Relationship between physicochemical and sensory properties of selected local and hybrid cooking bananas in Uganda

Abstract

The East African Highland Cooking bananas are a staple food in Uganda. In this work, the relationship between sensory characteristics and the physicochemical properties of 23 local and hybrid cooking bananas was studied. The selected cultivars included officially released hybrids (n=2), hybrids still under evaluation (n= 12), female parents used in breeding (n=3), and popular local East African Highland (EA-AAA) cooking bananas (n=6). Peel thickness, finger length, TSS, TA, dry matter, starch content including amylase & amylopectin composition, crude fat, ash, protein, texture, phenolic compounds, tannins and total flavonoids were determined using standard methods. Results of proximate composition and starch composition indicated that local cultivars Mpologoma, Mbwazirume, and Muvubo had significantly (p < 0.05) higher values of moisture, crude fat, ash, protein and amylase than hybrids. Hybrids NARITA 6 and NARITA 2 had significantly (p < 0.000 1) the highest dry matter content of 27.94 % and 28.09 %, respectively. Hybrids NA RITA 2, NA RITA 11 , l 79 I 4S- 24 and ARITA 24 had relatively higher phenolic compounds than most of the local cultivars. To examine the eating quality characteristics, the traditional steam and mash method was used. Thirteen trained panellists were used to assess sensory characteristics of the cooked bananas. The main sensory characteristics of cooked bananas according to panellists were; a homogeneous yellow colour, moist smooth and soft texture, an aroma of bananas in leaves, a mild sweet taste and low astringency. Sourness, high astringency, pale yellow, blackish & mottled colours, extreme firmness and too soft texture were described as undesirable characteristics. Some hybrid cultivars (N2 1, N15, NI 1, N8, 17914S-24, N2 and N6) had significantly (p < 0.05) lower scores for sensory characteristics than the local bananas. However, the sensory scores of other hybrids such as M32, ARITA 17, M9, M33 and NARITA 24 were not significantly different from those of local cultivars. According to the PCA, flavonoids and ash content are correlated with astringency (r = 0.014, r = -0.006), stickiness (r =0.3 10, r = 0.402), mouldability (r = 0. 12 1, r = 0.226) & smoothness (r = 0.130, r = 0.295) of hybrids N8, N2 l, & 179 I 4S-24. Total tannins and amylopectin content determine the moistness (r = 0.454, r = 0. 193) of cooked bananas as observed in Nakitembe, M32, and Enzirabahima. Sourness is correlated with total phenols (r = 0.453) content in hybrids 11, NI5. The large finger circumference is explained by the high dry matter and high amylase content (r = -0.064, r = 0.090) in NI I & Nl5. Firmness and hardness are explained by high search (r =0.244, r = 0.282) content mainly in hybrids N2, N6, M9 & M33 and a local cultivar Yfuuka. High starch content was associated (r = 0.453) with a firm and hard texture while Matooke taste is correlated with high titratable acidity (r = 0.404) while sweetness & a yellow colour and homogeneous colour are associated with TSS (r = 0.405, r = 0.581, r = 0.578) in Kibuzi, Nakitembe, Nakawere, Muvubo, Enzirabahima, Kabucuragye, M32, N 14, N24 and N 17. Therefore, these quality properties could be used by breeders as parameters for screening clones for food quality to meet consumer expectations.