By Eben van Tonder, 10 August 2026

Where PSE Occurs and What It Means for Product Choice

Pale, Soft and Exudative changes develop mainly in glycolytic, fast twitch muscles, because these muscles have a high glycolytic potential and produce lactic acid rapidly after slaughter. In South African cutting terms this means the Loin (Karree, M. longissimus dorsi) and the Leg cuts, particularly Topside (Oberschale) and Silverside (Unterschale), are among the commercially important sites affected. A rapid pH decline combined with still high carcass temperature denatures myofibrillar proteins before rigor sets in. This reduces water holding capacity, and it is this reduced water holding capacity, not the appearance itself, that governs which products PSE meat is suited to (Rosenvold and Andersen, 2003).

The literature is consistent that whole muscle products sold fresh, whether refrigerated or frozen, are the category most exposed to the visible defects of PSE meat, because paleness and purge in the pack are exactly what the consumer sees before any processing step can correct them (Rosenvold and Andersen, 2003; Pork Information Gateway, Utilization of Pale, Soft, and Exudative Pork). Processed products tolerate PSE meat because salt, phosphate, mechanical protein extraction and, where used, functional binding preparations can restore some of what the raw material itself cannot do.

Table 1. Product Suitability for PSE Meat Inclusion

Product category	Suitability for PSE meat	Reason, with source
Whole muscle fresh or frozen retail cuts	Not suitable	Visible pallor and purge are the primary consumer facing defects, and this is the category most exposed to them because there is no processing step before retail display to correct the appearance (Rosenvold and Andersen, 2003)
Bacon, whole muscle, cured and sliced, vacuum packed, from the belly	Not suitable	This is a separate case from the reformed bacon category below. PSE characteristics in the lean portion of the belly can impair colour, water holding capacity and subsequent bacon quality (Soladoye and colleagues, Review, Pork belly quality, bacon properties and recent consumer trends, cited under cdnsciencepub.com). Excessive purge in the retail pack is undesirable because it affects package appearance and saleable yield
Back bacon, from the loin, cured and sliced	Not suitable	The loin, Karree, is one of the two classic PSE sites, alongside the ham. When loins affected by PSE are processed into back bacon, called Canadian bacon in the United States literature, the product demonstrates poor texture, water holding capacity and colour, the same three defects that affect PSE loin chops (Solomon, Van Laack and Eastridge, 1998, as cited in Pork Information Gateway, Utilization of Pale, Soft, and Exudative Pork). The purge and package appearance and yield problem described above for belly bacon applies equally here, since back bacon is also cured, sliced and vacuum packed
Pressed ham, chunked and formed ham, cooked reformed bacon	Suitable, with binders and mechanical treatment	Salt and phosphate extract myofibrillar protein and restore bind even where starting water holding capacity is low. Blending with red, firm, non exudative meat and adding functional binders is an established practice (Motzer, Carpenter, Reynolds and Lyon, 1998; Schilling, 2002)
Mortadella, polony, Brühwurst, frankfurters and other finely comminuted cooked sausages	Suitable	Fine comminution further dilutes the functional deficit and the emulsion structure depends less on intact muscle fibre architecture than whole muscle products do (Sun, 2009, Utilization of restructuring technology in the production of meat products, a review, CyTA Journal of Food, 7, 153 to 162). South African polony formulation already routinely includes added water, phosphate and a functional extender such as soya protein or mechanically recovered meat to reach target yield, which is the same functional logic that accommodates PSE inclusion (Mapanda, 2011; SANS 885:2022, Edition 4)
Hamburger patties, sold raw and fresh	Generally poor applications for substantial quantities of PSE meat	The product is sold uncooked. Pallor and purge remain visible to the consumer at the point of sale, because there is no cooking step before display. Redden and Chen (1995), as cited in Kuo and Chu (2003), found PSE pork unsuitable for meatball production even with starch included as a binder
Fresh sausages, for example braai sausage or boerewors, in natural casing, sold raw	Generally poor applications for substantial quantities of PSE meat	Same reasoning as patties. Additionally, PSE meat used in dry or semi dry sausage produces a crumbly texture (Pork Information Gateway, Utilization of Pale, Soft, and Exudative Pork)

Bacon: A Separate Case

Bacon has a second problem beyond the visual defect that whole muscle cuts share generally, and this applies whether the bacon is made from the belly or, for back bacon, from the loin. Once the meat is cured and sliced and sits in a vacuum pack at retail, PSE meat is documented to purge substantially more than normal pork (Rosenvold and Andersen, 2003). Excessive purge is undesirable in this context because it affects package appearance, shelf life and saleable yield, showing as liquid pooling around the slices and a loss of the fill weight the pack was meant to hold. For back bacon specifically, this purge and appearance problem sits on top of the texture, water holding and colour defects already documented for PSE loin processed into Canadian bacon (Solomon, Van Laack and Eastridge, 1998, as cited in Pork Information Gateway, Utilization of Pale, Soft, and Exudative Pork), so the loin has the same processing risk into back bacon that it has into fresh chops. This is a separate mechanism from the appearance defect covered above, and it is the reason PSE loins and bellies are treated as a poor raw material for whole muscle, sliced, vacuum packed bacon specifically, distinct from the restructured, reformed bacon category, which is a different product built from PSE tolerant chunks with added binders rather than from an intact, sliced cut.

The Mechanism behind Mechanical Recovery of PSE Meat

When PSE meat is paddle or kidney mixed with good meat for 30 to 40 minutes, in this working process, it behaves differently from normal meat under the same treatment, because its myofibrillar proteins are already partially denatured before mixing begins. The relationship between early postmortem denaturation of porcine muscle protein and loss of water holding capacity is established in the pork quality literature (Rosenvold and Andersen, 2003; Pale Soft Exudative Meat, ScienceDirect Topics overview). Denatured protein does not extract cleanly into the sticky, elastic exudate that normal meat produces under salt and mechanical action. In practical processing, the result can be a distinctly softer, more soft mass under extended mixing. This behaviour is consistent with the impaired protein functionality of PSE meat rather than a processing fault.

Adding a functional binding preparation such as Klebemasse at this stage restores a protein matrix around the PSE particles, serving the same practical purpose of restoring cohesion and bind as transglutaminase treatment in the Milkowski and Sosnicki patent for treating PSE meat (US Patent 5,928,689, 1999), although by a different mechanism from transglutaminase. That patent describes the object of enzymatic or protein based treatment as one that lessens, reverses or repairs the inferior properties of PSE meat, giving reduced cooking purge, improved binding of the muscle pieces and firmer texture, and states that this treatment is particularly well suited to manufactured pork and turkey breast products such as canned or packaged hams. A related patent on massaging PSE meat with supplemental agitation describes the same end point in different words, namely that treated PSE meat can be made to blend in appearance with normal muscle tissue in a finished ham (Method of and apparatus for processing PSE meat, US Patent 6,662,712).

Spices with strong natural colour, added at this stage, mask the residual paleness visually. This does not alter the water holding chemistry, but it addresses the separate, consumer facing appearance defect, and it is consistent with why blending and colour management are treated as two distinct corrective steps in the literature rather than one.

Klebemasse as a Functional Replacement, Not a Chemical Equivalent

Wherever modified food starch, kappa carrageenan, soy protein concentrate or soya flour is used in the studies below to provide additional water retention and structural support, Klebemasse can fulfil that role in this processing system through a meat derived protein matrix, rather than through the hydrocolloid or plant protein mechanisms those ingredients rely on. Because Klebemasse is produced in house from meat rather than purchased as a hydrocolloid or plant protein isolate, this substitution also has an ingredient cost advantage. That cost observation reflects manufacturing economics for this particular system rather than a peer reviewed finding, and does not require validation beyond the actual ingredient costs involved.

In this working process, mechanical breakdown of PSE meat under extended massaging is offset by adding a functional binding system, and the combination is reported to produce a ham that binds well despite the compromised starting material.

Table 2. Ratios, Salt and Phosphate, by Product Category

These figures combine the published PSE inclusion figure from the restructuring literature with a practical working range, and standard salt and phosphate levels documented for cooked, cured, comminuted products. The 15 percent Klebemasse level is the practical working level used here. It is not taken from the published PSE studies. It is markedly higher than the 0.5 to 2 percent inclusion rates documented for modified food starch, soy protein concentrate or kappa carrageenan in the studies below, because those are concentrated hydrocolloid or plant protein isolates added in small amounts, while Klebemasse is a meat derived protein and water carrying preparation added in a larger proportion to do the same structural job.

The PSE meat, Klebemasse and good meat figures are ratios within the structural meat and binder block and therefore total 100 percent within that block. Salt and phosphate are expressed separately as percentages of the final formulation. When a complete recipe is constructed, the structural block must therefore be reduced proportionately to accommodate salt, phosphate, cure, seasoning, water and any other ingredients.

Product	PSE meat	Klebemasse or equivalent binder	Good meat and fatty trim as required by the product	Salt, of total formulation	Phosphate, of total formulation
Pressed ham, cooked reformed bacon	20 to 30 percent, with 25 percent having direct published support	15 percent	55 to 65 percent	1.5 percent	0.4 to 0.5 percent
Mortadella, Brühwurst, frankfurters	20 to 30 percent, as a practical working range	15 percent	55 to 65 percent, including the fat component required for the emulsion	1.5 percent	up to 0.3 percent
Polony	20 to 30 percent, as a practical working range	15 percent, in place of the soya flour or soy protein concentrate that South African polony formulations commonly use at up to 8 percent	55 to 65 percent	1.5 percent	up to 0.3 percent
Hamburger patties, fresh	Generally poor application for substantial quantities	Not applicable, product is not cooked before sale	Balance	Not applicable	Not applicable
Fresh sausage, braai or boerewors type	Generally poor application for substantial quantities	Not applicable, product is not cooked before sale	Balance	Not applicable	Not applicable

Notes on the Sources for These Figures

Schilling (2002), reported in the Pork Information Gateway review, found that combining 25 percent PSE with 75 percent red, firm, non exudative pork, together with soy protein concentrate and modified food starch at 2 and 1.5 percent respectively, gave a chunked and formed ham similar in quality to a 100 percent normal pork sample. Motzer, Carpenter, Reynolds and Lyon (1998) found that a 50 percent PSE, 50 percent normal blend with modified food starch or kappa carrageenan produced better quality restructured ham than 100 percent PSE, and confirmed that modified food starch enhanced water retention of PSE pork specifically. Mapanda (2011), working specifically with South African polony, found soya flour inclusion up to 8 percent and pork rind inclusion up to 16 percent to be common practice for maintaining protein and yield targets in that product. The United States meat science extension literature documents 2.0 to 2.5 percent salt as the conventional level in cooked, cured whole muscle and comminuted products, and states that phosphate above roughly 0.3 percent adds no further value once salt is at that conventional level (Ohio State University Meat Science Extension, Use of Phosphates in Sausage). The same source notes that at lower salt levels, phosphate makes a greater contribution to ionic strength and emulsion stability. The 1.5 percent salt level shown here is lower than that conventional level, chosen to keep the finished product within an acceptable consumer salt perception, and the phosphate level for pressed ham is set towards the upper end of the working range used here, 0.4 to 0.5 percent, subject to the applicable legal maximum for the particular phosphate and product category, to support protein extraction and water binding at this lower salt concentration.

In every one of these studies, the added binder is there to compensate for the same functional shortfall that Klebemasse addresses directly. Soy protein concentrate, soya flour, modified food starch and kappa carrageenan are all purchased inputs added specifically because the meat protein present cannot bind enough water on its own. Klebemasse, being a concentrated meat protein preparation rather than a plant protein or a gum, restores that binding capacity from within the meat system itself, and its use in place of a purchased extender removes that ingredient cost from the formulation while doing the same structural job.

Where no hydrocolloid is used, the entire water binding load falls on salt, phosphate and mechanical protein extraction, together with the functional protein contributed by Klebemasse. This is a different binding system aimed at the same practical water binding and structural target as a formulation using starch or carrageenan. Salt and phosphate together promote extraction and solubilisation of salt soluble myofibrillar proteins, particularly myosin, which provides much of the adhesion, water retention and heat set structure of the finished meat system (Ohio State University Meat Science Extension, Use of Phosphates in Sausage).

Table 3. Practical Water Addition Considerations

The figures below come from three different sources: a United States regulatory brine pump example, a United States federal compositional standard, and a South African polony research trial. None of them were run on a PSE and Klebemasse system specifically, so they are presented here as reference points for practical judgement rather than as proven ceilings for this system. The actual ceiling for any given batch depends on the severity of the PSE condition, the salt and phosphate level used, the strength of mechanical protein extraction, and the Klebemasse inclusion, and should be established by trial.

Product	Practical guidance	Reference point
Pressed ham, cooked reformed bacon	High levels of added water are possible in strongly extracted restructured ham systems, but the practical ceiling must be established for the particular PSE level, salt concentration, phosphate system and Klebemasse inclusion used	A documented brine pump example for a standard cooked, cured ham used a 10 percent by weight injection with 4 percent phosphate and 17.7 percent salt in the brine, giving a finished moisture of 71.2 to 73.7 percent, salt 2.0 percent and phosphate 0.4 percent (Use of antimicrobial polyphosphates in food processing, patent literature, example 6). That example used 2.0 percent salt, higher than the 1.5 percent recommended above, so a Klebemasse based formulation at 1.5 percent salt should rely more heavily on phosphate towards the upper end of the working range used here, subject to the applicable legal maximum for the particular phosphate and product category, and on mechanical protein extraction. Highly enhanced hams generally are reported to reach more than 40 percent added water (Water Works, Meat and Poultry, 2018), though this figure is not specific to a PSE and Klebemasse system
Mortadella and frankfurter type products	Added water must be considered together with fat level and the strength of the extracted protein matrix, since the two interact directly in an emulsion system	United States federal standards cap combined fat and added water at 40 percent of finished product weight, with fat itself capped at 30 percent (9 CFR 319.180). One documented experimental formulation set ran from 10 percent fat with 30 percent added water down to 30 percent fat with 10 percent added water, with added water moving inversely with fat level (Hensley and Hand, 1995, Formulation and chopping temperature effects on beef frankfurters)
Polony	Water level is formulation dependent and must be balanced against mechanically recovered meat, pork rind, Klebemasse and any other protein source used to reach the target meat and extender balance	Mapanda fixed theoretical protein at 10 percent across the treatments by varying mechanically recovered meat, soya flour, pork rind and water. Additional fat was deliberately not added to force the products to 75 percent TME, and the theoretical TME values of the resulting treatments were therefore below 75 percent. The Mapanda formulations also contained 8 percent tapioca starch, together with 1.8 percent salt and 0.3 percent phosphate, so their water levels should not be interpreted as evidence of the amount of water that can be held by a starch free Klebemasse system. A Klebemasse based system should be validated by trial against a comparable total meat equivalent target, since Mapanda’s trial did not include PSE meat or Klebemasse (Mapanda, 2011; South African National Standard SANS 885:2022, Edition 4)

Note on Mortadella Specifically

The United States frankfurter standard is used here as the closest documented benchmark for a finely comminuted, water and fat bearing emulsion sausage governed by salt and phosphate rather than hydrocolloid. Mortadella produced under Italian PGI rules, or under Mercosul or South African standards, may set different permitted fat and moisture ranges, and those standards should be checked directly against the applicable jurisdiction before a final specification is set for that product.

Note on Polony Specifically

SANS 885:2022, Edition 4, is the current South African processed meat standard referenced through VC 9100. The compositional requirements for polony are established under Regulation R.1283 of 2019, as amended. Mechanically recovered meat is defined separately from edible offal and contributes to total meat content unless specifically excluded. The relevant compositional requirements should therefore be checked against R.1283 as amended when a commercial formulation is finalised. Because polony is priced and positioned as a low cost product, the case for replacing soya flour or soy protein concentrate with an in house Klebemasse preparation is stronger here than in mortadella or frankfurters, since the ingredient cost saving is realised on a product where margin is already thin.

Practical Summary

PSE meat is not suited to fresh, uncooked, visually exposed products, because the defect with commercial consequence, pallor and purge, is exactly what the consumer sees before any corrective step can act. It is well suited to cooked, cured, comminuted or restructured products, where salt, phosphate, mechanical protein extraction, and a functional binding preparation such as Klebemasse together compensate for the reduced native protein functionality. Extended paddle or kidney mixing of PSE meat with good meat produces a softer, more broken down mass than the same treatment applied to normal meat, because the starting protein is already partially denatured, consistent with the impaired protein functionality documented for PSE meat generally. Adding Klebemasse at that point restores the missing binding function, serving the same practical purpose as transglutaminase treatment of PSE meat in the patent literature, although by a different mechanism. Colour masking through spice selection addresses the separate, visual dimension of the defect and does not itself change water holding chemistry. Published work provides direct support for approximately 25 percent PSE in chunked and formed cured pork (Schilling, 2002). In practical formulation work, a range of about 20 to 30 percent PSE meat, balanced against good meat and a functional binder, provides a useful starting range, subject to the condition of the meat and the binding system used. Salt at 1.5 percent is recommended here for consumer salt perception, below the 2.0 to 2.5 percent conventional level documented in the meat science extension literature. For this reason, phosphate is kept towards the upper end of the working range, 0.4 to 0.5 percent for pressed ham, subject to the applicable legal maximum for the particular phosphate and product category, and mechanical protein extraction becomes particularly important. This applies equally to pressed ham, mortadella and polony, since all three depend on the same salt, phosphate and mechanical protein extraction principle, and polony formulation in South Africa already includes a purchased extender, usually soya, for the same water binding reason. Wherever such a purchased extender is called for in the literature, an in house Klebemasse preparation can fulfil that role through a meat derived protein matrix, which is a functional replacement rather than a chemical equivalent, while removing that ingredient cost from the formulation.

References

Hensley, J. L. and Hand, L. W. (1995). Formulation and chopping temperature effects on beef frankfurters. Journal of Food Science, 60(1), 55 to 57, with some bibliographies also recording a continuation on page 67.

Kuo, C. C. and Chu, C. Y. (2003). Quality characteristics of Chinese sausages made from PSE pork. Meat Science.

Mapanda, C. (2011). Utilisation of pork rind and soya protein in the production of polony. MSc thesis, Stellenbosch University.

Method of and apparatus for processing PSE meat. United States Patent 6,662,712.

Milkowski, A. L. and Sosnicki, A. A. (1999). Method for treating PSE meat with transglutaminase. United States Patent 5,928,689.

Motzer, E. A., Carpenter, J. A., Reynolds, A. E. and Lyon, C. E. (1998). Quality of restructured hams manufactured with PSE pork as affected by water binders. Journal of Food Science, 63(6), 1007 to 1011.

Ohio State University Meat Science Extension. Use of Phosphates in Sausage. meatsci.osu.edu.

Pork Information Gateway. Utilization of Pale, Soft, and Exudative Pork. porkgateway.org.

Redden, R. R. and Chen, T. C. (1995). Use of PSE pork in Chinese meatball and dried meat floss manufacture, as cited in Kuo and Chu (2003).

Regulation R.1283 of 2019, as amended. Regulations Regarding the Classification, Packing and Marking of Processed Meat Products, South Africa.

Rosenvold, K. and Andersen, H. J. (2003). Factors of significance for pork quality, a review. Meat Science, 64(3), 219 to 237.

Schilling, M. W. (2002). Use of response surface modeling to evaluate the effects of non meat adjuncts and combinations of PSE and RFN pork on water holding capacity in the production of boneless cured pork, as cited in Pork Information Gateway, Utilization of Pale, Soft, and Exudative Pork.

Soladoye and colleagues. Review, Pork belly quality, bacon properties and recent consumer trends. Canadian Journal of Animal Science, cdnsciencepub.com. Full author list and year not confirmed from the material retrieved, cited by lead author name and title.

Solomon, M. B., Van Laack, R. L. J. M. and Eastridge, J. S. (1998). Biophysical basis of pale, soft, exudative PSE pork and poultry muscle, a review. Journal of Muscle Foods, 9, 1 to 11.

South African National Standard SANS 885:2022, Edition 4. Processed meat products. Replaces SANS 885:2011, Edition 3, and is referenced as a compulsory specification through VC 9100, the Compulsory Specification for Processed Meat Products.

Sun, X. D. (2009). Utilization of restructuring technology in the production of meat products, a review. CyTA Journal of Food, 7(2), 153 to 162.

Use of antimicrobial polyphosphates in food processing. Patent literature, example 6, cooked sectioned and formed boneless ham specification.

Water Works. Meat and Poultry, 2018. meatpoultry.com.

9 CFR Section 319.180. Frankfurter, frank, furter, hotdog, wiener, vienna, bologna, garlic bologna, knockwurst, and similar products. Electronic Code of Federal Regulations.