Extraction, chemical composition and nutrional characterization of vegetable oils: Case of Amaranthus hybridus (var 1 and 2) of Congo Brazzaville

Amaranthus hybridus is a vegetable which is eaten in Congo Brazzaville and in other countries. Two varieties of A. hybridus seeds (var 1 and 2) were selected for this study. Average oil content varies between 11 and 14%. A. hybridus seeds are also rich in proteins (17%) and minerals. Red oils obtained have a high saponification value (130-190) and the iodine value is between 100 and 113. The quantity of unsaponifiable matter (5 - 7%) in these oils is important. The fatty acids composition gives the following average profile: 18: 2n-6 > 18: 1 n-9 > 16: 0 > 22: 6n-3 > 18: 0. A. hybridus seeds oils also have long chain poly unsaturated fatty acids such as DHA (5.63-21.46%) and the results indicated that the n-6/n-3ratios were 1.48 to 5.63. The triacylglycerols analysis shows that oils extracted by Bligh and Dyer method contains 6 major TAGs in A. hybridus var1: LLnLn › OLL › POL. › OLL › PLL › LLL and Amaranthus hybridus var2: LLnLn › OLL › PLL › POL. › OLL › LLL. The A. hybridus seeds can be used ascattle food and baby complement food. These oils have nutritive and dietetic potentialitie

Extraction and nutritional properties of Solanum nigrum L seed oil

With the aim of diversifying the lipids sources eaten by the African populations and those of Congo Brazzaville in particular, a physicochemical study of Solanum nigrum L seeds was carried out and three chemical methods (Soxhlet, Bligh and Dyer, and Folch) were used to extract the oil. The dry matter content of the seeds is 94.22%. Average lipids content varies between 34.5 and 37.5% dry matter, proteins content is 17% dry matter and crude ash content averages 7.18% dry matter and the principal mineral element is Mg (180 mg/100g). The acid value of the oil is about 2.5, saponification value varies between 157.3 and 190.1, peroxide value is low at 5.13 and iodine is 102.33.The fatty acid compositions of S. nigrum seeds oil shows that it has 67.9% of linoleic acid, indicating its high unsaturation. Apart from linoleic acid, other prominent fatty acids were palmitic, stearic and oleic acids. The following average profile is: 18: 2n-6 > 18: 1 n-9 > 16: 0 > 18: 0. The oil is liquid at room temperature and green in colour. Oil viscosity varies between 20 and 35 mPa.s at 25°C. Three activation energies which vary between 0.8 to 26.58 kJ.mol-1 were determined using Arrhenius’s equation. The melting points estimated by Differential Scanning Calorimetry were found to be between -22.0 and -12.0°C for the Soxhlet and Folch-extracted oils. Bligh and Dyer oil have three melting points at -36.2, -15.2 and 33.7°

A study on gumbo seed grown in Congo Brazzaville for its food and industrial applications

Proximate composition, energy content and mineral concentrations of okra seeds grown in two localities of Congo Brazzaville were investigated. The paper also reports the physicochemical characteristics of the oil extracted from the seeds. Ash was highest (5.84±0. 2%) in Dolisie okra seeds (DOS) followed by Brazzaville okra seeds (BOS) with a value of 5.52±0.34%. Protein ranged from 25.48±0.57% in DOS to 23.73±0.35% in BOS. Crude fat content is of 29.31±0.83% for BOS and 25.71±0.44 % for DOS. Totalcarbohydrates were generally high in all the seeds and ranged from 31.84% in BOS to 231.27% in DOS. The seeds were found to be good sources of minerals. Phosphorus (1755.95–1464.87 mg/100 g), magnesium (3895.67–2743.5 mg/100 g) and potassium (124.59-116.05 mg/100 g), were highest in two okra seeds cultivars. The physical properties of the oil extracts showed the state to be liquid at room temperature and the colour to be golden-yellow, in general. Thermal analysis show that fatty acids melting point was lowest ranged between -25°C and +6.55°C. Gas liquid chromatography revealed thatthe major fatty acid was linoleic acid (34.89-44%), palmitic acid (25.2-28.3%) and oleic acid (21.9-24.08%). Abelomschus esculentus seeds oil (AESO) content long chain poly unsaturated acids aseicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) and erucic acid (1.1–4.1%). It can be inferred that the oil seeds investigated are good sources of crude fat, crude protein, ash and minerals. The oil extracts exhibited good physicochemical properties and could be useful as edible oils and for industrial applications

Tracking System with Re-identification Using a RGB String Kernel

International audiencePeople re-identification consists to identify a person which comes back in a scene where it has been previously detected. This key problem in visual surveillance applications may concern single or multi camera systems. Features encoding each person should be rich enough to provide an efficient re-identification while being sufficiently robust to remain significant through the different phenomena which may alter the appearance of a person in a video. We propose in this paper a method which encodes people's appearance through a string of salient points. The similarity between two such strings is encoded by a kernel. This last kernel is combined with a tracking algorithm in order to associate a set of strings to each person and to measure similarities between persons entering into the scene and persons who left it

Effect of Pulsed or Continuous Delivery of Salt on Sensory Perception Over Short Time Intervals

Salt in the human diet is a major risk factor for hypertension and many countries have set targets to reduce salt consumption. Technological solutions are being sought to lower the salt content of processed foods without altering their taste. In this study, the approach was to deliver salt solutions in pulses of different concentrations to determine whether a pulsed delivery profile affected sensory perception of salt. Nine different salt profiles were delivered by a Dynataste device and a trained panel assessed their saltiness using time–intensity and single-score sensory techniques. The profile duration (15 s) was designed to match eating conditions and the effects of intensity and duration of the pulses on sensory perception were investigated. Sensory results from the profiles delivered in either water or in a bouillon base were not statistically different. Maximum perceived salt intensities and the area under the time– intensity curves correlated well with the overall perceived saltiness intensity despite the stimulus being delivered as several pulses. The overall saltiness scores for profiles delivering the same overall amount of sodium were statistically not different from one another suggesting that, in this system, pulsed delivery did not enhance salt perception but the overall amount of salt delivered in each profile did affect sensory perception

Characteristic Physicochemical of Oil Extract from Moringa oleifera and the Kinetics of Degradation of the Oil during Heating

Abstract: The aim of the study was to investigate the physicochemical properties and the kinetics of degradation of Moringa oleifera seed oil during heating. The seed is a good source of oil (40%). The physical properties of the oil extracts showed the state to be liquid at room temperature and indicated that the oil had refractive index, 1.4680; the peroxide value, 1.67 (meq O 2 /kg oil); free fatty acid, 2.10%; iodine value, 66.2%; saponification value, 167; unsaponifiable matter content, 0.87% and viscosity, 47.24 (mPa.s at 25°C). Gas liquid chromatography technique has been developed for identification and quantitative determination of total unsaturated and saturated fatty acids shows that the crude oil had 79.57 and 20.42% respectively. Differential Scanning Calorimetry (DSC) indicates the presence of three components in oil extracted. The first peak at low melting point appears at -31.10°C (∆H f = -5.36 J/g), the second peak appears to -7.03°C (∆H f = +49.56 J/g) and the last peak appears to +6.30°C (∆H f = +0.55 J/g). The degradation kinetic of the oil was also investigated. The thermal oxidation of the double bonds of the oil showed a first-order thermal oxidation kinetic and the Arrhenius plot yielded a straight line with a slope equivalent to activation energy of 1.593 KJ/mol. There is the possibility of considering the seed as feed supplement and its oil for industrial application

Optimization of spray-drying conditions for lulo (Solanum quitoense L.) pulp

The spray drying of lulo was optimized by using the central composite design of the response surface methodology, to study the effect of inlet air temperature (120-180 degrees C), arabic gum concentration (0-10% w/w), and maltodextrin DE16.5-19.5 concentration (0-10% w/w) on some product and process aspects. Arabic gum and maltodextrin, more than inlet air temperature, improved the product yield, reduced the hygroscopicity and the water content of the obtained powder, and contributed to the retention of its nutritive and functional properties through an increase in ascorbic acid, vitamin C, total phenol and total flavonoid content and antioxidant capacity. Significant (p < 0.05) response surface models were obtained in every case, with the linear terms of solute concentration being the factors that affected the response variables most significantly. The overall optimum spray drying conditions for obtaining lulo powder were 125 degrees C inlet air temperature, 3% (w/w) arabic gum, and 13.4% (w/w) maltodextrin DE16.5-19.5. (C) 2014 Elsevier B.V. All rights reserved.The authors thank the Universidad Politecnica de Valencia for the financial support given throughout the Project ADSIDEO-COOPERACION 2010 "Adaptacion de procesos de secado para favorecer la comercializacion de super frutas de origen colombiano".Igual Ramo, M.; Ramires, S.; Mosquera, LH.; Martínez Navarrete, N. (2014). Optimization of spray-drying conditions for lulo (Solanum quitoense L.) pulp. Powder Technology. 256:233-238. doi:10.1016/j.powtec.2014.02.003S23323825

Online change detection in exponential families with unknown parameters

International audienceThis paper studies online change detection in exponential families when both the parameters before and after change are unknown. We follow a standard statistical approach to sequential change detection with generalized likelihood ratio test statistics. We interpret these statistics within the framework of information geometry, hence providing a unified view of change detection for many common statistical models and corresponding distance functions. Using results from convex duality, we also derive an efficient scheme to compute the exact statistics sequentially, which allows their use in online settings where they are usually approximated for the sake of tractability. This is applied to real-world datasets of various natures, including onset detection in audio signals