Quality Indices, Phenolic Compounds and Sensory Evaluation of Flavored Olive Oil.

In this study, the effect of adding some aromatic plants (garlic, rosemary, thyme, and hot-red pepper) on the quality and organoleptic properties of flavored olive oil extracted from the olive fruits Maraqi variety are studied after adding aromatic plants at a concentration of 2%. Acidity, peroxide value, K232, K270, sensorial attributes, oxidative stability, and phenolic contents had been monitored. Also, phenolic compounds are identified in the flavored and unflavored olive oil samples. These results demonstrated that the aromatic plant had enhanced the flavored olive oil stability; the levels of addition of aromatic plants could be distinguished by the taster's sensory attributes of flavored olive oil. As the plan of the experiment includes process preparation and consumer preference, it is possible to apply the obtained results to the production of flavored olive oil. The producers will gain a new product with more added values due to the nutritional and antioxidant strength of the aromatic plants.

Synthesis and Application of a New Amphiphilic Antioxidant.

A new amphiphilic antioxidant (tannyl stearate) derived from reaction of tannic acid with stearic acid was synthesized in order to improve tannic acid solubility in lipid materials. This reaction gives many products having different degree of esterification (tannyl mono, di, tri, tetra, penta, hexa, hepta……stearate) which were separated using silica gel column chromatography and tentative identification was carried out using thin layer chromatography (TLC). The intrinsic viscosities (η) were used to differentiate between the different molecular weight of the produced esters1). Tannyl penta stearate is assumed to be the most suitable amphiphilic antioxidant derivative, where those derivatives with less degree of esterification would be less soluble in fat, and those of higher degree of esterification would exhaust more hydroxyl group that cause decreases of antioxidant activity. The structure of tannyl penta stearate was approved depending on its chemical analysis and spectral data (IR, H1 NMR,). The emulsification power of tannyl penta stearate was then determined according to method described by El-Sukkary et al.2), in order to prove its amphiphilic property. Then tannyl penta stearate was tested for its antioxidant and radical scavenging activities in three different manners, those are, lipid oxidation in sunflower oil using Rancimat, (DPPH) free radical scavenging and total antioxidant activity. {Pure tannic acid (T), butylhydroxyanisol (BHA) and butylhydroxytoluene (BHT) were used as reference antioxidant radical saving compounds}. Then tannyl penta stearate was added to sunflower oil, frying process was carried out and all physicochemical parameters of the oil were considered, and compared to other reference antioxidant in order to study the effect of this new antioxidant toward oil stability. Acute oral toxicity of the tannyl penta stearate was carried out using albino mice of 21-25 g body weight to determine its safety according to the method described by Goodman et al.3). Also liver and kidney functions of those mice were checked. Thus it could be concluded that the addition of tannyl penta stearate to frying oils offers a good protection against oxidation. The effectiveness of tannyl penta stearate as lipid antioxidant has been attributed mainly to its stability at high temperature. And according to acute lethal toxicity test tannyl penta stearate was found to be a safe compound that can be used as food additive.

Utilization of Stearic acid Extracted from Olive Pomace for Production of Triazoles, Thiadiazoles and Thiadiazines Derivatives of Potential Biological Activities.

Olive Pomace was firstly dried, then pomace olive oil was extracted, and the obtained oil was hydrolyzed to produce glycerol and mixture of fatty acids. Fatty acids mixture was separated, this mixture was then cooled, where the all saturated fatty acids were solidified, and then they were filtered off. These saturated fatty acids were identified by GC mass after esterification, and were identified as stearic, palmitic and myristic acids. Stearic acid was extracted using supercritical CO2 extractor. The stearic acid was confirmed by means of GC mass after its esterification, and it was used as starting material for preparation of a variety of heterocyclic compounds, which were then tested for their antimicrobial activities. Thus the long-chain fatty acid hydrazide (2) was prepared from the corresponding long-chain fatty ester with hydrazine hydrate. Reacting 2 with phenyl isothiocyanate afforded the corresponding thiosemicarbazide 4. The later 4 underwent intramolecular cyclization in basic medium, and gave the s-triazole derivative 5, which was methylated and afforded 3-heptadecanyl-5-(methylthio)-4-phenyl-4H-1,3,4-triazole (7), which was then treated with hydrazine hydrate and afforded the corresponding 1-(5-heptadecanyl-4-phenyl-4H-1,2,4-triazol-3-yl) hydrazine (8).On the other hand, thiosemicarbazide 4 underwent intramolecular cyclization in acid medium and afforded the corresponding thiadiazole derivative 6.Treatment of thiosemicarbazide 4 with ethyl chloro(arylhydrazono) acetate derivatives 9a-b, furnished a single product 13 (Scheme 6). Similarly, when the thiosemicarbazide 4 was treated with the phenylcarbamoylarylhydrazonyl chloride 10a-c, it afforded (3-Aryl-N-5-(phenylcarbamoyl)-1,3,4-thiadiazol-2(3H)-ylidene)octadecanehydrazide 15a-c (Scheme 7). Also the reaction of thiosemicarbazide 4 with 2-oxo-N-arylpropanehydrazonoyl chlorides 11a-c and N-phenylbenzohydrazonoyl chloride 11d gave the corresponding thiadiazole derivatives 16a-d as shown in Scheme 8. A solution of thiosemicarbazide 4 was treated with the haloketones 17a-c, afforded the thiadiazine derivatives 20a-c, as shown in Scheme 9. Analogously, the thiosemicarbazide 4 was reacted with α-haloketones 21a-b and afforded the corresponding products 22a-b (Scheme 9). The structure elucidation of all synthesized compounds is based on the elemental analysis and spectral data (IR, 1H NMR, 13C NMR and MS).

Safety evaluation of olive phenolic compounds as natural antioxidants.

Free and total polyphenolic compounds were extracted from the fruits and leaves of the Picual cultivar. The safety limits of these compounds were recognized by measuring the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and the levels of high-density lipoprotein (HDL) cholesterol and total lipids of rat serum. The free and total phenolic compounds (400, 800, and 1600 ppm) and butylated hydroxy toluene (BHT) (200 ppm) were daily ingested for 7 weeks. The administration of olive total and free phenolic compounds at 400 and 800 ppm did not cause any significant changes on ALT and AST activities and serum total lipids. These compounds at 1600 ppm caused significant increase in ALT and AST activities and the content of total lipids. Both olive phenolic compounds were superior to that of BHT in increasing HDL-cholesterol level. Nutritional experiments demonstrated that BHT at 200 ppm caused an enlargement in the kidney and liver of the rat compared with the administration of total and free olive phenolic compounds at 1200 and 1600 ppm. Microscopical examination of kidney and liver tissues of rats administered free and total phenolic compounds at 1200 ppm had the same histological character as that of control rats, while the administration of BHT (200 ppm) and phenolic compounds (1600 ppm) induced severe damage to the tissues of the rat kidney and liver.