Nyam K.L.,UCSI University |
Teh Y.N.,UCSI University |
Tan C.P.,University Putra Malaysia |
Kamariah L.,Development Institute MARDI
Malaysian Journal of Nutrition | Year: 2012
Introduction: In order to overcome the stability problems of oils and fats, synthetic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert-butyl hydroquinone (TBHQ) have widespread use as food additives in many countries. Recent reports reveal that these compounds may be implicated in many health risks, including cancer and carcinogenesis. Hence, there is a move towards the use of natural antioxidants of plant origin to replace these synthetic antioxidants. Methods: In this study, roselle seed oil (RSO) and extract (RSE) were mixed with sunflower oil, respectively to monitor degradation rate and investigate antioxidant activity during accelerated storage. Results: The antioxidant activity was found to stabilise sunflower oil of various samples and in the order of RSE>RSO>tocopherol>sunflower oil. The total percentage increased after 5 days of storage period in free fatty acid (FFA), peroxide value (PV) and anisidine value (AV). Total oxidation value (TOx) of sunflower oil supplemented with 1500 ppm RSE was 33.3%, 47.7%, 14.5%, and 45.5%, respectively. While the total percentage increased under different analysis methods, sunflower oil supplemented with 5% RSO was 17.2%, 60.4%, 36.2% and 59.0% in the order of FFA, PV, AV and TOTOX. Both RSO and RSE were found to be more effective in stabilisation of sunflower oil compared to tocopherol. Total phenolic content of RSE was 46.40 ± 1.51 mg GAE/100g of oil while RSO was 12.51 ± 0.15 mg GAE/100g of oil. Conclusion: The data indicates that roselle seed oil and seed extract are rich in phenolics and antioxidant activities and may be a potential source of natural antioxidants.
Abdullah H.,Development Institute MARDI |
Razali M.,Development Institute MARDI |
Rohaya M.A.,Development Institute MARDI
Acta Horticulturae | Year: 2012
Postharvest handling system is a vital and dynamic component of the horticultural industry in tropical Malaysia. Earlier development of postharvest handling technology in Malaysia in the late 1970s to 1980s was targeted mainly at reducing postharvest losses as that was the major issue at that time. However, recent postharvest activities have been focused on quality improvement of produce for both domestic and export markets. It is important to develop technologies which can fulfil the needs of the industry. Many achievements have been made with regard to postharvest handling of horticultural produce. Recent advances include further extension of storage life, suitable physical and chemical treatments for quality maintenance, minimal processing and shipment trials to new markets. Improvements on specific postharvest traits have also been made through manipulation of agronomic practices and breeding programme. The climax of the activities is the successful handling and transportation trials of Malaysian horticultural produce conducted to various global destinations by sea shipment. The postharvest activities have also strengthened linkages between the R&D institutions with relevant government agencies and private sector both locally and internationally.