AU2017203035A1 - Liquid mussel protein hydrolysate - Google Patents

Abstract

Abstract The invention relates to hydrolysed mussels and more particularly relates to a method of producing hydrolysed protein product by adding minced mussels to a hydrolysis tank, adding a combination of enzymes in stages while maintaining the pH generally constant in the tank, hydrolysing until the minced mussel has liquefied, and stabilising the liquid product by the addition of organic acid and/or molasses.

Description

LIQUID MUSSEL PROTEIN HYDROLYSATE Field of the Invention

The invention relates to hydrolysed mussels and more particularly relates to a method of producing hydrolysed protein product from NZ Blue Mussels and NZ Greenshell™ Mussels.

Background to the Invention

The applicant is one of the main players in the New Zealand fishing industry, catching and processing fish harvested according to the New Zealand quota management system, a sustainable fishing resource. The applicant also operates its own mussel farms in the Marlborough Sounds.

The applicant wanted to utilise blue mussels and broken or small Greenshell™ mussels and make them into a valuable product. NZ Greenshell™ Mussel powder is widely used for various health benefits in both animals and humans. Currently most fishing companies/mussel farms see the blue mussels as a waste material and no real market is found in New Zealand.

Mussels comprise 50% shell and 50% meat. The applicant’s aim is to make a liquid product, in a cost effective way, which will retain all the mussels’ benefits including amino acids, proteins, naturally occurring vitamins, minerals and omega 3 complexes and mucopolysaccharides.

To achieve these qualities in the product the applicant had to accept a procedure feasible as a commercial scale production.

Protein hydrolysis by commercially available proteases has become very common. Enzymatic hydrolysis using added enzymes brings a lot of advantages when compared to autolytic process and chemical hydrolysis.

The applicant’s research of the published literature in this field revealed no successful commercial scale production had been achieved.

An object of the present invention was therefore to create a commercial production process for hydrolysing mussels to produce a hydrolysed mussel liquid product and other derivative products.

Summary of the Invention A process for the production of Hydrolysed mussels in which the process steps include:

Mincing the whole mussels including shell

Increasing the temperature of a hydrolysis production tank to above ambient temperature;

Adding minced mussels to the hydrolysis tank and adding a combination of enzymes in stages while maintaining the pH generally constant in the tank;

Hydrolysing until the minced mussel has liquefied; and

Stabilising the liquid product by the addition of organic acid and/or molasses.

The addition of commercial exogenous enzymes to the mussel meat tissue reduces the time required to obtain a similar degree of hydrolysis and allows a good control of the hydrolysis and size of the peptides obtained. Mostly the industrial proteases are derived from GRAS microorganisms and to a lesser extent from plant and animal source.

Derivative products can be manufactured according to whether organic acid or molasses (or both) is used to stabilise the protein product.

Description of a Preferred Example

The screening and combinations of enzymes used are important in order to achieve the desired degree of hydrolysis. The selection of an ideal combination of enzymes to achieve the final product was a significant task in this process.

Alcalase 2.4L (a proteolytic endo peptidase enzyme derived from Bacillus licheniformis), Neutrase (a neutral protease), Protamex (a protease enzyme), Amylase (Novozymes, Denmark), Viscozyme L (a Beta-glucanase enzyme), Papain (a protease enzyme derived from the latex of Carica papaya), Ensidase PTX (an alkaline protease from Bacillus licheniformis), Cellulase, Protex 26L (a bacterial alkaline protease derived from Aspergillus niger), Bromalein (an enzyme from pineapple) and Ficin (from fig latex (protease)) were used during trials.

Scientific papers provided general guideline for the selection of optimum conditions for the hydrolysis but the final selection of the enzyme combination and its optimal pH and temperature conditions for making hydrolysed mussels (liquid mussel protein hydrolysate) were determined by an extensive time consuming process of trial and error.

The key findings were that hydrolysed mussels can be manufactured successfully on a commercial scale, while still retaining all the goodness of the mussels, by industrial enzymes.

The best result is obtained when a particular combination of enzymes is used.

Initial trials were limited only by using two different proteases but later on it was found out that a small quantity of a further enzyme was also required to digest the gut and intestinal tissues.

The task required the applicants to identify the optimum temperature conditions ideal for the combination of enzymes to act on the mussel tissues. Specific data sheets of the enzymes provided the information of effective temperature range. After several trials an optimum temperature was identified which did not denature one or the other enzyme activity.

The most striking advantage of the preferred process is that the hydrolysis of mussels can be carried out without altering the pH. A summary of an example protocol for making hydrolysed mussels by the applicant is: MINCE:

Mince whole mussels HYDROLYSE: 1. Put the minced mussels into the digester, and for every 1,000 kg of minced mussels in the digester add: a) 1.5 Litres Protease Enzyme (Papain) b) 1.5 litres Protease Enzyme (Alcalase) c) 750 ml Amylase Enzyme (BAN480L) 2. Increase the temperature of the digester to above ambient temperature, preferably, 60°C to 70°C for 4 to 12 hours or until mussel meat has liquefied. STABILISE:

Stabilise the hydrolysed mixture by adding:

Method One: a) 500 ml Rosemary Extract (Antioxidant) - Optional b) 1 kg Vitamin C (Antioxidant) - Optional c) 100 kg Citric Acid

Method Two: a) 500 ml Rosemary Extract (Antioxidant) - Optional b) 1 kg Vitamin C (Antioxidant) - Optional c) 114 Litres Molasses (or Sorbitol)

Method Three: a) 500 ml Rosemary Extract (Antioxidant) - Optional b) 1 kg Vitamin C (Antioxidant) - Optional c) 100 kg Citric Acid, then then add Molasses (or Sorbitol) to make the end product more palatable.

Thus by the invention there is provided a process for producing Hydrolysed Mussels from blue mussels and broken or small Greenshell™ mussels. It will be apparent to persons skilled in the art that the amount of ingredients specified in accordance with the above protocol are approximate only and may vary without significantly affecting the properties of the liquid mussel protein product.

There is also provided a method for producing derivative products based on the different liquid mussel protein products under the three methods described above.

For example, the product produced under method one above can be used for making animal or fish feed pellets.

Alternatively, the product produced under method two or three above can be used to make animal lick blocks by including the additional steps of: a) increasing the product temperature to 80°C, then adding in approximately 31.8% Gelatin, and stirring until the Gelatin is completely soluble; and b) Pouring the hot product mixture into containers, and allowing it to cool and set.

Preferably, the approximate ratio of ingredients in the animal lick blocks will be as follows:

Hydrolysed Mussels 25 kg 56.8%

Molasses (or Sorbitol) 5 kg 11.4%

Gelatin 14 kg 31.8%

In another alternative embodiment, the product produced under method one above is put through a vacuum spray dryer to turn it into a powder. This powder can then be used to make fertiliser or animal or fish feed pellets (replacing the fishmeal commonly used in a number of products).

The invention has been described by way of example only and it is envisaged that improvements and modifications can take place without departing from the scope of the attached claims. While the invention has been illustrated and described in detail in the foregoing description, such illustration and description are to be considered illustrative or exemplary and non-restrictive; the invention is thus not limited to the disclosed embodiments. Features mentioned in connection with one embodiment described herein may also be advantageous as features of another embodiment described herein without explicitly showing these features. Variations to the disclosed embodiments can be understood and effected by those skilled in the art and practicing the claimed invention, from a study of the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims (15)

1. What We Claim Is:

   1. A process for the production of a stabilised hydrolysed mussel in which the process steps include: a. increasing the temperature of a hydrolysis production tank to above ambient temperature; b. adding minced mussel to the hydrolysis production tank and adding a combination of enzymes as herein defined in stages while maintaining the pH generally constant in the tank; c. hydrolysing until the mussel meat has liquefied; and d. liquefy the shell and stabilise the liquid product by the addition of organic acid and/or molasses or sorbitol without adding water to lower the pH.
2. 2. A process as claimed in claim 1 wherein commercial exogenous enzymes are added to the minced mussels to reduce the time required to obtain a desired degree of hydrolysis while allowing a good control of the hydrolysis and size of the peptides obtained.
3. 3. A process as claimed in claim 1 or claim 2 wherein the enzyme(s) are derived from generally recognised as safe (GRAS) microorganisms.
4. 4. A process as claimed in claim 3 wherein the enzyme(s) are to a lesser extent derived from plant and animal source.
5. 5. A process as claimed in claim 4 or claim 5 wherein the enzyme(s) are one or more of alcalase 2.4L, neutrase, protamex, amylase (Novozymes, Denmark), viscozyme L, papain, ensidase PTX, cellulase, protex 26L, bromalein and/or ficin.
6. 6. A process as claimed in claim 1, wherein the acid comprises citric acid and/or other acid.
7. 7. A process as claimed in claim 1, wherein the organic acid comprises citric acid and/or other acid to liquefy the mussel shells and further includes the step of adding molasses or sorbitol for stability and palatability.
8. 8. A process as claimed in claim 1, wherein approximately 11.4% molasses or sorbitol is added to stabilise the mixture.
9. 9. A process as claimed in claim 6 or claim 7 further including the steps of a. Increasing the temperature of the liquid product to approximately 80°C; b. adding approximately 31.8% gelatin; c. stirring until the gelatin is completely soluble; d. pouring the liquid mixture into containers to allow to cool and set.
10. 10. A liquid product manufactured by the process in claim 1 or 6 or 7.
11. 11 .An animal lick product manufactured by the process in claim 9.
12. 12. An animal or fish feed pellet produced using a product manufactured by the process in claim 6.
13. 13. A powder produced by putting the product manufactured by the process in claim 6 through a vacuum spray dryer.
14. 14. An animal lick product as claimed in claim 11 comprising ingredients in approximately the following ratios: Hydrolysed Mussels, 56.8%; Molasses (or Sorbitol) 11.4%; and Gelatin, 31.8%.
15. 15. A process as claimed in claim 1 and substantially as hereinbefore described.