W. Abidi^1*

J.L. Zeballos²

R. Giménez²

M.A. Moreno²

A. Granell³

Y. Gogorcena²

¹ Centre Régional de Recherches Agricoles (CRRA), Sidi Bouzid, Tunisia.

² Estación Experimental de Dei (EEAD-CSIC), Zaragoza, Spain.

³ Instituto de Biología Molecular y Celular de Plantas (IBMCP-CSIC-UPV), Valencia, Spain.

Abstract - Fruits contain significant levels of biologically active components with physiological and biochemical functions which benefit human health. Epidemiological studies suggest that consumption of fruit rich in phenolic compounds is associated with health-protective effects due to their antioxidant properties. For these reasons quality evaluation has become an important issue in fruit industry and in breeding programs. Phytochemical traits such as total phenolics, flavonoids, anthocyanins, L-ascorbic acid, relative antioxidant capacity (RAC), total sugar content and volatiles compounds were analyzed over four years in flesh fruit of an F1 population “Venus” × “Big Top” nectarines. The objective of this study was to select superior genotypes with enhanced antioxidant capacity, total sugar content and aroma in fruits that will benefit consumers with health-promoting properties. Results indicate that nectarine fruit is a good source of phenolic compounds and highlight the fact that ascorbic acid content is an important part of the overall evaluation of peach fruit quality. Over 60 volatiles compounds were successfully profiled, including 10 carboxylic acids, 10 aldehydes, 5 alcohols, 3 esters, 12 ketones, 8 lactones and 12 terpenoids. The progeny showed high total phenolics and flavonoids content, and a significant aroma profile this fact could be very interesting in the peach genotype selection process.

Keywords: antioxidant capacity; flavonoids; total phenolics; vitamin C, volatiles compounds

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A. BOUSSAID¹

M. CHOUAIBI¹

R. MISSAOUI³

F. DONSͲ

G.FERRARI²

S. HAMDI¹

¹ Food Preservation Laboratory, High Institute of Food Industry, 58 Alain Savary street, Elkhadra city, Tunis 1003, Tunisia.

² Department of Chemical and Food Engineering, University of Salerno, Via Ponte Don Melillo, 84084 (SA), Italia.

³ Département des Sciences des Aliments et de Nutrition, Pavillon Paul-Comtois, rue de l'Agriculture, Université Laval, Québec (Québec) G1V 0A6.

Abstract - The present study was undertaken to determine the physicochemical of three Tunisian honey samples from various floral origins (eucalyptus, rosemary, and thyme). In this study water content, water activity, pH, acidity free, electrical conductivity (EC), ash, invertase activity, Hydroxymethylfurfural content (HMF), fructose, glucose and sucrose were all determined in different types of bee honeys. The water content varied from 15.21 to 19.12%; the water activity between 0,56 and 0,61, pH between 3.64 and 3.96; the free acidity ranged between 7.63 and 26.76 meq kg^-1; hydroxymethylfurfural (HMF) content shows values between 12.81 and 30.72 mg kg^-1; invertase values were between 60.39 and 115.23 unité kg^-1 ; electrical conductivity between 0.39 and 0.66 mScm^-1; ash between 0.07 to 0.4; fructose between 38.31 and 44.49%; glucose between 25.83and 35.98% and sucrose between 2.85 and 4.46%. The results showed that all honey tested are significantly in terms of physicochemical properties, HMF, Invertase activity and sugar composition. All the extracted honey samples appeared to conform to the European Legislation (EC Directive 2001/110).

Keywords: Tunisian honeys / monofloral honeys / physicochemical properties / quality.

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S. Arroum* ¹

K.Zmouli ²

A.Gaddour ¹

I.Fguiri ^1,2

N.Ayeb ¹

T.Khorchani ¹

¹ Laboratoire d’élevage et de faune sauvage, Institut des Régions Arides, Médenine, Tunisie

² Institut Supérieur de Biologie Appliquée à Médenine, Tunisie

Résumé - La présente étude a pour objectif d’étudier la qualité des caractéristiques physico-chimique et microbiologique du lait camelin en fonction du mode d’élevage. Le lait a été prélevé des 20 chamelles (race Maghrebi) appartenant à 3 systèmes d’élevage (intensif, semi-intensif et extensif). L’étude comparative des caractéristiques physico-chimiques du lait a montré que le lait de la chamelle en système extensif est plus riche en matière grasse (42.87±14.53 g/), matière sèche (141,5 ±23,68 g/l), matière minérale (8,71 ±1,56 g/l) qu’en système intensif et semi-intensif. Ainsi le lait de chamelle en système extensif est plus acide par rapport à celui dans les deux autres systèmes L’étude comparative des caractéristiques microbiologiques a montré que le lait camelin en système extensif est plus chargé en flore aérobie mésophile totales (7,07±1), en levures et moisissures (6,5±1). La qualité du lait camelin est affectée par le mode d’élevage.

Mots clés : Lait de la chamelle, caractéristiques physico-chimiques, caractéristiques microbiologiques, système d’élevage.

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A. Tarhouni ¹ 

N. Ben Miloud ²

E. Mtar ¹

S. Sadok ³

N. Mihoubi Boudhrioua ¹ *

¹ UR11ES44, Ecophysiologie et Procédés Agroalimentaires, Université de la Manouba, BP-66, 2020 Ariana, Biotechnople Sidi Thabet 2020 Tunis, Tunisie

² Laboratoire des Applications Médicales et Agricoles des Techniques Nucléaires, Direction de Recherche Environnement et Vie, Centre National des Sciences et Technologies Nucléaires, CNSTN, Biotechnople Sidi Thabet 2020 Tunis, Tunisie

³ Laboratoire de Biodiversité et Biotechnologie Marines, Institut National des Sciences et Technologies de la Mer, la Goulette, Tunis, Tunisie

Abstract - The aim of this study is to investigate the effect of combined drying and gamma irradiation processes on the final quality of muscles and byproduct powders of round sardinella Sardinella aurita. Sardinella muscles with fishbone were dried at 75°C while byproducts (heads and viscera) were cooked at 90°C, pressed and dried at 75°C. Such process allowed decreasing moisture content of the muscles (from 73.38 ±1.01% to 3.295±1.05% -wet basis) and of the byproduct (from 70.00±0.85% to 6.40±0.90% -wet basis). Dried muscles and byproduct powders undergo gamma irradiation at 5 and 10 kGy doses in a Co-60 d-irradiator. Microbial analysis (coliform bacteria, Escherichia coli, mesophilic bacteria, pseudomonas, and sulfite-reducing bacteria, yeasts and molds) were performed to investigate products stability at room temperature. The pH values of muscle and byproduct powders were 6.15±0.14 and 5.86±0.06 respectively. Such values were maintained constant after 42 days of storage at room temperature for irradiated byproduct powders (5.80±0.03 for 5kGy and 5.90±0.02 for 10 kGy); whereas, the pH of the 5kGy-irradiated muscles powder decreased to a value of 5.99±0.03. The global color difference of irradiated muscles and byproduct powders showed little variations during storage at room temperature. The microbial analysis showed that the non-irradiated byproduct powder was more salubrious that non-irradiated muscles powder and this could be attributed to cooking operation of the byproduct before drying. The irradiation of both products at 5 and 10 kGy doses provided products with acceptable color and microbial quality.

Key words: Sardinella, Muscles, Byproduct, Drying, Irradiation, Quality

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J. Litaiem ^1,2 

D. Mihoubi ³ 

A. Touil¹ 

F. Zagrouba ¹

¹ High Institute of Sciences and Environmental Technology Borj-Cédria.

² National Agronomical Institute of Tunisia.

³ Thermal Processing Laboratory, Research and Technology Centre of Energy, Hammam-Lif, Tunisia

Abstract- The thin-layer infrared drying behavior of garlic was experimentally investigated in the temperature range from 40°C to 70°C. The drying rate was found to increase with temperature, thus reducing the total drying time. Based on the simultaneous heat and mass transfer, a mathematical model was proposed for predicting the temperature and moisture distribution in the drying sample, applying Fick diffusion equation. A numerical solution was developed for the proposed model using an implicit finite difference method in bi-dimensional system. The main objective of this paper is to formulate an accurate transport model analyzing the simultaneous transfers of heat and mass within garlic slices. The suggested model takes into account garlic deformation and determines the time and space evolutions of moisture, temperature and solid displacement within garlic slices.

Key Words: Garlic, Infrared Drying, Heat and mass transfer, modelisation

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F.E. ZAHROU^*

K. EL KARI

I. EL MENCHAWY

R. ZIRI

H. AGUENAOU

Joint Unit of Nutrition and Food Research (URAC39), CNESTEN-Ibn Tofaïl University, Morocco. Regional Designated Center for Nutrition (AFRA/IAEA)

Abstract - Because iodine deficiency affects 2 billion persons worldwide, its elimination is considered as a global health priority. Inadequate daily intake of iodine can lead to iodine deficiency which can alter physical and mental functions and accelerate cognitive impairment of schoolchildren. Our study aims to determine the iodine status of Moroccan schoolchildren as well as their dietary habits and frequency of consumption of foods that are considered as good sources of dietary iodine, including iodized salt. In an observational study 182 children (aged 7–9 years) were selected from 3 primary schools situated in rural mountainous areas of Morocco. Answers to an adapted food frequency questionnaire and data regarding socio economic status were obtained at the beginning of the survey. Random urine samples were collected in the morning to assess urinary iodine using the Sandell-Kolthoff reaction. Our results showed that iodine deficiency was prevalent in schoolchildren, 82.7% of subjects had an urinary iodine concentration (UIC) <100µg/l and the median of the urinary iodine concentration was found to be 59.6µg/l. Overall, the study population has limited resources and more than 60% spend less than 110 US $ for food monthly. Analysis of dietary habits of children relative to consumption of foods rich in iodine showed that 95% of families did not use fortified salt, 30% of schoolchildren did not consume dairy products, 100% did not eat shellfish and 10% did not eat fish. However 59.16% were consuming fish at least once a week. The schoolchildren living in high altitude rural areas of Morocco have an unbalanced nutritional profile resulting from a monotonous diet of poor quality which can cause various health hazards.

Key words: Urinary Iodine Concentration, Iodine deficiency, rural region.

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