Food or edible material: processes – compositions – and products – Processes – Heating above ambient temperature
Patent
1998-01-16
1999-08-10
Yeung, George
Food or edible material: processes, compositions, and products
Processes
Heating above ambient temperature
99452, 426491, A23C 300
Patent
active
059356324
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a method for producing consumer milk with good keeping qualities.
BACKGROUND OF THE INVENTION
In order to secure that milk that is delivered to the consumers does not contain pathogenic microorganisms the milk is heat treated prior to the packaging. This heat treatment may be carried through at different time/-temperature combinations. Usual standards within this field are low pasteurization, high pasteurization and ultra pasteurization. Depending on the legislation in different countries the pasteurizing processes are different. As example of different processes there may be mentioned low pasteurization where the milk is heated to a temperature of 63-65.degree. C. and is kept at this temperature during 30 minutes or to 72-75.degree. C. with a holding time of 12-40 seconds. When high pasteurizing the treatment may comprise heating to 80-100.degree. C. during 10-20 seconds and at ultra pasteurization 110-125.degree. C. for 0.5-4 seconds.
A more forceful heat treatment gives a more complete killing of both pathogenic as other microorganisms present in the milk. The stronger the heat treatment the more pronounced is the effect on the chemical constituents, proteins, enzymes and vitamines in the milk which effect may be sensed as an impairment of the taste.
The shelf life of the packaged milk depends of course also on the treatment after the pasteurization step. It is extremely important to hinder reinfection during the process steps prior to the packaging in order to obtain good keeping qualities.
In order to obtain a milk product with a good keeping quality and a good taste one balances between the desire to achieve a product with as good bacteriological quality as possible, which product at the same time has not been effected negatively by the necessary heat treatment.
One way of obtaining a milk product with an extended shelf life is described in SE 451 791. According to this patent milk is divided into a cream and a skim milk fraction by means of centrifugal separation. The skim milk fraction is led to a microfilter and is divided into a permeate with a low bacteria content and a concentrate with a higher fat content than the permeate in the microfilter. The cream fraction and the concentrate are sterilized and remixed in desired proportions with the permeate after which the mixture passes a final heat treatment. The milk obtained according to the patent which is bacteria-poor may for example be used for producing cheese or be sold as consumer milk with extended shell life.
SUMMARY OF THE INVENTION
According to the invention there is now proposed a method of continuously producing a consumer milk with good keeping qualities where no part of the milk flow has been subjected to more than one heat treatment. In many countries the legislation forbids more than one heat treatment. According to the method of the invention a flow of skim milk is brought to pass a microfilter from which there is obtained a retentate flow and a permeate flow. The obtained permeate flow is subjected to a heat treatment and is then remixed with a partial flow of high temperature treated cream product in a desired amount in order to give a consumer milk with a long shelf life.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 illustrates a flow chart of a method of producing pasteurized consumer milk according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The method of the present invention comprises the steps of separating whole milk into a fraction of cream and a fraction of skim milk, passing a flow of the fraction of skim milk through a microfilter to obtain a flow of retentate and a flow of permeate, treating a flow of the cream fraction at a high temperature of at least 110.degree. C. for a predetermined time period sufficient to sterilize the cream fraction, remixing the high temperature-treated flow of cream with the permeate flow to form the consumer milk, and pasteurizing the permeate flow prior to remixing with the high temperature-treated cream flow. Th
REFERENCES:
patent: 3233964 (1966-02-01), Skoldberg
patent: 3973048 (1976-08-01), Sollerud
patent: 4515823 (1985-05-01), Kirschenmann
patent: 4560567 (1985-12-01), Rausing
patent: 4853246 (1989-08-01), Stevens
patent: 4876100 (1989-10-01), Holm et al.
patent: 4894243 (1990-01-01), Ahrne 426580
Tetra Laval Holdings & Finance S.A.
Yeung George
LandOfFree
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