Identification of the Specific Spoilage Organism in Farmed Sturgeon (Acipenser baerii) Fillets and Its Associated Quality and Flavour Change during Ice Storage.

Zhichao Zhang,Pinglan Li,Ruiyun Wu,Meng Gui,Zhijie Jiang

doi:10.3390/foods10092021

Abstract

Hybrid sturgeon, a popular commercial fish, plays important role in the aquaculture in China, while its spoilage during storage significantly limits the commercial value. In this study, the specific spoilage organisms (SSOs) from ice stored-sturgeon fillet were isolated and identified by analyzing their spoilage related on sensory change, microbial growth, and biochemical properties, including total volatile base nitrogen (TVBN), thiobarbituric acid reactive substances (TBARS), and proteolytic degradation. In addition, the effect of the SSOs on the change of volatile flavor compounds was evaluated by solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). The results showed that the Pseudomonas fluorescens, Pseudomonas mandelii, and Shewanella putrefaciens were the main SSOs in the ice stored-sturgeon fillet, and significantly affect the odors by changing the volatile compounds in the sturgeon. Compared with the fresh sturgeon, the appreciable increase of polycyclic aromatic hydrocarbons and tetramethyl-pyrazine might be the spoilage indicators of the sturgeon contaminated by P. fluorescens; the appreciable increase of 1-octen-3-ol and (z)-2-penten-1-o might be the potential marker of the sturgeon contaminated by P. mandelii; and the appreciable increase of 1-(3,3-dimethylbicyclo [2.2.1] hept-2-yl)-ethanon and butylated hydroxytoluene were associated with S. putrefaciens. This study reveals the relationship between the SSOs and flavor changes in sturgeon fillets, which will contribute to the sturgeon preservation and shelf-life extension.

Highlights

Sturgeon, one of the oldest fish in the world, is of great biological and economical importance
In order to further clarify the relationship of microbial community structure in fish meat with different storage time, an unweighted pair group method with arithmetical means (UPGMA) method was used to construct the DGGE map
The results are as shown in Figure 1B: according to the similarity of bacterial communities, the flora at 0, 3, 6, and 8 days are grouped into one cluster, and that on day 10, 12, 14, and 16 are in a separate cluster

Summary

Introduction

One of the oldest fish in the world, is of great biological and economical importance. Due to the high water content, rich nutrients, high endogenous enzyme activity, and near neutral pH value, sturgeon meat products are easy to get spoilage with deteriorated taste and flavor under the joint action of endogenous enzymes and microorganisms during the processing, transportation, and storage [5], which can cause health issue as well as reduce its commercial value. Just the small portion of microorganisms cause fish spoilage during storage due to their great tolerance to the preservation conditions, and those microorganisms are named as “specific spoilage organisms (SSOs)” [7,8]. Different microorganisms show different spoilage characteristics, especially in fish Biogenic amines, such as histamine, putrescine and cadaverine, are considered as indicators of fish spoilage [12]. The ammonia like odor and sour taste were the main problem to maintain the quality during storage

Methods

Results

Conclusion