## 1 Introduction  
Horse meat is less popular than other meats, such as poultry, pork, beef, and mutton, and accounts for only \(0.25\%\) of the total global meat production [1]. Horse meat is unique and has a global consumer base. It is characterized by lower cholesterol and fat content than other meats, with approximately \(20\%\) less fat than pork, beef, or poultry [2]. Additionally, owing to its high iron concentration and unsaturated fat content (over \(55\%\)), horse meat consumption may offer health benefits to humans [2]. It is known for its distinct flavor profile, which is lean with a slightly sweet aftertaste. Uncooked horse meat has dense fibers because it is typically obtained from retired horses, slaughterhed riding horses, or racing horses. Although this meat can be tough, it is rich in minerals and protein and low in fat because of the horse's unique diet [3]. These characteristics make horse meat an intriguing subject for culinary experimentation, especially when using advanced cooking methods, such as sous vide. The utilization of thoroughbred horses extends across diverse domains, such as horse sports, leisure activities, and tourism [4]. Concurrently, the unwanted horses are subjected to slaughter for meat consumption. Consequently, the inclusion of thoroughbred horses in this study is imperative, as it serves as a representative sample reflecting the broader horse industry. Sous-vide cooking is the process of cooking food at specific temperatures and durations within a thermostabilized vacuum-sealed bag. This method involves packaging the product in plastic bags with low oxygen permeability and high-temperature resistance and then cooking the products for extended periods in a thermally stable container at a constant temperature; afterward, the products are stored in a low-temperature condition or served immediately [5]. Vacuum-sealed low-temperature cooking methods have significant appeal to the food industry. This appeal is primarily due to the positive effect of the sous-vide cooking method. The sous-vide method, applied to beef, pork, and poultry, offers advantages such as increased process yield, leading to enhanced juiciness and improved flavor, aroma, color, tenderness, and microbial control, while minimizing nutrient loss [6]. Furthermore, vacuum technology has potential applications not only in the food service sector, which includes restaurants, catering, and food retail, but also in various industries, such as transportation (aviation, railway, and maritime transport), medical facilities (hospitals), healthy food markets, educational facilities (schools), and the military. Conventional cooking methods differ from the sous-vide method recommended by experts for specific meat types and cuts. Typically, experts advise using temperatures ranging from 58 to 63 \({}^{\circ}\)C for 10-48 h for pork, while the conventional cooking of pork often involves temperatures of 75-80 \({}^{\circ}\)C [7]. Previous studies have used temperatures span from 60 to 80 \({}^{\circ}\)C for 6-24 h on lamb [8] and from 45 to 65 \({}^{\circ}\)C for 4 h on beef [9]. Sous-vide cooking enhances the tenderness and juiciness in various cuts of meat, including pork, lamb, and beef [10]. The tenderness achieved through sous-vide cooking is primarily a result of protein denaturation at low temperatures, which weakens the connective tissue by solubilizing collagen and retaining water [11; 12; 13]. Vacuum-sealed food efficiently conducts heat and prevents lipid oxidation, loss of volatile compounds, and moisture loss, thereby improving food flavor during sous-vide cooking [14]. Previous studies have shown that sous-vide cooking improves the quality of beef [15], lamb [8], poultry [16] and pork [17]. However, there is limited scientific information regarding the effects of sous-vide cooking with variations in duration and temperature on horse meat.