A Referenced Technical Guide for South African and West African Processing Conditions

Eben van Tonder  |  EarthwormExpress  |  11 May 2026  | 

1. Governing Principles of Myosin-Based Binding in the Klebemasse

The Klebemasse is a small fraction of the total meat weight that is prepared exclusively from the highest-binding primals of each species. It is salted and worked to full myosin extraction before being combined with the main meat charge. Its function is to serve as a protein reservoir and binding index carrier for the total batch. [1, 2]

Three scientifically established factors govern binding power in any lean meat fraction used for Klebemasse preparation.

1.1 Myosin Heavy Chain Isoform Density

Skeletal muscles of mammals contain four major myosin heavy chain isoforms: slow beta-MHC (type I), IIa, IIx, and IIb. [3] The fast isoforms IIa, IIx, and IIb are each associated with higher myosin content per unit fibre cross-section than the slow type I isoform. [4] Because binding capacity in meat processing correlates with the quantity of extractable myosin heavy chain per gram of lean, muscles with higher proportions of fast-twitch fibres (type IIa and IIx in the context of beef and pork, and type IIb in chicken) deliver superior binding power per unit weight in the Klebemasse fraction. [5, 6]

1.2 Lean Mass Fraction

Binding power as measured by the Carpenter-Saffle-LaBudde Bind Index correlates directly with lean mass fraction and inversely with fat content. [1, 7] Fat at the cut surface forms a physical barrier between the salt solution and the myofibrillar protein, reducing extraction yield. Therefore the Klebemasse fraction must be trimmed to below 1 percent visible fat and connective tissue before salt is applied.

1.3 pH at Processing and the Isoelectric Point of Myosin

The isoelectric point of myosin in the meat protein system is approximately pH 5.0 under no-salt conditions, shifting to approximately pH 4.0 with 2 percent NaCl addition. [8] Water-holding and gel-forming capacity reach a maximum in the range pH 6.0 to 6.3 in the presence of salt. [8] Myosin solubility therefore increases as pH rises above the isoelectric point, because electrostatic repulsion between protein molecules increases and keeps the protein in the aqueous phase. [9] A 0.6 M KCl solution at pH 6.0 produces greater myosin filament dissociation and solubilisation than the same solution at lower pH. [10]

This principle has a direct consequence for DFD and PSE raw materials, which is addressed in Section 3 below.

2. Top Five Muscles by Species for Klebemasse Preparation

The following rankings integrate the Carpenter-Saffle-LaBudde Bind Index data [1], the published BAFF Fleischtechnologie classification system, and peer-reviewed data on myosin heavy chain isoform density and salt-soluble protein extractability by muscle type. [5, 6, 11, 12] For Klebemasse formulation, only ranks 1 to 3 should be used as the primary extraction fraction. Rank 4 and rank 5 are included as supporting options when prime cuts are not available or when cost requires substitution.

2.1 Beef

Research on seven muscles of cattle (semitendinosus, longissimus thoracis, rhomboideus, gastrocnemius, infraspinatus, psoas major, and biceps femoris) has established that muscles with higher type IIB and type IIA fibre proportions show greater total protein solubility across post-mortem aging periods. [11] The semimembranosus and biceps femoris, as the primary muscles of the topside and silverside respectively, consistently score highest in binding functionality across multiple published Bind Index compilations. [1, 7]

Rank	Primal (German)	Primary Muscle Group	Predominant Fibre Type
1	Topside / Oberschale	Semimembranosus	Type IIA / IIX predominant
2	Silverside / Unterschale	Biceps femoris	Type IIA / IIX
3	Chuck roll / Bug, Schulterdeckel	Triceps brachii, infraspinatus	Mixed IIA / IIX
4	Shank lean / Hesse, Wadschinken	Gastrocnemius, deep digital flexors	Mixed I / IIA
5	Heel of round / Nuss-Anteil	Rectus femoris, vastus medialis	Type IIA / IIX

2.2 Pork

For pork, the BAFF S2 classification describes sinew-free pork shoulder as the prime Brat and Klebemasse component in German processing technology. Published Bind Index data compiled by Carpenter, Saffle, Ockerman, Anderson, and Bell, and reviewed by LaBudde and Lanier (1995), confirm that pork shoulder (blade and chuck area, Triceps brachii) carries the highest bind value per unit protein among commercial pork primals. [1, 7] The inside ham (Semimembranosus and Rectus femoris) follows closely. The longissimus dorsi, despite being the premium steak cut, has a lower proportion of fast-twitch fibres in commercial pigs and therefore a lower binding value per gram than the shoulder.

Rank	Primal (German)	Primary Muscle Group	Predominant Fibre Type
1	Inside ham / Oberschale, Nuss	Semimembranosus, rectus femoris	Type IIA / IIX
2	Shoulder S2 sinew-free / Schulter	Triceps brachii, lower shoulder	Type IIA predominant
3	Loin eye trimmed / Kotelettrucken	Longissimus dorsi	Type IIA / IIX mixed
4	Outside ham / Unterschale	Biceps femoris	Type IIA / IIX
5	Neck lean trimmed / Halsfleisch S3	Cervical and splenius groups	Mixed I / IIA

2.3 Chicken

Chicken pectoralis major is composed of 100 percent type IIb fast-twitch fibres in commercial broilers. [13, 14] This is unique among the species considered here. Research on the denaturation of chicken myofibrils demonstrated that chicken pectoralis (white) fibres are least susceptible to denaturation at pH 5.4 and 40 degrees Celsius compared to red myofibrils from the same bird, indicating that white muscle proteins are more stable under processing conditions that cause PSE-type damage. [15] The published literature therefore supports chicken breast as a strong Klebemasse candidate on the basis of its fibre type profile and denaturation resistance, although a direct cross-species comparison of myofibrillar protein solubility at a standardised ionic strength across all commercial primals has not been established in a single peer-reviewed study. This ranking should therefore be treated as a well-supported processing inference, pending local cook loss and texture trials in each production environment. Temperature during Klebemasse preparation must not exceed 10 degrees Celsius for chicken.

Rank	Primal (German)	Primary Muscle Group	Predominant Fibre Type
1	Breast / Huhnerbrustfleisch	Pectoralis major	100% type IIb fast-twitch glycolytic
2	Thigh skin-off / Oberschenkel	Biceps femoris, semimembranosus	Type IIA / IIX
3	Drumstick skin-off / Unterschenkel	Gastrocnemius, digital flexors	Mixed IIA / IIX
4	Breast tender / Supracoracoideus	Pectoralis minor	Type IIb
5	Wing meat skin-off / Flugelfleisch	Pectorals, biceps brachii	Type IIb / IIA

2.4 Lamb and Sheep (including West African Savannah breeds)

In sheep and goats, published work on lamb muscle fibre composition confirms variation in fast-twitch fibre proportions between muscles, depending on breed, body weight at slaughter, and management system. [16, 17] The biceps femoris and triceps brachii muscles showed significant proportions of fast-twitch fibres across several breed comparisons, and the semitendinosus showed higher fast-twitch proportions than the longissimus lumborum in direct comparisons. [16] The shank musculature in small ruminants is associated with sustained locomotor demand, which selects for higher fibre activation frequencies and therefore higher fast-twitch fibre recruitment. The shank (Haxe) is therefore placed at rank 1 as a supported processing inference based on the available fibre-type data and on the Bind Index principle that muscles subject to sustained high-frequency activation carry higher myosin density. However, a directly measured cross-muscle Bind Index ranking table for sheep and goat equivalent to the Carpenter-Saffle data for beef and pork has not been published. The following ranking should be validated by local cook loss and texture trials before being adopted as a standing plant parameter.

Rank	Primal (German)	Primary Muscle Group	Predominant Fibre Type
1	Shank / Haxe	Gastrocnemius, superficial and deep digital flexors	Mixed IIA / IIX high proportion
2	Shoulder lean / Schulter	Triceps brachii, subscapularis	Type IIA predominant
3	Leg inside trimmed / Keule Oberschale	Semimembranosus, biceps femoris	Type IIA / IIX
4	Neck lean trimmed / Nacken, Hals	Cervical and splenius groups	Mixed I / IIA
5	Chuck forequarter lean / Bug	Chuck roll group, clod	Mixed IIA / IIX

3. DFD in Beef and PSE in Pork: Scientific Basis for Routing Decisions

3.1 Dark Firm and Dry (DFD) Beef
Parameter	South African Context	West African Zebu Context
Definition	Ultimate pH above 6.2 due to pre-slaughter glycogen depletion. Cattle breeds known for nervous temperament, including Bos indicus, are associated with higher DFD incidence. [18]	West African Zebu (White Fulani, Red Bororo, Shuwa, Sokoto Gudali) are managed under extensive systems. A case study of 30,230 Nellore carcasses found that long transport distances did NOT significantly affect ultimate pH (P = 0.63), and concluded that the Nellore breed’s heat tolerance and low transport stress were likely protective factors. [19] The primary drivers of elevated ultimate pH in Zebu material appear to be animal maturity, carcass weight, and handling stress at the point of lairage and stunning, rather than transport distance per se. The structural DFD risk in West African Zebu operations therefore relates to lairage and pre-slaughter handling quality, not transport distance alone.
Effect on myosin solubility	Elevated pH in DFD meat moves the muscle pH further above the isoelectric point of myosin (pH 5.0 under no-salt conditions). This increases net negative charge on the protein and therefore electrostatic repulsion between myosin molecules, keeping myosin in solution more readily at a given salt concentration. [8, 9] Myosin gel strength is maximised at pH 6.0 to 6.3 in the presence of salt. [8]	This advantage applies fully to West African Zebu DFD material. Because Zebu pH at processing routinely reaches 6.3 to 6.5, the myosin extractability advantage is often greater than in South African feedlot cattle. Bos indicus muscle has inherently more oxidative metabolism than Bos taurus muscle. [20] This oxidative character contributes to higher pH post-mortem under stress conditions.
Routing in Klebemasse	DFD trim from topside and silverside is NOT routed into the Klebemasse fraction itself because its dark colour requires management and because the Klebemasse salt and temperature parameters are set for the highest-grade lean. DFD trim contributes positively to the main meat charge and is acceptable in the bulk fraction up to 40 percent of total.	Identical routing logic applies. DFD Zebu trim from round and chuck is routed to the bulk fraction. Because its elevated pH already increases its own myosin extractability, a Klebemasse fraction of 15 to 20 percent is sufficient to carry the whole batch including 40 percent DFD trim in the remainder.
Colour management	DFD beef colour (dark purple to near-black) must be compensated by nitrite level, paprika, and carmine where permitted, in light-coloured product lines.	Identical approach required. Nigerian and West African regulatory standards for nitrite use follow Codex Alimentarius limits. Paprika and rooibos-fraction antioxidants assist colour stability in the finished product.

3.2 Pale Soft Exudative (PSE) Pork
Parameter	South African Context	West African Zebu Context
Definition	Rapid post-mortem glycolysis at high muscle temperature (above 38 degrees Celsius) causes pH to fall to below 6.0 within 45 minutes while temperature is still high. This causes irreversible denaturation of myosin before the rigor bond can form and protect it. [21, 22]	PSE pork is less common in West African pork production because indigenous pig breeds are generally slower-growing than the commercial Dutch and Danish lines dominant in South African abattoirs. However PSE risk increases as imported genetics spread through urban production systems.
Effect on myosin	PSE myosin is permanently compromised before processing begins. Myosin in PSE pork has smaller head size, lower ATPase activity, decreased enthalpy of denaturation, and lower solubility compared to normal pork myosin. [23] Myosin filament length is reduced by approximately 8 to 10 percent. [22] PSE myosin cannot form a functional gel network regardless of salt level, ionic strength, or tumbling time.	Same irreversible denaturation mechanism applies. No salt level, phosphate addition, or processing intervention can restore PSE myosin function. [23, 24]
Routing in Klebemasse	PSE trim is ABSOLUTELY EXCLUDED from the Klebemasse fraction. There are no exceptions. For emulsified sausage lines, published work shows that processing PSE pork at high ionic strength in the presence of added polyphosphate can narrow the difference in cook loss between PSE and normal pork, although texture (shear stress and true shear strain) remains inferior to normal pork under the same conditions, and no combination of conditions tested made all functional properties of PSE pork equal to those of normal pork. [23] PSE trim is therefore routed to emulsified product lines only, where salt and phosphate levels can be adjusted to partially compensate, at a maximum inclusion rate of 30 percent of the lean fraction.	Identical ruling applies. Any PSE trim identified at intake is routed to emulsified sausage or pate lines. It must never contact the Klebemasse fraction. The high ionic strength and polyphosphate mitigation described by Xiong and Blanchard (2000) requires precise formulation control, which must be validated in each production facility.
Screening method	pH measurement at 45 minutes post-mortem is the standard screening criterion. A pH45 below 6.08 indicates risk. Visual screening for pale colour and surface exudate at intake is the practical production control. [21]	Same pH45 screening methodology applies. In operations without electronic pH meters, visual and tactile screening (pale colour, wet surface, soft texture) remains valid and is described in the standard EarthwormExpress production SOP.

4. Klebemasse as a Binding Index Fraction: Proportions by Species

The proportion of the total meat weight that must be devoted to the Klebemasse fraction depends on the binding deficit of the remaining meat charge. The following tables present the proportions with a direct comparison between South African processing conditions (commercial feedlot cattle, commercial pork genetics, commercial broiler chicken, feedlot lamb) and West African Zebu processing conditions (extensive cattle, traditional pigs, local chicken breeds, Savannah sheep and goat).

4.1 Beef Sausage
Parameter	South African Context	West African Zebu Context
Klebemasse fraction (ranks 1 to 3 only, pre-extracted)	15 to 20 percent of total meat weight. SA feedlot beef is typically normal pH 5.4 to 5.8. DFD incidence in feedlot systems is lower than in extensive systems.	15 to 20 percent of total meat weight. West African Zebu Klebemasse is prepared from round and chuck of the same carcass as the bulk trim, screened for dark colour and selected for the leanest available.
DFD bulk fraction inclusion	DFD trim acceptable in remainder up to 40 percent of total meat weight. SA feedlot DFD incidence is typically 5 to 15 percent depending on species and handling protocols. [18] This 40 percent figure is an operational processing rule derived from accumulated plant experience and formulation principles, not a universally peer-reviewed threshold. It should be validated by local cook loss, texture, and slicing trials before adoption as a standing plant parameter.	DFD Zebu trim is acceptable in remainder up to 40 percent of total as an operational working rule, subject to the same local validation caveat. Because DFD incidence in Zebu operations is associated with lairage and handling quality rather than transport distance alone [19], the actual proportion of DFD material in any given batch will vary. The practical recommendation is to measure the pH of incoming trim at intake and route accordingly.
Normal pH trim	Balance to 100 percent.	Balance to 100 percent. In Zebu operations the normal-pH fraction will often be smaller than in SA feedlot operations, and the DFD fraction will be proportionally larger.
Salt in Klebemasse	2.0 to 2.5 percent of Klebemasse lean weight, applied before combination with bulk fraction.	2.0 to 2.5 percent of Klebemasse lean weight. Same parameter. Elevated Zebu pH increases extractability at this salt level, making it the more efficient extraction system.

4.2 Pork Sausage
Parameter	South African Context	West African Zebu Context
Klebemasse fraction (ranks 1 to 3, PSE-screened)	20 to 25 percent of total meat weight. The higher proportion compared to beef reflects the requirement to compensate for the zero binding contribution of any PSE trim in the bulk fraction.	20 to 25 percent of total meat weight. Same principle applies. If PSE pork enters the operation, the Klebemasse proportion must be maintained at the upper limit of this range.
PSE trim in bulk fraction	Maximum 30 percent of lean fraction in the bulk fraction for emulsified products. Published work by Xiong and Blanchard (2000) established that high ionic strength combined with polyphosphate addition can narrow the cook loss difference between PSE and normal pork, but texture (shear stress and true shear strain) remained inferior under all tested conditions and no combination of processing conditions made all functional properties of PSE pork equal to those of normal pork. [23] The 30 percent guideline is an operational working rule, not a universally peer-reviewed threshold for all product types. It should be validated by local cook loss and texture trials.	Maximum 30 percent of lean fraction in bulk for emulsified lines, with the same operational caveat. Same polyphosphate mitigation option applies but requires precise formulation control in each facility.
PSE exclusion from Klebemasse	Absolute. No PSE trim may enter the Klebemasse fraction under any circumstances.	Absolute. Same requirement.
Temperature control	Klebemasse temperature must not exceed 4 degrees Celsius during extraction and working.	Ambient temperatures in West African processing environments are higher than in SA. Klebemasse preparation must be conducted with ice and under refrigeration. Failure to maintain temperature below 4 degrees Celsius during pork Klebemasse preparation will cause partial myosin denaturation and loss of binding function. This is a critical control point.

4.3 Chicken Sausage
Parameter	South African Context	West African Zebu Context
Klebemasse fraction (breast and thigh, PSE-screened)	15 to 20 percent of total meat weight. SA commercial broiler operations carry a significant PSE risk because of rapid growth rates and the shift of pectoralis major fibres toward the glycolytic phenotype. [13, 25]	Local West African chicken breeds (breeds such as the Kuchi Kuchi and indigenous forest fowl) have more mixed fibre-type profiles than commercial broilers and lower PSE incidence. However as commercial genetics penetrate urban markets, PSE risk increases.
MDM inclusion	Maximum 15 percent of total. Mechanically deboned meat is excluded from the Klebemasse fraction. Its binding contribution is negligible because the deboning process destroys myofibrillar architecture.	Same MDM limit applies.
Temperature control	Bowl chopper discharge temperature must not exceed 10 degrees Celsius. Chicken myosin denatures at lower temperatures than beef myosin because of structural differences in the chicken fast myosin isoform. [15]	Critical control point in warm climates. Ice addition must be calculated to maintain the 10 degrees Celsius limit throughout the Klebemasse working cycle.
PSE chicken screening	Pale colour, wet surface, and soft texture at the pectoralis major cut face are the screening criteria. pH45 measurement below 6.0 in the breast confirms PSE risk. [15]	Same screening criteria. In the absence of pH meters, visual and tactile screening at intake is mandatory.

4.4 Lamb and Sheep Sausage
Parameter	South African Context	West African Zebu Context
Klebemasse fraction (ranks 1 to 3, trimmed to below 1 percent fat)	15 to 20 percent of total meat weight. SA feedlot lamb (Dorper and Merino crosses) does not present the same DFD or PSE challenges as beef and pork because post-mortem pH decline in small ruminants is less extreme. [16]	West African Savannah breeds (Sudanese Desert sheep, West African Dwarf, Red Sokoto goat) are highly active animals with very low intramuscular fat. Their shank and shoulder present binding power equivalent to or greater than Zebu round and chuck, because of extreme locomotion demands. [16]
Fat taint management	The primary quality constraint in lamb and sheep Klebemasse is ram taint (androstenone and skatole). Taint compounds are lipid-associated. The Klebemasse fraction, trimmed below 1 percent visible fat, is not materially affected by taint compounds. Fat used in the product formulation must be sourced from castrated males or females.	West African ram taint is a well-recognised processing challenge. The Klebemasse fraction is not affected because it is prepared from lean only. Fat addition for flavour balance in the bulk formulation must be screened for taint before use.
Normal pH bulk fraction	No DFD or PSE constraint in the bulk fraction. Balance to 100 percent of total meat weight with trim from neck, flank, and lower-grade shoulder.	Same. West African Savannah sheep and goat trim from neck and flank forms the bulk fraction. Fat is added separately at 15 to 20 percent of total formulation for flavour balance.
Salt in Klebemasse	2.0 to 2.5 percent of Klebemasse lean weight.	Same parameter.

5. Summary Reference Table: Klebemasse Proportions

Species	Klebemasse %	SA Context	West Africa Zebu Context	Critical Exclusion
Beef	15 to 20%	DFD bulk fraction up to 40% of total. Normal pH balance to 100%.	Structurally elevated DFD incidence due to Zebu temperament and transport distances. Same 40% tolerance applies with elevated frequency.	DFD trim excluded from Klebemasse itself. Enters bulk fraction only.
Pork	20 to 25%	PSE trim maximum 30% of lean in bulk. Higher proportion required because PSE contributes zero binding.	Same PSE limit. Warm ambient temperatures require rigorous temperature control during Klebemasse preparation.	PSE absolutely excluded from Klebemasse. No exceptions.
Chicken	15 to 20%	PSE risk in commercial broiler pectoralis is significant. Discharge temperature ceiling of 10 degrees Celsius is mandatory.	Lower PSE incidence in indigenous breeds. Risk increases as commercial genetics penetrate urban markets.	MDM excluded from Klebemasse. PSE breast excluded from Klebemasse.
Lamb / Sheep	15 to 20%	No DFD or PSE constraint. Taint management is primary quality variable.	Savannah breeds carry high binding power due to extreme locomotion. Taint management identical.	Fat from intact rams excluded from Klebemasse and formulation fat charge.

6. Critical Working Parameters for All Species

The following parameters are non-negotiable. They are grounded in the physics of myosin extraction and the irreversibility of myosin denaturation at elevated temperature.

Parameter	Beef and Pork Klebemasse	Chicken Klebemasse
Salt	2.0 to 2.5% of Klebemasse lean weight	2.0 to 2.5% of Klebemasse lean weight
Added water	5 to 10% of Klebemasse lean weight, ice-cold	5 to 10% of Klebemasse lean weight, ice-cold
Maximum temperature	4 degrees Celsius throughout extraction and working	10 degrees Celsius throughout. Critical. Chicken myosin denatures at lower temperature. [15]
Fat content in lean	Below 1% visible fat and connective tissue before salt application	Below 1% visible fat. Skin must be completely removed.
Endpoint	Sticky exudate-rich surface that adheres strongly to adjacent surfaces and stretches slightly under tension without tearing	Same endpoint. Discharge when tacky film forms. Do not over-work.
Preparation sequence	Klebemasse is prepared BEFORE all other processing. It is combined with the salted bulk fraction only after the extraction endpoint is confirmed.	Same sequence. Chicken Klebemasse preparation must happen in the coldest part of the working shift.

References

[1]  Carpenter, J.A. and Saffle, R.L. (1964). A simple method of estimating the emulsifying capacity of various sausage meats. Journal of Food Science, 29, 774-781. Reviewed and corrected values published in: LaBudde, R.A. and Lanier, T.C. (1995). Protein Functionality and Development of Bind Values. Proceedings of the 48th Annual Reciprocal Meat Conference. American Meat Science Association, Savoy, IL, pp. 59-71.

[2]  van Tonder, E. (2020-2026). Protein Functionality, the Bind Index and the Early History of Meat Extenders in America. EarthwormExpress. Available at: https://earthwormexpress.com [Multiple articles in the Klebemasse and Brat series].

[3]  Schiaffino, S. and Reggiani, C. (1994). Myosin isoforms in mammalian skeletal muscle. Journal of Applied Physiology, 77(2), 493-501. PMID: 8002492.

[4]  Reggiani, C. and Bottinelli, R. (1999). Myosin heavy chain isoforms and dynamic contractile properties: skeletal versus smooth muscle. Micron, 30(3), 197-216.

[5]  Faustman, C. and Cassens, R.G. (1994). Myofibrillar protein from different muscle fiber types: implications of biochemical and functional properties in meat processing. Journal of Animal Science, 72(8), 2123-2128. PMID: 8068202.

[6]  Wang, H., Claus, J.R. and Marriott, N.G. (1994). Selected skeletal muscle fibre type as a basis for lean meat primal selection and binding quality assessment. Published data compiled and reviewed by Labudde, R.A. and Lanier, T.C. (1995) in Reciprocal Meat Conference Proceedings, op. cit.

[7]  Acton, J.C. and Saffle, R.L. (1969). Stability of oil-in-water emulsions. Journal of Food Science, 34, 281-284. Bind constant values for commercial meat primals compiled by Carpenter, Saffle, Ockerman, Anderson, and Bell. Corrected table published by LaBudde (1995) op. cit.

[8]  Puolanne, E. and Halonen, M. (2010). Theoretical aspects of water-holding in meat. Meat Science, 86(1), 151-165. doi: 10.1016/j.meatsci.2010.04.038. Citing Hamm (1962) on isoelectric point shift with NaCl addition, and Ishioroshi, Samejima, and Yasui (1979) on myosin gel strength at pH 6.0.

[9]  Zhou, X., Yin, T., Xu, Y., Han, Y. and Nie, S. (2024). The effect of pH and heating on the aggregation behavior and gel properties of beef myosin. Food Chemistry, 435, Article 137542. doi: 10.1016/j.foodchem.2023.137542.

[10]  Malva, A., Russo, F., Mugnai, S., Cassar-Malek, I. and Albenzio, M. (2018). Methods for Extraction of Muscle Proteins from Meat and Fish Using Denaturing and Nondenaturing Solutions. Journal of Food Quality, Article 8478471. doi: 10.1155/2018/8478471. Citing Chen et al. on greater myosin solubilisation at pH 6.0 with 0.6 M KCl.

[11]  Zhang, M., Liang, Y., Bhosale, S., Zhang, W. and Hou, C. (2020). Changes in Physical Meat Traits, Protein Solubility, and the Microstructure of Different Beef Muscles during Post-Mortem Aging. Foods, 9(7), 932. PMCID: PMC7353465. Data on semitendinosus, longissimus thoracis, rhomboideus, gastrocnemius, infraspinatus, psoas major, and biceps femoris.

[12]  LaBudde, R.A. and Lanier, T.C. (1995). Protein Functionality and Development of Bind Values. Proceedings of the 48th Annual Reciprocal Meat Conference, American Meat Science Association, pp. 59-71. Table 1 in this paper presents proximate analysis and functional indices of commercial meat materials compiled from the work of Carpenter, Saffle, Ockerman, Anderson, and Bell. These values constitute the primary published Bind Index data for commercial beef and pork primals. Note: Reference 12 in earlier versions of this document cited Pearce, Hopkins, and Toohey (2011) for this purpose. That citation was not directly traceable to a Bind Index ranking table for the named primals and has been replaced by the LaBudde and Lanier (1995) source, which is the correct primary reference for this data. See also reference 1.

[13]  Kim, H.J., Choi, Y.M., Kim, B.C., Lee, S.H. and Cho, S.H. (2022). Proteolysis and changes in meat quality of chicken pectoralis major and iliotibialis muscles in relation to muscle fiber type distribution. Poultry Science, 101(11), 102134. PMCID: PMC9552107.

[14]  Fang, Q., Gao, Y., Zhao, L. and Tong, H. (2021). The unique physiological features of the broiler pectoralis major muscle as suggested by three-dimensional ultrastructural study of mitochondria in type IIb muscle fibers. Scientific Reports, 11, 23202. PMCID: PMC8636870. Confirming 100 percent type IIb fibre composition of broiler pectoralis major.

[15]  Molette, C., Remignon, H. and Babile, R. (2000). Denaturation of myofibrillar proteins from chickens as affected by pH, temperature, and adenosine triphosphate concentration. Poultry Science, 79(4), 540-545. PMID: 10685897.

[16]  Kozlowski, K., Wojtysiak, D. and Poltowicz, K. (2024). The effect of breed and body weight at slaughter on histochemical muscle fiber characteristics and meat quality of longissimus lumborum and semitendinosus lamb muscles. Livestock Science, Article 105498. PMCID: PMC11653817.

[17]  Wang, Y., Li, Z., Zhang, H., Pan, Y. and Yang, N. (2025). Effects of Muscle Fiber Composition on Meat Quality, Flavor Characteristics, and Nutritional Traits in Lamb. Foods, 14(13), 2309. PMCID: PMC12248750.

[18]  Perez Linares, C., Bolanos Lopez, D., Figueroa Saavedra, F. and Barreras Serrano, A. (2018). An evaluation of environmental, intrinsic and pre- and post-slaughter risk factors associated to dark-cutting beef in a Federal Inspected Type slaughter plant. Meat Science, 145, 98-103. doi: 10.1016/j.meatsci.2018.06.014. Documenting DFD incidence at 13.45% and association with Bos indicus racial origin through excitable temperament (citing O’Neill, Webb, Frylinck, and Strydom, 2006; Voisinet et al., 1997).

[19]  Rodrigues Mendes, N.S., Silva, R.R., Ferreira de Oliveira, T., Ellies-Oury, M.P., Hocquette, J.F. and Chriki, S. (2024). Does transport stress have any effect on carcass quality of Nellore cattle (Bos taurus indicus) in Brazil? A case study. Translational Animal Science, 7(1), txad134. doi: 10.1093/tas/txad134. IMPORTANT CONCLUSION: A linear regression model (R2 = 0.016) failed to show distance having a significant effect on ultimate pH (P = 0.63). The study concluded that long distances did NOT significantly affect ultimate pH in Nellore cattle, attributing this to low stress during transport and the physical heat-tolerance characteristics of the Nellore breed. Carcass weight and maturity were the significant predictors of ultimate pH, not transport distance.

[20]  Ramos, P.M., Antonelo, D.S., Beline, M., Pavan, B., Goulart, R.S., Kirkpatrick, L.T., Gerrard, D.E. and Silva, S.L. (2025). Growth rate and finishing system alter beef color and early postmortem metabolism in Bos indicus crossbred cattle. Meat Science, 230, 109930. doi: 10.1016/j.meatsci.2025.109930.

[21]  American Meat Science Association (2000). Berg, E.P. Instrumentation to Measure Pork Quality. Proceedings of the Reciprocal Meat Conference. Citing van der Wal et al. (1995) on pH45 of 6.08 for slight PSE and pH45 5.84 for severe PSE.

[22]  Warner, R.D. (2014). Influence of high pre-rigor temperature and fast pH fall on muscle proteins and meat quality: a review. Animal Production Science, 54(4), 400-421. doi: 10.1071/AN13329. Citing Izumi et al. (1977) on irreversible actin-myosin binding in PSE conditions.

[23]  Xiong, Y.L. and Blanchard, S.P. (2000). The effect of ionic strength, polyphosphates type, pH, cooking temperature and preblending on the functional properties of normal and pale, soft, exudative (PSE) pork. Meat Science, 55(3), 299-307. doi: 10.1016/S0309-1740(99)00048-0. Key finding: The combination of conditions most effective in reducing the difference between normal and PSE pork was high ionic strength in the presence of added polyphosphate. Under these conditions there was no significant difference in cook loss between normal and PSE pork, although texture (shear stress and true shear strain) of the PSE samples was still inferior. No combination of conditions made all functional properties of PSE pork equal to those of normal pork.

[24]  Kauffman, R.G., Cassens, R.G., Scherer, A. and Meeker, D.L. (1992). Variations in pork quality. National Pork Producers Council, Des Moines, Iowa. Industry reference for PSE routing and product-line management. The 30 percent PSE inclusion guideline in the bulk fraction for emulsified products is an operational rule derived from accumulated processing experience and the Xiong and Blanchard (2000) functional data, not a universal peer-reviewed threshold for all product types. Local validation is required.

[25]  Ma, X., Niu, Q., Wang, Y., Zhang, W., Zhao, S. and Song, X. (2024). Research Progress on Regulating Factors of Muscle Fiber Heterogeneity in Livestock: A Review. Genes, 15(8), 1071. PMCID: PMC11311112. Confirming type IIB fibre predominance in pectoralis major of commercial broilers and glycolytic fibre shift with selection for growth rate. Note: Schiaffino, Gorza and Reggiani (1994) is a separate publication on developmental regulation of MHC isoforms in skeletal muscle, not the same paper as the Genes 2024 review. These two sources address distinct aspects of the same subject and must not be conflated.

[26]  Shackelford, S.D., Wheeler, T.L. and Koohmaraie, M. (2000). Variation in meat quality of South African Sanga and Brahman breeds. Reviewed in: Webb, E.C., Van Niekerk, W.A. and Bosman, M.J.C. (2000). Variation in meat quality characteristics between Sanga (Bos taurus africanus) and Sanga-derived cattle breeds and between Sanga and Brahman (Bos indicus). Animal, 4(11), 1954-1961. doi: 10.1017/S1751731110001941.

[27]  Connolly, J. and Sikes, A. (2023). The extraction of soluble proteins aids salt swelling of pork meat. Food Materials Research, 3, 11. doi: 10.48130/FMR-2023-0011. On salt swelling mechanism and role of myofibrillar and sarcoplasmic proteins.

[28]  Liu, G., Xiong, Y.L. and Butterfield, D.A. (2000). Chemical, physical and gel forming properties of oxidised myofibrils and whey and soy protein isolate gels. Journal of Food Science, 65, 811-818.