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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.

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The safety of street foods remains a public health concern especially in developing countries like Kenya where foodborne illnesses associated with these foods have often been reported. This study determined the food hygiene and safety knowledge and practices of 345 street food vendors (SFVs) in selected locations within Kiambu County, Kenya. Data collection was accomplished through face-toface interviews using structured questionnaires and extensive observation using an assessment tool for observation of personal hygiene and food handling practices of SFVs and the condition of the vending environment. The results indicated that the majority of the SFVs were male (63.2%) with 38.1% of them having attained secondary school education. About 93% of the SFVs had not received any formal training on food hygiene and safety. Majority of SFVs handled food with bare hands (96.8%) or handled money while serving food without washing hands (86.1%). Few also practiced preservation with 78.3% storing foodstuff that required refrigeration at ambient temperatures while 22.3% stored leftovers without any form of preservation and sold them the following day. Whereas public health officers' visits were found to significantly (P<0.0001) motivate SFVs to obtain a food handler's medical certificate, only about 27% had obtained it. These findings suggest that street vended foods sold in this study area may pose a significant potential hazard to public health due to the poor hygiene and handling practices reported.

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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.

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A decline in common bean production has been ascribed to climate change. The adoption of improved beans aims to increase productivity, profitability, and consumption, thus reducing food and nutrition insecurity in the country. The aim of this study was to determine the proximate composition, antinutrient content, mineral content, and bioaccessibility of zinc and iron in two improved bean varieties grown in Kenya; Faida (biofortified) and RM 01 (drought tolerant)). The protein content of RM 01 (22.48%) was significantly higher than the Faida bean variety (20.90%). RM 01 bean variety had higher crude fat (4.20%) and crude fiber (4.31%) content compared to Faida which had 3.78% and 3.31% for crude fat and crude fiber respectively. Faida recorded significantly higher levels of iron (61.5 mg/kg) and zinc (26.8 mg/kg) content. Faida beans also had significantly (p< 0.05) high levels of phytates (11.70 mg/g) and tannins (4.39 mg CE/g). Phytate to iron ratio for Faida was 17.08 and RM 01 was 15.19 while the phytate-to-zinc ratio was 42.26 and 35.36 for Faida and RM 01 respectively. The RM 01 bean variety had iron bioaccessibility of 35% and zinc bioaccessibility of 65% compared to the Faida bean variety which had bioaccessibility of 29% and 42% for iron and zinc respectively. In conclusion, RM 01 variety is a better source of iron, zinc, and protein compared to the Faida variety.