Idris Nor Aini

Antioxidative properties of Murraya koenigii leaf extracts in accelerated oxidation and deep-frying studies

Murraya koenigii leaf extract antioxidant potentials were evaluated in palm olein using accelerated oxidation storage and deep-frying studies at 180°C for up to 40 h. The extracts (0.2%) retarded oil oxidation and deterioration significantly (P<0.05), slightly less effectively than 0.02% butylated hydroxytoluene in tests such as the peroxide value, anisidine value, iodine value, free fatty acid, Oxidative Stability Index, and polar and polymer compound content. Sensory evaluation on French fries indicated that the extract was useful in improving colour, flavour and overall acceptability and the quality of the fried product. All samples were more acceptable by panellists, especially after the 40th hour frying, compared with those similarly fried in the control oils and the oil containing butylated hydroxytoluene. M. koenigii leaf extract, had a polyphenol content of 109.5±0.3 mg gallic acid equivalents/g extract, and contain a heat-stable antioxidant that could be a natural alternative to synthetic antioxidants for the industry.

Relationship between textural properties and sensory qualities of cookies made from medium- and long-chain triacylglycerol-enriched margarines.

BACKGROUND This study aims to investigate the textural properties and sensory qualities of cookies made from medium- and long-chain triacylglycerol (MLCT)-enriched margarines. Margarine with formulations of MLCT:palm olein:palm stearin, 60:30:10 and 70:20:10, were selected to produce cookies. The textural properties of cookies were determined using a texture analyser. Quantitative descriptive analysis (QDA) and acceptance test were carried out to describe the attributes and to evaluate the degree of liking of cookies, respectively. RESULTS Cookies made from MLCT-enriched margarines showed high values for hardness, fracturability, but also for cohesiveness and adhesiveness. Trained panelists rated the cookies made from MLCT-enriched margarines to be lower as compared to those made from commercial margarine for most of QDA attributes. However, cookies made from MOS 603010 and commercial margarines were scored similarly (P > 0.05) for all acceptance test attributes. Overall acceptability was found to be highly and negatively correlated for hardness, fracturability and cohesiveness (R(2) > 0.90). Principal component analysis showed that the taste attribute of cookies and the % solid fat content of margarine at 35 degrees C highly influenced the overall quality of the cookies. CONCLUSION Cookies made from MLCT-enriched margarines were not successfully produced. However, the findings obtained provide new perspectives in the production of low-calorie bakery fat.