Vers la valorisation de la pulpe du fruit d arganier

Transcription

1 1 Vers la valorisation de la pulpe du fruit d arganier Alternative à l actuelle filière fragile mono-produit de l huile d argan Pioch D. 1, Palu S. 1, Buland F.N. 1, Pingret D. 1, Dumas J.C. 1 Harhar H. 2, Charrouf Z. 2 Benismail M. C. 3, Mokhtari M. 3 1 CIRAD, Montpellier, France 2 Université Mohammed V, Rabat, Maroc 3 IAV / Agadir, Maroc

2 Rationale 2 Economic sustainability of current argan production chain? Because - based on a single product (argane oil from the nut) - for fashion-linked markets (cosmetics, health foods) => Need to diversify the panel of products derived from fruits: - Cake after oil extraction (feed) - Nut shell (fibers for composite materials; energy) - Pulp: - major component of fruit - known potential source of valuable products - much less investigated than the nut (and argane oil) => Need a better knowledge of the pulp for an improved valorization of the whole fruit -> Argan Biorefinery

3 Summary 3 Objectives Investigate technical aspects for producing intermediate fractions from fruit Method Collect fruit samples under controled conditions Biometry and composition (pulp%; biochemicals) Investigate : drying options for stabilizing the fruits simple mechanical depulping (fresh fruits) Conclusion & prospect in view of setting a biorefinery

4 Harvest 4

5 Protocol for collecting ripe fruits 5 Ripe fruits Considered ripe when falling on the ground Collected daily on PE film for 2-3 weeks: Limit pollution (soil, insects, micro-organisms) Argan tree at IAV-Agadir

6 Protocol for collecting unripe fruits 6 Fruits collected at 3 stages of ripening visual estimation of color Almost ripe => close to falling but not yet Intermediate => changing color green + yellow Unripe => still green Infested fruits Fruit shape Apiculés Ovales Ronds Fusiformes

7 Pulp (+peel) % and composition 7

8 Pulp % in fruit vs Ripeness Pulp in fresh fruit (%) 15 % relative variation during ripening

9 Pulp % vs fruit form Ripe fruits 9 - Pulp in fresh fruits: 20% relative variation within trees of same shape => Trees should be selected according to pulp content - Dry pulp weight: %dw vs fruit shape => Compared to ~6 %dw of kernel (or argan oil ~3%dw)

10 Water in pulp vs ripening Water + Volatile (%) - Water content in pulp is very high => Care for preservation during storage: dehydration or processing upon harvest

11 Oil in pulp vs ripening and shape Oil in pulp (% dw) Oil in pulp (% dw) Pointed Fusiform Round - Oil content in pulp varies a lot vs fruit form - Oil content is 35%dw higher before fruit falls - Up to 8,4 %dw of oil in dry pulp - Pulp oil 4 % / argan oil ~3 %, based on dry fruits => Trees should be selected according to pulp composition

12 Main conclusions about pulp in fruit 12 Pulp oil + latex 5% > argan oil 3%, based on fruit dry weight Variability of pulp % and composition, water% => This may bring technical constraints for processing

13 13 Drying (for stabilization) No direct sun-light (photochemical degradation) Whole fruit / separated pulp Solar tunnel 30 C / electric oven 40 C

14 Drying: electric loop 14 Degraded (dark) pulp alone Whole fruit 120 Sample weight 100 (%) C 1day -> Aw < 0.5: full stabilisation - Cost of oven >> Solar tunnel => Suitable for long storage time Pulp oven Hours 80

15 Drying: ventilated solar tunnel 15 Electric fan - Tunnel located close to the field, reduced transportation cost - Soft temperature (< 32 C), no light, - ~50% pulp water loss in 7days (acts mainly on pulp, less on nut) => Suitable for short storage time before delivery to processing plant

16 Mechanical depulping 16

17 Whole-fruit processing to pulp, peel, nut 17 Rotating blades Horizontal mesh cylinder Nut and peel outlet Pulp paste container Nut Peel Very simple hardware 10kg/h capacity, can be expanded x 100

18 Whole-fruit processing to pulp, peel, nut 18 Not depulped because of short cylinder mesh in pilote Low ratio of broken nuts (suitable for Argan oil quality)

19 Whole-fruit processing to pulp, peel, nut 19 Type of processed fruit (% water) Depulping fractions (% weight of fruits) Pulp Peel Nut Not depulped because of short cylinder mesh in pilote Dried 16 days Dried 7 days Fresh Low ratio of broken nuts (suitable for Argan oil quality) Water content in fruits: a key parameter to be optimized in conjunction with stabilisation option => Mechanical depulping works well in spite of heterogeneity (shape, size)

20 Projected alternative production chain 20 Small farm or Cooperative Processing plant small, large size Products local + export Harvest of fresh fruits Optional drying Half dried Fresh Depulping step Pulp Kernel Peel?

21 Projected alternative production chain 21 Small farm or Cooperative Processing plant small, large size Products local + export Harvest of fresh fruits Optional drying Half dried Fresh Depulping step Pulp Kernel Peel Screw press Virgin Argan oil Cake (goat feed)? Current oil extraction plant

22 Projected alternative production chain 22 Small farm or Cooperative Processing plant small, large size Products local + export Harvest of fresh fruits Optional drying Half dried Fresh Depulping step Pulp Kernel Peel Screw press Virgin Argan oil Cake (goat feed) => Argan Biorefinery Size of processing plant can be adjusted New products? Essential oil (flavor) Latex (glue, chewing gum) Pulp oil (soap) Bioactive (health, anti-insect) Bagasse (goat feed) New products Wax Bioactive (?) Bagasse

23 Conclusion / Pulp 23 - High chemical diversity in the pulp (this work and litterature data) Market value compared to fodder - New food products x 10 - Functional extracts (additives) x 50 - Bioactives compounds (health, agriculture) x Total value of products > Production cost >> Fodder (current use of pulp) Research work -> Technical options -> Pilote plant

24 Prospect 24 To take advantage of pulp phytochemical diversity Selected trees, controled harvest, fresh-fruit processing => Apply the Biorefinery concept Panel of products Shared costs easier when building a new plant and a new crop A chance for Argan!

25 25 Remerciements ADS Maroc, pour le financement des travaux CIRAD, Agropolis-International, Univ. Mohammed-V, IAV-Agadir Les chercheurs et étudiants qui ont participé à l ensemble du projet Dr Frédéric Bonfils, CIRAD UMR IATE, Montpellier Dr Badr Eddine Kartah & Miloudi Hilali, Université Mohamed-V Rabat

26 - Prospect for whole-fruit processing to a full range of products 26 Biomass availability Which argan parts? Almond + Husk + Pulp Leaf + Wood Targeted markets Which products? Food: Exotic aroma, ice-cream, health-food Non food: rubber, glue, soap Additives, activated C Energy Processing options Derived from oil palm? Modern extraction techniques? µ-waves, U-Sound, Super-critical CO2, H2O Low environmental impact

27 Pulp oil acidity vs ripening Oil acidity (oleic %) Very high acidity when unripe (16%), still high when ripe (9%) Not suitable for refining -> manufacture of Argan soap? containing bioactives in unsaponifiable

28 3- Influence of ripening / soluble sugars Glucose Fructose Saccharose 28 - Soluble sugars : fast increase during last month ripening 4 to 17 % dry pulp - Saccharose: 1.0 to 7,5% in 1 month only => Marker of maturity -> harvesting date in Argan fields?

29 4- Influence of form / soluble sugars Total extracted sugars Pointed Fusiform Round - Soluble sugars vary vs fruit shape mg/g dry pulp Glucose Fructose Saccharose Pointed Fusiform Round - Main sugar can be saccharose or glucose depending on fruit form => Easy differenciation of genotypes - phenotypes?

30 5- Influence of ripening / cell wall sugars mg/g Unripe Ripe Glucose Rhamnose Xylose Mannose Galactose Arabinose - Total cell wall sugars : drastic change in 1 month - Jump of extract from 138 to 250 mg/g dry pulp - Decrease of C5 (markers of primary wall) => formation of fibers (glucose C6) => Strong Influence on pulp processing & quality of final products