The one-humped camel: The animal of future, potential alternative red meat, technological suitability and future perspectives

Expressed juice

The importance of moisture in camel meat is in its marked effects on its processing potential, quality characteristics and shelf life optimization during storage. Meat cuts with low water holding capacity (WHC) are drier and would lose more weight during refrigeration, storage, transportation and marketing. Result of this, loss of minerals, salts and vitamins (Kadim et al. 2013). In meat, juiciness and tenderness are closely correlated. The more tender the meat, the faster the juice is released by chewing it. Meat with higher pH value has a greater WHC than that with a low pH value; often referred to as: dark, firm and dry (DFD), and pale, soft, exudative (PSE) meats, respectively (Liu et al. 2021).

Tenderness

Meat tenderness is often determined by muscle characteristics, collagen content and its solubility, post mortem glycogen concentration, proteolytic enzymes content and more likely in the enzyme/inhibitor ratio, a parameter reflecting the efficiency of the proteolytic systems (Nair et al. 2019). Reports that camel meat is less tender than other animals are likely due, at least in part, to the higher average age of slaughtered animals, mainly obtained from old animals (aged >10 years). A number of studies have shown that Warner–Bratzler–Shear Force (WB-SF) values increase with animal age. The values reported in the literature, indicate higher values than those reported for beef.

Kadim et al. (2006) suggested that the shear-force value from aged camels (8 years) was 48% higher than that from young camels (1–5 years). The WB-SF values for various camel muscles were determined by Kadim et al. (2013). The infraspinatus, triceps brachii, longissimus thoracis muscles have significantly lower shear-force (6.3–6.7 kg) values than semitendinosus, semimembranosus, and biceps femoris muscles (9–12.9 kg), which might be due to less connective tissue. Suliman et al. (2019) reported a similar result.

Consumer acceptance of identified individual muscles should be assessed with the aim of developing positive marketing strategies towards consumer perception of camel meat. However, evidence suggests that camel meat tenderness is not significantly different from beef if it is slaughtered at the same ages (Kadim et al. 2011). Many exogenous enzymes have the capacity to degrade muscle proteins, leading to this effect, a significant degradation of the miofibrillary system, and consequently, a better sensory qualities of obtained meat (Bagheri Kakash et al. 2019). The MFI of old camels (6 years) was lower than youngers (<3 years) (Al-Owaimer et al. 2014). The authors observed a strong relationship between physical disruptions of the myofibrils and the tenderness. MFI is one of the most widely used methods to determine post mortem proteolysis in meat of various species. This index is a very useful indicator of meat tenderness. Smili et al. (2022) reported that MFI of Algerian Sahraoui dromedary meat was significantly affected by both slaughter age and post mortem period. The same authors confirmed that the 30-kDa band is a proteolytic product of Troponin-T in camel longissimus lumborum muscles. Soltanizadeh et al. (2008) observed the appearance, on the third day of storage, of a 30-kDa band in camel meat which was linked to the higher degree of proteolysis. Therefore, various methods have been developed for tenderizing camel meat. Abdel-Naeem and Mohamed (2016) found that addition of Zingiber officinale extract in camel meat burgers resulted in higher MFI. The tenderness of meat can also be improved by the use of exogenous enzymes which break down muscle proteins including connective tissue. Nevertheless, the action of proteolytic enzymes on collagen is limited, which makes them less useful for old camels’ muscles with high collagen content. Recently, plant proteases have been used as a sustainable manner to improve the texture of tough camel meat and to develop functional meat products that contain bioactive molecules with antioxidant activities (Gagaoua et al. 2021). From another perspective and to overcome the problem of toughness in camel meat, Smith et al. (2016) showed that whatever the age of the animal or the sex, electrical stimulation (ES) could drastically decrease the hardness of camelid meat. ES of carcasses at 20 to 100 V is a proven method to prevent fibers cold shortening and thus to improve tenderness of meat (Polidori and Vincenzetti, 2017). The effects of post mortem ES (90 V)/20 min was assessed by Kadim et al. (2009), authors found that muscles from young camel were not affected by cold shortening and ES had a significant effect on meat quality attributes. Muscles from electrically non-stimulated carcasses have a higher WB-SF value (9.47 kg/cm²) compared to those of stimulated carcasses (6.97 kg/cm²) (Kadim et al. 2009).

Carcass suspension methods can also have a direct effect on meat tenderness. Indeed, the “tenderstretching” mode favored the tenderness of camel meat (Smith et al. 2016). The combination of ES/tenderstretching further promotes tenderness of camel meat (Biffin et al. 2020). The key mechanism by which ES improves tenderness is by rapidly decreasing the concentration of adenosine triphosphate (ATP), which reduces the potential for myofibrils to contract and cold shortening if post mortem carcasses are immediately refrigerated.

Color

Camel meat is described as “raspberry red” and sometimes brown in older animals (due to a higher concentration of myoglobin: Mb) (Kadim et al. 2013). Abdelhadi et al. (2013) reported that there are differences in the color of camel meat with a seasonal effect linked to the diversity of animal feeding throughout the year. It was significantly darker red in autumn compared with summer and less yellow in autumn than in summer and winter. In addition to season’s differences, storage temperatures were reported to affect muscle biochemical characteristics and color. The color characteristics of camel meat can be influenced by the post mortem storage period and the type of muscle (Suliman et al. 2019). A high redness (a*) color component was associated with a lower lightness (L*), which might be due to an increase in Mb content (Maqsood et al. (2015a). However, meat from older camels have lower L* (darker) and higher a* (redder) than that of younger camels (Kadim et al. 2006). Post mortem proteolysis increases light scattering properties of meat and thereby affects L*, a* and b* (yellowness) values (Hughes and Anderson 2020), which is also directly related to the pH_u. Meat proteins have an isoelectric pH (pH_i) of 5.5. This results in open muscle structure and as a result lighter scattering between the myofibrils, which makes the surface of the meat lighter. It is obvious that during the retail display, the meat surface color is unstable. This phenomenon is due to several factors such as, post mortem biochemical changes in protein and lipid fractions of the meat, surface microbial overgrowth, oxidation of lipids and Mb and finally, the phenomenon of photo oxidation due to the fluorescent tube installed in the refrigerated display cases (Djenane et al. 2001, 2003). In the USA, an average of 2.55% of total red meats sold are discarded annually due to discoloration (13.4 million kg, the equivalent of USD 3.73 billion loss) (Ramanathan et al. 2022).

Strategies for preserving color of camel meat were the application of post mortem low voltage ES. Abhijith et al. (2020) reported that meat from electrically stimulated carcasses, have a brighter red color than meat from -non-stimulated carcasses. Using appropriate packaging and cold storage conditions (vacuum, modified atmosphere packaging (MAP) and active packaging) can play a major role in color enhancement of meat during storage (Nerin et al. 2006; Camo et al. 2011; Lammi et al. 2018; Ait Ouahioune et al. 2022a). Maqsood et al. (2015b) reported that camel meat total haem content expressed as haematin was 92.3 mg/g which is higher than what was found in beef (76.16 mg/g). However, the presence of a high haem content could contribute to fast meat pigment oxidation during its refrigerated storage. Average Mb contents in camel meat was found to be 7.16 mg/g (Maqsood et al. 2015a). In contrast, Gheisari (2011) reported 3.64 mg/g. This difference could be due to several experimental factors such as part of the carcass, solvents and extraction conditions. In general, the quality of camel meat has been assessed using traditional conventional methods, and it will be important for the camel sector to take into account the new technologies already applied to beef.

Processing technologies

Camel meat has been processed into burgers, cured or cooked ham, kebabs, meatballs, patties, mortadella, merguez, sausages, and shawarma to add value (http://www.australiancamelindustry.com.au). Australian processed camel meat has been accepted as international traded meat products (Wu et al. 2011). It is now exported to Canada, China, Europe, Saudi Arabia and the USA. The potential of camel meat has received increased attention in recent times. In this context, Kargozari et al. (2014) compared the fatty-acid and volatile-compound profiles, sensory qualities and the physicochemical of dry sausages (Sucuk) made from camel meat and hump fat with sausages made from beef and beef fat and from a mixture of both. The authors suggest that the physicochemical properties and some textural attributes of camel meat sausages were comparable to those of beef. Nerveless, the flavor components were quantitatively much higher in camel sausages. The same authors concluded that camel meat can successfully replace beef in sausage manufacture.

The growing concern of consumers regarding the food health and safety issues has led to the development of products that promote health and well-being beyond its nutritional effect. Fermented meat products can be considered as relevant matrix for the delivery of bioactive molecules with potential health benefits (Mejri et al. 2017b; Ayyash et al. 2019). In a comparative study, Kargozari et al. (2014) found that fermented camel sausages exhibited greater resistance to lipid oxidation (lower thiobarbituric acid reactive substances: TBA-RS) during storage compared to beef sausages. These authors obtained an ω-6/ω-3 ratio of 6.22 for beef sausages and 2.95 for camel sausages. This indicates that camel sausages fit perfectly into the recommendations for this ratio (BDH, 1994). Abdel-Naeem and Mohamed (2016) found that addition of ginger (Zingiber officinale) and papain (Carica papaya) extracts in camel burger resulted in improvement of the lipid stability and significant increase of sensory scores of treated burgers during storage. Gagaoua et al. (2021) showed that marinade with plant proteases has been used to improve the texture of tough camel meat. This can be a valuable strategy to develop locally tender camel and healthier products. Maqsood et al. (2015b) studied the effect of phenolic compounds such as tannic acid and catechin on sensory quality and fatty acid profile of camel meat during storage, and found that incorporation of these compounds improved sensory scores and fatty acid profile. Furthermore, authors suggest that tannic acid and catechin could prevent protein breakdown in chilled ground camel meat, which was most likely due to their antimicrobial and antioxidant activity. Despite the low cholesterol content of camel meat, the salt curing process can induce significant amounts of cholesterol in the final products (Mamani-Linares et al. 2014). To avoid this problem, solar drying under the open sky of camel meat without salting was carried out by Chaouch et al. (2018).

The growing demand for Halal gelatin, and the rejection of gelatin from a mainly porcine source have encouraged scientists to search for alternative sources such as camel skin (Asif Ahmed et al. 2020). Recently, Al-Hassan (2020) demonstrated that gelatin could be extracted from camel skin as a promising source of Halal gelatin.

Packaging technologies

The evolution of modern retail outlets with better packaging, labeling, and cold chain facilities will address the drawbacks of the current situation in the camel meat sector. Referring to packaging technologies, very little data are available on the application of innovative techniques in camel sector (Table 1). Microbial spoilage associated with color change and lipid oxidation are the critical factors limiting shelf-life and consumer acceptability of stored camel meat (Maqsood et al. 2015b). Haem pigment is known to be potent catalyst of lipid oxidation in muscle foods. With increasing storage time, damage to haem pigment results in the release of ferrous (Fe⁺²), which can accelerate lipid oxidation (Gheisari, 2011). Its role as catalyst of lipid oxidation is because is capable of catalyzing the production of reactive oxygen species (ROS) such as superoxide anion (O₂^•−). This process is frequently explained by the Fenton reaction. Alkyl radicals can be formed as a result of the reaction of O₂^•− with fatty acids and hence the onset of lipid oxidation. Moreover, O₂^•− could be transformed into hydrogen peroxide (H₂O₂) by dismutation, which react with ferrous iron (Fe⁺²) to produce the hydroxyl radical (OH•).

Djenane et al. (2020) reported that high oxygen (80%) modified atmospheres associated with olive leaf extracts (Olea europaea Subsp. laperrinei) and nisin, a polycyclic antibacterial peptide produced by Lactococcus lactis can be used as a strategy to retain the redness of camel meat during retail display. Jouki and Khazaei (2012) found the lowest lipid oxidation degrees for vacuum packaged camel meat compared to anoxic MAP (60% CO₂; 40% N₂) and air packaged meat during chilled storage, and concluded that vacuum packaging can be used as an effective strategy against deleterious consequences of lipid oxidation. In this same perspective, Maqsood et al. (2016) reported that the shelf life of chilled vacuum stored camel meat could be extended to 18 days compared to wrapped samples.

Modern food packaging provides a way to make food safe, reliable, shelf-stable and clean. However, the packaging, without departing from its irreplaceable role in food preservation, is accused today of polluting food and polluting the environment (Ncube et al. 2020). Unfortunately, most food packaging is designed to be single use and is not recycled. The world's population continues to grow and so do natural resources demand. Consumers not only care more and more about what they eat, they are also more concerned with the packaging of the food they buy. This increased focus on environmentally friendly consumption leads to the development of more sustainable business practices and a low-cost circular economy (Baghi et al. 2022). Because of the inability of plastics to degrade, the environmental pollution it causes is a major global concern (Chamas et al. 2020). To overcome this serious problem of plastic waste, the modern food industry requires new and effective approaches to preserving perishable food products. The ideal packaging should have a lower carbon and water footprints, be biodegradable and/or compostable, uses waste or by-products, is eco-designed and safe, and has the right preservation properties to minimize food waste (Moshood et al. 2022; Ait Ouahioune et al. 2022b). The incorporation of bioactive molecules (antimicrobial and antioxidant) in packaging materials can remarkably help extend the shelf-life of perishable foods by retarding microbial growth and reducing oxidation (Djenane et al. 2016). Nanotechnology can also play a fundamental role in the meat industry, from processing, preservation to packaging of fresh or processed meat products (Lamri et al. 2021).

Preservation and extended shelf life

Over the past decade, meat products commercialization strategies have notably changed all over the world (Juárez et al. 2021). However, as a result of increasing demand for fresh and ready-to-use meats, a need has emerged for adequate preservation techniques to maintain their quality and safety. These technologies include chilled storage, vacuum and MAP, biopreservation, active and biodegradable packaging, and their combination (Figure 2).

Figure 2. Factors affecting camel meat quality and safety and its preservation.

Camel meat is rich in Mb (haem protein) and several authors have reported the pro-oxidant effect of this protein in its oxidized state on lipid oxidation (Maqsood et al. 2015a,b). This makes camel meat more susceptible to oxidation of lipids and therefore to the development of unpleasant odors (off odor) and can limit its shelf life during storage. To overcome this problem, the use of antioxidants is one of the main strategies to extend the shelf life of camel meat (Djenane et al. 2020). Nowadays, frozen storage of meat is broadly utilized to extend its shelf life over one year (Dang et al. 2021). Additionally, most previous studies do not consider the impact of freezing and cooking on varying nutrient amounts in camel meat. The most important phenomenon observed, when cooking meats, is the thermal denaturation of muscle proteins (Sayd et al. 2016), that may cause loss of juice displaying a direct impact on the nutrient content of cooked meats.

Recently, novel strategies are directed towards the use of natural bio preservatives ingredients, which can minimize lipid and pigment oxidation, and off odor development with increase of the color stability and consequently the acceptability of camel meat. Therefore, the use of natural plant-based antioxidants, especially phenolic compounds, could be an effective way to extend the shelf life of stored camel meat (Djenane et al. 2020). Thus, plant extracts not only possess antioxidant activity, but also antimicrobial activity against spoilage bacteria and harmful pathogens (Djenane et al. 2012a,b).

It has been reported that camel meat treated with tannic acid and catechin had lowest TBA-RS value, indicating strong inhibitory effect on lipid oxidation during nine days of storage (Maqsood et al. 2015b). Gheisari and Motamedi (2010) found that the presence of high activities of endogenous antioxidant enzymes such as catalase and GSH-Px could lead to a significant decrease in lipid oxidation during camel meat storage. The PUFAs content in camel meat is still desirable for human consumption; unfortunately, these FAs are likely to be susceptible to rapid oxidation. It has been shown that a level of lipid oxidation in the range of 1.5 to 2 mg/kg of malondialdehyde in camel meat caused its rejection by a trained panel for the unpleasant off odors (Djenane et al. 2020). Studies have shown that in some camelids, the level of lipid oxidation remains low (Smith et al. 2019). This is due to the probably high levels in fat soluble vitamins such as vitamin E and other antioxidants reported in camel meat, which is the result of its supply of aromatic and medicinal herbs from arid regions. Maqsood et al. (2015b) investigated the effect of phenolic compounds on microbial quality of camel meat during refrigerated storage. The authors suggested that phenolic compounds were effective in inhibiting microbial growth in meat by chelating specific metal ions essential for microbial growth. In previous study, Djenane et al. (2020) found that higher oxygenated MAP (80% O₂) associated with Olea europaea extracts treatment combined with nisin can be a promising tool and constitute a relevant strategy to control microbial growth and oxidation phenomena in camel meat. Similarly, Jouki and Khazaei (2012), using an anoxic MAP (60% CO₂ + 40% N₂) combined with refrigeration storage (4°C) have obtained significant improvement in physicochemical and sensory properties of camel meat within three weeks of storage. Recently, Yehia et al. (2021) reported that the use of combined natural biopreservative agents (Citrox and chitosan) can be a promising tool to control Campylobacter jejuni growth and to preserve packaged camel meat even at abuse refrigeration (10°C) storage. A combination of essential oils (EOs) components like carvacrol, thymol or cinnamaldehyde with the yogurt-based marinade exerts a lethal effect against Escherichia coli O157: H7 and Salmonella spp. without significant changes in the sensory characteristics of the cooked camel (Osaili et al. 2020b). Mentha spicata EO was incorporated at different concentrations (0.5 to 1.5% v/w) into camel meat to evaluate its antibacterial activity at refrigerated storage. The final microbial population decreased until 4 log cfu/g. Moreover, during storage, peroxide value (PV), total volatile basic nitrogen (TVBN) remained lower in treated compared to control samples. Similarly, Khezrian and Shahbazi (2018) incorporated of Ziziphora clinopodioides EO in combination with Ficus carica extract into active packaging films, and found that packed meats exhibited better safety against Listeria monocytogenes and E. coli O157: H7. Sensory attributes were significantly enhanced in treated camel meat samples.

Camel meat remains an essential source of protein for arid region populations. Nonetheless, various traditional meat products have long been known in the region and prepared for family or religious feasts. For example, during the “Al Adha feast”, Muslim families ought to slaughter a whole camel to be shared equally between seven families. Surplus meat was then transformed into more stable products. This was achieved by combined treatments in an empirical application. However, the sanitary and hygienic importance, and the perishable nature of these products prompted public authorities to establish controlled slaughter structures. Strict compliance with good hygiene practices in slaughterhouses is therefore essential to prevent bacterial contamination of carcasses, with the aim of maintaining optimal meat quality, thus protecting consumer health.

Ecological harmlessness of camel meat production

The growing demand for meat cannot be met by conventional meat production alone, because 80% of all arable land is already used directly or indirectly for livestock production (https://ourworldindata.org/environmental-impacts-of-food), and this is unsustainable as it is, due to its large ecological footprint. By 2050, the world's population will reach around 10 billion people, according to a new report published by the United Nations Department of Economic and Social Affairs (https://population.un.org). A great challenge awaits policy makers and ensuring food security without compromising the main pillars of sustainability is one of the main objectives of the United Nations for sustainable development. In this optical, the camel sector must adopt sustainable practices in order to become more competitive (Faye, 2013). Compared to other species such as goats, cattle and sheep, camel is less destructive for the fragile pasturelands. Camel meat is therefore an ecologically friendly food. Camels also have a very efficient feed conversion rate. Nowdays consumers, especially in rich civilizations, tend to favor produces that are environmentally friendly; as a result, this is a very important attribute that needs to be promoted in favor of camel meat.

In arid regions, camel herds are often dispersed over large areas rather than clustered like cattle and sheep. However, camels eat only small amounts at a time and are considered one of the least overgrazing ruminants, unlike sheep and goats. Camel meat can consequently be produced economically compared with other competing meats. According to FAOSTAT, the worldwide meat production has been projected to be double by 2050 (http://faostat3.fao.org), due mainly to the increase in production and consumption, which is likely to intensify the freshwater crisis in the future. The virtual water content (VWC) for camel production has not been well investigated. Quantification of VWC for the camel production plays an important role in understanding the aspects of national water footprint (WFP) in arid regions and is highly needed to guide the allocation of livestock farming and optimize water use (Qasemipour and Abbasi 2019). However, the current changes in camel farming practices (the Bedouin system based on camel mobility called “H’mil” versus semi or intensive systems) based on intensification of the management could modify this conception. According to Chowdhury et al. (2017), the unit VWC of camel is 3.5- and 1.7-times the VWC for sheep and cow, respectively. One kg of cow and camel meat required 19.7 and 14.6 kg of feed supply, respectively. To my knowledge, there are no works on the carbon footprint and on the water consumption required for the production of 1 kg of camel meat. However, Faye (2013) found that the water consumption for producing 1 L of camel milk was multiplied by nine passing from 938 to 8601 liters of water per liter of produced milk. However, all these results remain to be confirmed by future other studies in different arid and semi-arid regions.

The economic potential of camel meat

Generally, in developed countries, meat production has significant impact on nearly all aspects of the environment, including climate change (https://ourworldindata.org/environmental-impacts-of-food). Beef is the most popular meat widely produced in the world. Unfortunately, it is also the most inefficient animal to produce meat in terms of the amount of input needed to produce it (Paris et al. 2022). Camel is considered a fundamental pillar of the national economy and food security for many countries in arid regions (Faye, 2013). Meat professionals see the still virgin camel market as a sure opportunity to do good business and participate in the development of rapidly changing agricultural and agri-food sectors. Camel meat has reduced production costs because camels are usually reared in arid regions. In these harsh environments, poor quality feed is the only source for camels and is not utilized by other domesticated species. As a result, camels can produce meat at a lower cost compared to cattle, goats and sheep. FAO projects the global meat production to more than double from 229 million tons in 1999 to 465 million tons in 2050 (http://faostat3.fao.org). The average meat consumption worldwide during 2015 was 42.14 kg per capita/year, while in 2019 it was 43.16 kg per capita/year. Thus, the increase in consumption between these years was 2.42%. In the total meat consumption was added beef, sheep, pig, goat, poultry and then other meats (camels, rabbits…). Meanwhile, the global population is also expected to further increase. This will drive up total worldwide meat consumption. Producing more meat to meet the problem of population growth means more animal feed will have to be produced, which also means more land and water will be needed. On the basis of these expected challenges, camel meat is presented as a potential substitute for other red meats because, among other things, camels require fewer resources in terms of land and water.

Camel meat demand in high-value export markets

Recently, more attention has been paid to the nutritional value of camel meat, with the aim of creating additional value for various camel meat products. Although the marketing systems for camel meat are not well organized. This causes failure in appreciating the importance of these products in contributing to the development of the camel sector. Camel milk, on the other hand, has been marketed and used as a processing aid in several European countries, in particular the Netherlands, Denmark and England. This culminated in 2013 when the European Community authorized the import of camel milk from the United Arab Emirates. This great popularity of camel milk is probably due to the prior knowledge of its nutritional value and human health benefits compared to the more widely consumed cow's milk.

The world’s Muslim population is expected to increase by about 35% in 20 years (2010–2030), by 2030, the global Muslim population is expected to reach 2.2 billion people compared with 1.6 billion in 2010. This huge increase in the Muslim population, coupled with the recent increase in popularity of camel meat in Australia and China, creates an unprecedented potential for camel meat.