Effect of Optimal Incorporation of Hybrid Banana Flours on Acceptability of Soy Fortified Banana Flour Based Products

Full Length Research Paper

Effect of optimal incorporation of hybrid banana flours on acceptability of soy fortified banana flour based products

Florence I. Muranga 1,2 *, F. Nabugoomu 3 and J. G. Katebarirwe 4

1Department of Food Science and Technology, Makerere University, P.O Box 7062, Kampala, Uganda. 2Presidential Initiative on Banana Industrial Development (PIBID), P.O Box 32747, Kampala, Uganda. 3Faculty of Science and Technology, Uganda Christian University, P.O Box 4 Mukono, Uganda. 4Department of Food Processing Technology and Home Economics, Kyambogo University, P.O. Box 1, Kampala, Uganda.

Accepted 25 November, 2011

The cooking banana (matooke) was identified as a target food crop for development in Uganda amidst high levels of malnutrition and food surpluses in the country. The aim of this study was to optimize incorporation of soy into raw, instant and extruded hybrid matooke (Tooke ) flour for making soup and porridge in order to supplement the cooking banana as a raw material for the food industry. Raw, instant and extruded Tooke flours (RTF, ITF and ETF respectively) fortified with soy were substituted with correspondingly processed hybrid banana flour (HB) at seven levels for preparation of soups and porridges as indicative products, and their acceptability was determined to establish the optimal ratios of HB substitution. A quadratic surface response model was used to determine optimal HB levels based on consumer acceptability of the soups and porridges produced. The findings indicate that optimal ratios for HB varied with processing technique and product type. The optimal HB levels were 19.3, 28.8 and 8.2% for RTF, ITF and ETF soy-fortified porridges, respectively and 7.6% for ITF soy-fortified soup. Extrusion cooking was reported as the more appropriate technology for HB incorporation into soy- fortified Tooke based porridges because it allowed the highest level of substitution with HB. Further, the porridges were more acceptable as compared to the soups; hence the above ratios could be adopted for use in making children’s porridges incorporating HTF.

Key words: Extrusion cooking, porridge, soup, matooke, acceptability.

INTRODUCTION

Uganda is the largest producer of bananas and plantains grown by 72% of farmers on an average plot size of one in sub-Saharan Africa and also has the highest per capita hectare (Karugaba and Kimaru, 1999). consumption in the world with a consumption rate of 191 However, ‘matooke’ farmers suffer high postharvest kg per year (IITA, 2009). The estimated production losses especially during peak harvest periods due to the stands at 9.5 million tones, which is 26.4 and 36% of the fact that ‘matooke’ is highly perishable. Currently, world’s and Africa’s total production, respectively numerous technologies have been explored to add value (FAOSTAT, 2009). Cooking bananas also known as to ‘matooke’, thereby increasing its shelf life. ‘Matooke’ is ‘matooke’ (East African highland cooking bananas) are also susceptible to disease (Tushemereirwe, 1996), and host plant resistance has long been identified as the most feasible and sustainable intervention for pests and diseases (Ssali et al., 2010). Through breeding and *Corresponding author. E-mail: [email protected]. Tel: selection, the Foundation Hondurena de Investigation +256772363271, +256312265789, +256414371050. Fax: Agriola (FHIA) and International Institute of Tropical +256414340413. Agriculture (IITA) introduced hybrid/exotic banana geno- Muranga et al. 19789

types that have promising disease resistance and soups and 18.2, 17.8 and 6.9% for RTF, ITF and ETF, respectively agronomic performance with respect to Black sigatoka, for the porridges. However, the Hybrid Tooke flour proportions were Fusarium wilt and yield (Tushemereirwe, 1996; varied from low (0%) to high (>80%) for both the soups and porridges. The designs for the soups and porridges are as shown in Tushemereirwe et al., 1999; Nowakunda, 2000). Tables 1 and 2. The soups were formulated following the recipe The postharvest characteristics and qualities of some reported by Natiko (2001). The ingredients were weighed of these new banana cultivars (FHIA 01, FHIA 17 and separately on a top balance (Sartorius, BA2100s, Germany) and a FHIA 23) with respect to end users’ preference in terms measured amount of water was added. When the soups started of cooking and sensory qualities in comparison to the boiling, the heat was reduced, the pan was partially covered and the soups simmered until cooked (5 min). Porridges were prepared most commonly liked land race cooking banana cultivars by mixing a measured amount of flour from each of the blends with (Mbwazirume and Kisansa) have been documented as cold water (¼ L) before finally adding it to boiling water (3/4 L) and fairly acceptable (Nowakunda, 2000). Although, they boiling continued for 5 min. Four tablespoonfuls of sugar were have not been totally accepted as traditional foods, the added to one litre of the ready porridges. hybrid varieties are capable of producing high flour yield due to the big bunch sizes, and could therefore find use Sensory evaluation in the virgin banana flour industry. Recent advances in ‘matooke’ processing have led to This was done using a trained panel of seven judges to assess how reduction in the relative bulk of ‘matooke’ resulting in the different treatments affected consumer quality attributes of the banana flours branded ‘Tooke’, giving rise to Raw ‘Tooke’ various products. The panelists were asked to make a comparative flour (RTF), instant ‘Tooke’ flour (ITF) and Extruded rating of the different soups/porridges using a nine-point hedonic ‘Tooke’ flour (ETF) (Muranga, 1998) (unpublished). Opti- scale with six indicator parameters namely colour, taste, flavour, mouth feel, consistency and overall acceptability. The soups/ mal levels for incorporation of soy in ‘Tooke’ flours have porridges were presented to them in a balanced incomplete block been established with respect to both physicochemical design adopted from Cochran and Cox (1957), with an efficiency and sensory parameters giving rise to products with good factor of 88%. In this design, each individual panelist constituted an consumer attributes, high energy and protein efficiency incomplete block, making a total of seven blocks. The number of ratio (PER) due to the former high energy density and the units per block or block size (k) was limited to four so as to ease panelist ability to reach satisfactory rating. Seven levels of hybrid latter good lysine content (Katebarirwe, 2005) Tooke flour, each replicated four times were tested for each (unpublished). However, this has not been done for the product. HB flour, which is important to avoid bias towards the ‘Tooke’ based products, particularly due to the higher astringency reported in the hybrid banana varieties. The Optimization objective of this study therefore was to establish whether incorporation of hybrid matooke flours in the matooke/soy The optimum ratios of incorporating RHTF, IHTF and IHTF into mixtures causes a significant effect on consumer RTF, ITF and ETF, respectively in the soups and porridges were established with respect to consumer acceptability by fitting a acceptability. Soup and porridge were used as indicator quadratic response surface model, yij = µ + βj + ρ1xi + ρ2xi2 + eij, products to optimize the level of hybrid matooke to the data from sensory experiments, where µ = constant term, βj = incorporation into the products in a bid to address the effect of the jth panelist, xi is the ith (hybrid banana ratio) treatment sustainability of banana processing. and ρ1 and ρ2 are regression coefficients and eij is an error term. This can be extrapolated as shown in Figure 1.

METHODS RESULTS Preparation of matooke flours Sensory characteristics of the soups RTF, ITF and ETF were prepared according to patent numbers AP/P/2005/003308, UG/P/04/00010 and UG/P/04/00011, respec- Six indicator parameters namely colour, taste, flavor, tively as reported by Muranga et al. (2009). The hybrid flours were mouth feel, consistency and overall acceptability were also similarly processed to give raw hybrid Tooke flour (RHTF), instant hybrid Tooke flour (IHTF) and extruded hybrid Tooke flour analyzed. Substitution of Tooke flours with HTF (EHTF). significantly (P<0.001) reduced colour preference scores in all the soups. The best preferred colours were those of the Tooke flour based soups (Plates 1 and 2). The Preparation of the test products decrease in preference scores could be a result of impartation of dark brown colours into the soups by the The test products were prepared by substituting a percentage of HTF. The scores followed the trend: RTF>ITF>ETF, RTF, ITF and ETF with RHTF, IHTF and IHTF, respectively and which was in line with increased colour darkening thus fortifying the flours with soybean flour at seven levels. The research showing preference for soups with lighter colours. design was such that the ratios for Tooke flours: hybrid Tooke flour: soybean flour was added to one unit. The optimal soy levels from Substitution of Tooke flours with HTF generally lowered Katebarirwe (2005) (unpublished) were adopted. They were fixed at the taste preference scores for all the soups, with soups 11.6, 20.7 and 19.5% for RTF, ITF and ETF, respectively for the based on pure Tooke flours (0% HTF) having the most 19790 Afr. J. Biotechnol.

Table 1. Design for incorporation of HTF and soybean into Tooke flour based soups.

Tooke Flour (T) (%) Hybrid Tooke Flour (H) (%) Soybean Code RTF ITF ETF RHTF IHTF EHTF (So) (%) S1-RTRHSo 88.4 - - 0 - - 11.6 S1-ITIHSo - 79.3 - - 0 - 20.7 S1-ETEHSo - - 80.5 - - 0 19.5 S2-RTRHSo S2- 76.8 - - 11.6 - - 11.6 ITIHSo - 60.3 - - 19.0 - 20.7 S2-ETEHSo - - 64.4 - - 16.1 19.5 S3-RTRHSo 61.8 - - 26.6 - - 11.6 S3-ITIHSo - 59.0 - - 20.3% - 20.7 S3-ETEHSo - - 56.3 - - 24.2 19.5 S4-RTRHSo 58.2 - - 30.2 - - 11.6 S4-ITIHSo - 39.7 - - 39.6 - 20.7 S4-ETEHSo - - 48.3 - - 32.2 19.5 S5-RTRHSo 44.2 - - 44.2 - - 11.6 S5-ITIHSo - 20.7 - - 58.6 - 20.7 S5-ETEHSo - - 24.2 - - 56.3 19.5 S6-RTRHSo 11.6 - - 76.8 - - 11.6 S6-ITIHSo - 19.0 - - 60.3 - 20.7 S6-ETEHSo - - 16.1 - - 64.4 19.5 S7-RTRHSo 0 - - 88.4 - - 11.6 S7-ITIHSo - 0 - - 79.3 - 20.7 S7-ETEHSo - - 0 - - 80.5 19.5

S-RTRHSo, Raw Tooke flour-based soups; S-ITIHSo, instant Tooke flour-based soups; S-ETEHSo, extruded Tooke flour- based soups. 1 to 7, Levels of incorporation.

preferred tastes. The flavour scores did not follow a clear all the evaluated sensory attributes. Generally, the soups pattern though, to some degree, they lowered as the based on RTF were the most acceptable and those levels of HTF increased, particularly in the ITF and ETF based on ETF were the least acceptable. based soups. The soup incorporating 76.8% RTF had the most preferred flavor among the RTF based soups, whereas the soups incorporating 0% ITF and ETF had Sensory characteristics of the porridges the most preferred flavors. The unclear pattern followed by flavour preference scores could be explained by effect Six indicator parameters namely colour, taste, flavor, of other ingredients that were added in the soups in mouthfeel, consistency and overall acceptability were similar quantities. The panelists could have preferred analyzed. The colour preference scores increased up to flavors of these ingredients to different degrees. The 26.6% HTF substitution level and then decreased preference scores for both taste and flavour followed the thereafter but not significantly in the RTF based trend: ITF>ETF>RTF (Table 3). porridges. Increased substitution with HTF on the other Preference scores for mouth feel were higher in pure hand, led to a general decrease in colour preference Tooke flour-based soups and substitution with HTF led to scores for ITF and ETF based porridges. The most a general decrease in the scores in all soups with preferred colour was that of porridges incorporating exception of the soup incorporating 19% IHTF. On the 24.8% of RHTF and 0% of both IHTF and EHTF. The contrary, there was an increase in the preference scores IHTF and EHTF both imparted a dark brown colour into for consistency with increased substitution, with HTF up the porridges (Plates 3 and 4), which could have lowered to 19% IHTF and EHTF up to 24.2%. The scores for colour preference. soups based on RTF did not follow a clear pattern but the The preference scores for taste and flavor increased soup incorporating 88.4% RTF had the most preferred with increased substitution of Tooke flours with HTF up to consistency. The overall acceptability scores generally 31.4% HTF and 17.8% HTF for RTF and ITF based decreased with increased substitution with HTF. The pure porridges, respectively, but decreased thereafter. Gene- Tooke flour-based soups were more acceptable because rally, addition of HTF into ETF based porridges led to a they were superior to those incorporating HTF in almost decrease in taste and flavor preference scores, with pure Muranga et al. 19791

Table 2. Design for incorporation of HTF and soybean into Tooke flour based porridges.

Tooke flour (T) (%) Hybrid Tooke flour (H) (%) Soybean (So) Code RTF ITF ETF RHTF IHTF EHTF (%) P1-RTRHSo 81.8 - - 0 - - 18.2 P1-ITIHSo - 82.2 - - 0 - 17.8 P1-ETEHSo - - 93.1 - - 0 6.9 P2-RTRHSo 63.6 - - 18.2 - - 18.2 P2-ITIHSo - 64.4 - - 17.8 - 17.8 P2-ETEHSo - - 86.2 - - 6.9 6.9 P3-RTRHSo 57.0 - - 24.8 - - 18.2 P3-ITIHSo - 52.3 - - 29.0 - 17.8 P3-ETEHSo - - 66.4 - - 26.7 6.9 P4-RTRHSo 40.9 - - 31.4 - - 18.2 P4-ITIHSo - 41.1 - - 41.1 - 17.8 P4-ETEHSo - - 46.6 - - 46.5 6.9 P5-RTRHSo 29.6 - - 52.2 - - 18.2 P5-ITIHSo - 29.5 - - 52.7 - 17.8 P5-ETEHSo - - 26.8 - - 66.3 6.9 P6-RTRHSo P6- 18.2 - - 63.6 - - 18.2 ITIHSo - 17.8 - - 64.4 - 17.8 P6- ETEHSo - - 6.9 - - 86.2 6.9 P7-RTRHSo 0 - - 81.8 - - 18.2 P7-ITIHSo - 0 - - 82.2 - 17.8 P7-ETEHSo - - 0 - - 93.1 6.9

P-RTRHSo, Raw Tooke flour-based poridges; P-ITIHSo, instant Tooke flour-based porridges; P-ETEHSo, extruded Tooke flour-based poridges. 1 to 7, Levels of incorporation.

10 A

Overall acceptability Overall 5

4 Observed B 3 Quadratic -.2 0.0 .2 .4 .6 .8 1.0 -0.2 0.2 0. 4 0. 6 0. 8 Reference line

Proportion of Hybrid banana flour

Figure 1. Relationship between overall acceptability and hybrid banana ratio. 19792 Afr. J. Biotechnol.

Plate 1. Soy fortified extruded banana flour-based soup.

Plate 2. Soy fortified extruded hybrid banana flour- based soup.

ETF giving porridge the most preferred taste and flavor. The preference scores mouthfeel for consistency did not Addition of HTF generally improved mouth feel but follow a clear pattern for ITF and ETF based porridges decreased consistency preference scores in RTF based but the most preferred consistency among the ITF and porridges, with porridges incorporating 18.2% HTF and ETF based porridges were at 17.8% HTF and 86.2% HTF 0% HTF having the most preferred mouthfeel and levels, respectively. Substitution of Tooke flours with consistency, respectively. The mouthfeel scores hybrid Tooke flours generally decreased acceptability of decreased in ITF and ETF based porridges with Tooke-soy based porridges. The acceptability scores increased addition of HTF (Table 4). followed the trend RTF>ITF>ETF. The most acceptable Muranga et al. 19793

Table 3. Mean scores for sensory characteristics of ITF soups incorporating HTF and soybean*.

HTF Colour Taste Flavour Mouth feel Consistency Overall acceptability content RTF ITF ETF RTF ITF ETF RTF ITF ETF RTF ITF ETF RTF ITF ETF RTF ITF ETF 1 8.0 7.4 7.6 6.3 7.0 7.0 5.7 7.3 6.1 6.6 6.4 6.5 5.1 6.3 6.5 7.7 7.1 7.3 2 6.5 7.2 5.1 6.1 5.6 5.4 5.3 6.3 5.2 6.0 7.1 5.7 5.6 6.8 6.8 7.3 6.9 6.3 3 6.1 6.8 5.2 6.0 6.3 4.9 6.0 6.2 5.9 5.9 6.1 5.8 5.7 5.9 6.9 6.9 6.9 6.5 4 6.2 5.6 3.8 5.6 5.7 4.7 5.5 6.0 4.6 5.8 6.1 5.5 5.1 5.7 5.5 6.6 6.3 5.5 5 4.8 5.8 3.4 5.7 5.6 4.8 5.5 6.2 4.0 5.9 5.3 5.3 6.4 5.2 6.4 5.6 6.0 4.4 6 4.3 5.0 2.8 5.3 6.7 4.7 6.5 6.1 3.8 4.8 5.6 5.8 6.3 5.4 5.0 5.7 6.4 3.5 7 3.9 4.1 1.9 5.1 5.0 3.9 5.7 5.8 4.4 4.8 4.4 4.8 7.1 5.3 3.3 5.4 4.7 2.8 S.e.d 0.805 0.906 0.861 1.056 0.742 0.898 1.312 0.805 1.469 0.736 0.947 1.024 1.143 0.951 1.196 0.799 0.627 0.585

RTF : Raw ‘Tooke’ Flour based soups; ITF : Instant ‘Tooke’ Flour based soups ; ETF : Extruded ‘Tooke’ Flour based soups; HTF : Hybrid Tooke Flour (Content 1 to 7 corresponding with levels of incorporation in Table 1) . *The values are means of scores from four panelists. They are based on a 9-point hedonic scale (1 = Dislike extremely, 9 = like extremely).

porridges overall were those incorporating 31.4, based porridges, respectively. Results from the reported that a high tannin content negatively 17.8 and 0% of RHTF, IHTF and EHTF, respec- sensory experiment indicate that there is a affected appearance of the cooked hybrid bana- tively. The porridges were generally superior in significant relationship between the HTF ratio and nas. The overall acceptability scores generally the other sensory attributes though more so in the overall acceptability of the RTF based porridges at decreased with increased substitution with HTF. taste attribute. p = 0.053. The variation in overall acceptability is The pure Tooke flour-based soups were more represented by 20.9% of the HTF ratio. The acceptable because they were superior to those regression analysis indicates that overall accept- incorporating HTF in almost all the evaluated Optimization ability is quadratically related to HTF ratio and has sensory attributes. Generally, the soups based on the following equation: RTF were the most acceptable and those based It was not possible to determine optimum ratios of on ETF were the least acceptable. These results HTF in the raw and extruded Tooke flour-based Y = 7.0069 + 1.0755X - 3.5619X2 reveal that high levels of substitution with HTF soups by fitting a quadratic response surface resulted in inferior soups, which is in conformity equation to the data from the soup sensory with earlier reports that the hybrid bananas are experiment. The regression analysis indicated that DISCUSSION inferior to landrace cultivars with respect to use overall acceptability of the soups is not quadra- quality (Semwanga and Thompson, 1994; tically related to the HTF ratio. As such, a Sensory characteristics of the soups Nowakunda, 2000). quadratic response surface model could not be fitted on the data from the sensory experiment. The general decrease in preference scores for This was probably because the preference scores colour, taste mouth feel and overall acceptability Sensory characteristics of the porridges given by the different panelists for overall when the Tooke flours were substituted with HTF acceptability did not follow a clear pattern. particularly at high levels could be attributed to the The porridges were generally superior in the other The optimum ratio of HTF in ITF based soup high tannin content in the latter flours sensory attributes though more so in the taste was 0.076 (7.6%). The data from the porridge (Nowakunda, 2000). In fact, some panelists attribute. According to Semwanga and Thompson sensory experiment gave 0.193 (19.3%), 0.288 complained of a puckering sensation in the mouth (1994), taste significantly influences acceptability. (28.8%) and 0.782 (78.2%) as optimum ratios of caused by tasting soups incorporating high levels The decrease in overall acceptability was in line HTF in raw, instant and extruded Tooke flour- of HTF (above 55%). Nowakunda (2000) further with the general decrease in preference scores for 19794 Afr. J. Biotechnol.

Plate 3. Soy fortified extruded banana flour-based porridge.

Plate 4. Soy fortified extruded hybrid banana flour-based porridge.

all the above attributes, when the landrace banana flours negatively affect appearance, taste, flavor and mouthfeel were substituted with HB flours particularly at high levels (Nowakunda, 2000). Therefore, the final judgments of (above 50%). This could be attributed to the high tannin panelists summing up all the perceptions indicated that content in the latter flours, which has been reported to substitution of landrace banana flours with high levels of Muranga et al. 19795

Table 4. Mean scores for sensory characteristics of ITF porridges incorporating HTF and soybean*.

HB Colour Taste Flavour Mouth feel Consistency Overall acceptability content RB PB EB RB PB EB RB PB EB RB PB EB RB PB EB RB PB EB 1 6.8 6.8 7.4 5.6 7.5 7.2 6.1 6.6 6.6 6.2 7.2 7.7 7.5 7.0 6.8 7.3 7.0 7.8 2 6.9 6.8 7.1 5.7 8.0 7.0 6.1 6.8 6.4 6.4 7.3 6.8 6.8 8.2 6.8 7.0 7.3 6.8 3 7.0 6.5 5.5 6.4 7.5 6.8 6.7 6.0 6.3 6.2 6.5 6.8 6.9 6.3 6.5 7.0 6.8 6.3 4 6.6 6.5 5.0 7.4 7.0 6.9 6.7 6.1 6.5 6.9 6.4 6.5 5.9 6.0 6.3 7.5 6.8 6.0 5 6.1 6.5 4.0 7.0 7.0 6.8 6.3 6.1 6.5 6.9 6.9 6.5 5.7 7.7 6.3 7.3 7.0 6.0 6 6.1 6.3 4.1 5.6 6.2 7.0 6.5 6.1 6.6 7.0 5.6 6.5 5.7 6.8 7.0 6.3 6.0 6.0 7 5.3 5.5 3.8 5.7 5.0 6.9 6.2 3.6 6.4 6.9 5.5 5.3 5.0 6.8 6.3 5.7 5.5 5.7 S.e.d 0.943 1.057 0.927 1.168 0.729 0.656 0.703 0.593 0.707 0.700 0.906 0.639 0.740 0.756 0.696 0.707 0.845 0.510

B, Raw banana flour based porridges; PB, pregelatinised banana flour based porridges; EB, extruded banana flour based porridges; HB, hybrid banana flour. *The values are means of scores from four panelists. They are based on a 9-point hedonic scale (1 = Dislike extremely, 9 = like extremely).

HB flours resulted in inferior porridges. Award of the Rockefeller Foundation. Special Muranga FI, Kanyago M, Nabugoomu F, Ntambi JM (2009) thanks also, go to the BAGKF-Detmold Germany Investigation of the potential of fortified Instant Matooke Flour (ITF) in rehabilitation of malnourished children (Part for the extrusion cooking of the matooke. We 1). Optimal level of fortification of instant tooke flour porridge Conclusion acknowledge the Presi-dential Initiative on and its nutritional quality attributes. AJFS, 3(10): 273-278. Banana Industrial Develop-ment (PIBID) for Natiko GJ (2001). Investigation of the Potential of Banana Incorporation of hybrid Tooke flour had a providing the final infrastructure for writing and Flours as a Carbohydrate base in Soup Making. Unpublished Special Project Report, Dept. of Food Science significant impact (P<0.001) on the consumer publication of this work. & Technology, Makerere University Kampala. pp. 1-4, 15- acceptability of the Tooke-based soups and 31. porridges. The products incorporating hybrid Nowakunda K (2000). Determination of Consumer Tooke flours were less acceptable than those REFERENCES Acceptability of Introduced Bananas. Unpublished Msc. Thesis, Dept. of Crop Science, Makerere University based on pure Tooke flours. Although hybrid Cochran WG, Cox GM (1957). Experimental Designs. 2nd ed. Kampala. pp. 1-44. Tooke flour finds better application in porridges John Wiley and Sons, Inc. New York. pp 148-181. Ssali RT, Nowankunda BEK, Batte M, Tushemereirwe WK than soups, they are inferior to the landrace FAOSTAT (2009). Crop production. www.faostat.fao.org (2010). On-Rarm partipatroty evaluation of East African ‘matooke’. This implies that effort should be made Accessed on 9 November 2011 Highland Banana ‘matooke’ hybrids (Musa spp). Proc. International conference on bababa and plantain in Africa. in improving management to boost ‘matooke’ IITA (2009). Banana and plantain. www.iita.org/banana-and- plantain Accessed on 9 November 2011. Eds: Dubois et al Acta Hortic. 879: 585-592 production and prevent diseases. Any effort to Karugaba A, Kimaru G (1999). Banana production in Uganda. Semwanga JK, Thompson AK (1994). Investigation of boost production through genetic engineering An essential food and cash crop. RELMA technical postharvest and eating qualities likely to influence should ensure that the sensory aspects of the handbook no. 18. Regional land management unit, acceptability of matooke banana cultivares to be introduced in Uganda. Aspects Appl. Biol. 39: 207-213. landrace ‘matooke’ varieties are maintained if the RELMA/SIDA, ICRAF house, Gigiri P. O. Box 63403, Nairobi, Kenya, pp. 1-2. Tushemereirwe WK (1996). Factors influencing the leafspot new varieties are to be acceptable to the Katebarirwe JG (2005). Determination of optimum ratios of diseases of highland bananas in Uganda. A PhD Thesis consumers. incorporation of soybean into banana based weaning foods. submitted to the University of Reading, UK. Unpublished Msc. Dissertation, Makerere University, Tushemereirwe WK, Kangire J, Nowakunda K (1999). Fusarium wilt resistant bananas considered appropriate Kampala, Uganda. pp. 68-90. Muranga FI (1998). Composition and Physicochemical replacements for cultivars susceptible to the disease in ACKNOWLEDGEMENTS characteristics of Starches of different banana varieties. Uganda. Uganda J. Agric. Sci. 5: 62-64. Unpublished PhD Thesis submitted to Makerere University This research was possible through funding by Kampala, Dept of Biochemistry, Faculty of Science, Makerere University through the African Career Uganda.