UTILIZATION AND PRESERVATION OF UIVS THROUGH VALUE ADDITION

1. UTILIZATION AND PRESERVATION OF UIVS THROUGH VALUE ADDITION • REPORT ON VALUE ADDITION TO UIVS - CONTRIBUTION TO FOOD SECURITYNICANVEG PROJECT 106511: INDIGENOUS

2. Utilization and Preservation of UIVs through value addition Team members: K.A. Taiwo– ObafemiAwolowo University M.G. Scanlon– University of Manitoba D.J. Oyedele -ObafemiAwolowo University O.C. Adebooye– Osun State University T.O. Bouman – Cape Breton University O.O. Akinremi - University of Manitoba O.O. Ojo- ObafemiAwolowo University O. Oladipo- ObafemiAwolowo University R. Alao – Helping Hands

3. Introduction/Background Traditional Vegetables are rich in micronutrients • High metabolic rates - highly perishable • Lack of storage facilities • Heavy losses in the production and post-harvest handling procedures • Inadequate infrastructural marketing facilities • Need for preservation and storage methods to ensure prolonged availability • Inadequate supplies of desired quality raw material • Limited consumption due to presence of anti nutrients

4. Objectives This work involves • The development of post-harvest methods for preservation and processing of the products • Using technologies that can be readily adopted by local farmers and end users

5. Specific Components • Studies on nutrient retention of processed UIVs • Studies on preservation of snake tomato • Processing and utilization of dried UIVs • Value addition – product development • Development of dryer

6. The Leafy Based Vegetables – • Come in different shapes and sizes • contain some unpalatable components - e.g. • bitterness but can be removed • Tough texture • consumed fresh - but occasionally preserved by drying

7. Vegetables of interest • Ewuro - Bitter leaf- Vernoniaamygdalina • Ugwu -Telfairiaoccidentalis (Fluted Pumpkin) • Igbagba -Solanummacrocarpon • Egunmo • Teteabalaye • Worowo • Ebolo

8. Studies on Debitteringof Bitter leaf Problem – • Limited consumption due to excessive bitterness • Preprocessing to reduce bitterness • No data on effect of debittering methods on nutrient content • Methodology: • Boiling with and without salt (10 - 20 minutes) • Squeeze washing with and without salt and/or trona for 10 - 20 minutes • Blanching with and without salt and/or trona for 20 - 40 minutes • Analysis – Ca, K, Mg, P, Fe, Mn, Protein, vitamin B1, B2, B6, B12 tannin, total phenol and oxalates

9. Results • The mineral content - significantly decreased (p< 0.05) by various pre-treatments • Ca - increased by 7.3 - 25 % with the boiling treatments • % reduction was minimal on K content of the vegetables boiled with trona (25.7 to 35.1%) compared with (44.8 to 55.7%) reduction in other pre-treatments. • Pretreatments caused a significant decrease of 15 - 40 % in the content of vitamin B1, B2, B6 and B12 with highest reduction of 50 to 80 % in the sample boiled with trona • The result of anti-nutritional content followed the same trend with vitamin B complex.

10. Blanching resulted in the least percent loss Squeeze washing gave the highest mineral losses. Effect of time was not highly significant on nutrient loss The addition of salt or trona more than doubled protein losses Squeeze washing achieved the highest reduction in the anti-nutritional contents Blanching with salt reduced bitter compounds by about 50%, while minimizing nutrient losses. Use of salt/trona increased vitamin losses significantly  

11. Recommendation • A compromise between nutrient loss and reduction in bitterness is required during processing of bitter leaf • A compromise best achieved by blanching with salt

12. Influence of Pretreatments on some Nutritional and Anti-nutritional Contents of Solanummacrocarpon (Gbagba) Problem –tough texture Pre-processed to soften & preserve colour No data on effect of processes on nutrient content objective – determine the effect of processing methods on nutrient content of the leaves • Methodology: • Boiling with and without salt (10 - 20 minutes) • Squeeze washing with and without salt and/or trona for 10 - 20 minutes • Blanching with and without salt and/or trona for 20 - 40 minutes • Analysis – Ca, K, Mg, P, Fe, Mn, Protein, vitamin B1, B2, B6, B12 tannin, total phenol and oxalates

13. Results % reduction in samples boiled or squeeze washed with salt Anti nutrients • Tannin 49.14 - 54.46% • Total phenol 43.61 - 60.67 • Oxalates 31.67 - 58.34% Minerals • Samples boiled - 6.78 - 46.35 % • Squeeze washed 4.53 - 41.20 % (with or without salt) • Calcium decreased by 3.9 - 12.08 % • Nutrients retained after pretreatment were adequate to meet the dietary recommended allowance except for phosphorus and iron • Avoid processing of vegetable beyond 5 minutes • Use of salt during boiling should not be encouraged for maximum nutrient retention

14. Studies on Snake Tomatoes(Tricosanthescucumerina)

16. Drying of Snake Tomato • Drying methods – • sun drying • oven drying 50 – 70oC • Water absorption capacity of dried products • Physico-chemical properties • Sensory acceptability of the product

17. Physico-chemical properties of dried tomatoes

18. Studies on Snake Tomato Puree Objectives • Process the fruit into a paste • Determine the physico-chemical properties (moisture content, color, mineral, pH, vitamin C, TTA) of the paste • Determine the influence of different types of oil and salts on the storage stability of the paste • Monitor microbial changes in the stored paste

19. METHODOLOGY • Tomato fruits were washed, pulped and screened manually • Concentrated at 100°C for 15 minutes in an open pot • NaCl ( 5% W/W) or Na- Benzoate (0.07% W/W) were used as a preservatives • Hot filled into glass containers • Top with oil: Palm oil or Canola oil (25ml) to 60g of snake tomato paste • Cooled and stored at room temperature Oludemi (2003) and Nwarekezi and Onyeali (2005)

20. Snake tomato paste

21. Results • Proximate composition – values within literature range • Addition of salts decreased Ca • Na-Benzoate decreased Phosphorus • Mg & K not affected by addition of salt or oil • Mineral values stable in 6wks of storage

22. Lycopene content • 7.4 – 54.9 mg/g • Decreased with storage time • NaCl & Canola oil caused a decrease • Na benzoate & Palm oil caused an increase

23. Vitamin C content • 0.25 – 1.71 mg/g • Addition of salts- increased the Vitamin C content • Presence of oils decreased Vit C • Higher Vit C in palm oil topped samples > canola oil • Vit C increased up to 4wks

24. pH Values • pH values – 4.7 – 5.1 • Stable up to 4wks • Effect of type of salt or oil not significant

25. Total Titratable Acidity (TTA) • 0.71 – 1.03 • Decreased with storage time • TTA in samples with no salts > Na-Benzoate samples >> NaCl samples • TTA in samples topped with palm oil > no oil > Canola oil

26. Total Soluble Solids (TSS) • TSSincreased slightly with storage time • Addition of salts increased TSS • TSS in NaCl >> Na-Benzoate samples • Oil topping increased TSS of the samples • TSS in canola oil >> palm oil samples • Least TSS in samples with no salts

27. Peroxide Value • 0 – 13.75 • PV increased up to 4wks then stabilised • PV of samples with Canola oil >> palm oil • Addition of salt increased PV • PV of samples with Na-Benzoate >> NaCl

28. Microbial Growth • Bacteria count >> yeast & mold count • All microbial counts were within safe limit • Addition of salts &/or oils limited microbial growth to a very minimal level up to 4 wks • Combined use of salt & oil no advantage • NaCl > Na-Benzoate > no salt • Growth higher in samples with canola oil

29. Summary of Results

30. Conclusion • Use of salts &/or oils limited microbial growth up to 4 wks • Oils are better than salts (palm oil preferred)

31. Market Analysis (Feasibility Studies) • Conduct engineering economic tests on the feasibility of production costs and the packaging options • Determine the profitability of the products at different number of operation days and varied plant capacities

32. Engineering economic studies • Production snake tomato puree in cans and sachet • 200g puree– • cans -N40 • sachet - N55 • Market samples in sachet cost about N20 for the 70g pack • These results suggest that the industrial production of the snake tomato puree would be a very profitable venture.

33. Cooking tests • Recipe formulation

34. Drying of the Vegetables Objective – determine the best form to dry vegetables Samples - Teteabalaye, ugu and igbagba Methods - • Sun drying • Blanching (with or without salt) Findings - Visual observations • Significant discoloration in pretreated leaves • Untreated but sundried leaves retained more of the green colour in all three samples. • Untreated dried samples were used in the cooking tests.

38. Cooking pre trials Objective – determine the best way to utilise dried leaves Methods • The dried (fresh) samples of the 3 vegetables were used • stew in two forms eforiro and egusi. • A big pot of sauce was made and then divided into two – • one for fresh leaves and • the other for reconstituted dried leaves. • The dried leaves were boiled for about 5mins before adding to the sauce. • 3 vegetables (teteabalaye, ugu and igbagba) x 2 stews (egusi and eforiro) x 2 types (fresh or dried leaves) = making 12 samples. • Questionnaires were used samples were scored for sensory attributes using hedonic scale of 1-9.

39. The Ingredients

41. Observations • All the samples were delicious to taste • Dried leaves were darker in color while fresh leaves retained their green color • Dried leaves were turgid – had tough texture unlike fresh leaves that were soft • egusi masked the ability of tasters to differentiate between vegetable stews prepared with fresh or dried leaves • Thus inclusion of egusi in sauce preparation was discontinued

42. Field trials Objective – to get consumers opinion on cooked dried leaves Methods • 2 locations Ogbomoso and Akaran near Ibadan in Oyo State. • 10 panelists were used in each location. • Some panel members were literate and could understand the questionnaire but for the illiterates, members of the project team conducted the interview. • Panelists were asked to score the vegetable stews on a hedonic scale 1-9 with 9 being the best and 1 the lowest score.

43. Results – sensory evaluation

44. Tasting session

45. Dried Vs Fresh Vegetable Leaves • Panelists were able to differentiate the samples • Fresh vegetable stews scored higher marks than dried vegetable • Difference in scores was not significant • fresh samples were softer in texture and greener in colour • Some panelists could not tell the difference and said the difference was not noticeable. Conclusion • Using the right recipe (with condiments), dried vegetable leaves can be used in preparation of vegetable stew Implications - surplus vegetable leaves may be preserved by sun-drying and reconstituted for later use.

46. Product DevelopmentUIV enriched snacks • Chinchin & Cookies • Regular recipe + 0-5% dried Veg • Dried leaves ground – pestle & mortar

47. Recipes

49. Preliminary observations • Nutrient analysis – yet to be concluded • As UIV % increased- product color darkened • Taste & texture not affected • Sensory test • Younger panelists – preferred 0-2.5% • Older panelists – preferred higher %

50. Development of a dryer Features • Insulated against heat loss • Requires little charcoal • Complete drying – within 1hr • Hygienic condition • Affordable • Chimney • Mobile – on wheels • Colour retention • Minimal nutrient loss