Rhoda Joy Q. Baltazar, Florian D. Servidad, Nikita Tajik M. Panganiban (March 2007)
Philippine Science High School Western Visayas Campus – Department of Science and Technology (DOST-PSHS WVC), Brgy. Bito-on, Jaro, Iloilo City 5000, Philippines
ABSTRACT
Virgin coconut oil is one of the most popular products in the commercial market today mostly because of its health benefits. Its physico-chemical properties help in determining its quality, but studies conducted under this area are limited.
This study aimed to determine the physico-chemical properties affecting the quality of the virgin coconut oil extracted from coconuts of different maturity levels.
Virgin coconut oil was extracted from 11-, 12, 13, 14-, and 15-month old coconuts using the cold press method. The specific gravity, saponification number, and iodine value were determined at DPSM laboratory. Peroxide value, boiling point, freezing point, melting point, percent oil yield, and molecular weight were determined at PSHSWV laboratory.
Results from one-way ANOVA (a=0.05) showed that there is a significant difference in the specific gravity, boiling point, peroxide value, saponification number, iodine value, and percent oil yield of the oil produced from the five maturity levels. However, there was no significant difference in the melting and freezing points, and the molecular weight.
Good quality virgin coconut oil is characterized by high specific gravity, high melting and freezing point, low boiling point, high peroxide value, low saponification number, low iodine value, high percent oil yield, and high molecular weight. Based on the Multiple comparison using Fisher’s Least Significant Difference Post-Hoc Test (a=0.05), among the parameters where a significant difference exists, virgin coconut oil from 11 and 13 months old coconuts possess these desirable qualities for specific gravity, boiling point, peroxide value, saponification number, and iodine value.