the quantitative assessment of free fatty acids (FFAs) present in deodorizer distillates and crude oils by single bounce-attenuated total reflectance- FTIR spectroscopy. Partial least squares was applied for the calibration model based on the peak region of the carbonyl group (C=O) from 1726 to 1664 cm-1 associated with the FFAs. The proposed method totally avoided the use of organic solvents or costly standards and could be applied easily in the oil processing industry. The accuracy of the method was checked by comparison to a conventional standard American Oil Chemists' Society (AOCS) titrimetric procedure, which provided good correlation (R = 0.99980), with an SD of ±0.05%. Therefore, the proposed method could be used as an alternate to the AOCS titrimetric method for the quantitative determination of FFAs especially in deodorizer distillates. In fourth part of study a simple GC-MS was developed for the separation, detection and quantification of different components present in the deodorizer distillate in a very short analysis time of 18 min. A simple saponification procedure without derivatization was used for their analysis followed by GC-MS analysis. Phytosterols concentration (21.27-25.53%) was the most abundant in canola and palm distillate samples whereas; squalene and tocopherol were present in concentration ranges of 2.89- 13.21% and 1.29-5.81%, respectively. In final approach a new alginic acid supported tin catalyst (Sn-Alg) was successfully synthesized, characterized and applied for free fatty acid esterification in corn deodorizer distillate (CDD). The effects of reaction time, methanol to fatty acid ratio and catalyst concentration were optimized using myristic acid standard. The best reaction conditions were found to be 4% catalyst amount, 1:12 myristic acid to methanol mole ratio and 2 hours reaction time produced around 98.7% fatty acid methyl ester at a fixed temperature 65°C. Moreover, the catalyst could be repeatedly employed for at least nine cycles and still retained around 90% of its original activity which confirmed its excellent operating stability. The optimized conditions were also used to esterify CDD to give 96.8% methyl ester conversion. These results clearly indicate that the Sn-Alg catalyst is economic, eco-friendly, and promising for biodiesel production from low-cost feedstocks and may find wide applications.

Item Type: Thesis (Doctoral)
Uncontrolled Keywords: Quality.Deodorizer ,Edible,Industries
Subjects: Q Science > QD Chemistry
Depositing User: Ms Maryam Saeed
Date Deposited: 26 Oct 2017 07:15
Last Modified: 26 Oct 2017 07:15
URI: http://eprints.hec.gov.pk/id/eprint/6858

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