Nutritional Composition of White and Reddish-Orange Guava (Psidium guajava) L. Varieties Growing in Homa Bay County, Kenya

Abstract

Guavas in Kenya are mainly consumed at the household level. However, limited research and development are aimed at domesticating and commercializing the fruit. This has hindered the country's establishment and improvement of structured guava value chains. A nutritional assessment of guava varieties (white and reddish-orange) growing wild in Homa Bay County was done to explore their utilization potential. Stratified simple random sampling and standard nutrient assessment procedures were adopted. The samples were analyzed for moisture content, proximate composition, minerals, vitamin content, and calorific value based on standard procedures. The moisture content of the white variety was significantly higher than the reddish-orange variety at 84.60%±0.55 and 80.32%±1.61 respectively. However, the crude fibre in the reddish-orange variety was significantly higher than the white variety at 6.02%±0.11 and 3.49%±0.42 respectively. There was no significant difference in the ash content for the reddish-orange variety at 3.50%±0.15 and the white variety at 3.88%±0.29, as well as in protein (p=0.06) at 1.37%±0.19 and 1.84%±0.26, respectively, and fat content at 0.89%±0.07 and 1.16%±0.20, respectively. There was no significant difference in Vitamin C content in the white variety at 16.03±0.92mg/100g and reddish-orange at 9.3±0.00mg/100g, as well as in Niacin content in the reddish-orange variety at 3.63±0.03mg/100g and the white variety at 0.54±0.01mg/100g. The reddish-orange variety had significantly higher iron, potassium, and aluminium contents than the white variety, whereas there was no significant difference in their Sodium, lead, zinc, copper, and calcium contents. There was no significant difference in mean calorific values of the reddish-orange variety at 17.22±0.08 KJ/gram and the white variety at 16.88±0.31 KJ/gram. Considering the findings, the guavas can provide additional nutrients to households as well as the opportunity for exploitation in product development for income generation, thereby providing a means of preservation when the fruits are in season.