In vitro reducing power tests of tea polyphenols (Tp), tert-butylhydroquinone (TBHQ), and monoglyceride citrate (MGC) revealed that, at certain concentrations, Tp þ TBHQ displayed a strong reductive capacity. Moreover, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity tests showed that Tp þ TBHQ was effective ( p < 0.05) in quenching DPPH radicals. The effectiveness of Tp þ TBHQ towards the radical-scavenging activity was also found to be increased when their concentrations were increased. The oxidation stability of flaxseed oil (FO) was investigated as a function of time at high temperature, in the absence and presence of antioxidants; the peroxide value (PV) and p-anisidine value of FO were determined as indicators of oxidation at 608C during 20 days. The results revealed that Tp 200 þ TBHQ 100 (subscripts refer to amounts in mg/kg) had noticeable reduction effects on the oxidation (PV and p-anisidine) of FO compared with TBHQ 200 regarding the PV, and when compared with the mixture of TBHQ 100 þ MGC 100 regarding the p-anisidine value. However, according to Rancimat tests, the ternary mixture (Tp 200 þ TBHQ 100 þ MGC 100 ) was found to be more effective in controlling FO oxidation. The induction periods for FO containing Tp 200 þ TBHQ 100 þ MGC 100 , TBHQ 100 þ MGC 100 , and Tp 200 þ TBHQ 100 were 8.305, 6.905, and 6.8020 h, respectively, whereby no significant differences were observed between TBHQ 100 þ MGC 100 and Tp 200 þ TBHQ 100 ( p < 0.025).Practical applications: Flaxseed oil is an unstable vegetable oil due to its high content of PUFA, which are mainly composed of a-linolenic acid (ALA). One effective way to ensure a high quality of lipids and lipidcontaining products, and to prolong their storage time, is to stabilize them by addition of suitable antioxidants. The stabilization of FO will help to increase both its shelf life and to improve its use in different applications. According to recent studies, FO contains many components that are beneficial for human health, especially ALA which can contribute to increasing the DHA and EPA content in the body. FO is believed to provide benefits in the prevention and treatment of heart diseases, arthritis, inflammatory, and autoimmune diseases.

In this covenant of functional foods, the world seeks for new healthier food products with appropriate proportions of bioactive constituents such as fiber, mineral elements, phenols and flavonoids. The doum fruit has good nutritional and pharmaceutical properties; therefore, its incorporation in breads could be beneficial in improving human health. In the current study, partial substitution of wheat flour (WF) with doum fruit flour (DFF) at levels of 5 %, 10 %, 15 % and 20 % were carried out to investigate the dough viscoelastic properties, baking performance, proximate compositions and antioxidant properties of the breads. Partial substitution of WF with DFF increased the water absorption and developing time of dough (P ≤ 0.05), while, the dough extensibility, resistance to extension and the deformation energy were reduced. Bread supplemented with DFF resulted in a reduction in quality in terms of specific loaf volume, conferred softness, hardness, cohesiveness and gumminess to the bread crumbs. DFF up to 15 % could partially replace WF in bread; increase its nutritional value in terms of fiber content and minerals, with only a small depreciation in the bread quality. Sensory evaluation showed that breads supplemented up to 15 % DFF were acceptable to the panelists and there was no significant difference in terms of taste, texture and overall acceptability compared to the control. The incorporation of DFF increased the total phenolic contents, total flavonoids contents and antioxidant properties compared to the control (for both flour and bread).

The interest in application of biocatalysis during natural milk fat flavours development has increased rapidly and lipases have become the most studied group in the development of bovine milk fat flavours. Lipozyme-435, Novozyme-435 and Thermomyces lanuginosus Immobilized (TL-IM) lipases were used to hydrolyze anhydrous milk fat (AMF) and anhydrous buffalo milk fat (ABF) and their volatile flavouring compounds were identified by solid-phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) and then compared at three hydrolysis intervals. Both AMF and ABF after lipolysis produced high amount of butanoic and hexanoic acids and other flavouring compounds; however, highest amount were produced by Lipozyme-435 and Novozyme-435 followed by TL-IM. The hydrolyzed products were assessed by Rancimat-743 for oxidative stability and found both that, for AMF and ABF treated butter oil, Lipozyme-435 and TL-IM were generally more stable compared to Novozyme-435. For both AMF and ABF treated butter oil, Lipozyme-435 was observed to cause no further oxidation consequences which indicates Lipozyme-435 was stable during hydrolysis at 55°C for 24 h.

Dairy products remain valuable components of human diet due to their balanced nutritive value and pleasant flavour. In this study, triacylglycerols (TAGs) from anhydrous milk fats were hydrolysed by Lipozyme-435 and Novozyme-435 and later on analysed by using ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Results revealed that the percentages of TAGs (CN 28-34) and TAGs (CN 36-42) with at least two short-chain fatty acids and with short-and medium-chain fatty acids were respectively decreased after 24 h of enzymatic hydrolysis. On the other hand, TAGs (CN 44-54) with at least two long-chain fatty acids were found to increase in both Lipozyme-435-and Novozyme-435-treated anhydrous milk fat (AMF). Meanwhile, the melting and crystallization profiles of both Lipozyme-435-and Novozyme-435-treated AMF were modified and significantly different when compared with the untreated AMF.

The increasing demand for functional foods has boosted up the food industry to produce fiber-enriched products. In this study, dietary fiber (DF) was isolated from Doum fruit by exploiting the combination of microwave reactor technique and superfine grinding technology. The isolated Doum dietary fiber (DDF) possessed a high content of total dietary fiber, essential minerals and total polyphenols with good antioxidant activity. Biscuits were prepared by substituting wheat flour with DDF at different levels (0, 2.5, 5, 7.5 and 10%) and assessed for dough mixing properties and biscuit quality. The results showed that an increase of DDF in the flour affected physical parameters of biscuits by increasing the biscuits hardness and reducing the diameter, thickness and spread ratio. Supplementation of biscuits with DDF improved the nutritional value in terms of DF contents and essential minerals. Improvement in total phenolic contents (TPC) and antioxidant activities of the biscuits were also noted as a result of DDF supplementation. Biscuits supplemented with 7.5% DDF showed overall better sensorial characteristics. Conclusively, this study has shown that supplementation of wheat flour with DDF improved nutritional profile, antioxidant properties and overall consumer acceptability of biscuits. The present findings will be helpful regarding the development of functional foods enriched with DDF.

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Orthogonal array design (L 9 (3 4 )) was applied to optimize the flaxseed oil (FO) recovery, band g-tocopherols yields and total oxidation value (totox value) using ultrasound-assisted extraction (UAE). The optimized results were then compared with the one extracted by Soxhlet extraction (S.E.) at 8 h. The results revealed that 80.05% FO can be recovered by extraction for 30 min, 30°C and 10:1 solvent/solid ratio by UAE compared to 100% recovery obtained by 8 h, 60°C and 20:1 solvent/liquid ratio by S.E. (taken as reference and standard extraction). band g-tocopherols yield was 40.39 mg/100 g oil at 30 min, 20°C and 10:1 solvent/liquid ratio by UAE compared to 56.37 mg/100 g oil by S.E. Totox value of FO by UAE was lower compared to S.E., which is a promising results for better quality and further processing of the oil. No significant differences were shown between the two extraction methods for fatty acids (p < 0.025). UAE is capable of reducing the financial cost of flaxseed oil extraction, saving time, energy and is also environmentally friendly since very little solvent is used compared to S.E.Practical applications: Flaxseed oil is an unstable vegetable oil due to its high content of polyunsaturated fatty acids (PUFA), which are mainly composed of alpha linolenic acid (ALA). One effective way to ensure a high quality and low oxidation levels of lipids and lipid containing products is to use efficient and rapid method for the extraction.

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