Assessment of transesterified palm olein and Moringa oleifera oil blends as vanaspati substitutes

Selective pressurized hot water extraction of nutritious macro-nutrients vs. micro-nutrients in Moringa oleifera leaves-a chemometric approach

Moringa oleifera leaves are widely used in traditional medicine as a food supplement because they are high in essential and nutritious content. Pressurized hot water extraction (PHWE), which is a green approach, was used for the recovery of the macro-nutrient and micro-nutrient elements from dried leaf powder of Moringa oleifera. In this study, response surface methodology was applied to assess the influence of temperature (50-200 °C) and time (5-60 min) on the extractability pattern of macro-nutrient and micro-nutrient elements from the leaves of Moringa oleifera when processed by PHWE. The quantification of macro-nutrient elements such as Ca, K and Mg and micro-nutrient elements like Al, Co, Cr, Cu, Fe, Ni and Zn from the leaves was determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). Obtained results revealed that the extraction of macro-nutrient elements from the Moringa oleifera leaves was enhanced by increasing the extraction time more than the extraction temperature. On the contrary, the amounts of extractable micro-nutrient elements were increased by increasing the extraction temperature. Hence, the recovery for macro-nutrient elements ranged from 88 to 98% while for micro-nutrients it ranged from 21 to 46%. This implies that macro-nutrient elements are extracted with relatively high selectivity in relation to micro-nutrient elements in Moringa dried leaf powder using the PHWE technique.

Improvement in nutritional quality and thermal stability of palm olein blended with macadamia oil for deep-fat frying application

This study aimed to investigate the suitability of refined bleached deodorized palm olein oil (RBD POO) and Macadamia integrifolia oil (MO) blend as deep-fat frying substitute. Oxidative and hydrolytic stability of MO, POO and blends during 15 days of storage under accelerated oxidation condition (65 °C ± 1) studied by assessing free fatty acids (FFA), peroxide (PV), anisidine (AV) and TOTOX (TV) values. Blends formulated with POO: MO at 100:0, 75:25, 50:50, 25:75 and 0:100. Blending significantly affected the fatty acid profile, smoke point, FFA, PV, AV and TV of all samples (p < 0.05). Both independent variables (storage time and type of oil) and their interaction had significant effect on FFA, PV, AV and TV (p < 0.05). On day 15, the highest and the lowest FFA observed for MO and POO, respectively. The significant difference between FFA of MO and POO before incubation and day 15th was due to role of refining process in elimination of initial FFAs from POO. Results of PV, AV and TV showed that the highest and least changes were presented by POO and MO, respectively. Oil blends containing higher proportions of MO with a great percentage of monounsaturated and less polyunsaturated fats were more stable against oxidation. Also, presence of antioxidants played significant role against MO oxidation. From this research, blending POO with MO improved induction period of the blends and inhibited primary and secondary oxidation products formation. Blend 25:75 met the qualitative and nutritional criteria and suggested for formulation of a functional oxidative stable frying medium.

Omega-3 fatty acids, phenolic compounds and antioxidant characteristics of chia oil supplemented margarine

Background

Chia (Salvia hispanica L.) is known as power house of omega fatty acids which has great health benefits. It contains up to 78% linolenic acid (ω-3) and 18% linoleic acid (ω-6), which could be a great source of omega-3 fatty acids for functional foods. Therefore, in this study, margarines were prepared with supplementation of different concentrations of chia oil to enhance omega-3 fatty acids, antioxidant characteristics and oxidative stability of the product.

Methods

Margarines were formulated from non-hydrogenated palm oil, palm kernel and butter. Margarines were supplemented with 5, 10, 15 and 20% chia oil (T₁, T₂, T₃ and T₄), respectively. Margarine without any addition of chia oil was kept as control. Margarine samples were stored at 5 °C for a period of 90 days. Physico-chemical (fat, moisture, refractive index, melting point, solid fat index, fatty acids profile, total phenolic contents, DPPH free radical scavenging activity, free fatty acids and peroxide value) and sensory characteristics were studied at the interval of 45 days.

Results

The melting point of T₁, T₂, T₃ and T₄ developed in current investigation were 34.2, 33.8, 33.1 and 32.5 °C, respectively. The solid fat index of control, T₁, T₂, T₃ and T₄ were 47.21, 22.71, 20.33, 18.12 and 16.58%, respectively. The α-linolenic acid contents in T₁, T₂, T₃ and T₄ were found 2.92, 5.85, 9.22, 12.29%, respectively. The concentration of eicosanoic acid in T₂, T₃ and T₄ was 1.82, 3.52, 6.43 and 9.81%, respectively. The content of docosahexanoic acid in T₂, T₃ and T₄ was present 1.26, 2.64, 3.49 and 5.19%, respectively. The omega-3 fatty acids were not detected in the control sample. Total phenolic contents of control, T₁, T₂, T₃ and T₄ samples were 0.27, 2.22, 4.15, 7.23 and 11.42 mg GAE/mL, respectively. DPPH free radical scavenging activity for control, T₁, T₂, T₃ and T₄ was noted 65.8, 5.37, 17.82, 24.95, 45.42 and 62.8%, respectively. Chlorogenic acid, caffeic acid, quercetin, phenolic glycoside k and phenolic glycoside Q in T₃ were present 0.78, 0.73, 1.82, 4.12 and 4.49 mg/mL, respectively. After 90 days of storage period, free fatty acids and peroxide value of all the treatments were less than 0.2 (% and MeqO₂/kg). Sensory characteristics of treatments were not different from the control.

Conclusion

Margarines supplemented with chia oil showed enhanced level of omega-3 fatty acids and antioxidant characteristics. These results suggest that chia oil can be used for formulation of margarine with increased level of omega-3 fatty acids and acceptable sensory characteristics.

Promising features of mango (Mangifera indica L.) kernel oil: a review

Mango kernel contains about 15 % good quality edible oil, that is comparable to soybean and cottonseed, which contain about 18-20 % oil. Mango kernel oil (MKO) has lower free fatty acids, carotenoid content and peroxide value, and is usually used without any processing, which is otherwise mandatory for commercial vegetable oils. Palmitic, stearic and oleic acids are the major fatty acids, triglyceride composition and fatty acid profile suggest wide range of trans free options. With 32-36 °C melting point, MKO is solid at room temperature, thus, does not require partial hydrogenation for application in foods. MKO can be used as an alternative of cocoa butter, which is used in chocolates and confectionaries. Total phenolic contents and induction period of MKO is greater than many commercial vegetable oils; thus, it can be used as an alternative of synthetic antioxidants for the preservation of fats and oils. Mangiferin, chlorogenic acid, quercetin and caffeic acid are the major phenolic compounds present in MKO. Functional properties of MKO can be further improved through fractionation, transesterification and interesterification for increased industrial applications.

Relative bioavailability of folate from the traditional food plant Moringa oleifera L. as evaluated in a rat model

Moringa oleifera is an affordable and rich source of dietary folate. Quantification of folate by HPLC showed that 5-formyl-5,6,7,8-tetrahydrofolic acid (502.1 μg/100 g DW) and 5,6,7,8-tetrahydrofolic acid (223.9 μg/100 g DW) as the most dominant forms of folate in M. oleifera leaves. The bioavailability of folate and the effects of folate depletion and repletion on biochemical and molecular markers of folate status were investigated in Wistar rats. Folate deficiency was induced by keeping the animals on a folate deficient diet with 1 % succinyl sulfathiazole (w/w). After the depletion period, animals were repleted with different levels of folic acid and M. oleifera leaves as a source of folate. Feeding the animals on a folate deficient diet for 7 weeks caused a significant (3.4-fold) decrease in serum folate content, compared to non-depleted control animals. Relative bioavailability of folate from dehydrated leaves of M. oleifera was 81.9 %. During folate depletion and repletion, no significant changes in liver glycine N-methyl transferase and 5-methyltetrahydrofolate-homocysteine methyltransferase expression were recorded. In RDA calculations, only 50 % of natural folate is assumed to be bioavailable. Therefore, the bioavailability of folate from Moringa is much higher, suggesting that M. oleifera based food can be used as a significant source of folate.