Microfiltration of human milk to reduce bacterial contamination
The present invention relates to a method for treating raw human milk to produce treated human milk having undetectable levels of bacteria. The milk is skimmed to produce skim human milk then subjected to microfiltration to yield a filtrate which has undetectable levels of bacteria, including Bacillus cereus . The resultant human milk can be further processed, used and/or sold.
1. An apparatus for producing microfiltered human skim milk, said apparatus comprising:
a jacketed process vessel for storing raw human milk;
a milk separator for separating the raw human milk received from the jacketed process vessel into a cream fraction and a human skim milk fraction;
a receiving jacketed process vessel for storing the human skim milk fraction from the milk separator;
a diatomite filter aid process vessel for storing diatomite filter aid;
a pre-filter housing for pre-filtrating the human skim milk from the receiving jacketed process vessel mixed with filter aid from the diatomite filter aid process vessel wherein said filter aid is added to said skim milk fraction in a concentration of from about 20 g/L to about 50 g/L, and wherein said filter aid has a permeability of from about 0.100 D to about 0.300 D, wherein the pre-filter housing comprises a pre-filter, and the filter aid is capable of filtering endospore bacteria from the human skim milk and preventing plugging of the pre-filter;
a microfilter housing for microfiltrating pre-filtrated human skim milk received from the pre-filter housing;
a skim jacketed process vessel for storing microfiltered human skim milk received from the microfilter housing.
2. The apparatus of claim 1 , wherein the microfiltered human skim milk produced from the apparatus has no more than about 10 1 bacteria per milliliter.
3. The apparatus of claim 1 , wherein the microfiltered human skim milk produced from the apparatus has no more than about 10° Bacillus cereus cell per milliliter.
4. The apparatus of claim 1 , wherein the pre-filter housing comprises one or more filters with an average pore size of about 1 to about 10 microns.
5. The apparatus of claim 1 , wherein the microfilter housing comprises one or more microfilters with an average pore size of about 0.2 to about 1 microns.
6. The apparatus of claim 1 , wherein the receiving jacketed process vessel is connected to a cold glycol system to maintain temperature of the receiving jacketed process vessel.
7. The apparatus of claim 1 , wherein the skim jacketed process vessel is connected to a cold glycol system to maintain temperature of the skim jacketed process vessel.
8. The apparatus of claim 1 , wherein the apparatus further comprises an ultra-filter housing for ultra-filtering the microfiltered human skim milk.
9. The apparatus of claim 1 , wherein the microfiltered human skim milk is recombined with a portion of the cream fraction to form an end product.
10. The apparatus of claim 9 , wherein the end product is a standardized 20 Cal/oz human milk composition, a standardized 24 Cal/oz human milk composition, or a human milk fortifier.
11. The apparatus of claim 9 , wherein the end product comprises about 20-70 mg/ml protein, about 35-85 mg/ml fat, and about 60-140 mg/ml carbohydrates.
12. The apparatus of claim 9 , wherein the end product comprises about 35-85 mg/ml protein, about 60-110 mg/ml fat, and about 60-140 mg/ml carbohydrates.
13. The apparatus of claim 1 , further comprising a vessel for recombining the microfiltered human skim milk with a portion of the cream fraction.
14. The apparatus of claim 1 , wherein the endospore forming bacteria is Bacillus cereus.