Carissa spinarum L. is one of the wild plants that gives a fruit and it consumed by the peoples who are lived in the study areas without any knowledge of its nutrients. Thus, this research work was designed to explore the physicochemical properties and nutritional values of the Carissa spinarum L. fruits which were collected from two different geographical sites of Korem-Ofla wereda mainly Delesa and Maidokorem. The samples used for the study were randomly selected from the described sites, respectively, and the analysis of its physicochemical and nutritional values of the fruit was carried out using standard official methods. The result showed that, while the minerals, fat, energy, and titratable acidity contents were significantly different (p < 0.05) among the fruits collected from the two different geographical zones, the remaining compositions were not significantly different (P > 0.05). In conclusion, the plantations in different geographical locations were significantly affected some of the physicochemical, nutritional, and sensory properties of the fruit. It is, however, recommended that the effect of the geographical location on some nutritional and physicochemical properties of the fruit was significant, it can also develop Carissa spinarum L. based value-added food products.

Banana drying is an important process that used to extend the shelf life and increase the marketability of the dried banana. However, this process can lead to changes in weight loss, firmness, and color, which may influence consumer acceptance. As a result, it is crucial to monitor these changes to maintain the desired quality. Therefore, the aim of this study was to assess the quality of sliced bananas during the drying process by simultaneously monitoring their optical and physical properties using laser light backscatter imaging, near-infrared spectroscopy, and electrical impedance spectroscopy techniques. Banana sliced were prepared with 10 mm thickness and immersed into 4% ascorbic acid solution and water as treated and control samples dried at 50 °C for 6 h. The parameters measured were weight loss, color, firmness, NIR absorbance in the range from 740 to 1700 nm and electrical impedance in the frequency range from 30 kHz to 1 MHz. Absorption, reduced scattering and diffusion coefficients, penetration depth and full width at half maximum (FWHM) were computed on the LLBI signal at wavelengths of 532, 635, 780, 808, 850 and 1064 nm. The results showed that both the drying time and the ascorbic acid treatment and their interaction affected the measured values. The strong NIR absorption spectrum changes observed at wavelengths of 1064 and 1416 nm. The least squares partial regression model (PLSR) was performed with high accuracy for weight loss (%) and relaxation time (ms) at a coefficient of determination (R2) of 0.940 and 0.945 with a mean square error (RMSE) of 3.748 and 0.001, respectively. The electrical impedance spectral changes were found in the frequency range from 60 Hz to 1 MHz. The most sensitive laser wave lengths to evaluate optical properties were 532, 635, 780 and 1064 nm. Therefore, laser backscatter imaging together with NIR spectroscopy and impedance spectroscopy is a promising technique to assess the quality of sliced bananas during the drying process. Graphical abstract