WO2005067726A1

WO2005067726A1 - Cheese wax

Info

Publication number: WO2005067726A1
Application number: PCT/EP2005/000121
Authority: WO
Inventors: Angela Leonarda Maria Smits; Jacobus Groot De
Original assignee: Dsm Ip Assets B.V.
Priority date: 2004-01-06
Filing date: 2005-01-06
Publication date: 2005-07-28
Also published as: EP1703799A1

Abstract

The present invention describes a wax comprising 0.05 to 28% (w/w) of poly (ethylene vinylacetate) (EVA), suitable for use in coating cheese. Coating hard, semi-hard or soft cheeses can protect the cheese from, for example, physical damage, loss of moisture or fungal infection. Use of wax comprising EVA improves the attachment of the wax layer to another layer, for example to the cheese surface itself or to an inner/first layer coating the cheese. Methods are provided for coating cheese or further coating an inner/first layer coating the cheese with wax comprising EVA.

Description

CHEESE WAX Field of the invention

After ripening or after moulding and pressing, cheeses are coated to prevent physical damage, to maintain a desired shape, to prevent loss of moisture or to protect against undesired fungi including yeasts and bacteria. Hard, semi-hard or soft cheeses can be protected by a coating. In general, monolayer or multilayer films can be used as coating. A multilayer that protects cheese may consist of a plastic or polymer coating (for example a copolymer based on polyvinyl acetate or a bio-polymer based on a protein base), and a second outerlayer of wax (for example based on paraffin). Wax can also be applied directly to bare or uncoated cheese. In general the wax layer will only be applied after ripening of the cheese. For example the wax layer is added after 4 weeks of ripening of young cheese. Cheeses are known to be respiring foodstuffs that produce gas, particularly CO₂. A problem that often is present with multilayer coatings is that the two layers do not entirely fix or adhere to each other, and accumulation of gas may occur between the two layers. Due to the presence of gas between the layers visual or physical damage on the cheese increases. According to the present invention, addition of poly (ethylene vinylacetate) (EVA) to wax improves the attachment of a wax layer to another layer. EVA is a copolymer of ethylene and vinylacetate. Use of EVA can prevent gas bubble formation between the two layers. Preferably the wax of the invention is applied on a plastic or polymer coating. More preferably this coating comprises polyvinyl acetate. According to the present invention 0.05 to 28%, preferably 0.1 to 15%, and more preferably 1 to 7% w/w of EVA is added to the wax before the wax is used as a coating on a respiring foodstuff such as cheese. The amount of EVA used in the wax is chosen in such a way that all the EVA is dissolved in the wax (saturation) and therefore this amount will be lower than the concentration at which EVA is not completely dissolved due to phase separation. EVA used in this wax may partly comprise another co- monomer, preferably an olefin like isobutylene or propylene. Preferably 20% or less of the ethylene, more preferably 10% or less of the ethylene and most preferably 5% or less of the ethylene of EVA is replaced by another olefin, for example isobutylene or propylene. Typically, the wax according to the invention is a blend of fully refined food grade hydrocarbon waxes or paraffin's. Preferably, the wax comprises at least 50% (w/w) refined solid wax, petrolatum and/or microcrystalline wax. In general the wax can be a blend of formulated linear and branched hydrocarbon waxes and optionally contains small amounts of polymers such as polyethylene, polyisobutene or butylrubber. The formulation is chosen for the optimal desired protection. A variety of cheeses are produced all over the world ranging from soft to hard and from old to young cheeses. Therefore a broad range of waxes is available nowadays for cheeses. The coloured grade waxes may also contain food grade colour pigments or dyes. The wax is melted before use and can be applied directly to the cheese surface, to cheese rind or to a waxed/bandaged surface of suitable integrity. Individual cheeses are immersed in molten wax for pre-set times, or sprayed or showered with molten wax for pre-set times. Wax layer thickness can be increased by using several immersions but can also be regulated via varying the waxing temperature or by selection of a suitable mixture of paraffin's. ^"Application of the wax can be manual, semi-automatic or automatic depending on the number of cheeses to be treated. Specialised waxing machines are commercially available. Machine settings can be modified in an empirical way in order to produce a specific end result in terms of wax application. Molten waxes used in the present invention are typically in the temperature range of 75 - 110°C. Typically, the congealing point (measured according to ASTM 938) of the wax ^"will be between 45 and 80°C, preferably between 50 and 70°C. Typically, the wax will have a viscosity, which when added to cheese, allows a uniform coating to take place. The viscosity should not be too low; otherwise the coating will be too thin. However, a high viscosity may result in too thick a coating or non-uniform coatings. The viscosity of the wax at 100°C (ASTM 3236) is preferably between 3 and 25 mPa.s, more preferably between 4 and 18 mPa.s. In order to prepare a homogeneous product and to allow a regular and even distribution of the wax, it is required to individually set treatment schemes for each kind of cheese. Softeners can be used to improve the physical properties of a cheese wax. However softeners are suspected to migrate from the wax into the cheese. Therefore there is a need to improve cheese waxes without using softeners or with very limited amounts of softeners. Preferably the wax contains less than 10% (w/w) of softeners or plasticisers, more preferably less than 1% (w/w). Preferably the wax is free of softeners or plasticisers. Preferably the wax contains less than 10% w/w of softeners or plasticisers on basis of butadiene. More preferably softeners comprising butadiene are excluded from the wax. Preferably the wax does not contain more than 0.001% w/w of an antioxidant(s).

EXAMPLES

Example 1 In the following experiment the positive effect of EVA on cheese wax adhesion to the coated cheese surface was demonstrated. Cheese wax, Paradip^® Natural 3517 acquired from Paramelt B.V. (The Netherlands), was melted in two separate pans, each containing approx. 11 kg cheese wax. In one of the two pans 4.5 wt% EVA, Escorene® 02528 containing 28 wt% Vinyl acetate acquired from Exxon Chemical, was mixed with the molten cheese wax to form a homogeneous liquid. Semi-hard PVA-coated Amsterdammer-type cheese wheels of approx. 4.5 kg were dipped manually during a set time in the molten paraffin of set temperature (see Table 1 ). For comparison, two cheeses were waxed with Paradip^® natural P 087650 using automated mechanical waxing equipment. After several weeks the cheeses were examined for pillowing / release of the wax layer from the coating layer. The results are given in Table 1.

The cheeses treated with paraffin containing EVA showed no release of the wax, whereas the cheeses treated with paraffin without added EVA showed an increasing amount of release. Adhesion of the cheese wax to the cheese coating was further investigated by cutting loose and tearing off the wax layer from the coating layer. Cheese wax . containing EVA was found to adhere considerably stronger to the cheese coating than cheese wax without added EVA. Example 2 In the following experiment the positive effect of EVA on cheese wax adhesion to the coated cheese surface was demonstrated on various types and sizes of cheese. Cheese wax, Crompton^® KW 13456 acquired from Crompton BN., was molten in a 200 Litre wax machine containing approx. 150 kg cheese wax. In the same wax machine, 4.5 wt% EVA, Escorene^® 02528 containing 28 wt% Vinyl acetate acquired from Exxon Chemical, was mixed with the melted cheese wax to form a homogeneous liquid. Various hard and semi-hard PVA-coated cheeses were dipped for 6 seconds in the molten paraffin of set temperature, prior to and after adding the EVA (see Table 2). For comparison, some cheeses were waxed with Paradip^® natural P 087650 using automated mechanical waxing equipment. After several weeks the cheeses were examined for pillowing / release of the wax layer from the coating layer. The results are given in Table 2, using the following sample coding.

A Crompton at 105°C; dipping time 6 sec.

B Crompton at 115°C; dipping time 6 sec. C Crompton plus 4.5 wt% EVA at 1 15°C; dipping time 6 sec. D Paradip at 98°C; dipping time 6 sec; on automated mechanical equipment.

1 Semi-hard Gouda-type 4.5 kg cheese, 27 days old, 8 cheeses. 2 Semi-hard Amsterdammer-type 4.5 kg fat cheese, 24 days old, 6 cheeses. 3 Semi-hard Maasdammer-type 13 kg eyehole cheese, 34 days old, 16 cheeses. Table 2

For some of the cheeses, the cheese coating plus wax multilayer showed partial release as a whole from the cheese. The extent to which the coating released from the cheese varied for the different cheese types and increased when the cheeses remained longer in the paraffin. Cheeses waxed on automated mechanical equipment barely showed complete coating release. This is probably because of the greater release of paraffin from the coating which allowed release of gas from the cheese. Most problems with paraffin adhesion are known to occur in eyehole cheese because of the greater amount of gas formation in the cheese. The wax release results for this type of cheese (3: Maasdammer-type) clearly show that addition of EVA improves wax adhesion. Crompton^® wax adheres better to the cheese coating than Paradip^® wax, but addition of EVA results in an almost complete reduction of paraffin release. Adhesion of the cheese wax to the cheese coating was further investigated by cutting loose and tearing off the wax layer from the coating layer from some of the cheeses. Crompton wax adhered much better to the cheese than Paradip wax. Increased wax temperature had a positive influence on the wax adhesion. Additionally, cheese wax containing EVA was found to adhere considerably stronger to the cheese coating than cheese wax without added EVA. Example 3 In the following experiment the positive effect of EVA on cheese wax adhesion to the coated cheese surface was demonstrated on Gouda-type cheese. Cheese wax, Paradip natural P 087650 acquired from Paramelt BN., was melted in a 200 Litre wax machine containing approx. 150 kg cheese wax. In the same wax machine, 4.5 wt% EVA, Escorene^® 02528 containing 28 wt% Vinyl acetate acquired from Exxon Chemical, was mixed with the molten cheese wax to form a homogeneous liquid. Semi-hard PVA-coated Gouda-type 12 kg cheeses, aged between 22 and 25 days, were dipped for 6 seconds in the molten paraffin of 100°C, prior to and after adding the EVA (see Table 3). After several weeks the cheeses were examined for pillowing / release of the wax layer from the coating layer.

Table 3

The cheeses treated with paraffin containing EVA barely showed any release of the wax. The cheeses treated with paraffin without added EVA showed an increasing amount of release over time. Adhesion of the cheese wax to the cheese coating was further investigated by cutting loose and tearing off the wax layer from the coating layer. Cheese wax containing EVA was found to adhere considerably stronger to the cheese coating than cheese wax without added EVA.

Claims

C LAI MS

1. A wax comprising 0.05 to 28% (w/w) of poly (ethylene vinylacetate) (EVA), suitable for use in coating cheese.

2. A wax according to claim 1 which comprises less than 10% (w/w) of softeners or plasticisers.

3. A wax according to claim 1 which is free from softeners or plasticisers.

4. A wax according to any one of the preceding claims which is free from a softener based on butadiene.

5. A wax according to any of the preceding claims in which 20% or less of the ethylene, preferably 10% or less an more preferably 5% or less of the ethylene of EVA is replaced by another olefin for example isobutylene or propylene.

6. A cheese coated with the wax as defined in any one of claims 1 to 5.

7. Use of poly (ethylene vinylacetate) (EVA) or a wax comprising EVA to prevent gas bubbles in a cheese coating, under the wax layer and/or to improve adhesion of the wax to cheese or to an inner/first later coating the cheese.

8. Use according to claim 7 wherein the wax is defined in any one of claims 1 to 5.

9. A method of coating cheese or further coating an inner/first layer coating the cheese, the method comprising applying a wax as defined in any one of claims 1 to 5.

10. A method according to claim 9 wherein the inner/first layer coating the cheese is a plastic or polymer coating.

11. A method according to claim 9 or 10 wherein the inner/first layer coating the cheese comprises polyvinyl acetate (PVA).