V. C. LAGOU ^1*

N. Y. KONAN ²

R. R. ASSA ¹

¹ Laboratory of Biochemistry and Food Sciences, Training and Research Unit of Biosciences, Felix Houphouët Boigny University, 22 PO Box 582 Abidjan, Côte d’Ivoire

² Biochemistry and Genetics Department, Training and Research Unit of Biological Sciences, Peleforo Gon Coulibaly University, PO Box 1328 Korhogo, Côte d’Ivoire

Abstract – The orange (Citrus sinensis L.) are of edible fruits enjoyed in Côte d’Ivoire thanks to their delicious taste and nutritional properties. However, during the orange fruit consumption, the peels, membranous endocarp and seeds are residues considered as garbage and therefore thrown away. The current report focuses the physicochemical and nutritive parameters of the residues deriving from this citrus fruit in order to search ways for their valorization. The investigation was performed using orange collected in four (4) communes from Abidjan District, Southern Côte d’Ivoire. The data show homogeneous rates per type of residue whatever the origin of oranges, with means of 10.97% peels, 12.48% membranous endocarp and 6.26% seeds from the full fruit weight. Overall residues samples felt acid, displaying pH values between 4 and 5. The nutritive composition varies according to the type of residue and the fruit origin. Proteins are more accumulated in orange seeds (7.12 to 27.44 mg/100 g) compared to the endocarp and peels (4.34 to 8.51 mg/100 g). The seeds are also more provided in lipids (20.22 to 37.74 g/100 g) and fibre (21.18 to 33.45 g/100 g) from overall origins; whereas peels displayed higher ash content (5.34 to 7.06 mg/100 g). On the other hand, the orange residues deriving from each commune record unvarious glucides content. Otherwise, the peels are more provided in polyphenols compounds, specifically for oranges collected from plateau commune (444.89 mg/100 g). The oranges peels and membranous mesocarp could be valorised as sources of minerals and polyphenols since they account greater ash and polyphenols contents; whereas the oranges seeds could support the production of essences and could record other functional properties regarding their significant fat matter, protein, and fibre contents.

Keywords: Citrus sinensis, residues, physicochemical properties, valorization, Côte d’Ivoire

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Déterminants d’adoption de référentiels de sécurité sanitaire des aliments chez les exportateurs tunisiens de dattes

H. ALLANI*¹

A. LAAJIMI¹

A. ROMDHANI¹

¹ Institut National Agronomique de Tunisie. Département d'Economie, Gestion Agricole et Agroalimentaire.

Abstract – Although Tunisia is the world's largest exporter of dates in terms of value, it is currently facing increased competition which requires it to give more importance to the "non-price competitiveness" aspect in order to preserve, at least, its market share. Indeed, with the tightening of international food safety (FS) requirements, the compliance of this industry with FS standards has become a necessary step to ensure access to growing markets. However, survey data from 42 Tunisian dates’ processing-exporting companies show that 24% of them are non-adopters. In this context, the present empirical study proposes to analyze the strategic behavior of this type of operators by identifying the factors that influence their decisions to adopt or not FS standards. The analysis tool consists of a binary logistic regression model with binary dependent variable "Adoption / Non-adoption of FS standards". Among the main results, we find that internal and objective factors such as "size" and "training in good manufacturing / hygiene practices already carried-out" have a positive and significant impact on the probability of adoption. It also appears that, the more reason for the adoption "meeting regulatory / customer requirements" is perceived important by these operators, the more their propensity to adopt increases. This external and subjective factor is, in fact, the most significant independent variable of the model.

Keywords: Tunisia, dates export, standards adoption, food safety

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Quelle est la réponse de l’orge (Hordeum vulgare L. ssp. vulgare) face aux éléments traces métalliques, zinc, cuivre et cadmium?

O. AYED SLAMA *¹

I. BOUHAOUEL¹

S. NAOUAR¹

H. SLIM AMARA¹

¹ University of Carthage, National Agronomic Institute of Tunisia, Department of Agronomy and Plant Biotechnology, Genetics and Cereal Breeding Laboratory, 43 Charles Nicolle Street, 1082 - Tunis Mahragene, Tunisia.

Abstract – Soil pollution by metallic trace elements (MTE) requires an assessment of the risk of toxic effects in the most consumed plant species, in particular barley (Hordeum vulgare L. ssp. vulgare). This study aimed to assess the toxic effect of three MTE, zinc (Zn), copper (Cu) and cadmium (Cd) on the growth of two barley varieties cultivated in hydroponics, Rihane and Manel, and their accumulation potentials of these pollutants. After 14 days of culture, barley seedling growth, estimated by leaf and root length and fresh and dry weight, was reduced (25.25, 7.70, 78.56 and 66.47%, respectively). Toxic effects were more pronounced on fresh and dry biomass compared to the leaf and root length. Cu and Cd were the most toxic elements. However, the tested MTE have slightly reduced the relative water content in both varieties. Taking into account these morphological and physiological parameters, Manel was more sensitive to these elements than Rihane. The accumulation of trace metals in these plants increased according to their contents in nutrient solutions and followed the decreasing order Cu> Zn> Cd. Under these conditions, Manel accumulated a little more MTE (BCF = 1.61) than Rihane (BCF = 1.46) but the difference was not significant between these two varieties. Taken together, these results suggest that Manel is less recommended for MTE-contaminated areas.

Keywords: Metallic trace elements, Hordeum vulgare L. ssp. vulgare, hydroponics, cadmium, copper, zinc.

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I. GHARIANI^1,2

O. ELASRI³

H. LAICHE³

T. NAJAR^1,2

¹ Animal Production Department, National Agronomic Institute in Tunis, University of Carthage, Tunis, Tunisia

² Laboratory of Materials Molecules and Applications, Preparatory Institute for Scientific and Technical Studies, University of Carthage, Tunis, Tunisia

³ Biochemistry and biotechnology Laboratory, Mohamed First University, Oujda; Morocco

Abstract – Several wastes can be treated by Anaerobic Digestion (AD) to minimize their adverse effects. Different parameters can affect the wastes valorization such as their origin, as well as the used processes and devices. The purpose of this study is to compare two experimental devices for biogasmeasurement and to select the best for its biogas production and laboratory scale operation. The substrate chosen for this study is glucose with the addition of poultry digestate as an inoculum. The use of erlenmeyer as gasometer filled with wateris often inconvenient for various reasons, namely gas solubility in water and water evaporation and also the difficulty of passing the produced gas especially with low flow rate up to the gasometer. Also, we followed the kinetics of the volume of biogas produced by each device as a function of time and the degradation of Organic Matter (OM). The use of the device with the gasometer formed by reverse graduated burette filled by the barrier solution occur the best results in terms of maximum amount of biogas produced, minimization of the reduction of the pH during the AD and the biodegradation of the OM a recorded an important value which confirms the good performance of this device. These results allow us to conclude that the choice of the second digester for starting experimental AD can minimise gas solibility and promotes the stabilization of optimal conditions of AD.

Keywords: Experimental device, Anaerobic Digestion, Glucose, Biogas

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T. AZIZI-GANNOUNI^1,2*

T. BARRENECHE³

J. QUERO-GARCIA³

J. ANTONIO CAMPOY³

I. OUERGUI⁴

A. ALBOUCHI²

 Y. AMMARI²

¹ Faculty of Mathematical, Physical and Natural Sciences of Tunis, Compus El manar 2092, University of El manar, Tunisia.

² National Researches Institute of Rural Engineering, Water and Forests, Tunis (INRGREF), University of Carthage, Tunisia.

³ INRA Bordeaux UMR1332 fruit biology and pathology (BFP), Villenave d’Ornon Cedex, France.

⁴ National Institute for agricultural Research (INRA), University of Cartage, Tunsia

Abstract – Sweet cherry (Prunus avium L.) is a species that is characterized by gametophytic self-incompatibility (GSI), which determines the fruit set and, consequently, the tree fruit load. In this study, S-alleles have been identified for nine sweet cherry cultivars in north-western Tunisia. We genotyped 9 cultivars (five introduced unknown cultivars, three international ones and one local ‘Bouargoub’) and we found 2 new Tunisian sweet cherry S-haplotypes (S₂ and S₁₀) using polymerase chain reaction (PCR) based on length polymorphism detection of S-RNase and SFB genes. Most introduced sweet cherry cultivars are self-incompatible and cross pollination is necessary to ensure the fruit set. However, the local one “Bouargoub” was considered to be self-compatible. The haplotypes S₂and S₁₀ was less frequent, whereas S₃ was the most frequent (44.44%) in the nine studied cultivars.

Keywords: Prunus aviumL.; polymerase chain reaction; S-RNase; Fruit set

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