Kenaf seed oil contains high amount of monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA), and bioactive compounds, such as tocopherol and phytosterol. In order to prevent bioactive compounds from oxidation, kenaf seed oil (KSO) was encapsulated by coextrusion technology. KSO and microencapsulated kenaf seed oil (MKSO) were then subjected to accelerated storage to investigate the effect of microencapsulation on the storage stability of kenaf seed oil. The changes of fatty acids profiles and bioactive compounds in oils were evaluated. Result showed that there was significant decreased (p
Introduction: The aims of this study were to determine the proximate composition, functional properties and antioxidant activity of pumpkin seeds and rind. Besides, the effects of dietary fibre in pumpkin seeds and rinds on bread qualities and properties were evaluated. Methods: Formulations for bread substituted with 0%, 5% and 10% pumpkin seed and rind, respectively were produced. Sensory evaluation of the prepared bread samples for such attributes as appearance, aroma, flavour, texture and overall acceptability was undertaken. The physical properties of the bread samples, including dough expansion, loaf volume, crumb colour and bread texture, were determined. Proximate analysis and determination of antioxidant activity of the bread samples were also conducted. Results: Crude fibre of the pumpkin seeds and pumpkin rinds was high at 31.48% and 14.83%, respectively. The total phenolic compound (TPC) and DPPH radical scavenging activity for the pumpkin rinds were 38.60 mg GAE/ 100 g dry weight and 69.38%, respectively, which were higher than those of pumpkin seeds. A 5% level of pumpkin rind bread gave the best overall acceptability and sensory attributes, followed by 5% pumpkin seed bread. Total dietary fibre, total phenolic compound and DPPH radical scavenging activity in breads substituted with 5% pumpkin seed and 5% pumpkin rind flour were higher than the values in control bread. Conclusion: Pumpkin seeds and rinds can be used as dietary fibre sources in bakery.
The aim of this study was to investigate the oxidative stability, antioxidant activity and fatty acid composition of 2 minutes microwave pre-treated kenaf seed oil (MKSO) in comparison with the untreated kenaf seed oil (KSO) under accelerated storage for 24 days. Results obtained on oxidative stability for both KSO and MKSO by the end of storage with PV were 9.83 meq O2 /kg and 8.97 meq O2 /kg, respectively; p-Anv were 17.28 and 13.48, respectively; TOTOX value of 36.94 and 31.42, respectively; IV value were measured 84.50 g of I2 / 100 g and 84.34 g of I2 / 100 g oil, respectively; FFA value of 5.67 mg KOH/100g oil and 5.14 mg KOH/100g oil, respectively. Aside from that, the antioxidant activity in MKSO was better than KSO. For the fatty acid composition, the oleic and linoleic acids were affected significantly throughout storage for both KSO and MKSO. MKSO presented a better overall oxidative stability, antioxidant activity and retained higher content of MUFA and PUFA significantly (p< 0.05) upon accelerated storage.
With the concern of adverse effects of lipid oxidation on food deterioration and human health, the antioxidant activities of kenaf seed extracts (KSE), roselle seed extracts (RSE) and roselle extracts (RE) were evaluated by comparing its oxidative stability in refined, bleached & deodorised (RBD) sunflower oils with that of in synthetic antioxidant, BHA. Established methods such as peroxide values (PV), p-anisidine values (AV), TOTOX values, free fatty acids (FFA), iodine values (IV), total phenolic contents (TPC), conjugated dienes (CD) and conjugated triene (CT) were employed to assess the extent of oil deterioration. During 24 days storage, consensus was accomplished based on the results assessed by PV, TOTOX, CD, CT, IV and TPC at which the antioxidant activities of KSE, RSE and RE were better than BHA. Surprisingly, the results obtained by AV and FFA assays showed the reversed. Among the extracts, RSE exhibited the best antioxidant activities. These suggest that KSE, RSE and RE may be used as potential source of natural antioxidants in the application of food industry to prevent lipid oxidation.