Storage stability of an ornamental fish diet enriched with palmyrah fruit (Borassus flabellifer) pulp

Abstract

The ornamental fish industry depends on high-quality diets for health and growth. Many available or formulated feeds degrade over time, reducing nutritional value, palatability, and cost-effectiveness. Over ten months, this study investigates the storage stability of an ornamental fish diet enriched with a novel feed additive, Palmyrah fruit (Borassus flabellifer) pulp. The quality of the experimental feed was assessed in terms of its nutritional composition, microbial properties, and cost-effectiveness, which were compared with the commercial diet. Users’ perception of the experimental diet was assessed using a questionnaire. Statistical analysis was performed using Minitab Statistical Software 2021. The results showed that the experimental feed is not harmed by aflatoxin contamination (20 μg kg^-1) and total bacterial count (1.5 x 10³ cfu g^-1). The protein content of experimental and commercial feeds remained constant for ten months (42.17 ± 0.06 and 40.53 ± 0.37, respectively), although the fat content of the experimental feeds did not differ significantly (P < 0.05) at the three storage periods. A downward trend in the proportion of all fatty acids in both feed types was observed after ten months of storage. Despite a rise in moisture, it remained under 10%, preventing microbial growth. The stakeholders have been receptive to the experimental feed for ornamental fish, which is 22 times more cost-effective than commercial feed on a small scale. Our findings indicate that the experimental feed remains of stable quality for ten months of storage under room temperature (25 - 33 ºC), which offers a sustainable and cost-effective solution for the aquaculture industry.