Decreasing fishy odour from catfish (Clarias sp.) flour as a food ingredient by using various soaking solutions

Abstract

Catfish (Clarias sp.) has become one of Indonesia's most popular aquaculture products. However, it is very perishable and has a short shelf life. It can be preserved by drying it into catfish flour. Therefore, it is easy to be further utilized for substituting other flour in the production of foods to enhance their nutritional value. However, the fishy odour of catfish flour hinders this flour for wide utilization. Various soaking solutions such as lime juice, lemon juice, milk, coconut water and vinegar are commonly used to decrease the fishy odour. This study aimed to establish a sensory lexicon by Quantitative Descriptive Analysis (QDA) and to evaluate the pH and trimethylamine (TMA) value of catfish flour soaked by various types of soaking solutions. According to a sensory evaluation, 19 attributes were identified. The coconut water at 5% was determined as the most preferred with a score of 0.74±0.72. It had a high intensity of saltiness and smoky fish aroma (pleasant attributes), as well as a low fishy smell (unpleasant attribute). The lime juice at 5% had the strongest fishy smell (unpleasant attribute) and umami taste (pleasant attribute). The pH values of all samples were in the range of 4.16-6.59. The highest pH value was found in milk at 5%, whereas the lowest one was found in lime juice at 100%. TMA values ranged from 2.44 to 5.19 mg N/100 g catfish flour. The highest TMA value was found in lime juice at 5%, but it was within an acceptable range and lower than the control (6.10±0.86 mg N/100 g catfish flour). The results of this study indicated that catfish flour made from catfish meat soaked in lime juice, lemon juice, milk, coconut water, and vinegar provided good quality characteristics, as well as pH and TMA values within an acceptable range. Therefore, they had the potential to be further developed and could be considered as an alternative for other flours in developing food products.