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Patties and sausage batters were made from trimmed brisket, chuck, striploin, hindshank, silverside, thick flank and rib trim from grass-fed Friesian cows. Functionality of each meat cut was determined from cook yield and true stress and strain of cooked sausage batters and cook yield, dimensional changes and peak force of cooked patties. Colour of raw and cooked slices from the meat cuts and cooked batters was evaluated using a colorimeter and a consumer panel. Composition of raw meat from all cuts was similar; chuck and rib trim had higher pH values and were more red than meat from other cuts. Cooked batters from striploin, chuck and hindshank had higher stress and strain values than gels from other cuts. Patties made from thick flank and striploin were the softest and had the highest cook yield. Batters and patties made from meat with higher salt soluble protein content retained more water and fat on cooking, were more cohesive and had higher bind strengths. Manufacturers can use functionality characteristics to select meat for specific products.

Two separate experiments investigated the effect of breed (Bos indicus, Bos indicus×and Bos taurus), gender/age and chilled and frozen storage on the processing characteristics of roasts made from inside rounds (semimembranosus, adductor and gracilis muscles). Roasts were injected with a salt/phosphate brine and cooked to an internal temperature of 63 °C. Freezing the meat increased purge lost from the raw meat. Country of origin had no significant effect on cook yield. Sensory evaluations with a US consumer panel indicated only slight sensory differences due to country of origin and breed but a significant effect from storage regime. Tenderness comparisons between breeds were confounded by country of origin and indicated that roast beef from inside rounds from Brahman cattle had lower WBS values than roast beef made from inside rounds from British cattle. Although breed and age/gender often significantly affected processing characteristics of the roasts, differences were small and would have little practical or economic importance for selecting the type of meat for this market sector.

The processing characteristics of roasts manufactured from either high or normal pH bull inside rounds (semimembranosus and adductor muscles), which had been stored chilled or frozen, were investigated. Roasts were injected with a salt/phosphate brine and cooked to an internal temperature of 63 °C in a 70 °C water bath. High-pH meat that had been frozen had less purge than normal pH meat. However, pH did not affect purge from chilled meat. Meat pH and storage conditions did not affect retention of pumped brine. Cook yields were significantly (P<0.05) higher for roasts made from high pH meat (103.8 vs 98.8%). Raw and cooked meat colour was affected by meat pH but not storage condition. Cooking reduced the effect of pH on meat colour but cooked roasts manufactured from high pH meat were redder than roasts manufactured from normal pH meat.

Two experiments were done to determine the effect of storage conditions and meat cut on the processing characteristics of beef roasts. The first experiment examined the effect of storage condition (fresh/frozen), cap on/off, thawing regime and holding time post thawing on purge, brine uptake, cook yield and colour of raw and cooked roasts. The second experiment examined the effect of meat cut (insides/flats) and chilled storage for up to 8 weeks on processing characteristics of roast beef. Purge was greater for insides stored frozen without cap and air thawed. Frozen thawed cuts had increased brine retention after injection, after tumbling and after cooking. Flats had less purge and higher cook yields when manufactured into roast beef. Raw and cooked colour was not significantly affected by most factors investigated. Raw meat was more red than meat that had been frozen.

The effect of thawing and cooking regimes on the processing characteristics and colour of cooked roast beef made from frozen beef cap-on inside round (semimembranosus, adductor and gracilus muscle) was investigated. After thawing in air or water, the cap was removed and the insides were pumped (110%), tumbled (30 min continuously) and then cooked in either constant-temperature water baths or baths where a 10 °C difference was maintained between the roast and the water to an internal temperature of 63 or 80 °C. Purge was higher for insides thawed in air. Insides that were cooked at a constant temperature had higher cook yields the same was seen for lower end-point temperatures. Colour of raw insides thawed in water was slightly redder than insides thawed in air. Thawing and cooking regime did not affect the colour of cooked slices but the higher the end temperature, the higher the Hunter L and the lower the Hunter a and b values. Data from this research suggests that roast beef manufacturers should evaluate thawing and cooking procedures to ensure they optimize their process.

The effect of rigor temperature (RT, 35 versus 10°C), increased ionic concentration (MS, 0 versus 0·2% mixed salts), oxidized lipids (OL, 0 versus 1% added oxidized fat), increased free amino acids (FAA, 0 versus 0·3% added mixture of amino acids), fat content (FC, 0 versus 15% added fat) and excluding atmospheric gases (V, 0 versus 99·9% vacuum) on pH and colour of mince stored for one month at -20°C was studied using a complete 2(6) factorial design. Adding FAA increased the meat pH measured after storage (p<0·001). Meat lightness (Hunter L* value) was increased by increased fat content (p<0·001), higher rigor temperature (p<0·001) and oxidized lipids (p<0·05). Vacuum packing tended to preserve redness (Hunter a*) whereas the higher rigor temperature decreased redness (p<0·001). Vacuum packing (p<0·05) and increased fat content (p<0·001) increased yellowness (Hunter b*). The hue angle was lowered by increased salt concentration (p<0·01), increased free amino acids (p<0·01) and using vacuum packing (p<0·001), whereas it was raised (p<0·001) by increased fat content and higher rigor temperature. Various significant two-and three-way interactions are tabulated and discussed.

The effect of rigor temperature (RT, 35 versus 10°C), increased ionic concentration (MS: 0 versus 0·2% mixed salts), oxidized lipids (OL, 0 versus 1% added oxidized fat), increased free amino acids (FAA, 0 versus 0·3% added mixture of amino acids), fat content (FC, 0 versus 15% added fat) and excluding atmospheric gases (V, 0 versus 99·9% vacuum) on protein functionality in mince stored 1 month at -20°C was studied using a complete 2(6) factorial design. All factors studied affected the functional properties of beef. Fresh 24hr samples that entered rigor at 35°C had lower total (TPS), myofibrillar (MPS) and sarcoplasmic (SPS) protein solubilities than samples entering rigor at 10°C (p<0·01). During frozen storage, RT, MS and OL alone did not affect protein solubilities, FAA increased TPS but did not affect MPS and SPS, increasing the meat's fat content raised TPS and SPS but did not affect MPS, applying a vacuum increased TPS and MPS but lowered SPS (p<0·05). Cook yield of frozen stored mince increased with higher FAA but decreased with higher fat content, and the peak force of patties made from frozen stored mince was lowered by increased MS and low FC during storage. Various significant interactions are tabulated and discussed.

Within 45 min post-mortem, 10mm thick strips of semitendinosus muscle from both unstimulated and high voltage stimulated heifer sides were held at 0, 5, 10, 25 and 35 °C for 24 hr, during which they entered rigor. Half the samples were frozen and stored at -20 °C for one month. The pH, sarcomere length, drip, total (TPS), myofibrillar (MPS) and sarcoplasmic (SPS) protein solubilities, and Hunter L (∗), a (∗) and b (∗) values were determined at 24 hr and on thawed samples. Electrical stimulation did not significantly affect any of the parameters measured. The ultimate pH of samples entering rigor at 10 and 25 °C was lower (p < 0.001) than that of samples held at the other temperatures. Rather surprisingly, there was no significant difference in sarcomere length due to rigor temperature. Samples entering rigor at 35 °C had lower TPS, MPS and SPS values than samples held at 0 to 25 °C (p < 0.001). The MPS increased with rigor temperature up to 25 °C (p < 0.001). Drip and total moisture losses, and Hunter L (∗), a (∗) and b (∗) values also increased with rigor temperature (p < 0.001) whereas SPS decreased and NMR meat water spin-lattice relaxation time (T1) shortened with increasing rigor temperature (p < 0.001). Hue angle and cook loss decreased with rigor temperature in 24 hr samples but increased with rigor temperature in frozen samples. After frozen storage, SPS, T1, cook loss and Hunter L (∗), a (∗), b (∗) values decreased, but TPS, MPS, drip losses and hue angle increased. There were significant (p < 0.05) correlations between SPS, hue angle, drip losses and T1.

The colour stability of finely chopped fresh sausages made from post-rigor, pre-rigor salt added (1.5% w/w) or pre-rigor no salt added beef mince was evaluated using a Hunter Miniscan (L (∗) a (∗) b (∗)) and sensory colour panel. Batters were chopped for various times and sausages stored at -1.5 °, + 4.0 ° and + 8.0 °C. Regardless of meat source or chopping time, colour stability was greatest at -1.5 °C. Panellists found the colour of all sausages stored at -1.5 °C acceptable for at least six days. Sausages made from unsalted pre-rigor mince had markedly better colour stability than those made from the other meats, especially when stored at 4 °C or 8 °C.

The functionality and microbial storage life of pre-rigor beef mince stored at -1.5 °C under vacuum or a saturated carbon dioxide atmosphere, or at -18 °C in polyethylene bags, was investigated. Salt (2% w w ) or salt plus the cryoprotectant Polydextrose(®) (2%/2.6% w w ) was added pre-rigor to some samples. Chilled storage decreased salt soluble protein (SSP) by 13-18% (P < 0.01); frozen storage decreased SSP content by 20%. Pre-rigor salted mince in saturated carbon dioxide packs had a satisfactory microbial quality after 12 weeks storage. The cook yield of finely comminuted sausage batters made from that mince and from fresh pre-rigor mince were similar, although batter stress and strain decreased with chilled storage. Adding Polydextrose(®) to salted mince improved batter strain compared with the non-additive and salt-only samples and improved batter stress compared with the salt-only samples. The microbial storage life of chilled vacuumpacked unsalted mince was less than 6 weeks; pre-rigor salting increased its storage life.

Restructured beef roasts, made to a standardized formulation, were prepared using the following types of meat that had been stored at - 18 °C for 5 or 10 weeks: grass-fed bull beef pre-rigor injected with a salt/phosphate brine; uninjected grass-fed bull beef; uninjected grain-fed beef; a 50:50 blend of pre-rigor injected grass-fed bull beef and grain-fed beef; and a 50:50 blend of uninjected grass-fed bull beef and grain-fed beef. After frozen storage, pre-rigor injected beef had a higher (p < 0.05) ultimate pH than uninjected beef . Grain-fed beef had the lowest ultimate pH. Roasts made from pre-rigor injected beef were redder (higher Hunter a(∗) values) than roasts made with uninjected beef (p < 0.05). Roasts made from grain-fed beef were lighter and looked more cooked (higher L(∗) and lower a(∗) values respectively) than those made with grass-fed beef. Extending frozen storage to 10 weeks decreased the cook yield (p < 0.05), peak force (p < 0.001) and extensibility (p < 0.05). Consumer panellists preferred (p < 0.05) roasts made from pre-rigor injected beef for tenderness, juiciness and overall acceptability compared with roasts made from uninjected beef.

Pre-rigor beef mince with 2% added salt was stored under CO(2) at -1.5 °C (A). The same mince with 100 ppm sodium nitrite was stored under CO(2) at 5 °C (B) and -1.5 °C (C), and under vacuum at -1.5 °C (D). Microbiological and sensory analyses were carried out for up to 21 weeks. Indicative storage life was taken as the time for microbial numbers to reach 10(7) colony forming units per g. Mince stored under regimes B or D attained these numbers by 6 and 14 weeks, respectively; mince stored under regimes A and C had not attained these numbers by the end of the storage trial. Mince stored at 5 °C developed storage flavours of sufficient intensity to be detectable by consumers by 9 weeks storage. In general, the other minces did not develop unacceptable levels of storage or off flavours. Over 90% of the added sodium nitrite had disappeared after 10 weeks of storage, partly through conversion to sodium nitrate. Mince pH was not affected by the storage conditions and remained at about 6.0. The water holding capacity of the pre-rigor mince deteriorated during prolonged storage.

The functional properties of thawed pre-rigor beef that had been minced and salted or not salted when its pH value reached 6.8, 6.6, 6.4, 6.2 and 6.0, then immediately frozen, were determined. The mince samples were used to manufacture a finely comminuted sausage batter. Presalting before frozen storage resulted in higher (p < 0.05) thawed mince pH, and batter cook yield and shear strain, and lower (p < 0.05) mince salt soluble proteins, thaw drip and Hunter L(∗) and b(∗) values and batter shear stress than unsalted controls. The pre-rigor pH at time of salting/mincing affected (p < 0.05) thaw drip (unsalted mince only), Hunter L(∗) and b(∗) values and shear stress. Shear stress tended to increase (p < 0.01) and Hunter L(∗) (p < 0.05) and b(∗) (p < 0.01) values tended to decrease with fall in pre-rigor salting pH. No interaction (p > 0.05) between salting and pre-rigor pH at time of salting was observed.

In semimembranosus (SM) muscles removed pre- and post-rigor and injected 10% (wt/wt) with brines formulated to give 2% salt, 1.5% glucose, 0.3% phosphate, 0.15% calcium chloride or 3% sodium lactate in the finished product and cooked within 1 h of injection, cook yields were not significantly affected by processing pre- or post-rigor. Within treatments, however, brine composition had a significant (P < 0.05) effect on cook yields; highest yields were obtained using salt (although this was not significantly different from the water injected control) and lowest yields with calcium chloride. Adding phosphate resulted in lower peak shear force values, and less energy was required to break the sample. The most tender roasts from pre-rigor meat were produced using salt, phosphate or lactate brines and the least tender using calcium chloride. Brine temperature (0-12 °C) during injection had little effect on cook yields or tenderness of the roast beef manufactured pre-rigor. The results indicate that accelerated processing of roast beef can result in finished product with acceptable yields and tenderness if salt and phosphate brines are used.

The effects of variation in the times of mincing post mortem (2, 4, or 6 h), pre-rigor salting (1.5% wt wt ) and freezing rate [fast (10 min, liquid nitrogen); medium (4-6 h at -40 °C and 0.8 m s(-1) air velocity); or slow (36-38 h at -10 °C and 0.1 m s(-1) air velocity followed by 12 h at -20 °C and 0.1 m s(-1) air velocity)] on the functionality of young bull meat were examined using hot-boned forequarters. At 52 h post packaging, the meat was thawed (72 h at 4 °C), its pH measured, and it was used to make finely comminuted batters. Cook yield and stress and strain of the cooked batters were measured. Time of mincing had no effect on meat pH, cook yield or stress and strain. There was a significant interaction (P < 0.05) between pre-rigor salting and freezing rate for pH. Freezing rate did not affect the pH of pre-rigor salted meat whereas the pH of unsalted pre-rigor meat was highest at the fastest freezing rate. Meat salted pre-rigor had a significantly (P < 0.05) higher pH than the post-rigor chilled control. Pre-rigor salting decreased the stress values of cooked batter whereas the slowest freezing rate increased stress. Stress and strain values for cooked batters from thawed meat were not significantly different from the values for batters made from the unfrozen control. Cook yields of batters made from pre-rigor frozen meat were higher than that of the postrigor control but not significantly so. The results indicate that suppliers can use pre-rigor salted and frozen meat when manufacturing comminuted products without major detrimental effects on the cook yield and texture of the finished product.