Protein-Energy Malnutrition (PEM) and micronutrient deficiencies are currently the most important nutritional problem in most countries. The use of mushroom flours is limited due to limited knowledge about their functional and their interactions. Nutritional and functional properties of mushroom (Agaricus bisporus and Pleurotus ostreatus) flours and their blends with maize flour were investigated using standard analytical techniques and Pearson correlations. In this study, maize flour was replaced with mushroom flours at different levels; a control sample (0%), 10%, 20%, 30%, 40% and 50% of mushroom flour. Protein content of maize flour increased with increased mushroom flour content from 6.9% to 15.87 % (A. bisporus) up to 19.32% (P. ostreatus). The mineral content increased from 2.84 -8.74mg/100g and 3.13 -5.41 mg/100g for iron and zinc in the composite flours. A significant increase in fiber (0.53-5.89%) and Ash (1.33-6.59%) was observed. Fat, moisture, carbohydrates and energy did not increase. It was observed a positive significant linear effect (p≤0.05) in the composite flours on foaming capacity, foam stability, fat absorption capacity, water retention capacity, water absorption capacity, solubility index and swelling capacity and a negative linear effect on compact density, bulk density and syneresis was found. Gelation capacity, emulsifying activity and emulsions stability of the maize flour in blend were not affected with adding P. ostreatus, while a slight decrease was observed with adding A. bisporus. These results suggested that these nutrient rich mushroom flours under investigation could serve as useful protein supplements and food fortification.

This study evaluated the effects of pretreatments (blanching (60 and 95 °C) and boiling) and drying methods (freeze-drying and oven drying) on the quality characteristics of potato flour derived from three potato varieties, namely, Shangi, Unica, and Dutch Robjin. The percentage flour yield, color, particle size distribution, flow characteristics, microstructural and functional properties of the potato flour were determined. Unica recorded the least peeling loss, while the Dutch Robjin variety had the highest. Color parameters were significantly affected (p < 0.05) by the pretreatments and drying methods. Freeze drying produced lighter potato flour (L* = 92.86) compared to the other methods. Boiling and blanching at 95 °C followed by oven drying recorded a low angle of repose and compressibility index, indicating better flow characteristics. The smallest particle size (56.5 µm) was recorded for the freeze-drying treatment, while boiling followed by oven drying had the largest particle size (307.5 µm). Microstructural results indicate that boiling and blanching at 95 °C, followed by oven drying resulted in damaged starch granules, while freeze-drying and low-temperature blanching (60 °C) maintained the native starch granule. Particle size and the solubility index of potato flour showed strong positive correlation. This study revealed that the pretreatments and drying methods affected potato flour’s physical and microstructural parameters differently, resulting in changes in their functionality.

Long-term use of fresh potatoes is constrained due to post-harvest losses and limited or poor storage systems. Loss of potato quality during storage is mostly due to weight loss, excessive sprouting, decaying, greening, pest attack and changes in sugar content which is a major concern for processors. The storability of three potato varieties namely Shangi, Unica, and Dutch Robijn was evaluated under four storage conditions: (1) room temperature (RT) (21.7 ± 5 °C) and ambient relative humidity (RH) (73.5 ± 6.7%); (2) 10 °C/75% RH; (3) 10 °C/ambient RH and (4) 7 °C/75% RH for 3 months. Parameters analysed included weight loss, sprouting, greening, rotting incidence and changes in simple sugars (sucrose, glucose and fructose) content. Shangi variety had the poorest storability having exhibited the highest weight loss, sprouting, greening and rotting rates among the varieties and in all storage conditions. In all the varieties, weight loss was highest at room temperature/RH (6.9–35.13%) and lowest at 7 °C/75% RH (1.6–3.7%). Sprouting rate was highest at RT/RH (100%) and lowest at 7 °C/75% RH (2.0–45.2%). Greening incidence was highest at RT/RH (10.3–24.0%) and lowest at 7 °C/75% RH (2.0–16.1%). The tubers accumulated simple sugars during storage with the highest relative accumulation recorded at 7 °C/75% RH. Total reducing sugars increased by 3.8–9.3-fold at RT/RH to 26.0–68.5-fold at 7 °C/75% RH. Low-temperature storage minimized the rate of physical tuber deterioration with 7 °C/75% RH best preserving the potatoes’ physical properties while it led to the highest accumulation of simple sugars.