FRESH WATER METHODS FOR REDUCED FLUORINE CRUSTACEAN COMPOSITIONS

Abstract

Fluorine being present in the exoskeleton of crustaceans, and especially krill represents a problem for using hill as a source for food, feed, food additives and/or feed additives. There has been developed a process for removing such fluorine from krill material by subjecting the krill to disintegration and to an enzymatic hydrolysis process prior to or simultaneously with a removal of the exoskeleton particles producing a fluorine-reduced product. Inherent in the disclosed process is the ability to process krill material with a high polar lipid content for producing superior quality, low fluorine, products suitable for the food and feed as well as the pharmaceutical, neutraceutical and cosmetic industry.

Claims

1. A method, comprising: a) providing a crustacean catch; b) adding fresh water to said crustacean catch; c) disintegrating said crustacean catch with a disintegration apparatus in said fresh water to produce a disintegrated crustacean catch comprising shell and carapace particles, wherein said particles has a size not larger than 25 mm; d) adding one or more proteolytic enzymes; e) hydrolyzing said disintegrated crustacean catch with said one or more proteolytic enzymes to produce a hydrolyzed crustacean material; and f) separating said shell and carapace particles from said hydrolyzed crustacean material with a particle removal device to produce a proteinaceous crustacean fraction having an at least 85% reduction in fluorine content as compared to a fluorine content of 1500 ppm in a conventional crustacean meal.

2. The method of claim 1 wherein said particle removal device removes a solids fraction from said hydrolyzed crustacean material.

3. The method of claim 1, wherein said hydrolyzing has a duration selected from the group consisting of no longer than 100 minutes and within 60 minutes.

4. The method of claim 1, further comprising deactivating said one or more proteolytic enzymes.

5. The method of claim 4, wherein said deactivating occurs at a step selected from the group consisting of before said separating, during said separating and after said separating.

6. The method claim 1, wherein said proteinaceous crustacean fraction comprises a polar lipids concentrate.

7. The method of claim 6, wherein said polar lipids concentrate comprises phospholipids.

8. The method of claim 1, wherein said disintegrated crustacean catch has a particle size ranging between approximately 0.5-10 mm.

9. The method of claim 1, wherein said crustacean catch and said fresh water are in a ratio of 0.5 to 1.5 (w/w).

10. The method of claim 1, wherein said particle removal device comprises a long clarification/separation zone and is operated with a gravitational separation force between 1,000 and 1,800 g.

11. The method of claim 1, wherein said particle removal device is a sedicanter.

12. The method of claim 1, wherein said fresh water is heated within 1-300 seconds after said disintegrating.

13. The method of claim 1, wherein said one or more proteolytic enzymes are selected from the group consisting of alkalase, neutrase, microorganism enzymes and plant enzymes.

14. The method of claim 4, wherein said deactivating comprises heating said fresh water to a temperature over 90 C.

15. The method of claim 1, wherein said crustacean catch is a fresh crustacean catch.

16. The method of claim 1, wherein said crustacean catch is selected from the group consisting of a krill catch and an Antarctic krill catch.

17. The method of claim 1, wherein said method is performed on a fishing vessel.

18. The method of claim 17, wherein said crustacean catch has been immediately landed on said fishing vessel.

Description

EXAMPLE

[0048] A fraction of 500 kg from a 10 ton catch of Antarctic krill was immediately (maximally 20 minutes after catch) shredded through a knife cutter into pieces of a particle size of 3-6 mm at a temperature of 1-2 C., and immediately thereafter added 500 litres fresh water and alkalase in an amount of 0.2% (w/w) of the krill wet weight and then heated to a temperature of 55-60 C.

[0049] The enzyme was allowed to function for 45 minutes at said temperature. The material was thereafter fed to a decanter operated at the following conditions; Temperature: 90 C., gravity force at 1400 g and with a feed rate of 1.2 ton krill/water/enzyme suspension per hour causing a separation of the fluorine-containing fine particles and a liquid proteinaceous fraction exiting the decanter. The material was then heated to a temperature of 93 C. in order to terminate the enzymatic hydrolysis and denaturing/agglomerating the insoluble protein together with polar lipids for following separation. The liquid proteinaceous fraction was immediately thereafter transferred to a separation step by a specially designed decanter (sedicanter) mentioned supra, separating the solid phase containing insoluble proteins and polar lipids concentrate (PPC) from the hydrolysate.

[0050] The PPC are thereafter mixed with a food-grade anti-caking agent, dried in a thin film vacuum drier and packed in air tight bags under nitrogen atmosphere. The aqueous soluble protein (hydrolysate) and neutral lipid phase are feed to a separator separating the neutral lipid phase from the hydrolysate. The oil is stored in air tight containers under nitrogen atmosphere.

[0051] The hydrolysate are continuously feed into a flash evaporator for dewatering/concentration giving a concentrated hydrolysate fraction (CHF) with dry weight of 55-70% and stored in air tight containers under nitrogen atmosphere.

[0052] A typical mass balance for processing of raw lean Antarctic krill is shown in table 1 below:

TABLE-US-00001 TABLE I Mass balance for processing of raw lean Antarctic krill. From 500 kg Dry weight Fraction raw krill in fraction PPC (Phospholipids/Peptide 80 kg 28% Complex) Dried PPC (with anti-caking 25 kg 97% agent) Hydrolysate 770 kg 6.1% CHF (Concentrated 78 kg 60% Hydrolysate Fraction) Fluorine-containing fine 45 kg 40% particles (shell and carapace fragments) Neutrals oils <5 kg 100%

BRIEF DESCRIPTION OF THE DRAWING

[0053] FIG. 1. A specially designed decanter with an extended separation path. This example is a FLOTTWEG SEDICANTER horizontal decanter centrifuge.