Brine and Post-Frying Oil Management in the Fish Processing Industry—A Concept Based on Oleaginous Yeast Culture

Agata Fabiszewska,Dorota Nowak,Bartłomiej Zieniuk,Małgorzata Wołoszynowska,Katarzyna Wierzchowska

doi:10.3390/pr10020294

Abstract

Waste management solutions including the valorization of waste materials in biotechnological processes is an important issue needing to be explored. A significant amount of waste is being generated by the food industry. In this study, an attempt was made to utilize two fish industry wastes simultaneously—waste brine and post-frying oil from frying fish fillets in Yarrowia lipolytica culture with high single cell oil synthesis yield. Oxygenation in the culture medium had a positive effect on the biosynthesis efficiency of microbial oil, resulting in the highest content of lipids in yeast cells at the level of 0.431 g/g d.m (dry mass). Y. lipolytica yeast preferentially accumulated oleic acid and linoleic acid, and the high content of linolenic acid, valuable from a nutritional point of view, was also found in microbial oil. This study proved that the use of post-frying rapeseed oil gives a chance to obtain valuable storage lipids in Y. lipolytica yeast cells via ex novo biosynthesis pathway. Furthermore, the wastewater stream could be limited using a waste brine as a solvent in medium preparation, but the brine share should not exceed 30% so as not to inhibit yeast cell growth.

Highlights

In 2015, the total amount of fishery products was estimated at 169.2 million tonnes, of which 6.4 million tonnes were accounted for by European Union countries
The maritime economy includes fishing and fish processing, and in the light of circular economy, the waste management solutions related to the fish industry are important
Strong evidence was found that factors influencing the biomass yield and the synthesis of microbial oil by Y. lipolytica yeast were the access of oxygen and the pH of the culture medium

Summary

Introduction

In 2015, the total amount of fishery products was estimated at 169.2 million tonnes, of which 6.4 million tonnes were accounted for by European Union countries. Indonesia, Peru, India, the Russian Federation, the United States of America and Vietnam are countries accounting for almost 50% of total global capture fish production, but global aquaculture production of farmed aquatic animals has been dominantly in Asia (89% share) [2]. The maritime economy includes fishing and fish processing, and in the light of circular economy, the waste management solutions related to the fish industry are important. Unprocessed wastes are a habitat for pathogenic microflora that can reach farmlands, and along with the crops, reach consumers’ tables [5,6] It is recommended by the Sustainable Development Goals by

Objectives

Methods

Results

Discussion

Conclusion