Determining Frying Oil Deterioration Using Chemical and Physical Methods

This research was performed to assess the oil deterioration during deep fat frying. It was also conducted to compare and correlate oil quality parameters namely, total polar compound (TPC), free fatty acids (FFA), peroxide value (PV), P-Anisidine value (p-AV), specific extinction (E1%lcm233, 269nm), iodine value (IV), flavor, color, viscosity, with changes in the heating profile of melting point, and investigate changes in the properties of oils with different kinds of food during deep-fat frying of chicken, banana and sweet potato. The frying oil consisted of five types of commercial oils, namely, canola, corn, soybean, sunflower and palm olein. These oils were used to fry, banana, sweet potato and chicken at 185 ± 5°C for 6 hr per day for sixe days until the total time of 30 hours with an interval time of 20 min. One and half kilograms of each oil sample to be tasted and 100g of each fried product was used for the frying. The frying time was set for 7 minute for banana and sweet potato and 1 5 minute for chicken. Each day, fresh oil was added to replenish the oil used. Oils used were withdrawn on the following day and before starti ng the next frying cycle and was kept in the freezer at -20˚C. The oils were analyzed for PV, N, p-AV, FFA, E1%lcm233, 269nm, TPC, color, viscosity, flavor (by zNose) and thermal behavior (melting point by DSC). In this study, DSC was used to monitor the deterioration of frying oils during deep fat frying based on qualitative investigation of the thermal behavior (melting point). The investigation began with the successful comparison of the DSC thermal curves of five different vegetable oils. The heating thermogram for the oils showed varying degree of changes especially in the last melting peak position during the course of frying. The heating thermogram showed that there is one major peak and two small shoulders peaks and used the offset of last melting peak; ("the last order peak of the DSC heating thermogram was used to represent the changes in melting point"). Flavor analysis is typically performed by a qualitative analysis of zNose chromatogram. A novel approach using a surface acoustic wave (SAW) sensing based electronic nose for favor analysis was used in this study for detecting the losing of volatile compound in vegetables oils. A statistical correlation was carried out on the DSC heating thermogram with standard chemical and physical methods. Significant linear relationship was found between melting point, TPC, N, E1%1cm233 , 269nm and viscosity. The DSC heating thermogram showed excellent correlation (P<0.05) with the standard chemical analysis.The finding of this study reveals that palm olein showed significantly (P<0.05) lower in all measured parameters than the other oils used. The extent of oil deterioration was best reflected in the changes in percent TPC, N, E1%cm at 233n

Incidences de pluies exceptionnelles sur un aquifère libre côtier en zone semi-aride (Chaouia, Maroc)

Les eaux souterraines qui représentent les seules ressources en eau de la Chaouia côtière, sont très minéralisées : intrusion marine, évaporation et recyclage des eaux d'irrigation chargées en sels. L'évolution spatio-temporelle piézométrique et hydrochimique de cet aquifère a été observée sur 179 puits, de 1991 à 1998 qui inclue une période exceptionnellement pluvieuse. Une comparaison par rapport à l'état de la nappe en 1971, date du début de l'exploitation des eaux souterraines, a été faite. Les suivis ont montré qu'à la suite des pluies importantes de 1996 (943 mm), un rehaussement important du niveau de la nappe et des dilutions plus ou moins retardées de tous les sels en solution dans l'eau, sont mesurés dans tous les puits. En effet, la nappe qui a accusé des baisses de 10 à 20 m entre 1971 et 1995, remonte en 1996 de 4,5 à 12,5 m en moyenne surtout au centre et à l'amont de la plaine. Quant à la qualité des eaux qui s'était dégradée, elle a connu des améliorations importantes avec des variations de 0,5 à plus de 4 ms/cm au niveau de la conductivité électrique. Ces faits montrent une grande sensibilité de la nappe aux apports par les pluies qui constituent sa principale alimentation.A study of regional pollution in the coastal aquifer system between Oum-er-Rbia River and Bir Jdid (Coastal Moroccan Meseta, Morocco) was based on data gathered from 1995 to 1998. The study improved the hydrogeological and hydrochemical understanding of the aquifers. The study examined the effects of significant rains on the quantity and quality of coastal groundwater. These waters exhibited high sensitivity to the rain input.Measurements undertaken since 1991 on 179 wells in the study area reveal that the groundwaters are highly mineralized - conductivity reaches more than 10 mS/cm, depending on season and well location. These results also show high chloride concentrations (more than 3500 mg/l), sodium concentrations frequently in the 500 - 1000 mg/l range and nitrates between 150 and 250 mg/l.In coastal Chaouia, these high concentrations of dissolved mineral salts aggravate the problem of supplying quality water to the rural population for drinking or even market-gardening irrigation purposes. The area is characterized by increased irrigated surfaces (more than 16000 hectares with 4125 m3 /s) and a demographic rise that has triggered the chaotic boring of more than 2000 wells into a heterogeneous aquifer sensitive to salinity. Possible sources of this high salinity include :Seawater intrusion into coastal aquifer sectors (mainly into a two-kilometre strip of coastline). The degree and the length of the marine intrusion were exacerbated by intensive pumping for irrigation needs, particularly during the dry season. Other factors such as coastal aquifer permeability, saturation zone thickness and basement depth also affect the degree and length of the marine intrusion. Seawater pollution is more marked in the southwestern coastal area.Reuse of irrigation saline waters, especially as groundwater circulates in the coastal and eastern sectors deep in the soil (to depths of 10 m).Several important factors have been highlighted concerning the origin of the chemical elements in solution and the mechanism of hydrochemical distribution: evaporation, lithology of tapped aquifers, water table depth, distance of wells from the coast, type of soil, use of fertilizers, frequency of pumping operations, and rainfall, among others.A regular network of 179 wells was monitored and surveyed in this study. Spatial and temporal changes in the water table and in the hydrochemistry of the aquifer were monitored between 1991 and 1998, a span which included an exceptionally rainy period (1996). Data are compared with those from 1971, the year groundwater exploitation began.The studied region is characterized by a semi-arid climate, mean annual rainfall of 391 mm (between 1977 and 1998), mean temperature of 17.8 °C, and mean rainfall input of 142 mm. In the dry season, high temperature combined with low rainfall and intensive pumping operations give rise to salinization of shallow groundwater. Groundwater in the area of study circulates in two principal hydrogeological matrices :1. Sandy-calcareous Plio-Quaternary and paleozoic strata in costal sectors and the eastern part located between Tnine Chtouka and Bir Jdid. These hydrogeological strata are characterized by significant porosity and permeability and are exploited at a shallow depth, generally less than 14 m, under sandy-clayed soil.2. A Cretaceous aquifer in marly limestone located between Oum-er-Rbia River and Tnine Chtouka. This aquifer is characterized by a low permeability and a water table generally exceeding 24 m in depth.Monitoring showed that after the heavy rains of 1996 (943 mm, with infiltration of 142 mm), the water table rose markedly in all study wells and a lagged dilution (3 to 6 months) was noted for all mineral salts dissolved in water. In fact, the water table, which had dropped between 1971 and 1995 (10 m in the costal sectors and 20 m in the others parts of the studied region), rose by an average 4.5 to 12.5 m in the central and up-gradient parts of the plain. Several factors were at work between 1971 and 1995: decreased pumping times (about 15 minutes) combined with sharp decreases in the thickness of the saturated zone; appearance of a closed piezometric level in the western region between Oum-er-Rbia River and Tnine Chtouka; and desiccation of 59 wells. With the aid of a polynomial model, annual level evolution of the five coastal test piezometers showed correlation factors of 0.76 to 0.93 respectively for years 1996 and 1997. Other quantitative effects of exceptional rains on groundwater identified include: increased pumping time (up from less than 15 minutes prior to the heavy rains of 1996); increased saturated zone thickness; rises in the water-table surpassing former sea-level heights in certain wells ; general advancement of the piezometric levels towards the coastline; and increased aquifer thickness stemming from longer pumping times.In terms of quality, groundwater showed gradually increasing salinity (by a factor of 2) between 1971 and 1995 and significant improvements after the rains of 1996. Between 1971 and 1995, increased mineralization was observed mainly in coastal and eastern parts of the aquifer between Tnine Chtouka and Bir Jdid. Conductivity of the waters in some coastal wells increased from 5 mS/cm to more than 10 mS/cm. After the exceptional rains of 1996, differences ranging from 0.5 to more than 4 mS/cm were observed in 71 % of the 179 wells analysed. Over the same period, chloride concentrations decreased by average values ranging from 150 to 500 mg/l (higher decreases surpassed 1000 mg/l). By contrast, spatial distributions of conductivity and of the main mineral salts remained unchanged and coastal and eastern groundwaters were still the most vulnerable to high salinity.The quantitative and qualitative effects of heavy rain point to the high sensitivity of these groundwaters to rain input, which is the principal recharge source of the studied aquifer

Micromechanical modeling of the effect of elastic and plastic anisotropies on the mechanical behavior of β-Ti alloys

International audienceNear β-titanium alloys like Ti-5553 or Ti-1023 often exhibit bimodal phase constituents embedded in a retained β-phase matrix, which represents up to 40% of the volume. The highly elastic anisotropic β-phase may strongly influence the mechanical behavior of these alloys. The present work models the effect of the coupled role of β-phase elastic and plastic anisotropies on the local and overall responses of a fully β-phase polycrystalline aggregate like the Ti-17 alloy. The model is based on an advanced elasto-viscoplastic self-consistent (EVPSC) homogenization scheme solved by the "translated field" method together with an affine linearization of the viscoplastic flow rule. The effects of elastic anisotropy, crystallographic texture and grain morphology are theoretically studied during uniaxial tensile tests, tension-compression tests as well as multiaxial plastic yielding. First, it is shown that different sets of elastic constants taken from literature give rise to similar effective responses but to widely scattered incompatibility stresses. During uniaxial tensile loading, the highest local incompatibility stresses are achieved in oriented grains at the end of the elastic regime. Likewise, the effect of the β-grain morphology for realistic grain aspect ratios is seen to be weak on the overall behavior but strong on incompatibility stresses. In addition, the elastic anisotropy can have a significant influence on yield surfaces for β-forged textured polycrystals. Finally, the simulated Bauschinger stress monotonically increases with the elastic anisotropy coefficient for a random texture while it may be reduced in case of β-forged texture due to a competition between elastic and plastic sources of incompatibility stresses

Determination of the extent of frying fat deterioration using differential scanning calorimetry.

Differential scanning calorimetry was used to assess oil deterioration compared with known chemical parameters. Five different types of edible oils, namely, corn oil, soybean, sunflower, canola and palm olein, were used in this study and banana was used as the fried product. Batches of banana approximately 5-7 cm in length were cut into uniform wedges and then were fried at 180±5°C. The frying was intermittent and continued for 5 hours a day for six consecutive days (a total of 30 hours). The changes in the thermal properties of all used oils were studied and compared. A simple method was developed for monitoring the oil deterioration by DSC based on the heating thermogram of the used oil samples at scanning rate of 5°C/min from -70 to 70°C. The heating thermogram for the oils showed varying degree of changes especially in the major melting peak position during the course of frying. At the end of frying days changes in the peak temperature of the major melting peaks for all the oil was found to increase significantly (P<0.05) from the initial day to the last day of frying, the values were: corn oil (-23.1 to -5.4°C), soybean (-23.5 to -2.2°C), sunflower (-10 to -1.33°C), canola (-10 to -2.7°C) and palm olein (14.6 to 19.9°C). The deterioration of used oil was also assessed by determination of total polar compound (TPC) percent, iodine value (IV), specific extinction E1% at 233 and 269 nm and changes in viscosity (cP). The extent of oil deterioration was best reflected in the changes in TPC percent for all used oils. The changes from the initial to the final values were: corn oil (3.8 to 37.6%), soybean (4.7 to 35.3%), sunflower (3.5 to 32.7%), canola (2.0 to 24.4%) and palm olein (3.3 to 20.5%). There was a good positive correlation between the major peak temperature values from the DSC heating thermogram and the TPC for all the oils tested

Control of composting parameters and assessment of the quality of household waste compost in the Rabat-Salé Wilaya

Les unités de compostage des déchets ménagers se heurtent souvent à des problèmes concernant l'élimination des indésirables et le contrôle du processus de fermentation des décQets putrescibles. Dans cette optique, la présente étude a porté sur (i) l'évaluation de l'efficacité d'élimination des indésirables à l'UTOM (Unité de Traitement des Ordures Ménagères) de la willaya de Rabat-Salé, (ii) l'étude de l'effet de la variable fréquence de retournement des tas sur la processus de décomposition des ordures ménagères ayant subi un broyage et un criblage grossier comme prétraitements préabables, et (iii) l'évaluation de la qualité du compost produit concernant sa composition physique et chimiqtte. L'efficacité d'élimination des indésirables à l'UTOM s'est avérée moyenne, se répercutant ainsi sur la qualité du compost. Cette expérimentation a montré une relation étroite entre le nombre de retournement et la température interne des tas, particulièrement durant les deux premièresJ semaines. L'intervalle optimale d'humidité pour assurer une décomposition aérobique chaude est situé entre 40 à 57%, et la durée nécessaire au processus est d'au moins un mois. Le compost produit se caractérise par une charge importante d'indésirables et de micro-polluants représentés principalement par les éléments traces Pb, Cu et Zn

Stress partitioning in a near-β Titanium alloy induced by elastic and plastic phase anisotropies: experimental and modeling

International audienceThe load transfer induced by the elas c and plas c phase anisotropies of a Ti-10V-2Fe-3Al tanium alloy is studied. The microstructure consists in α nodules embedded in elongated β grains. EBSD performed on the alloy shows no crystallographic texture neither for α nor β phase. Tensile tests along the elonga on direc on, at a strain rate of 2 x 10-3 s-1 give a yield stress of 830 MPa with 13% duc lity. Simula ons based on an advanced two-phase polycrystalline elasto-viscoplas c self-consistent (EVPSC) model predict that the β phase first plas fies with a sequen al onset of plas city star ng from oriented β grains, then and finally oriented β grains. This leads to a strong load transfer from the β grains to the α nodules whose average behavior remains elas c up to high stresses (~940 MPa). However, addi onal simula ons considering exclusively β grains of specific orienta on show that the behavior of α nodules is strongly dependent on the β texture in which they are embedded. Especially, in β grains, which plas fy the latest, the model predicts the onset of plas city in favorably orientated α nodules. Moreover, the orienta on spread within the β grains can modify the average plas c behavior of α phase. In future, these results will be compared to data obtained from in-situ High Energy XRD and SEM/EBSD experiments

Fuzzy-TOPSIS based Cluster Head selection in mobile sensor networks

One of the critical parameters of Wireless Sensor Networks (WSNs) is node lifetime. There are various methods to increase WSN node lifetime, the clustering technique is being one of them. In clustering, selection of a desired percentage of Cluster Heads (CHs) is performed among the sensor nodes (SNs). Selected CHs are responsible for collecting data from their member nodes, aggregating the data and finally sending it to the sink. In this paper, we propose a Fuzzy-TOPSIS technique, based on multi criteria decision making, to choose CH efficiently and effectively to maximize the WSN lifetime. We will consider several criteria including: residual energy; node energy consumption rate; number of neighbor nodes; average distance between neighboring nodes; and distance from the sink. A threshold based intra-cluster and inter-cluster multi-hop communication mechanism is used to decrease energy consumption. We have also analyzed the impact of node density and different types of mobility strategies in order to investigate impact over WSN lifetime. In order to maximize the load distribution in the WSN, a predictable mobility with octagonal trajectory is proposed. This results in improvement of overall network lifetime and latency. Results shows that the proposed scheme improves the network lifetime by 60%, conserve energy by 80%, a significant reduction of frequent Cluster Head (CH) per round selection by 25% is achieved as compared to the conventional Fuzzy and LEACH protocols

Characterization of the Hamra sheep breed in western Algeria

editorial reviewedThe present work is a part of a National Research Project (PNR Algeria 2022) dedicated to the development of the Hamra sheep breed in his cradle western Algeria. The aim of this study is to characterize the morphology, growth and reproductive performance of this ovine breed. A sample of 15 rams and 30 ewes were used for the morphological characterization versus a total of 1,328 head for the growth and reproduction performance carried out at the technical livestock institute in Saida area located in the western Algeria. Hamra sheep breed is small compared to other Algerian breeds. It has a dark brown (mahogany) head and legs, a blackish-blue tongue, white wool, spiral horns, and a fine, medium-length tail. Total body length is 124.5 cm for males and 110.5 cm for females, with a trunk length of 78.6 cm for males and 67.7 cm for females. Depth, width and circumference of chest are respectively 40.3 cm; 30 cm; 116.4 cm for males, and 34.2 cm; 22 cm; 99.8 cm for females. Growth monitoring showed an average birth weight of 3 to 3.6kg, depending on sex (male or female) and litter size (single or double). Live weights reached an average of 17.9kg for males and 16.2kg for females at 90th day of age. The ewes' reproductive performances are as follows: 82.2% for fertility, 97% for fecundity and 118% for prolificacy at birth and weaning. In conclusion, the Hamra breed has shown promise performances in terms of growth, but its butchering potential needs more assessments. Further studies are required to establish a conservation strategy becoming urgent by the uncontrolled introduction of genetics from other sheep breeds.PNR- Algérie12. Responsible consumption and productio

The influence of european norms on civil appeal procedure with compulsory representation

Les normes européennes, qu'elles émanent de l'Union Européenne ou découlent de la Convention Européenne des droits de l'Homme, telle qu'interprétée par la Cour EDH, ont un impact sur l'ensemble de l'ordre juridique étatique des États concernés. Parmi les matières irradiées par le droit européen au sens large, la procédure civile ne fait pas exception mais la matière processuelle demeure traitée de façon singulière par les institutions supra-nationale, à plus forte raison pour la procédure suivie devant les juridictions de recours. Si à raison des ordres juridiques, les normes européennes à valeur supérieure à la loi ont nécessairement une influence sur la procédure civile d'appel, ce n'est qu'en raison de la volonté des autorités françaises que cette influence trouve une réalisation concrète. En effet, au cours de l'adoption de la réforme de la procédure civile d'appel, en 2009, le pouvoir règlementaire a exprimé le souhait d'adopter une procédure d'appel conforme aux exigences européennes du procès civil, en particulier de l'article 6§1 de la Convention EDH et du principe du procès équitable. Pour autant, si cette influence est incontestable, elle se trouve limitée à divers égards. D'une part, l'autonomie procédurale des États a été fermement consacrée par les autorités de l'Union qui ne s'est attribuée aucune compétence en la matière, et la jurisprudence de la Cour de Justice de l'Union. De son côté, la Cour EDH limite son immixtion à cet égard au nom de principe de subsidiarité renforcé par l'adoption des Protocoles additionnels n°15 et 16. Encore, à plus forte raison, le choix du pouvoir règlementaire français, marqué du sceau de la célérité, s'est effectué au détriment certain des autres principes directeurs du procès, en particulier le procès équitable et l'accès au juge, qui se trouvent excessivement amputés par des délais stricts et des sanctions sévères et automatiques. La procédure civile d'appel est devenue une procédure essentiellement calendaire, de gestion de flux contentieux, sans atteindre l'objectif de célérité qui justifiait ces restrictions. Ainsi, au regard des difficultés de délais que connaissent les cour d'appel françaises, il convient de s'interroger sur l'opportunité de consacrer plus largement et de façon effective, les principes européens du procès civil, par l'avénement d'un appel nouveau qui aurait pour objet la remise au cœur de l'équité, du principe du contradictoire, de l'égalité des armes et de l'accès au juge. Pour ce faire, il est possible de se tourner vers les modèles procéduraux des instances judiciaires des institutions européennes, ou encore des exemples procéduraux étrangers. Une telle démarche de rééquilibrage des attentes procédurales permettrait intrinsèquement d'opter pour une procédure plus vertueuse et respectueuse des droits procéduraux des justiciables, et sans doute également, d'améliorer les délais de procédure devant les cours d'appel. Dans une telle perspective, il convient de s'interroger sur l'appel dans sa globalité, mais également sur l'intégralité du procès civil. Quant à la philosophie de l'appel, il semble que la voie d'achèvement soit le meilleur modèle afin d'atteindre ces objectifs, dans un cadre strict qui permette d'exclure les abus et la déloyauté des parties. Ainsi, par différents mécanismes de filtrage et l'adoption d'une instruction plus souple, il serait possible de concilier les exigences du procès équitable et de la célérité, ouvrant la voie d'une influence totale des normes européennes sur la procédure civile d'appel avec représentation obligatoire.European norms, whether they emanate from the European Union or derive from the European Convention on Human Rights, as interpreted by the EDH Court, have an impact on the entire state legal order of the States concerned. Of the materials irradiated by European law in the broad sense, civil procedure is no exception, but procedure remains treated in a singular way by both European institutions, even more concerning appeal courts. If, by reason of the legal systems, European norms with a higher value than the law necessarily have an influence on the civil appeal procedure, it is only because of the will of the French authorities that this influence finds concrete realization. Indeed, during the adoption of the reform of the civil appeal procedure in 2009, the regulatory authority expressed the wish to adopt an appeal procedure that complies with the European requirements of the civil trial, in particular Article 6§1 of the EDH Convention and the principle of fair trial. However, while this influence is indisputable, it is limited in various respects. On the one hand, the procedural autonomy of States has been firmly enshrined by the authorities of the Union, which has not given itself any competence in the matter, and the jurisprudence of the Court of Justice of the Union. For its part, the EDH Court limits its interference in this respect in the name of the principle of subsidiarity reinforced by the adoption of Additional Protocols Nos 15 and 16. Even more so, the choice of French executive power, marked by the seal of celerity, was made at the expense of certain of the other guiding principles of the trial, in particular the fair trial and access to the judge, which find themselves excessively cut off by strict deadlines and strict and automatic penalties. The civil appeal procedure has become essentially a calendar procedure for managing litigation flows, without achieving the objective of celerity that justified these restrictions. Thus, in view of the difficulties of delay experienced by the French Courts of Appeal, it is necessary to consider the advisability of devoting more broadly and effectively the European principles of civil litigation, by the advent of a new appeal that would have as its object put in center fairness, the principle of the contradictory, the equality of arms and access to the judge. To do this, it is possible to turn to the procedural models of the judicial bodies of the European institutions, or even to foreign procedural examples. Such an approach to rebalancing procedural expectations would make it possible to opt for a more virtuous procedure that respects the procedural rights of litigants, and probably also, to improve the time it takes in front of appeal courts. In this perspective, it is necessary to question the appeal in its entirety, but also the totality of the civil process. As for the philosophy of the appeal, it seems that the « way of completion » is the best model in order to achieve these objectives, within a strict framework that makes it possible to exclude abuses and disloyalty of the parties. Thus, through different filtering mechanisms and the adoption of a more flexible instruction, it would be possible to reconcile the requirements of fair trial and expediency, opening the way for a total influence of European standards on the civil procedure of appeal with compulsory representation