Table 1. Reasons and solutions of meat losses in different stages

Stage Reasons Solutions References
Transportation Livestock Fear, fatigue, stress, dehydration, and hunger during transportation and prolonged truckling leads to PSE (pale, soft and exudative) and DFD (dark, firm and dry) meats and quality loss. Proper handling and loading of livestock.Optimal environmental and vehicle conditions.Avoiding prolonged travel times. (Broom, 2008; Cockram, 2014; Knowles and Warriss, 2007; Knowles et al., 2014; Weeks, 2014)
Poultry Long distances with unsuitable vehicles in poor conditions, heat prostration, overcrowding and dehydration. Huge fans should rotate to reduce the temperature.Transportation cars should be parked in shadow and sheltered place and animals should be refreshed with water.
Unloading Poultry Bruising and broken bones.Vehicular crowding.Slaughter and processing areas are overcrowded and noisy.Stressful operations, unloaded chickens, glycogen reduction and higher pH prior to slaughter.Chicken with injury, leg/hip breaks or crippled thrown chickens. Minimize conveyor distance to avoid chicken fall.Avoid roughly manual uploading.Designing waiting salons for animals.Uniformity of birds or adjusted machines between birds.Chicken should not be hung by only one leg.Suspending conditions should be improved to reduce the pain of being stretched by feet. (Chao et al., 2014; Harford, 2014; Smith, 2014; Weeks, 2014)
Poultry Improper electrical immobilization results in blood splash, incomplete bleeding and torturing chickens. Splashing conditions including voltage and water temperature should be monitored for a better feather removal and avoiding consequences of improper stunning.
Sticking Livestock Sticking severs blood loss: 3%–3.5% of live weight and 50% of blood. This is an unavoidable loss which is necessary for meat quality and to be palatable. Sticking allows maximal blood removal. (Cockram, 2014; Fernando, 1992)
Poultry Cross contamination. Separate baskets washing area from slaughter.
Scalding Poultry Drowned alive chickens in blood or in scalding hot tunnel.Low standard quality meat.Cross contamination and high bacterial load.Blood loss.Short shelf life. Reduce the line speed of slaughter to avoid presence of feather in further process.Coordination of carcass flow and production lines so that adequate birds are present to make maximum use of personnel and equipment.Special bleeding rails and channels for collecting blood free from admixture with feather. (Pedersen et al., 2016; Sams and McKee, 2001; Smith, 2014)
Skinning Livestock Cattle are laid in a cradle for mechanical skinning by hide pullers. The animal should not be in contact with the floor.Hide should be removed such that be folded, preventing cross contamination. (Small et al., 2005; Tan, 2008)
Evisceration Livestock Contamination by faecal and abdominal pathogens, dirty feet and skin. Pre-evisceration water washes with acetic acid (1.6%–2.6%).Clean butchers tools such as knife and axes and sanitation of carrier, floor and walls frequently. (Bacon et al., 2000; Wagude, 2007)
Poultry Cross contamination.Skin tears in the thigh and breast regions, broken wing, leg, and rib bones.Loss in offal and defects in feet such as dark pigmentation or food pad lesions.Rework. Picking machines should not be adjusted too close to the bird.Do not manually transfer birds to evisceration line.Washing and avoiding intestine cut resulting in fecal and bacterial contamination.
Chilling Livestock Weight loss.Toughening. Monitor temperature and moisture.Avoid immediate chilling after slaughter to prevent toughening. (Devine et al., 1999; Sams and McKee, 2001; Yu et al., 2005)
Poultry Washing and chilling effects.Dark color which is usually taken as a sign of thawed and slow refrozen poultry meat.High bacterial load. Regulate water absorption by time and temperature.Use limited amount of chlorine as an antimicrobial agent in product contact water such as chiller.
Packaging Poultry Toughening.Aging.Weight loss or spoilage. Proper aging for at least 4 hours after death or 3 hours after exiting the chiller under refrigeration.Using oxygen scavengers, moisture absorbers, temperature compensating, antimicrobial packaging, aseptic packaging and sous vide. (Rouger et al., 2017; Zhu et al., 2014)