Fish quality and training in sensory evaluation of fish freshness

The workshop was developed and conducted in cooperation with MATÍS, TAFIRI and the Tanzanian Regional Government in the Kigoma District. The purpose was to promote better handling of fish on board and after being landed, and to strengthen the FOs and FRs in assessing the quality along the value chain of fish in the Kigoma region. Based on an analysis of current practices and sensory evaluation methods the idea for a workshop emerged and in January 2019 research and preparation work was carried out (see travel report January 2019, Þór Ásgeirsson) and a decision was taken to hold a workshop in November 2019.

Main objectives:

1. To analyse handling and quality of fresh and processed fish in the Kigoma region

2. To co-create sensory evaluation schemes suitable for landed fish and main products of the fish

3. To provide teaching materials, including guidelines for handling and the development of sensory scheme, for further use in the Tanzania education system

4. Training of FOs and FRs in fish quality, sensory evaluation and in using the sensory evaluation scheme both at the landing sites and markets

Description

There were 16 workshop participants (see accompanying attendance list) made up of 13 FOs and 2 FRs and 1 representative from the ministry in Dar es Salaam. All participants fully participated in the workshop daily from 8a.m. to 4 or 5 p.m.

DAY 1: focused on registration, introductions (mini-needs analysis) basic fish handling and storage, the situation in the Kigoma district and what could be improved (see day 1 storage for slides and group feedback).

DAY 2: focused on sensory evaluation, developing a QIM scheme (see day 2 storage for slides and group feedback on current QIM scheme).

DAY 3: focused on QIM schemes, the results of the pre-trial, testing the pre-scheme, a visit from an export representative and the development of a scheme to be used in the field.

DAY 4: focused on testing the QIM scheme for Dagaa in the field. The chosen landing site had to be changed last minute from Kibritza to Katonga due to the weather conditions and availability of fish. In the afternoon the pre- scheme for Mgbuka was teated and evaluated ready for the field visit on Friday.

DAY 5: The planned field trip to Kibirizi had to be cancelled due to weather conditions, however the schedule was adapted and Mgbuka were brought into the lab for QIM testing. In the afternoon the workshop was evaluated (see results) and each participant received a certificate of participation and a memory stick containing all the workshop presentations, results of the group discussion sessions, QIM schemes developed and contact details. A plan for further testing of the QIM schemes developed was drawn up and it was decided that each participant would carry out three tests on each fish species producing 6 sets of data. Ritha would oversee, collect and collate this data for further action.

Outcome:

The main outcome of the training workshop were two sensory schemes, the Quality Index Method for iced whole Dagaa and iced whole Mgebuka. The schemes were based on the outcome of pre-trials, carried out by Ritha, who drafted the schemes during observation of the two species from catch until spoiled. The purpose of the pre-trials was a) make the draft schemes based on the methodology of the Quality Index Method for the iced whole Dagaa and the iced whole Mgbuka and b) estimate maximum shelf life of the two species i) when iced from catch, reflecting the best storage conditions and ii) when stored at room temperature (28-32°C), reflecting the current and most common storage conditions. Part b i) was not carried out as planned, as the fish was stored at -10°C and therefore not reflecting the spoilage rate and spoilage characteristics when stored in ice. Therefore, information about estimated shelf life were not achieved. For condition b ii) the Dagaa was spoiled after 6 hours and Mgebuka after 6-8 hours. For part a) draft schemes were obtained for both species stored at room temperature.

The workshop participants were introduced to the importance of good handling with demonstration of the importance of good handling and processing, linked with higher value and extended market possibilities. After introduction to sensory evaluation, training of panelists, sensory evaluation of fish, methodology, training and development procedures of the Quality Index Method, the 16 participants of the workshops were introduced to the draft schemes and received training in applying the schemes in evaluation of freshness of Dagaa and Mgebuka stored in ice. For Dagaa, all samples were collected and stored in ice to be evaluated after 0, 2 and 4 days of storage. For Mgebuka, a part of the samples was stored in room temperature for 6 hours after catch followed by iced storage for 5 days. Other samples of Mgebuka were iced after catch to be evaluated after 0 days and 5 days. The workshop participants gave feedback to the scheme design during practical session and group discussions. Based on their feedback, the schemes were modified and tested ones again by the participant, on landing site for Dagaa and at the laboratory for Mgbuka.

Based on this, the 16 participants have now received training in evaluation of fish freshness, obtained deeper understanding of the characteristics of the fish species with storage time.