Zaibunnisa Abdul Haiyee

Combination of Sensory, Chromatographic, and Chemometrics Analysis of Volatile Organic Compounds for the Discrimination of Authentic and Unauthentic Harumanis Mangoes

This study analyzed the volatile organic compounds (VOCs) of three mango varieties (Harumanis, Tong Dam and Susu) for the discrimination of authentic Harumanis from other mangoes. The VOCs of these mangoes were extracted and analysed nondestructively using Head Space-Solid Phase Micro Extraction (HS-SPME) coupled to Gas Chromatography-Mass Spectrometry (GC-MS). Prior to the analytical method, two simple sensory analyses were carried out to assess the ability of the consumers to differentiate between the Harumanis and Tong Dam mangoes as well as their preferences towards these mangoes. On the other hand, chemometrics techniques, such as principal components analysis (PCA), hierarchical clustering analysis (HCA), and discriminant analysis (DA), were used to visualise grouping tendencies of the volatile compounds detected. These techniques were successful in identifying the grouping tendencies of the mango samples according to the presence of their respective volatile compounds, thus enabling the identification of the groups of substances responsible for the discrimination between the authentic and unauthentic Harumanis mangoes. In addition, three ocimene compounds, namely beta-ocimene, trans beta-ocimene, and allo-ocimene, can be considered as chemical markers of the Harumanis mango, as these compounds exist in all Harumanis mango, regardless the different sources of the mangoes obtained.

Komposisi nutrisi dan analisis warna serbuk kuning telur rendah-kolesterol

Dietary cholesterol should be limited to less than 200 mg/day. A single large egg yolk contains approximately 275 mg of cholesterol. Thus, consumption of a single egg yolk exceeds the recommended daily intake of cholesterol. This study was focused on determination of the effect of addition of increasing amount of β-cyclodextrin (β-CD) to encapsulate cholesterol in egg yolk. The quality of cholesterol-reduced egg yolk powder was evaluated by determining its nutritional composition and colour analysis. Increasing amount of β-CD (0 – 15 mM) was added in liquid egg yolk and the encapsulated cholesterol in the form of precipitate was removed. The supernatant was dried and the end product; cholesterol-reduced egg yolk powder (CREYP) was analyzed for moisture content, total lipid, fatty acids content, protein and colour. There were no significant difference (p > 0.05) in term of total solid content. However, protein content of CREYP was significantly (p < 0.05) reduced up to 7 mM β-CD and no further significant reduction was noticed with further addition of β-cyclodextrin. The appearance of the powder became lighter in colour as validated using chromameter; L*, a*, b*, C* and h values. The results obtained from this study indicate that cholesterol can be successfully removed from egg yolk. However, slight reduction in protein content was observed. Nutritional composition of CREYP was minimally affected with the removal of encapsulated cholesterol. Therefore, cholesterolreduced egg yolk powder can be utilized as an essential ingredient in any egg yolk based products.

Subcritical Water Extraction (SWE) of Anthocyanin from Arabica Coffee Pulp

Coffee pulp which is 45-55% of coffee cherry is the main by-product from coffee processing industry. Analysis of cyanidin-3rutinoside (C-3-R), the major anthocyanin in coffee pulp is important for the development of value-added products. The SWE parameters including extraction temperature, extraction time and cycle were studied for selective and efficient extraction of C3-R from Arabica coffee pulp. Quantitative analysis was obtained using high performance liquid chromatography (HPLC). SWE is a promising green approach in the extraction of bioactive compounds from plants materials.