###### Abstract  
Walnuts are highly valued for their rich nutritional content, but their quality degrades during storage due to oxidation and other quality reducing processes. This study investigated the use of bioactive compounds extracted from walnut pomace, a by-product of walnut oil production, to develop an edible coating that extends the shelf life of 'Milotai 10' walnut kernels. Walnut kernels were stored for eight months in four different packaging materials (PE, PP, MPP, PLA) and three treatments were used (air or without treatment, nitrogen gas, and walnut pomace extract coating). The effects of these combinations on walnut quality parameters, including polyphenol content, vitamin E, fatty acids, peroxide value, and color, were analyzed. The results show that the combination of metallized polypropylene packaging under nitrogen treatment or with atmospheric air and walnut pomace extract (MPP-A-E+) best preserves walnut quality, making it a promising option for extending shelf-life. walnut; packaging; edible coating; PE (polyethylene); PP (polypropylene); MPP (metal-ilized polypropylene); PLA (polylactic acid); fatty acids; polyphenols; tocopherols 2024 1 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 0000 000 000  
of the kernel mass [11]. Additionally, they are a rich source of polyunsaturated essential fatty acids (PUFAs), predominantly omega-3 and omega-6 acids. The ingestion of these acids has been associated with a reduction in LDL cholesterol and an increase in HDL cholesterol [12]. For this reason, the consumption of walnuts has been demonstrated to assist in the prevention of cardiac arrhythmia, cardiovascular disease, gallstone formation, and the action of free radicals [13; 14]. The walnut kernel possesses a distinctive chemical and nutritional composition. Extracts prepared with different parts of the walnut have been demonstrated to possess a range of beneficial properties, including anti-inflammatory, blood purifying, anticancer, cleansing, and detergent effects [15]. The main parts of the tree that have been extensively studied are the walnut fruit, branch, leaf, shoot, and bark. Investigation showed that the aqueous extract of walnut bark protects mice against cyclophosphamide-induced biochemical toxicity due to the polyphenols [16]. According to [PERSON] et al. [17] the effects of subcritical water extraction parameters on the total polyphenols, flavonoids, and antioxidant activity of walnut bark extract were determined. The total polyphenol content extracted from the bark of the walnut ranged from 128.3 to 192.1 mg (GAE)/100 g (DM), varying according to the experimental conditions. The highest polyphenol and flavonoid contents, along with the antioxidant activity, were observed at a temperature of 131.6 \({}^{\circ}\)C, a raw material fraction size of 0.9 mm, and a process duration of 10 min, using subcritical water extraction. The chemical and physical properties of walnuts are influenced by storage conditions. The deterioration of walnuts is attributed to the advancement of lipid oxidation, which generates an unfavorable, rancid taste, off-flavors, and browning reactions during storage [18; 19]. The process of lipid oxidation is influenced by several factors, including the temperature at which the substance is stored [20], the presence of light [21], and the levels of oxygen present [22]. The chemical composition of walnuts is significantly influenced by their processing and storage conditions, and the types of packaging materials and treatment given at the time of packaging may also affect it [23; 24; 25]. The impact of packaging with distinct modified atmospheres on the lipid oxidation of nuts was investigated in several studies. These studies employed a range of techniques, including nitrogen and carbon dioxide (CO\({}_{2}\)) flushing, vacuum packaging, and oxygen absorber systems [26; 27]. Walnut oil is produced by press extraction of walnut kernels, and the by-product of the process is walnut oil cake, which is also rich in polyphenols.