Value added fish by-products - Nordic Innovation

• 9 samples containing 1.3% salt and 5% sucrose
• 9 samples containing 4% sucrose and polyphosphate
4 samples were stored at +2°C for 2 days, 16 samples at -18°C for 12 weeks and 16 samples
at -24°C for 12 weeks.
1.1.2.2.2 Microbiological analysis
Aerobic plate count was conducted according the procedures of Compendium of Methods for
the Microbiological Examination of Foods (APHA 1992).
1.1.2.2.3 Chemical analysis
Dry matter was calculated as the loss in weight during drying at 105°C for 4 hours (ISO
1983).
TVB-N content of samples was measured using direct distillation into boric acid (based on
AOAC 1990). The acid was then titrated with a diluted sodium hydroxide solution. The
unbound ammonia was calculated as g/16gN.
1.1.2.2.4 Water holding capacity and weight loss
Weight loss and water holding capacity (%) was determined by centrifuging of 2 g of the FPS
using Biofuge Stratos; Heraeus Instruments (GmbH&Co., Hanau, Germany). Temperature
interval was set at 5°C, speed 1350 rpm and the time was 5 min. After the centrifuging had
completed, the difference in weight of the samples before and after (centrifuging) was noted.
1.1.2.2.5 Viscosity
The viscosity was also analysed by using Bohlin BV88 viscometer (Bohlin Instruments,
England). A beaker containing 200 ml of sample was put inside a 500 ml beaker containing
crashed ice to control temperature. The instrument cylinder was immersed into the solution.
The viscosity of the sample was recorded after 20 seconds of operating instrument at 5 to 7°C,
speed setting 6, system switch 6. Measurements were done in triplicate. Viscosity was
reported as Pascal.
The Brabender viscosity of the fish protein solutions was determined using a Brabender®
Viscograph E coaxial viscometer (Brabender® OHG, Duisburg, Germany). The Brabender®
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