Detente Instantanee Controlee Research Articles

Enhancement of Bioactive Compounds and Antioxidant Activities of Olive (Olea europaea L.) Leaf Extract by Instant Controlled Pressure Drop

In this work, the effect of Detente Instantanee Controlee (DIC) (French for instant controlled pressure drop) on the total polyphenol, flavonoids, α-tocopherol contents, and antioxidant activities of olive leaves was studied. Olive leaf extracts were pre-treated at one cycle DIC under 0.1 MPa pressure for 11 s and followed by an extraction with 95% ethanol at 55 °C during 3 h. The phenolic compounds, flavonoids, oleuropein, and α-tocopherol contents were determined, showing 66.63 mg gallic acid equivalent (GAE)/g db, 12 mg catechin equivalent (CE)/g db, 43.9 mg/g db, and 0.15 mg/g db for the untreated leaves against 239.37 mg GAE/g db, 28 mg CE/g db, 70.3 mg/g db, and 0.59 mg/g db for DIC-treated leaves, respectively. Therefore, DIC allows more availability of bioactive compounds contributing to a high antiradical activity (DPPH) compared to a synthetic antioxidant butylated hydroxytoluene (BHT). Both extracts showed a total antioxidant capacity (method of phosphomolybdenum) greater than that of the standard BHT. Likewise, both extracts have a reducing power (FRAP test) significant concentration-dependent. The DIC-treated leaves showed a higher antioxidant capacity compared to that of untreated leaves. Thus, DIC could be an effective treatment to promote the extraction of bioactive molecules of high antioxidant activities from olive leaves.

Strategy of experimental design for intensification of solvent extraction of natural antioxidant flavonoids and phenols from buckthorn textured leaves

AbstractPrior to solvent extraction of plant-based active molecules, adequate texturing by Detente Instantanee Controlee (DIC; French for “Instant controlled pressure drop”) results in overcoming the slow diffusion of the solvent/solute through the solid matrix. This work aimed at determining the impact of DIC pretreatments on buckthorn (Rhamnus alaternus L.) morphology. DIC-operating parameters were selected as the saturated steam pressure, the thermal treatment time, and the number of cycles. A three-parameter five-level response surface method was used to optimize DIC processing parameters. Response factors were the overall and individual yields of flavonol aglycone extraction, and antioxidant activity of both expanded dried material (swell dried leaves) and extracts. The yield of flavonol aglycones was 18.23 mg Kaemp eq/g dry basis (mg Kaemp eq/g db) in 3 min for DIC-treated buckthorn, against 12.24 mg Kaemp eq/g db in 150 min for untreated natural buckthorn raw material. Furthermore, the antioxidant ...

Instant Controlled Pressure Drop Combined to Ultrasounds as Innovative Extraction Process Combination: Fundamental Aspects

Abstract To entirely recover and value orange peels by extracting both essential oils and antioxidant compounds, hydrodistillation and standard solvent extraction are usually used. These treatments are known as long, fastidious,and energy-consuming processes mainly because of a low diffusivity coupled with a low starting accessibility. Various innovative processes were recently proposed, studied and optimized. They could have their own advantages. By analyzing the fundamental aspects of different processes, it was possible to recognize the limiting phenomena.Therefor, combining adequate innovative processes intensified the whole operation.This will increase heat and mass transfers; both process performance and extract quality could be dramatically improved.DIC (Detente InstantaneeControlee), instant controlled pressure-drop treatment enhances autovaporization, which results in an expansion of the sample. The autovaporization enables a direct extraction of essential oils simultaneously triggering expansion, which enhances the availability of some molecules and also increases solvent diffusivity within the plant matrix. Ultrasound extraction process is fast in comparison with standard methods, thanks to a greater contact surface area between solid and liquid phase. It was possible to compare the effect of ultrasound-assisted extraction to standard solvent extraction in terms of fundamental aspects, highlighted with a former experimental study. Fundamentals enabled the study and comprehension of the extraction modelling.As an example, orange peel extraction has been studied. In order to achieve innovative extraction, we combined and associated these two techniques. We carry outthe treatment by DIC to extract the essential oils and at the same time to obtain a textured vegetal material. Followed by ultrasound assisted solvent extraction, a great intensification of antioxidants extraction is generated. It was possible to compare the effect of ultrasound assisted extraction to standard solvent extraction both achieved on dried orange peels as raw material and DIC treated material. Combining DIC to ultrasounds enabled enhancing yields and extraction kinetics of antioxidant.

Characterization of pure cheese snacks and expanded granule powders textured by the instant controlled pressure drop (DIC) process

In this study, a new concept of pure cheese crispy snacks has been defined. The process used is the Detente Instantanee Controlee (DIC), for instant controlled pressure drop treatment, inserted between two air drying stages. Such cheese snacks can reach low water content (W<3 g H2O/100 g dry basis) and achieve high crispness level. A final simple grinding allows expanded granule cheese powders to be obtained. This paper investigates the impact of this process in terms of physical and structural properties such as specific density, expansion ratio, compressibility, etc. Cheese pieces can be expanded to a volume ca. 3,500% of original size, with a sharp decrease in the specific density of pieces from an initial value of 1,118±5 kg.m �3 , for untreated samples, which is close to the intrinsic density value, toward 33±5 kg.m �3 for the most expanded samples. The values of specific density strictly depend on the DIC processing parameters; the higher the DIC steam pressure, the higher the expansion ratio, and the higher the porosity (results not shown), the lower the specific density of the cheese snacks. The final powder granules can have small size (around 250 μm), an expanded structure, and thus a low bulk density and a high specific surface area. The results revealed the high capability of the DIC process to produce expanded perfectly dried cheese snacks and powders.

Study of a new extraction process: controlled instantaneous decompression. Application to the extraction of essential oil from rosemary leaves

Experiments to extract the essential oil from rosemary (Rosmarinus officinalis L.) were carried out using a new process: 'Detente Instantanee Controlee (DIC) or controlled instantaneous decompression. This process involves subjecting the rosemary leaves for a short period of time to a steam pressure varying from 0.5 to 3 bar, followed by an instantaneous decompression to a vacuum (about 15 mbar). We have studied the effect of pressure, processing time and the number of decompressions on the extraction efficiency. The moisture content of the rosemary leaves before treatment was maintained at about 35%. Qualitative and quantitative chemical analyses were undertaken on the essential oil present in the rosemary leaves after extraction by steam distillation, and on the liquid extract. It appears that a pressure of the order of 1 bar and a treatment time of 10 minutes are sufficient to extract more than 90% of the essential oil. The effect of modifying the operating parameters on the efficiency of extraction of 10 components of the rosemary essential oil was also studied. Our results show that in the solid phase over 97% of essential oil compounds were extracted from the plant leaves after a 10 minute treatment at 3 bar. Furthermore, the efficiency of the extraction of rosemary essential oil was confirmed by scanning electron microscopy. © 1998 John Wiley & Sons, Ltd.