2.3. Preparation and Application of Coating Formulation

Two different coating application methods were tested to determine the most effective mode of application to be used on the cassava roots. Coating was performed on the same day that the cassava roots were harvested. The differently treated roots were then subjected to physical, physiological, and chemical analysis for the entire storage duration at two-day intervals.

The coating formulations used were 1.5% xanthan gum, 1.5% xanthan/guar gum, and 2% xanthan/guar gum. The 1.5% xanthan gum was prepared by dispensing 1.5 g of xanthan gum into 100 ml of distilled water. This was heated at 40°C on a magnetic stirrer for one hour. The 1.5% xanthan/guar gum solution was prepared by dispensing 0.75 grams of xanthan gum and 0.75 grams of guar gum into 100 ml of distilled water while the 2% xanthan guar gum solution was prepared by dispensing 1 gram of both xanthan gum and guar gum into 100 ml of distilled water and heated at 60°C on a magnetic stirrer for one hour. Coating was done on the same day that the roots were harvested. For the dipping method of application, the already cleaned roots were immersed into a bucket containing the coating solution. The roots were let to stay in the solution for three minutes after which they were removed and excess solution was left to drip off the cassava for one minute. The roots were then placed in clean plastic crates and left to dry after which they were stored for the twenty day storage duration. For the spraying technique, the solution was put in a hand held sprayer and this was then dispersed onto the cleaned roots as demonstrated by Pérez-Gallardo et al. [15]. The roots were then placed in clean crates for air drying as recorded by Dhall [14]. This was done in the open air. Drying took 12 hours. Storage was done at 25°C. Cassava roots under the different treatments were then tested for the twenty days storage duration at two-day intervals to determine the effect of the coatings on the physical, physiological, and chemical properties of the cassava roots.