Preparation of High-Quality Fermented Fish Product

Summary

The goal of the protocol is to provide an industrialized fish fermentation technique based on inoculation of Saccharomyces cerevisiae.

Abstract

This protocol provides a method for preparation of industrialized fermented fish product with sturgeon (Aquilaria sinensis) meat product. The procedures were: (1) pretreatment of farmed sturgeon including decapitation, evisceration, skinning-off, cleaning and cutting; (2) marinating fish cubes in 6-12% (w/v) salt solution (1:1, fish cube mass to solution volume); (3) drying fish cubes to a water content of 50-60% by hot air (40-60 °C) or by vacuum; (4) fermentation involving inoculating fish cubes with 0.4-1.6% (w/w) S. cerevisiae in flavor solution to fish cubes and fermenting at 25-35 °C for 6-10 h; (5) sealing fish cubes in vacuum packages with marinating and fermenting solutions; (6) sterilizing at 115-121 °C for 10-20 min. The sturgeon meat product prepared by this method has delicious taste which is mellow and thick, has various types and large amounts of volatile flavor compounds such as alcohols and esters which could mask musty and unpleasant odor from fish, has moderate salt content but good texture properties such as high springiness, gumminess and chewiness, and has bright russet color and attractive appearance. This new technique could also be applied in the processing of other fish to provide convenient fish snack foods which could be stored at room temperature. It is appropriate for both marine and freshwater fish.

Introduction

Current commercial marinated fish product in China has the problem of heavy salty taste, insufficient wine aroma, poor elasticity and pale color, which decreases the acceptability to consumers. Therefore, a new technique for a high-quality fish meat product with wine aroma needs to be created and optimized.

In recent years, application of modern fermentation techniques in meat and fish has attracted attention from more and more researchers^1,2,3,4. By inoculation of starter cultures into meat and fish, food safety ....

Protocol

1. Sample preparation

1. Thaw frozen sturgeon meat under flowing water below 20 °C. Then, clean, skin off and cut the fish into cubes (2 cm × 2 cm × 1.5 cm).
   NOTE: Raw material could be fresh or frozen sturgeon meat.
2. Mix fish cubes with 6-12% (w/v) salt solution at a rate of 1:1 (fish cube mass to solution volume), at 10 °C for 1-3 h.
3. Put the marinated fish cubes onto a stainless-steel gridding plate and dry fish cubes at 40-60 °C for about 6-10 h by hot air, or dry the fish cubes in vacuum, until the water content decreases to 50-60%.
4. Mix dried fish cubes with the flavor solution inoculating 0.4-1....

Results

The suitable salt concentration, marinating time and temperature make the product’s textural quality better. The best marinating conditions were as follows: the salt concentration of 8% in the marinating solution; marinating time of 2 h; and marinating temperature of 10 °C. See Figure 1.

In drying process, the final moisture content and drying temperature could influence the texture and sensory quality. The best drying conditions were as follows: moisture content .......

Discussion

In this study, a new technique for the production of high-quality fermented fish product with wine aroma and tests for sensory properties are provided. The key processes of this technique are marinating, drying, fermentation and sterilization. In the marinating process, the salt concentration, the temperature and the time all affect the textural properties of the fish. The hardness and chewiness of the product increase gradually with the increase of salt concentration (0-12%, w/v) and the prolongation of marinating time .......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
2,4,6-trimethylpyridine	Tokyo Chemical Industry Co., Ltd.	Purity 98%
Colorimeter	Hunterlab	UltraScan Pro1166
DB-WAX column	Agilent	30 m × 0.25 mm × 0.25μm
Digital pH meter	Mettler toledo Instrument (Shanghai) Co., Ltd.	DELTA-320
Drying oven	Shanghai Yiheng Scientific Instrument Co., Ltd.	DHG-9070A
Frozen sturgeon	Huada Marine Industry Group Co., Ltd	-
Gas chromatograph-mass spectrometer	Thermo Fisher Scientific	TSQ Quantum XLS
Humidities incubator	Shanghai Yiheng Scientific Instrument Co., Ltd.	LHS-250HC-II
Saccharomyces cerevisiae	Angel Yeast Co., Ltd	-
Spices	Auchan Supermarket	-
Sterilization pot	Longqiang Machinery Technology Co., Ltd.	RHS-03-700
Supelco	Sigma	65μm, PDMS/DVB
Texture analyzer	Stable Micro Systems, Ltd.	TA-XT2i
Vacuum package machine	Quanzhou Yiminxin Electromechanical Co., Ltd.	YMX-958-10L