Steam Distillation of Essential Oil from Lemongrass (Cymbopogon citratus) using Microwave Pretreatment

Essential oils from lemongrass (Cymbopogon citratus) containing citral are very potential to be used in food and pharmacy industries. The process of isolating essential oils is still constrained by its low yield. In order to increase yield, in this research, isolation of essential oil by steam distillation method was carried out using microwave pretreatment. The results showed that pretreatment using microwave for 2 minutes had the effect of increasing yield up to 1.4 times compared to without pretreatment. The essential oil produced using microwave pretreatment had physical properties (colour, odor, density, and refractive index) similar to those without pretreatment. Composition analysis by GC-MS showed that essential oils extracted using microwave pretreatment and without pretreatment contain geranial (Ecitral or citral-a), neral (Z-citral or citral-b) and mircena as the main components

Optimization of microwave assisted mechanical extraction of oil from canola seeds by using Response Surface Methodology

Present investigation was undertaken with the overall objective of optimizing the microwave assisted pressing parameters, i.e. microwave time, moisture content, heating temperature and heating time for increasing the oil recovery from canola seeds of GSC-6 variety.  Response surface methodology was adopted in the experimental design and Box Bhenken design of four variables was chosen.  The range of parameters for the experiments was microwave time (2-4 min), moisture content (5%-15%), heating temperature (60-1000℃) and heating time (4-6 min) and single chamber oil expeller was used for oil expelling.  The effect of independent variables, i.e. moisture content, microwave duration and heating temperature on oil yield and residual oil in cake were found significant, however, the effect of the heating time was found non-significant.  Microwave time, moisture content and heating temperature affected the acid value and the peroxide value of the oil.  Heating temperature affected the viscosity of the oil.

Influencia del tostado por microondas en los componentes bioactivos y los parámetros químicos del aceite de semilla de higo prensado en frío

The effect of microwave roasting process on the compositional parameters and bioactive contents of fig seed oil were investigated. Fig seeds were ground and roasted in a microwave oven at 350, 460 and 600 Watt for 5 and 10 minutes and the roasted seeds were processed to obtain oil. The results showed that peroxide, K232 and K270 values were adversely affected by roasting. Fig seed oil was a prosperous source of γ-tocopherol and significant losses were observed due to microwave pre-treatment. The major fatty acids in fig seed oil were linolenic, linoleic and oleic acids; whereas the major triacylglycerols were LnLO, LnLnL, LnLnLn and LnLnO, according to fatty acid profile. The most abundant sterol in the fig seed oil samples was β-sitosterol with 3235.90 to 3625.62 mg/kg, followed by Δ5- and Δ7-avenasterols. The principal component analysis and agglomerative hierarchial clustering served to differentiate between intense and mild microwave-treated oils as well as the unroasted samples.Se investigó el efecto del proceso de tostado por microondas sobre los parámetros de composición y contenido bioactivo del aceite de semilla de higo. Las semillas de higo se molieron y tostaron en un horno de microondas a 350, 460 y 600 vatios durante 5 y 10 minutos a continuación se obtuvo el aceite. Los resultados han demostrado que los valores de peróxido, K232 y K270 se vieron afectados negativamente por el tostado. El aceite de semilla de higo es una buena fuente de γ-tocoferol y se observaron pérdidas significativas mediante el pretratamiento con microondas. Los principales ácidos grasos del aceite de semilla de higo fueron los ácidos linolénico, linoleico y oleico; mientras que los principales triacilgliceroles fueron LnLO, LnLnL, LnLnLn y LnLnO que ratificaron el perfil de ácidos grasos. El esterol más abundante de las muestras de aceite de semilla de higo fue el β-sitosterol que varió de 3235,90 a 3625,62 mg/kg, acompañado de Δ5-avenasterol y Δ7-avenasterol. El análisis de componentes principales y la agrupación jerárquica aglomerativa permitieron la diferenciación de aceites tratados con microondas intensos y suaves, así como las muestras sin tostar

IDENTIFIKASI KUALITAS WARNA BUAH NAGA (Hylocerecus) DENGAN EKSTRAKSI MENGGUNAKAN MICROWAVE-ASSISTED EXTRACT (MAE)

Buah naga merupakan jenis buah yang kaya dengan zat warna.  Warna ini dapat digunakan sebagai pewarna alami dalam mengatasi penggunaan pewarna buatan di masyarakat yang diluar ambang batas sehingga menimbulkan resiko bagi kesehatan.  Selain itu warna yang dihasilkan juga  mengandung senyawa polifenol yang merupakan sumber antioksidan.  Penggunaan metode dengan Microwave-Assisted Extract (MAE) dengan tujuan agar kualitas warna lebih baik dan dapat mempertahankan senyawa polifenol yang terdapat dalam buah naga tersebut.  Dari hasil penelitian didapatkan kualitas warna terbaik berasal dari kulit buah naga daging merah dengan uji kualitas  sebagai berikut : polifenol 623,1 mg GAE/100 gram, aktivitas antioksidan 41,18%, antosianin 84 mg/100 gram, betasianin 0,75 mg/100 gram dan warna 21,18

Effect of Microwave Pretreatment on Gaharu Essential Oil Using Hydrodistillation Method

Gaharu wood produces an expensive essential oil due to its fragrance and chemical compounds. Normally, the black color wood is used for the extraction of oil because it contains high resin. However, the cost of this resinous wood is very expensive. Therefore, in this study, the raw material with low resin content (identified by the white color of the wood) will be used for the extraction of oil. However, hydrodistillation alone will not produce satisfactory volume. Thus, pretreatment is needed to enhance the amount of essential oil. This paper aims to investigate the effect of microwave pretreatment on gaharu essential oil extraction using the hydrodistillation method for the lower grade wood. The gaharu wood was pre-treated with microwave irradiation power of 800 kW at three different durations which were 1, 2 and 3 min. Later, extraction was performed using the hydrodistillation method for 30 h. The chemical composition of the oil was analyzed using gas chromatography-mass spectrometry (GCMS). The results show that microwave pretreatment produced higher yield (0.0379 wt.%) of gaharu essential oil compared to the extraction of the non-pretreated wood (0.0286 wt.%) in which the increase was 24.55%. The three minutes pretreatment time produced the largest amount of oil (0.0877 wt.%). The outcomes of this study indicated the increase of chemical components of gaharu essential oils such as (+)-Epi-bicyclosesquiphellandrene, gurjunene, α-farnese, estragole, guaiene, valencene, spathulenol, α-cubebene and (-)-Spathulenol in the extraction of the pre-treated wood compared to the non-pretreated one

Optimization of the oil extraction process from wild growing pomegranate (Punica granatum L.) using microwave and analysis of biological activity of the obtained oil

Cilj ove doktorske disertacije bio je ispitivanje potencijalne primene mikrotalasnog zračenja na povećanje prinosa ulja semena divljeg nara (Punica granatum L.) nakon ekstrakcije i ispitivanje biološke aktivnosti dobijenog ulja. Ispitan je uticaj operativnih parametara (snage i vremena) mikrotalasnog zračenja na prinos i sastav ulja dobijenog natkritičnom ekstrakcijom (NKE) sa ugljenik(IV)–oksidom (CO2) i ekstrakcijom heksanom u aparaturi po Soxhlet–u (SE). Seme divljeg nara je odabrano kao sirovina za ispitivanje zbog svoje vredne biološke aktivnosti (jakog antioksidativnog i potencijalnog citotoksičnog dejstva)...The aim of this PhD thesis was investigation of the potential application of microwave radiation, in order to increase the yield of wild growing pomegranate seed oil (Punica granatum L.) after exctraction and analysis of biological activity of the obtained oil. The influence of operating parameters (power and time) of microwave irradiation on yield and composition of the oil obtained by supercritical fluid extraction with carbon dioxide (SFE) and extraction with hexane in the Soxhlet apparatus (SE) was examined. Wild growing pomegranate seed was used as raw material for experiments, due to its valuable biological activity (strong antioxidant and potential cytotoxic effect)..

Improvement of seeds oil extraction and refining with microwaves and ultrasonic technologies

This thesis investigates the feasibility of using two novel processing technologies, microwaves (MW) and ultrasound, to enhance the process efficiency, product yield and quality during the extraction of canola oil at both lab and pilot scales. MW is an alternative to conventional steaming on the preconditioning of canola seeds and cooking of flakes before the oil extraction by mechanical pressing. High frequency ultrasound, called megasonics, was assessed to enhance the recovery of residual oil from canola cake during the solvent extraction stage as an alternative to organic solvent. Furthermore, this work investigated the effect of combining chemical degumming with megasonic treatment to increase the removal of phospholipids (gums), to maximise the oil recovered, gum yield, and reduce the oil trapped into gum during the refining of canola oil. Flaked seeds were “cooked” (heat-treated) with steam or using lab scale or pilot scale microwave treatments in the temperature range of 62 °C to 130 °C before expeller pressing. Microwave cooking at 100 °C resulted in the highest increase in the pressed oil yield, which is an increase of 3.7% (w/w) on a pressed oil basis or 9.0 % (oil in seed basis) compared with steam cooking. The use of a continuous microwave process for combined conditioning of whole seeds at 50 °C and subsequent cooking of flaked seeds at 100 °C gave a 4.3 % increase in expeller oil yield, compared with steam conditioning and cooking at the same temperature. The present work explores the application of ultrasound in the megasonic range for the aqueous-based extraction of oil from canola cake instead of using organic hexane solvent. The highest NUE obtained was 49.5 % (g oil/100 g hexane extractable oil in meal) at treatment conditions of 2 MHz, 30 min, meal: water 1:9 (w/w), and 80 °C. Crude canola oil from expeller pressing contains undesirable gums mainly composed of phospholipids, which must be removed to increase the oil’s shelf life. phosphoric acid and total degumming processes showed significant phosphorus reduction in the degummed oil when applying similar megasonic conditions (2 MHz at 40 °C for 20 min). The residual phosphorus with acid megasonic-assisted degumming was below the values achieved with a total degumming process without megasonics. Such megasonic-assisted acid degumming conditions were effective in reducing residual phosphorus content in both canola and soybean oil by 54.3 % and 67.0 %, respectively, while sunflower oil (39 %, relative to the non-megasonic degumming)