NO310173B1 - Process for Preparation of Essential Bacteria-Free Colostrum by Microfiltration - Google Patents

Abstract

Process for the production of substantially bacteria-free colostrum. characterized in that defatted colostrum (colostrum) is poured into a balance tank; the feed pump then pumps the retentate to a booster pump; the booster pump circulates the retentate past a diaphragm where the pressure difference in the diaphragm causes. it can be filtered; the retentate flows past a heating / cooling unit to maintain a constant operating temperature before returning to the booster pump; filtered colostrum (permeate) circulates past the filter to maintain a constant transmembrane pressure; the permeate is drained without pressure drop on the permeate side of the filter.

Description

The present invention relates to a method for the production of substantially bacteria-free colostrum by microfiltration.

Colostrum, or colostrum, is the breast milk secreted by mammals in the last part of pregnancy and the first days after birth. It is somewhat less fatty than the later milk and is rich in proteins, especially immunoglobulins. Colostrum has a number of outstanding and interesting properties, partly due to its high nutrient content. Colostrum's proteins and especially immunoglobulins can be used in countless areas.

Bovine colostrum can also have a high bacterial content, approx. 10<6->10<8> bacteria per ml. However, problems have long existed regarding methods for reducing the bacterial content in colostrum, in order to be able to produce a bacteria-free colostrum preparation.

Colostrum cannot be heat sterilized (pasteurized) to remove the bacteria, because heating denatures and coagulates the proteins (this is especially important when it comes to biologically active proteins).

A commonly used method in the technique of sterilizing solutions is microfiltration. However, microfiltration of colostrum has not been possible until now, because the casein in the colostrum immediately clogs the microfilters and makes filtration impossible (see German patent C 2 813 984).

PCT application WO 95/10192 describes a nutritious drink based on colostrum. Sterilization of this product was carried out by, after defatting in the conventional manner, first removing the casein by precipitation (with hydrochloric acid) and then microfiltering the resulting "whey".

US patent no. 5 147 548 describes the production of a sterile filtered colostrum solution with a retained content of casein. In the method according to this publication, a defatted colostrum solution is treated with hydrochloric acid, so that the casein precipitates at pH 4-5 and dissolves again when the pH is lowered to 2-3.5. The colostrum solution can then be microfiltered and the pH in the solution then brought back to the original value by adding NaOH. Such a method thus requires, in addition to no microfilter, two further steps which make the procedure for producing bacteria-free colostrum more complicated and far more expensive. Moreover, the product obtained by this method is not "natural" colostrum, due to the addition of acid, followed by base, which gives a higher salt content than in "natural" colostrum. A question mark can also be raised as to whether these additions of acid and base will affect and change the natural proteins in colostrum (especially the valuable immunoglobulins).

With the present invention, a method has surprisingly been found in which, after the fat has been removed, natural colostrum can be microfiltered directly without anything being done to the casein. With this method, a colostrum preparation is obtained in which the bacteria content is reduced by up to 99.9%, and where otherwise all natural components, apart from fat, are retained without any kind of additives or complicating and labor-intensive additional treatments. All previous attempts in the technique of microfiltration of defatted colostrum directly have been unsuccessful, and in US 5 147 548, column 1, it is thus stated that: "Filtration sterilization, the simplest and most effective method of eliminating the bacteria and the method that best protects the proteins, cannot be employed with colostrum because the casein immediately clogs up the filter".

In the present invention, it has surprisingly been found that colostrum can be microfiltered by using a larger booster pump and increasing the speed of the retentate.

In normal microfiltration of milk, the speed of the booster pump (the milk flowing through the filter) is 6 m<3>/hour. When micro-filtering colostrum, the filter will clog at the same speed.

In the present invention, it was found that by using a larger booster pump and increasing the speed of the retentate to between 7.2 and 7.8 m<3>/hour, colostrum is microfiltrated.

The present invention thus provides a method by which, by a simple microfiltration of natural, defatted colostrum, a substantially bacteria-free (99.9%) colostrum can be produced where the original components (especially the protein composition) are retained in substantially native form and without the use of some additives.

The method according to the present invention for producing substantially bacteria-free colostrum thus comprises: Defatted, natural colostrum (colostrum) is poured into a balance tank; the feed pump then pumps the concentrate to a booster pump which gives a speed of the concentrate of 7.2-

7.8 mVh; the booster pump circulates the concentrate through a filtering membrane where the pressure difference in the membrane allows it to be filtered; the concentrate flows past a heating/cooling unit to maintain a constant operating temperature before returning to the booster pump; colostrum that has been filtered (the filtrate) circulates past the filtration membrane to maintain a constant transmembrane pressure; the filtrate is drained without pressure loss on the filtrate side of the filter.

The method according to the present invention is illustrated by means of the following example.

Example

Microfiltration of colostrum

For this experiment, 40 kg of defatted, frozen colostrum was used.

Filtration system: Mini Mf system (dead volume approx. 7 kg) Filtration membrane: SCT ceramic membrane

Pore size: 1.4 u

Membrane area: 0.2 m<2>

The frozen colostrum was heated to 50 °C and microfiltered. Samples were taken and analyzed.

Table 1 below shows operating data for an experiment with microfiltration of colostrum.

Table 2 below shows analysis results from samples of the micro-sterilized colostrum with regard to microbe content, antibody content and dry matter content.

Claims (3)

1. Method for producing substantially bacteria-free colostrum by microfiltration, characterized in that defatted, natural colostrum (colostrum) is poured into a balance tank; the feed pump then pumps the concentrate to a booster pump which gives a velocity of the concentrate of 7.2-7.8 m<3>/hour; the booster pump circulates the concentrate through a filtering membrane where the pressure difference in the membrane allows it to be filtered; the concentrate flows past a heating/cooling unit to maintain a constant operating temperature before re-entering the booster pump; colostrum that has been filtered (the filtrate) circulates past the filtering membrane to maintain a constant transmembrane pressure; the filtrate is drained without pressure loss on the filtrate side of the filter. 2. Method according to claim 1, characterized in that the filtration membrane used is a ceramic membrane. 3. Method according to claim 1, characterized in that the bacterial content in colostrum is reduced by up to 99.9%.