LU79982A1 - IMPROVEMENT IN THE MANUFACTURING PROCESS OF CONCENTRATED SKIMMED MILK FROM WHOLE MILK - Google Patents

Description

<Γ D. 4ο.972

Ml - GRAND DUCHY OF LUXEMBOURG

..... 0 ....... Q 0 £ · rfTf ^ hrïk ,, ·, «...

at ................................................. ................ Mr. Minister '„of the National Economy and the Middle Classes

I Title issued: ........................................ "K

j Industrial Property Service

5¾¾ LUXEMBOURG

Patent Application I. Application

The so-called company: LAGUILHARRE SA, 2o-22, rue d'Arras, f ................................. .................................................. .................................................. .................................................. .................................................. ......-....................................... (1) j at 92ooo NANTERRE, France, represented by Mr. Jacques j de Muyser, acting as agent __ (2) i "j * rtônnsp po fourteen July 19oo seventy-eight ^ j 15 ......... ce .................................................. .................................................. .................................................. .................................................. ...

at ................................ hours, at the Ministry of National Economy and the Middle Classes, in Luxembourg: 1. the present request for obtaining a patent for the invention concerned: ^ "T" Improvement of the skimmed milk manufacturing process (4) * concentrated from whole milk ".

declares, assuming responsibility for this declaration, that the inventor (s) is (are): ......................... .................................................. .................................................. .................................................. .................................................. .......................... I ....................... .... (5) ..................... „" "......... Ö ......... .........- Z - T NANTERRE ........... July 13, 1978 2. the delegation of power, dated ............. .................................................. ......... on ................. z ...................... .............................

3. description in language .......................................... of the invention in two copies; 4 ......... Q ................... drawing boards, in two copies; 5. the receipt of the taxes paid to the Luxembourg Registration Office, on ... July 14 ..... ..... 1978 ................. .................................................. .................................................. .................................................. ......................... ...

claims for the above patent application the priority of one (s) request (s) of (6) ........................... ........................: ......................... ................... filed in (7) ....................... .................................................. .................................................. ............

the ................................................. .................................................. .................................................. .................................................. ...... ............................................ ............... (8) in the name of ............................. .................................................. .................................................. .................................................. .................................................. ................. (9) elect domicile for him / her and, if appointed, for their proxy, in Luxembourg ............ ............................

. ; .35, bld. noyai _ (10d requests the grant of a patent for the invention for the subject described and represented in the appendices - above-mentioned, - with postponement of this grant to ................ ................................month.

• ‘II. Deposit Minutes; The above application for a patent for invention has been filed with the Ministry of National Economy and the Middle Classes, Industrial Property Service in Luxembourg, on: July 14, 1978 .. · '.....' ·· · .. Pr. The Minister at ........ 15 ................ hours / \ of the National Economy and the Middle Classes; ; P · d · β j; Γ / ï -x: A 65007/1 ^ ΆΤ / Λγν "name ίΐν ·" τΛα orlrncra _ / 9 \ e’ïl xr a lî.-in wt-cnféi-Âi-v * A. .. .-. v "" ·: t / -. 74 + A λ / <s \ D. 4ο.972> Brief Description submitted in support of a request for

PATENT

at

Luxembourg formed by: LAGUILHARRE S.A.

for: "Improvement of the manufacturing process for skimmed milk concentrated from whole milk".

i ♦ / d 1 * 1

The present.iivention relates to an improved process for the manufacture of concentrated skim milk from whole milk, this skim and concentrated milk then being intended in particular for the preparation of powdered milk by drying.

In order to prepare concentrated skim milk, it is known to carry out the following operations in series: preheating cold whole milk, skimming whole milk thus preheated and concentrating the resulting skim milk. However, this process has the disadvantage of requiring a high capacity cream separator.

In order to recover the fatty matter contained in cheese serum, it is known to skim this concentrated serum, this skimming operation being able, because of the reduction in volume, to be carried out in a low capacity machine. This process is however very difficult to apply to whole milk since whole milk having undergone the prior concentration up to a concentration suitable for example for the production of powdered milk by drying, is generally too viscous to be skimmed so satisfactory.

It is also known that during skimming, the mechanical action produces, by friction and pressure exerted on said product, a release of oleic acid which is the cause of rapid rancidity of the butters, this phenomenon being all the more important as the milk is richer in lipase. It therefore appears necessary to destroy this lipase and this result is obtained by heating to at least 70 ° C. It follows that before skimming the whole milk, it must be brought to at least 70 ° C.

However, in order to eliminate all the drawbacks of the known methods and to overcome the difficulty constituted by said release of oleic acid during skimming, the present invention relates to a new method of "manufacturing concentrated skim milk which is characterized in that it consists in carrying out in series, the concentration of the whole milk in at least one evaporation body of an evaporator possibly with multiple effects and the creaming of the whole milk thus preconcentrated, the whole milk undergoing before skimming and at any stage of its concentration, a heat treatment at a temperature at least equal to J0 ° C and the concentration of the skimmed milk thus resulting being then optionally continued in at least one other evaporation body of said evaporator.

Since the whole milk is partially concentrated before the skimming operation, the capacity of the skimmer can be significantly reduced. In addition, this concentration being only partial, the viscosity of the milk to be skimmed remains unimportant and the skimming operation can be carried out under good conditions, the concentration of the resulting skimmed milk can then be brought to value! 0 desired.

v. 2 \

According to a variant, one of the evaporation bodies has before the skimmer is constituted by one of the two evaporation bodies of lower capacity resulting from the division of an effect of the evaporator in such a way evaporation obtained before skimming is such that the flow rate of the preconcentrated whole milk obtained 5 corresponds to that of the skimmer, the concentration of the skimmed milk being continued in the second of these two evaporation bodies, before or after passage in the possible effects remaining. Thus, if the flow rate of the skimmer is higher than that of the preconcentrated whole milk from the effect or effects of the evaporator. preceding the separator, it becomes possible by this particular arrangement • jq to adjust the flow rate of whole milk to that of the separator.

‘. Preconcentrated whole milk to be skimmed can possibly be cooled before the skimming operation. In fact, it has been observed that if skimming is carried out on milk with a temperature of J0 ° C or higher, there is a risk of fouling of the cream separator. It is therefore recommended to reduce the temperature of the milk to be skimmed to a temperature below 70 ° C but preferably above k5 ° C.

Advantageously, this cooling is obtained by heat exchange between said preconcentrated whole milk and the cold starting whole milk.

According to another variant, the milk leaving the skimmer is reheated until it reaches a temperature at least equal to the operating temperature of the evaporation body in which its concentration is continued. It may indeed happen that the cream separator is at a temperature lower than that of the evaporation body in which the concentration of skim milk will continue.

It is therefore recommended to raise the temperature of the skimmed milk. This reheating can be carried out by any means, for example using sampling steam.

Advantageously, the reheating can also be obtained by heat exchange between said milk leaving the separator and the whole milk which has just undergone the heat treatment at a temperature at least equal to 70 ° C.

It should be noted that the preconcentrated whole milk to be skimmed can be subjected to vacuum expansion in a relaxation box. This operation will have the effect of lowering the temperature of the milk undergoing this expansion. The immediate advantage is the limitation or even the elimination of fouling of the cream separator depending on the importance of the trigger.

The expansion box can in particular be in relation to one of the evaporation bodies placed after the cream separator, the milk then being able to be cooled until it reaches the operating temperature of this evaporation body.

Advantageously, means are provided for regulating the importance of the trigger.

According to yet another variant, the heating body of the evaporation body preceding the cream separator is provided with an auxiliary steam source, in particular a thermocompressor. This arrangement is particularly advantageous for the IfO in the case of a thermocompression multiple-effect evaporator where the recompression 3 of steam takes place on at least two effects in series, the auxiliary supply of steam taking place on one of the effects traversed by · whole milk. Putting this auxiliary source into operation or stopping, or even adjusting the quantity of steam supplied by this source, in fact allows an easy adjustment of the whole milk flow rate to that of the de-stemming machine.

In all the embodiments and variants described above, the whole starting milk can be preheated before concentration. Advantageously, this preheating is carried out using sampling steam on all or part of the effects of the evaporator.

Various embodiments of the present invention are shown below, by way of examples, with reference to the appended drawing in which: FIG. 1 is the diagram of an installation allowing the implementation of the claimed process and in which the de-stemming machine follows the first effect of a four-effect evaporator, this first effect receiving the whole milk to be concentrated and skimmed, FIG. 2 is the diagram of an installation enabling the process to be carried out claimed and which provides for the cooling of the preconcentrated milk before skimming, - Figure 3 is the diagram of an installation allowing the implementation of the process claimed and which provides for an expansion of the preconcentrated milk before its skimming, - Figure b is the diagram of an installation allowing the implementation of the claimed process and which provides an auxiliary source of steam on the heating body of the first effect, FIG. 5 is the diagram of an installation allowing the implementation using the claimed process and in which the de-stemming machine follows the second effect of a four-effect evaporator, this second effect receiving the whole milk to be concentrated and skimmed, and - Figure 6 is a diagram of an installation allowing the implementation of the claimed process and in which the de-stemming machine follows the first of the two evaporation bodies resulting from the division of an effect into two evaporation bodies of lower capacity.

-The installation -represented in -figure -1 comprises a falling evaporator with four effects 1,2,3, ^ -, the first of these effects being-supplied, by a pipe 5, with whole milk having -subi- a treatment at a temperature higher than • 70 ° G in a heater 6-, the latter being itself supplied with whole milk ”a; *. h circulated in series through preheaters 7 to 11. The whole milk thus undergoes a first concentration in effect 1, the resulting milk coming from the base of this effect being directed by a line 12 towards a cream separator 13. The milk obtained skim is then sent by a line 1¼ at the head of the second effect 2, 5 the resulting concentrated skim milk being brought by a line 15 at the head of the third effect 3. It is then drawn off at the base of this effect 3 and directed by a line 16 at the head of the last effect U, the concentrated skim milk eliminated at the base of the effect k being brought by a line 17 to its place of use (drying, transport not shown). The vapor generated in the 10 effects 1 , 2 and 3 pass respectively through the separators 18, 19 and 20 and from there • is brought respectively through the lines 21, 22 and 23, into the heating body of the following effect. Finally, the vapor generated in effect k passes through the separator 2k of this effect and from there is supplied via line 25 to a condenser, not shown. A fraction of the steam escaping from the separator 18 is recompressed in a thermocompressor 26 then sent by a line 27 to the heating element of effect 1. The line 27 carries a bypass line 28 intended to supply steam to the preheater 7 · Finally, the lines 21, 22, 23 and 25 carry bypass respectively lines 29, 30, 31 and 32 supplying steam respectively to the preheaters 8, 9, 20 10 and 11.

The installations according to FIGS. 2 to 6 substantially comprise the same elements as the installation in FIG. 1 and these same elements will be designated by the same reference.

The essential difference between the installations of FIGS. 1 and 2 is that in the case of FIG. 2, a heat exchanger 33 is arranged in series between the effect 1 and the cream separator 13 · In the case of FIG. 2 considered , milk: whole preheated to 50 ° C in the preheaters 10 and 11 is brought into the heat exchanger 33 by a line 3k. At the outlet of this exchanger, this whole milk is at 58 ° C. from which it is directed, via a pipe 35 towards the inlet of the preheater 8 from where it passes to the preheater 7 and its path then becomes identical to that of FIG. 1, except that at the outlet of effect 1, where it is at 67 ° C., and before entering the cream separator 13 / it crosses the exchanger 33 from where it comes out at 55 ° C.

It is quite certain that it is perfectly possible to use, in the exchanger 33, a different cooling fluid than the whole milk to concentrate and to skim. Finally, it should also be noted that in the installation of FIG. 2, the preheater 9 and the pipe 30 have been eliminated.

- The essential difference between the installations of FIGS. 1 and 3 lies in the fact that, in accordance with FIG. 3, an expansion box 36 is 1 * 0 arranged on the path of the pipe 12. This expansion box is in ^. 5 relationship, via a conduit 37> with a vacuum source not shown. This conduit 37 could also be related to any of the effects 2, 3-or H of the evaporator, the expansion box 36 and therefore, the milk which circulates therein, then being at the temperature prevailing respectively in these effects.

5 Thanks to this arrangement, skimming can therefore be carried out at a temperature lower than that of effect 1. The duct 37 advantageously carries a regulator 38 which makes it possible to adjust the vacuum in the expansion box 3o. The total closure of the conduit 37 by this regulator corresponds to zero expansion in the body 3o, that is to say a reduction in temperature zero relative to the temperature of effect 1.

The installation according to FIG. 1 differs from that of FIG. 1 by the fact that the thermocompressor 26 recompresses a fraction of the vapor escaping from the separator 19 and no longer that escaping from the separator 18, and by the fact that an auxiliary thermocompressor 26 'recompresses, if necessary, 15 of it, a fraction of the steam escaping from the separator 18. Thus, if for one reason or another, the flow rate of preconcentrated whole milk from effect 1 is greater to that of the cream separator 139 the auxiliary thermocompressor 26 * is started, from which there results a greater evaporation in effect 1, and consequently, a lower flow rate of whole milk at the outlet of this effect 1. the means 20 therefore makes it possible to compensate for variations in the flow rate of whole milk without having to modify the cream separator.

In the installation of FIG. 5 »the thermocompressor 26 recompresses part of the steam escaping through the separator 19 and not that escaping through the separator 18. Furthermore, the whole milk to be concentrated and 25 having undergone treatment at a temperature of at least 70 ° C. is no longer sent at the head of effect 1, but at the head of effect 2. However, before entering this effect 2 it passes through a heat exchanger 39 where it undergoes cooling to 62 ° C. The whole milk preconcentrated at 62 ° C and resulting from effect 2 is sent via a line 15 ′ into the cream separator 13- The skimmed milk 30 thus obtained is then directed, by a conduit il · ', towards said heat exchanger 39 where its temperature is brought up to 67 ° C by exchange with whole milk at 75 ° C which also circulates there. From there, it is sent at the top of »v effect 1 which is at 67 ° C. The preconcentrated skim milk leaving this effect 1 is then directed, via line 12 ′, to the top of effect 3S after which the milk flow is the same as in the case of FIG. 1.

In the case of FIG. 6, the whole milk having undergone the heat treatment at a temperature higher than 70 ° C. arrives, via the line 5 "at the head of effect 1. The whole milk preconcentrated in this effect 1 is then sent , via a 12 ”line, at the head of an evaporation body 2 'resulting from lK) the division into two evaporation bodies 2' and 2" with a lower capacity of 6 to effect 2. The milk from de.ce body 2 'is sent by a line into the creamer 13, the resulting skimmed milk then being directed by a line M at the head of the evaporation body 2 ". Finally, the milk from the base of this body 2 "is brought in via a pipe 15" at the head of the effect 3 "after which 5 the milk flow is the same as in the case of FIG. compressor 26 no longer recompresses part of the steam coming from the separator 18, but part of the steam coming from the separators 19 'and 19 "from the evaporation bodies 2' and 2" respectively. In the event that the dehit of the cream separator 13 is greater than that of the milk leaving effect 2, it becomes possible by simply dividing this effect 2 into two bodies 2 ′ and 2 ″ to adjust the dehit of this milk to that of the cream separator.

It is quite certain that it is possible, without modifying the spirit of the invention, to replace in the installations described above, the thermocompressor 26, and / or 26 ′ by a source of steam of another type (by simple example 15 steam inlet) and / or supply all or part of the preheaters 7 to 11 with steam coming from a source other than the effects of the evaporator.

Likewise, and depending on the desired concentration level of the skimmed milk, it is possible to use an evaporator having more or less than four effects.

It will also be noted that in the installations according to FIGS. 1 to 3, the thermocompression can be carried out as well on two or more effects in series as in the case of FIGS. 1 to 6.

In addition, whole milk which is not yet concentrated may enter into another effect than effects 1 and 2, the heat treatment always being carried out either on the milk which is not yet concentrated or on the preconcentrated milk but in any case before skimming. .

The invention also applies to the case of an evaporator comprising a mechanical vapor recompressor.

s.

V

Claims (8)

1. Process for the manufacture of skimmed milk concentrated from whole milk, characterized in that it consists in carrying out in series, the concentration of whole milk in at least one evaporation body of an evaporator possibly with multiple effects and l skimming of the whole milk thus preconcentrated, the whole milk undergoing before skimming and at any stage of its concentration a heat treatment at a temperature at least equal to 70 ° C. and the concentration of the skimmed milk thus resulting is then optionally continued in the at least one other evaporation body of said evaporator. 2. Method according to claim 1, characterized in that one of l _ 10 evaporation body disposed before the cream separator is constituted by one of two evaporation bodies of lower capacity resulting from the division of an effect of the evaporator in such a way that the evaporation obtained before skimming is * such that the flow of preconcentrated whole milk obtained corresponds to that of the skimmer, the concentration of skimmed milk being continued in the second of these two bodies evaporation, before or after passing through any remaining effects. ‘.. 20 3- A method according to any one of claims 1 and 2, characterized in that the pre-concentrated whole milk to be skimmed is cooled before this skimming operationi h. Method according to claim 3? characterized in that the cooling is obtained by heat exchange between said preconcentrated whole milk and the cold starting whole milk. 5 · Method according to claim 1, characterized in that the milk • leaving the creamer undergoes heating until reaching a temperature at least equal to the operating temperature of the evaporation body in which is continued its concentration. 6. Method according to claim 5, characterized in that the reheating is obtained by heat exchange between said milk leaving the creamer and the whole milk which has just undergone the heat treatment at a temperature of | less equal to J0 ° C. 7. Method according to any one of claims 1 to characterized I 35 in that the preconcentrated whole milk to be skimmed is subjected to expansion under vacuum in a relaxation box. 8. Method according to claim J, characterized in that said expansion box j is in relation with one of the evaporation bodies arranged after ij the cream separator. ]) +0 9 · Method according to any one of Claims 7 and 8, characterized 8 h1 10 · Method according to any one of the preceding claims, characterized in that the heating body of the evaporation body preceding the skimmer is equipped with an auxiliary source of steam, in particular a sweat thermocompres. 11. Method according to any one of the preceding claims, 5 characterized in that the whole starting milk is preheated before concentration. 12. Method according to claim 11, characterized in that the preheating is carried out using sample steam on all or part of the effects of the evaporator. * · T ·%