# Macroscopic Physical Properties and Nutrient Content in the Fermentation of Pangasius Waste by Single Cultures and Microbial Consortiums and Their Potential for Feed

## TL;DR

This study explores using microbial fermentation to convert fish waste into nutrient-rich feed for livestock, finding that a specific microbial consortium is most effective.

## Contribution

The study introduces a novel microbial consortium for converting fish waste into high-protein feed, offering an affordable and accessible protein source for livestock.

## Key findings

- A microbial consortium of Pseudomonas aeruginosa, Rhizopus microsporus, and Yarrowia lipolytica produced FPW with 52.02% protein after 4 days of fermentation.
- The best macroscopic physical properties and nutrient content were achieved with a 15% dose of the microbial consortium.
- Fermented pangasius waste is recommended as a viable protein source for poultry feed.

## Abstract

Fish waste processing through biological technology using fermentation microbes is an important concern in handling fishery waste, because fermentation can decompose organic waste materials into useful products and reduce pollutant levels. The purpose of the study was to select three types of microbes based on macroscopic properties and nutrient content of fermented pangasius waste (FPW). In the first stage, the fermentation of pangasius waste with eight species of microbes (three of bacteria, three of fungi, and two of yeast) is cultured in a single fermentation solid‐state medium. Each type of microbe that produces the highest number of colonies and nutrient content of FPW products in a single culture is then selected and used for consortium culture. The study used the nested, completely randomized design method, and the data were analyzed with ANOVA and Duncan's multiple range test. The results of single cultures of Pseudomonas aeruginosa (Pa), Rhizopus microsporus (Rm), and Yarrowia lipolytica (Yl) produced the best FPW products at 4 days of fermentation. The results of a consortium P. aeruginosa, R. microsporus, and Y. lipolytica (Pa + Rm + Yl) at a dose of 15% and fermentation for 4 days produced the best macroscopic physical properties, and its effect on nutrient content, obtained at a dose of 15% and fermentation for 4 days (protein 52.02%, fat 29.24%, and crude fiber 2.19%). The conclusion was that the consortium of three types of microbes (Pa + Rm + Yl) was more effective in treating FPW. FPW products are recommended as feed ingredients as a source of protein for poultry.

This study is a new finding regarding the diversification of protein source raw material for livestock, namely, in the form of fermented pangasius waste. It is hoped that these findings can provide information regarding the use of protein source raw materials that are relatively more affordable and easy to obtain.