BYPASSING CURD-WASH IN CONTINENTAL CHEESE MAKING

TITLE: Bypassing curd-wash in continental cheese making

FIELD OF THE INVENTION The present invention relates to novel methods and com positions for bypassing the cu rd- wash step in continental cheese making .

BACKGROUND ART

The typical cheese manufacturing process for making continental type cheese most often comprise :

1) Milk treatment: 72 °C/15sec, cooling to 31-33 °C

2) Culture addition and pre-ripening : 15-45min

3) Renneting : Add rennet, 31-33 °C, 25-40min

4) Cutting and Stirring : cut into 5- lOml cubes. Stir for l-25min

5) Washing : removal of a whey volume eq uivalent to 35-40% of initial milk volume.

Add 25-30% of initial milk volume as hot water.

6) Pre-press : 20min at 2-4 bar.

7) Molding and pressing : Pressing time from 30-90min at 0-6 bar.

8) Salting : e.g . by brining .

9) Storage

As known by the person skilled in the art, the process may be amended and adjusted beyond the temperature, time and volume intervals given above. An important parameter in the continental cheese is the final pH of the cheese. After salting (or brining), the pH value of the cheese must be above 5.15 and it must not decrease during the ripening stage and storage.

To control the final pH, and because the continental cheese production recipes uses mes- ophilic cultures, the traditional process requires a washing step (step 5) above to decrease the lactose content in the curd before the acidification . By that way, the acid ification stops when all the lactose is consumed and the final pH does not d rop below the desired value. The washing step as outlined in step 5) typically comprise :

- removal of a defined volume of whey (from 10 to 50%) - adding a defined volume of water (from 10 to 50%)

The quantities may depend on the type of cheese, and the lactose content in the milk which may vary with the season, the kind of cows, etc.

Removing whey and adding heated water as part of the washing step, impose several undesirable factors relating to water, energy and time consumption as well as e.g. yield-loss due to removal of dry matter. Furthermore the washing step requires a prolonged stay of the milk in the cheese vat thereby limiting the throughput in the cheese production line.

Because of the significant costs and drawbacks associated with the washing step, cheese makers have attempted to remove this step by various means.

However, removing the washing step in the production process imposes a number of risks related to:

- post-acidification

- undesirable taste / flavor development

- undesirable texture development

- proteolysis

- reduced shelf life

The most commonly used approach applied in attempt to bypass the washing step has been to use thermophilic cultures only. The rationale of using thermophilic cultures is the opportunity to stop the growth of the thermophilic cultures by lowering the temperature, according to the temperature profile of the cheese manufacturing process. However, using thermophilic cultures only has resulted in unsatisfactory proteolysis, undesirable flavor and shortened shelf life.

SUMMARY OF THE INVENTION

The problem to be solved by the present invention is to provide a method and compositions allowing production of continental cheese in a non-wash process.

The present inventors have found that by using a mesophilic culture with no or very limited post-acidification and with good pH-stabilization, optionally together with different bacterial strains of the genuses comprising : Lactococcus, Streptococcus, Diacetylactis and Lactobacillus, combined with a specific coagulant enzyme and by an adjustment of the production process, it is possible to bypass or minimize the washing step while obtaining the desired acidification, texture and taste of the produced cheese.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to a method for producing a continental type cheese, the method comprising providing a milk composition and subjecting said composition to a number of consecutive steps comprising :

1) Adding at least one mesophilic culture and optionally at least one thermophilic culture, and optionally at least one Lactobacillus helveticus cultures, optionally at least one Leuconostoc spp. culture and optionally at least one bioprotective culture

2) Optionally pre-ripening

3) Renneting

4) Cutting and Stirring

5) Washing

6) Optionally pre-pressing

7) Molding and pressing

8) Salting : e.g. by brining,

wherein water is added in an amount of less than 10% of the initial milk volume between step 4) and step 6).

The person skilled in the art will readily know that a method as outlined above may be amended and adjusted to ensure the desired result under the given circumstances. As example, step 1) may be preceded by heating the milk to around 72°C for 5-60secs and optionally cooling the milk to 31-33 °C.

In a preferred embodiment, the cheese obtained by the method of the present invention is characterized by having a moisture content of around 44%, such as e.g. 40%, 42%, 44%, 46%, 48% or 50% of moisture, a fat in dry matter content around 40%, such as e.g . 36%, 38%, 40%, 42% or 44% fat in dry matter content

and a total salt content of around 1.7%, such as e.g. 1.5%, 1.6%, 1.7%, 1.8%, 1.9% or 2.0%.

In a related aspect, the present invention relates to a composition comprising milk and at least one mesophilic culture, at least one thermophilic culture, optionally at least one Lac- tobacillus helveticus strain and optionally at least one Leuconostoc spp. strain and optionally at least one bioprotective strain and chymosin. In yet at related aspect, the present invention relates to the use of a composition comprising milk and at least one mesophilic culture, optionally at least one thermophilic culture, optionally at least one Lactobacillus helveticus and optionally at least one Leuconos- toe spp. and optionally at least one bioprotective culture and chymosin in a non-wash process for producing a continental type cheese.

The person skilled in the art will know what is meant by the terms and classifications as 'mesophilic culture', 'thermophilic culture', Lactobacillus helveticus, Leuconostoc and bio- protective strains or cultures. Hence for exemplification only, the terms are detailed below.

In present context, the at least one mesophilic culture is characterized in that it has a good capacity of pH stabilization at the needed final pH, and with a very low risk of post- acidification during the ripening stage. Often, but not always, mesophilic cultures can only withstand up to 30°C and are thus commonly used when the curds are not heated above that temperature such as when making Gouda and Cheddar.

The at least one mesophilic culture is not restricted to a specific bacterial species but may e.g. be a Lactococcus spp., Diacetylactis spp. or a Leuconostoc spp. Commercially available mesophilic cultures comprise e.g. M03 or C-904 from Chr. Hansen.

The at least one thermophilic culture is characterized in that it contributes to texture and also the consumption of lactose and the production of galactose. Commercially available examples of such thermophilic cultures are e.g. SCC-100 from Chr. Hansen.

The at least one Lactobacillus helveticus strain is characterized in that it contributes to the flavor of the ripened cheese and helps to stabilize the final pH. Commercially available examples of such Lactobacillus helveticus strain include e.g . LHB-01 from Chr. Hansen.

The at least one Leuconostoc strain contributes mainly to flavor development of the ripened cheese and is commercially available as e.g . FD-0133 from Chr. Hansen.

The at least one bioprotection strain or culture contributes to stabilize the pH and to pre- serve the cheese during the ripening and storage. Examples of commercially available bioprotective cultures is the BS range, including BS10, -20 and -30 from Chr. Hansen. The rennet added in step 3) is preferably a chymosin with low unspecific proteolysis such as e.g . camel chymosin or a variant thereof, bovine chymosin or a variant thereof. Preferably, the rennet has a higher C/P ratio than e.g. bovine chymosin and/or a lower β- cleavage than e.g. bovine chymosin. Commercially available examples of chymosins according to present invention include Maxiren, Maxiren XDS both from DSM and Chy-Max and preferably Chy-Max M from Chr. Hansen. Alternatively, the rennet may be a microbial coagulant, e.g. produced by Rhizomucor such as e.g. Rhizomucor miehei. Commercially available microbial coagulants include Hannilase® L and Hannilase® XP from Chr. Han- sen.

The method may further comprise a drying step between step 4) and 6) wherein the curd is dried before molding to reduce wet matter and control the moisture content of the cheese.

In yet a further related aspect, the continental type cheese is Edam, Gouda, Continental processed cheese and/or Maasdamer.

DEFINITIONS

All definitions of relevant terms are in accordance with what would be understood by the skilled person in relation to the herein relevant technical context.

The term "chymosin" relates to an enzyme of the EC 3.4.23.4 class. Chymosin has a high specificity and predominantly clots milk by cleavage of a single 105-Ser-Phe- | -Met-Ala- 108 bond in kappa-chain of casein. As a side-activity, chymosin also cleaves β-casein primarily between Leul92 and Tyrl93. The resulting peptide β(193-209) will be further degraded by proteases to short hydrophobic peptides that taste bitter. An alternative name of chymosin used in the art is rennin.

The term "chymosin activity" relates to chymosin activity of a chymosin enzyme as understood by the skilled person in the present context.

The skilled person knows how to determine herein relevant chymosin activity. As known in the art - the herein relevant so-called C/P ratio is determined by dividing the specific clotting activity (C) with the proteolytical activity (P). As known in the art - a hig her C/P ratio implies generally that the loss of protein during e.g . cheese manufacturing due to non-specific protein degradation is reduced, i.e. the yield of cheese is improved . The term "initial milk volume" means the volume of milk initially procured before commencing the method accord ing to the present invention, e.g . the total milk volume in a cheese vat before step 1 of the herein described method .

The term "mature polypeptide" means a peptide in its final form following translation and any post-translational modifications, such as N terminal processing, C terminal truncation, glycosylation, phosphorylation, etc. In the present context may a herein relevant mature chymosin polypeptide be seen as the active chymosin polypeptide sequence - i.e. without the pre-part and/or pro-part sequences. Herein relevant examples of a mature polypeptide are e.g . the mature polypeptide of SEQ ID NO : 1 (bovine chymosin), which is from amino acid position 59 to amino acid position 381 of SEQ ID NO : 1 or the mature polypeptide of SEQ ID NO : 2 (camel chymosin), which is from amino acid position 59 to amino acid position 381 of SEQ ID NO : 2.

The term "non-wash process" means a process for making continental cheese, wherein water is added in a volume less than 10%, such as e.g . 7%, 5%, 3%, 1% or 0% of the initial milk volume during the washing step in the cheese making process.

The term "parent" or "parent polypeptide" means a polypeptide to which an alteration is made to produce the enzyme variants of the present invention . The parent may be a nat- urally occurring (wild-type) polypeptide or a variant thereof.

The term "thermophilic culture" means a culture which can most typically withstand temperatures up to 50 °C and thus are commonly used when the curds are not heated above that temperature such as when making Swiss or harder Italian cheeses.

The term "variant" means a peptide having chymosin activity comprising an alteration, i.e. , a substitution, insertion, and/or deletion, at one or more (several) positions. A substitution means a replacement of an amino acid occupying a position with a different amino acid ; a deletion means removal of an amino acid occupying a position ; and an inser- tion means adding 1-3 amino acids adjacent to an amino acid occupying a position . The amino acid may be natural or unnatural amino acids - for instance, substitution with e.g . a particularly D-isomers (or D-forms) of e.g . D-alanine could theoretically be possible. The term "wild-type" chymosin peptide means a chymosin expressed by a naturally occurring organism, such as a mammalian (e.g . camel or bovine) found in nature.

Preferred embodiments of present invention are summarized in the following related items :

Item 1. A method for producing a continental type cheese, the method comprising providing a m ilk com position and subjecting said com position to a number of consecutive steps comprising :

1) Adding at least one mesophilic cultures and optionally at least one thermophilic cultures, and optionally at least one Lactobacillus helveticus cultures, optionally at least one Leuconostoc spp. cultures and optionally at least one bioprotective culture

2) Optionally pre-ripening

3) Renneting

4) Cutting and Stirring

5) Washing the milk composition

6) Optionally pre-pressing the milk composition

7) Molding and pressing

8) Salting : e.g . by brining,

wherein water is added in an amount of less than 10% of the initial milk volume between step 4) and step 6).

Item 2. A method accord ing to item 1, wherein step 1) is preceded by heating the m ilk to around 72 °C for 5-60secs and/or cooling the milk to 31-33 °C. Item 3. A method accord ing to item 1 or 2 wherein the at least one mesophilic culture is M03 from Chr. Hansen .

Item 4. A method accord ing to any of the preced ing items, wherein the at least one thermophilic culture is SCC- 100 from Chr. Hansen . Item 5. A method according to any of the preceding items, wherein the at least one Lactobacillus helveticus strain is LH B-01 from Chr. Hansen .

Item 6. A method accord ing to any of the preced ing items wherein the at least one Leu- conostoc strain is FD-0133 from Chr. Hansen .

Item 7. A method accord ing to any of the preced ing items wherein the bioprotective cultures is selected from the Chr. Hansen BS range such as e.g . BS 10, BS20, BS30 and/or BS40.

Item 8. A method accord ing to any of the preced ing items wherein the rennet applied in step 3) is chymosin with low unspecific proteolysis such as e.g . camel chymosin or a variant thereof or bovine chymosin or a variant thereof. Item 9. A method accord ing to any of the preced ing items wherein further comprising a drying step between step 4) and 6) wherein the curd is dried before molding to reduce wet matter and control the moisture content of the cheese.

Item 10. The method accord ing to any of the preced ing items wherein the continental type cheese is Edam, Gouda, Continental processed cheese and/or Maasdamer.

Item 11. A com position comprising m ilk and at least one mesophilic culture, at least one thermophilic culture, at least one Lactobacillus helveticus strains and at least one Leuco- nostoc spp. strain and optionally at least one bioprotective strain and a chymosin .

Item 12. A composition according to item 11, wherein the at least one mesoph ilic culture is M03 from Chr. Hansen .

Item 13. A composition according to item 11 or 12, wherein the at least one thermophilic culture is SCC- 100 from Chr. Hansen .

Item 14. A composition accord ing to any of items 12 to 13, wherein the at least one Lactobacillus helveticus strain is LH B-01 from Chr. Hansen . Item 15. A composition according to any of items 12 to 14, wherein the at least one Leu- conostoc strain is FD-0133 from Chr. Hansen . Item 16. A composition accord ing to any of items 12 to 15 wherein the bioprotective strain or culture is selected from the Chr. Hansen BS range such as e.g . BS 10, BS20 and/or BS30.

Item 17. A composition accord ing to any of items 12 to 16 wherein the rennet applied in step 3) is a chymosin with low unspecific proteolysis such as e.g . camel chymosin or a variant thereof, or bovine chymosin or a variant thereof. Item 18. A composition accord ing to any of items 12 to 17, wherein the composition is used in a method according to any of items 1- 11.

Item 19. Use of a mesophilic culture and optionally at least one thermophilic culture, and optionally at least one Lactobacillus helveticus culture, optionally at least one Leuconostoc spp. culture and optionally at least one bioprotective culture in a process comprising the following steps :

1) Adding said one or more culture

2) Optionally pre-ripening

3) Renneting

4) Cutting and Stirring

5) Washing the milk composition

6) Optionally pre-pressing the milk composition

7) Molding and pressing

8) Salting : e.g . by brining,

wherein water is added in an amount of less than 10% of the initial milk volume between step 4) and step 6).

DRAWINGS

Figure 1 : Schematic overview of the typical cheese manufacturing process for making continental cheese.

Figure 2 : Schematic overview of the continental cheese process without curd washing EXAMPLES

Example 1: Conventional continental cheese making process 1: Milk treatment (Fat - Protein - pH standardization, Pasteurization, Cooling) 2: Culture addition (pre-ripening 5 to 60 minutes)

3: Renneting (temperature 30 to 35°C, total coagulation: 12 to 40 minutes)

4: Cutting (grain curd size 27 to 343 mm3)

5: Stirring (10 to 25 minutes)

6: Whey removed (20 to 50 % of total volume)

7: Water adding (10 to 50 % of total volume, 35 to 50°C)

8: Stirring + scalding (20 to 60 minutes, final temperature 36 to 43°C)

9: Whey removed (facultative)

10: Draining + Molding

- Draining + pre-pressing 20 minutes + curd cutting + molding

- Draining in perforated tubes + cutting + molding

11: Pressing - Acidification (40 to 120 minutes)

12: Demolding

13: Salt brine (depend of the cheese size)

14: Storage - Ripening (6 to 20°C, 5 to 52 weeks)

Example 2: Continental cheese making process with no curd washing

1: Milk treatment (Fat - Protein - pH standardization, Pasteurization, Cooling)

2: Culture addition (pre-ripening 5 to 60 minutes)

3: Renneting (temperature 30 to 35°C, total coagulation: 12 to 40 minutes)

4: Cutting (grain curd size 8 to 125 or 343 mm3)

5: Stirring (10 minutes)

6: Whey removed (20 to 30 % of total volume)

7: Stirring + scalding (40 to 60 minutes, final temperature 36 to 43°C)

8: Whey removed (facultative)

9: Draining + Molding

- Draining + pre-pressing 20 minutes + curd cutting + molding

- Draining in perforated tubes + cutting + molding

10: Pressing - Acidification (40 to 120 minutes)

11: Demolding

12: Salt brine (depend of the cheese size)

13: Storage - Ripening (6 to 20°C, 5 to 52 weeks) Example 3: Production of continental cheese (German Gouda) with and without curd washing. 8 different compositions and processes were applied to produce GOUDA with no curd washing .

The target cheese composition is 44% of moisture, 40% of fat in dry matter and 1.7% of total salt. The pH values of the cheese with the traditional process are 5.85 before brining, 5.30 after brining and more than 5.65 after 75 days of ripening and storage.

The ingredients of the 8 different cheeses are outlined in table 1 below. Different blends of rennets and cultures were used in order to determine the optimal conditions for making a continental cheese without washing the curd.

As outlined in tables 1 and 2 below, batch 45-3-4 is included as control including a washing step, whereas batches 45-3-5, 45-3-6, 45-3-7, 45-4-4, 45-4-5, 45-4-6 and 45-

4-7 are non-washing processes according to the present invention.

Table 1 (above) - ingredients

Maturation starting Add culture time 08:00 08:30 09:00 09:30 08:00 08:30 09:00 09:30

Duration 00:35 0035 00:35 00:37 00:35 00:35 00:33 00:35

Renneting Add rennet time 08:35 0905 09:35 10:07 08:35 09:05 09:33 10:05

Temperature 32°C 32°C 32°C 32°C 32°C 32°C 32°C 32°C

Cutting Time 09:09 0931 10:07 10:36 09:03 09:35 10:05 10:35

Grain size 5 mm 5 mm 5 mm 5 mm 5 mm 5 mm 5 mm 5 mm

Stirring Time 09:12 0934 10:11 10:39 09:08 09:38 10:10 10:40

Speed 386 235 / 300 235 / 300 235 / 300 235 / 300 235 / 300 235 / 300 235 / 300

Duration 00:20 00:50 00:50 00:50 00:50 00:45 00:45 00:45

Whey off Time 09:32 1024 11:01 11:29 09:58 10:23 10:55 11:25

Quantity 75 kg 45 kg 45 kg 45 kg 45 kg 45 kg 45 kg 45 kg

Water adjunct Time 09:37

Quantity 18kg 56°C

Stirring / scalding Scalding start time 09:37 09:44 10:21 10:49 09:18 09:48 10:20 10:50

Scalding end time 10:02 1025 11:01 11:29 09:53 10:23 10:55 11:25

Duration 00:25 00:41 00:40 00:40 00:35 00:35 00:35 00:35 final temperature 37°C 37°C 37°C 37°C 37°C 37°C 37°C 37°C

END Empying start 10:32 10:49 11:21 11:49 10:28 10:58 11:30 12:00

Total stirring 01:20 01:15 01:10 01:10 01:20 01:20 01:20 01:20

Total time in vat before emptying 02:32 02:19 02:21 02:19 02:28 02:28 02:30 02:30

Table 2 (above) - processes

The speed of stirring for the control batch (45-3-4) is 386. For the trial vats, it starts at 235 and goes up to 300 after 3 - 4 minutes. The duration of total stirring is similar in the control vat and in the 4 trial vats; it is a little bit shorter in the other vats. The final temperature is the same in all the vats.

After stirring and scalding, the cheeses were brined and ripened under storage conditions according to table 3 below.

Table 3 (above) - Brining and ripening cond Example 4 - Results 22,63 21,86 21,37 22,03 21,66 21,66 22,03 21,70

45,40 46,21 47,02 45,82 46,27 46,22 45,79 46,42

1,42 1,56 1,63 1,56 1,85 2,07 1,69 1,72

58,68 59,13 59,80 58,76 59,06 58,99 58,72 59,28

3,13 3,39 3,46 3,42 3,98 4,48 3,69 3,69

0,1 <LOD <LOD 0,1 <LOD <LOD <LOD <LOD

0,09 2,69 2,61 1,95 1,06 0,68 0,47 1,00

<LOD <LOD <LOD <LOD <LOD <LOD <LOD <LOD

1,7 0,1 0,2 1,2 0,7 0,9 0,9 0,9

13,7 14,0 12,8 13,8 15,1 15,9 16,0 15,3

<LOD 0,7 0,7 0,4 0,5 0,4 0,4 0,5

<LOD <LOD <LOD <LOD <LOD <LOD <LOD <LOD

<LOD <LOD <LOD <LOD <LOD <LOD <LOD <LOD

CONTROL

Table 4 - Cheese composition.

As shown in table 4 above, the cheeses with and without curd washing are acceptably close to the target cheese profile of around 44% of moisture, around 40% of fat in dry matter and around 1.7% of salt.

Table 5 - Yield results

Compared to the control batch, the non-washing process entails an average yield increase of 3.09% when compared to the conventional process in which the curd is washed by whey removal and addition of water.