Characterization of the Pulp and Kernel Oils from Syagrus oleracea, Syagrus romanzoffiana, and Acrocomia aculeata

Abstract

Vegetable oils are important sources of essential fatty acids. It is, therefore, important to characterize plant species that can be used as new oil sources. This study aimed to characterize the oils from guariroba (Syagrus oleracea), jerivá (Syagrus romanzoffiana), and macaúba (Acrocomia aculeata). The physicochemical characterization was performed using official analytical methods for oils and fats, free fatty acids, peroxide value, refractive index, iodine value, saponification number, and unsaponifiable matter. The oxidative stability was determined using the Rancimat at 110 °C. The fatty acid composition was performed by gas chromatography. The results were submitted to Tukey's test for the medium to 5% using the ESTAT program. The pulp oils were more unsaturated than kernel oils, as evidenced by the higher refractive index and iodine value, especially the macaúba pulp oil which gave 1.4556 and 80 g I(2) /100 g, respectively, for these indices. The kernel oils were less altered by oxidative process and had high induction period, free fatty acids below 0.5%, and peroxide value around 0.19 meq/kg. The guariroba kernel oil showed the largest induction period, 91.82 h. Practical Application: The vegetable oils, besides being consumed directly as food, are important raw material for the chemical, pharmaceutical, and food industries. In recent years, the world market of vegetable oils has been characterized by stronger growth of demand over supply. Several species of palm trees are shown to be promising sources of oils. The characterization of oils extracted from some species, such as guariroba, jerivá, and macaúba, has not yet been fully elucidated. For this reason, it becomes important to investigate the physicochemical characterization of these oils, aiming at a possible use in food or in the industry.