Rastrineobola argentea common name Omena and Stolephorus delicatulus common name Kimarawali are fishes that live in the freshwater and marine waters, respectively. Both are small in size, move in schools and are landed in large numbers during their peak landing seasons. Both go by the name Dagaa or sardines. In this study, they were dried in a locally fabricated solar tunnel dryer and on a drying rack in Gazi, South coast of Kenya for 14 hrs and their drying characteristics were evaluated using drying curves. Organoleptic analysis was carried out to compare some attributes of unsalted rack dried with salted spiced solar dried Kimarawali. The final moisture content of unsalted tunnel dried Kimarawali, unsalted rack dried Kimarwali, unsalted rack dried Omena and unsalted solar dried Omena was 0.161 kg/kg dry basis (db) (13.9% wet basis: wb), 0.163 kg/kg db (14.0% wb), 0.137 kg/kg db (12.7% wb) and 0.145 kg/kg db (12.1 wb)% respectively after 14 hrs of drying. The fish in the solar dryer attained moisture levels of 15% suitable for prevention of mould growth in 8 hours. The drying rate constants for unsalted tunnel dried and rack dried Omena were 0.23 and 0.22 with coefficient of determination (R 2) values of 0.899 and 0.940, respectively. The corresponding drying rate constants for Kimarawali were 0.18 and 0.21 with coefficient of determination (R 2) values of 0.814 and 0.932 respectively. There were no significant differences in drying rate after 14 hrs of drying for the two types of fishes and drying methods. The mean drying temperature for the tunnel dryer and drying rack during the 14 hrs of drying were 40.2±9.42 and 32.1±2.71 o Celsius respectively. The corresponding relative humidity values were 53.7%±20.34 and 70.08%±2.72, respectively. There was no significant difference in the quality attributes between the tunnel and rack dried fishes. The score for overall acceptability was however higher for the spiced tunnel dried Kimarawali.

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Freshwater catfish (Clarias gariepinus) and marine catfish (Galeichthys feliceps) were smoked using Acacia raddiana (Moriela), Prosopis julifora ("Mathenge"), Azadirachta indica (Neem) and Cocos nucifera (Coconut husks) in view to assess and compare the organoleptic scores-taste, appearance and overall acceptability of the smoked fish. Insect and mould attack was also monitored during storage. The scores for taste for marine catfish were better than that for freshwater catfish irrespective of the plant materials used. Taste for freshwater catfish and marine catfish smoked with Acacia was significantly different (p<0.05). Appearance and overall acceptability for freshwater catfish smoked with Acacia, Prosopis (Mathenge), Neem, and Coconut husks was better than marine catfish though not significantly different (p<0.05). The scores for taste, appearance and overall acceptability for marine catfish smoked with Acacia, Prosopis, Neem and Coconut husks were not significantly different (p<0.05). Acacia had better taste, appearance and overall acceptability scores. For freshwater catfish smoked with Acacia, Prosopis, Neem and Coconut husks, scores for taste, appearance and overall acceptability were not significantly different (p<0.05). Insects were first detected in the marine catfish smoked by Acacia and Prosopis on day 35, 48 and 56 recording score 1, 2 and 3 respectively. For Coconut husk and Neem smoked marine catfish, insects appeared on day 48 and 56 with scores of 1 and 2 respectively. In the freshwater catfish smoked by Prosopis, insects were first noticed on day 35 and 48 with scores of 2 and 3. For those smoked with Acacia and Coconut husks the first insect attack was on day 48 with a score of 1 and scores of 2 and 3 respectively on day 56. The first insect attack on Neem smoked catfish was day 56. Mould was first detected in the marine catfish smoked with Prosopis and Coconut husks on day 35 and on Acacia and Neem on day 48 of storage. In the freshwater catfish, mould was first detected in the fish smoked by Acacia, Prosopis and Coconut husks on day 14 of storage and on fish smoked with Neem on day 56. The Neem tree delays insect and mould attack in smoked fish during storage. The percentage moisture recorded on day 0, 14, 21, 28, 35, 48 till 56 correspond to days when mould was noticed on the fish during storage and it increased with storage time. The 4 trees can be used in marine and freshwater catfish smoking for human consumption.

The influence of lipid content and pretreatment methods (blanching and brining) on proteins conformation in fish (Capelin, Mallotus v illosus ) during drying and smoking were assessed. Soluble protein fractions were examined through changes in salt‐soluble proteins, sulfhydryl groups, and disulfide bonds contents. The salt level and moisture content were also evaluated. Conformational changes in muscle protein were significant ( p < 0.05) after blanching and during initial drying when moisture content and dryness rates were high. Salt‐soluble proteins and total sulfhydryl groups contents reduced, whereas available sulfhydryl group and disulfide bonds contents intensified. The conformational changes were explained by muscle protein denaturation and aggregation ascribed to high temperature and dehydration during processing. The study reports fish protein denaturation to have reduced protein solubility as well as the nutritional value (loss of thermolabile compounds) and yield after smoking. More so, protein aggregation that was significantly ( p < 0.05) higher in dried blanched fish could have reduced the dried fish sensory quality. Blanching pretreatment is thus not suitable for commercial capelin drying. Lipids were found to have protective effect against fish protein conformation.

This study examined the market linkages and distribution channels of cultured, captured and imported fish in Kenya. A total of 113 fish traders' questionnaires and 10 key informant interviews were administered. Secondary data from published and unpublished records were used to complement primary data. Fish traders were literate enough to express themselves and were well equipped to assess market trends and channel. Fish trade was predominantly in the hands of women (66%). Consumers and middlemen (agents) were able to buy fish directly from producers. There was no significant association (p>0.05) between age, gender and the level of education with regards to the main business. There was correlation between gender and the main business function (χ2=3.921; df=2; p=0.141); the level of education and main business function (χ2=12.842; df=10; p=0.233) and the age distribution against the main business function (χ2=11.044; df=10; p=0.354). Recommendations include improvement of transport networks, promoting a political free environment for trade, regulating trade of imported Chinese fish, promoting a comprehensive fish marketing system including fish auction through strengthening linkages along the market value chain and traders should form strong cooperative societies to ease on the challenge of credit issuance from finance institutions.