Myrtle fruit (Myrtus communis L.), a member of the myrtle family, is a well-known medicinal and fragrant plant. This includes two or more genera of one species, in its entirety. Fruit-3 cm long and 1 cm long, an elliptical evergreen tree. Its leaves are numerous, long and green in color. Flowers are solitary, white, located in the leaf axils (Alipour et al., 2014; Jabri et al., 2018a).
       
The therapeutic and physiological properties of myrtle berries are strongly due to their high level of bioactive secondary metabolites. The most important of these antioxidants are anthocyanins which provide better protection against the oxidation process along with antimicrobial and anti-inflammatory actions. Similarly, the chemical composition of berries is a combined mixture of an essential oil, organic acids and tannins. The berries themselves are high in soluble carbohydrates, ascorbic acid (vitamin C), vital minerals and pectin-aiding better digestive function. Myrtle berries are highly enriched in bioactive compounds, primarily anthocyanins demonstrating biological functionality with antioxidant, antimicrobial and anti-inflammatory activity, essential oils, organic acids and tannins. Besides pectin, which has a prebiotic effect (Mohammadi et al., 2021; Yegin et al., 2022; Sirivella et al., 2025), the berries also include sugars, vitamin C and necessary minerals.
       
Cheese is among the most significant dairy product. It is produced by causing milk proteins (casein) to coagulate using bacterial starters or enzymes. Due to its high content of high-biological-value proteins and essential minerals, it possesses special nutritional properties. Due to its physicochemical stability, it can be transported or stored easily and thus is a critical component of the global food systems. However, cheese is a good medium for unwanted microbes to grow on it which increases its biological spoilage and lowers down its quality as well as safety on consumers. Due to this technical trouble, research has been consequently oriented to find natural active compounds as potential alternatives for chemical preservatives. Since then, plant extracts and essential oils have exhibited considerable efficacy against pathogens and preserving products (Kim et al., 2019; Hammam et al., 2020; Sheet et al., 2026).
       
Studies concerning the evaluation of dairy technology involving the natural bioactives derived from plants have centered on their innovative technological incorporation into them, along with their functional and biological interactions occurring following food matrixs’ copresence (Abdel Fattah  et al., 2022). The well- known technical approaches exist to add plant parts, spices or extracted volatile oils in the manufacturing of cheese that enhances its sensory and chemical properties (Granato et al., 2018).
       
The research gap covers the still unresolved problem of rapid spoilage created by bacteria in soft cheeses and the growing economic need to replace chemical preservatives with safe bioavailable ones. Myrtle is widely used as an antioxidant and antimicrobial in laboratory conditions; however, there are no scientific data evaluating the impact of its direct application at different concentrations on the chemical and sensory characteristics of fresh cheese and how it can allow to meet a compromise between extending durability while preserving flavor acceptability among consumers. This study aimed to assess the potential of myrtle fruit powder as a natural preservative of fresh cheese for 21 days in storage through decreasing of microbial loads, monitoring chemical composition changes and sensory quality.

Preparation of myrtle ground
 
Preparing myrtle powder is a multi-step process that begins with rinsing the berries in distilled water to remove any dirt. Next, they are air dried at 40°C for 24 hours, preventing the degradation of heat-labile compounds. Next, the dried berries are ground into a fine powder, greatly increasing their surface area. Finally, the powder is placed in airtight glass containers and stored at 4°C to maintain chemical stability and prevent oxidation.
       
The ground myrtle fruit was obtained as shown in the Fig 1:


 
Cheese manufacturing and testing
 
Soft cheese was manufactured from cow’s milk according to the method described by Fox (2017), with some modifications. The addition of dried myrtle fruit powder at a concentration of 0.5 g per 100 g of soft cheese was used, designated as treatment (T1) and the addition of ground myrtle at a concentration of 1 g per 100 g of soft cheese was used, designated as treatment (T2). The two treatments were compared with a control sample, designated as (T0). The following tests were conducted:
       
Standardized international protocols are used for chemical tests that help figure out the basic parts of the cheese sample. We used the Subramanian and Rodriguez-Saona (2010) to guess the moisture content, the Lee and Kim (2008) to accurately measure the fat content and the AOAC (2012) to guess the protein content by multiplying the nitrogen content by the dairy conversion factor of 6.38. For the mineral content, the ash content was calculated using the Marshall method (2010) and the pH was measured at 25°C using the method of Larionov et al., (2020) by mixing equal parts of the sample and distilled water to make sure the results were correct.
       
Total bacterial counts and coliform counts were estimated using nutrient agar and MacConkey agar, respectively, according to Raquib et al., (2021), with incubation at 37°C for 24 hours. Total fungal counts were estimated using the casting method with PDA medium and incubation at 25°C for five days (Frank and Yousef, 2004).
       
The sensory evaluation of the cheese was conducted by ten evaluators (5 men and 5 women) from the Department of Food Science, College of Agriculture and Forestry, University of Mosul, using the Khalaf (2011) questionnaire, which assessed taste, color, aroma, texture and consistency.
       
We used a completely randomized design (CRD) with three copies of each treatment to make sure the results were correct and to reduce the chance of making mistakes during the experiment. We used the advanced software SAS (2012) and Duncan’s Multiple Range Test to compare the means of the treatments at a significance level of P<0.05.

Chemical content
 
The data in Table 1 show a trend of decrease in moisture content throughout most of the storage period and such decrease seem to be considerable on all treatments. The statistical differences between the later stages (days 14, 21) and the first stage was significant with no significant differences by the first stages. The control treatment (T0) had the highest moisture (60.50%) on the first day, whereas this number decreased gradually with treatment T2 on day 21 which had the lowest moisture value (56.50%). The drop in cheese pH (0.41) was explained scientifically based on osmotic property and protein network throughout the process of adding myrtle berry powder into the initial cheese mixture, this conforms with the work of (El-Sayed  et al., 2025) when different plant powders are used. These additional fibers and solids facilitate syneresis, which is the separation of whey. It allows the whey to leave and evaporate from the cheese easier. Powder particles also function as physical substrates that promote curd cohesion and gratifiy the expulsion of free waterwhich, together, can also clarify why cheese with added plant powders hold lower moisture compared to the control samples. These findings replicate those by Ribas et al., (2019) in their work regarding the influence of vegetable-derived additives on the textural characteristics of cheeses.


       
Table 2 the protein content results, apparent in treatments T1 and T2, showed a statistical difference determined by the storage time. The first phase (days 1 and 7) showed stable values in a relatively narrow range, which then increased slowly, reaching a maximum on day 21. The protein content was the highest value shown for treatment T1 at the end of the storage period (17.19%) with primary value treatment (T2) at the beginning of the experiment (17.90%), with this result confirming previously reported findings by Bosnea et al., (2020) who stated that soft cheese enriched with Spirulina platensis has a higher protein value. This with gradual rise in protein concentration is explained by continued evaporation of moisture from the samples till the total solids including protein becomes more concentrated. Similarly, the differences in the stability of the values in treatment T1 illustrate the importants of bioactive compounds in myrtle berries. Phenols and terpenes act as antioxidants and microbial inhibitors by nature (Shahidi and Ambigaipalan, 2015), limiting the activity of proteolytic enzymes produced by microbes and of importance in retaining the integrity of protein structures and averting quality deterioration during storage.


       
Table 3 influence from treatments on values measured during different storage periods (T0, T1 and T2); values followed by different letters in the columns represent significant difference (p<0.05) of cheddar cheese fat percentage. Fat values steadily increase over the course of days for all treatments, peaking on day 21. On first day T0: 19.44% and T1 19.68% and on day seven both 19.79, indicating that no significant difference between each treatment for first and seventh day. This means that these two treatments had similar initial effects at the start of the storage period. However, the first day (18.98%) and the seventh day (18.79%) effect of treatment T2 was less than that for the other two treatments, which indicates T2 had a different effect at the initial treatment stage. Nevertheless, by 14^th and 21^st day the effect of the treatments seems to visually separate; by reflection 21^st day all treatment groups have different growth. The day 14 was characterized by the minimum value (20.49%) registered for treatment T2, whereas the values recorded for treatments T0 and 1 were similar (21.52% for T0 and 21.49% T1). Lipid resultsThe highest associated with lipid saved in T was 24.17% of all the treatments for time 21 while the T1 and T2 were one hair distance with 23.32% and 23.36% respectively, These total results slim with the ones from Hashish et al., (2018) who observed that incorporation of grape seeds increased fat content in soft cheese. It should stressed that the stability or variability of measured lipid values throughout the storage time are differentially affected by each treatments in the present study, given that a global increase of values regarding with the increasing of storage time was verified and also significant differences were noted in pairwise comparisons by treatments at the latter periods. Because ground myrtle is antibacterial, antioxidant and has water holding capacity abilities, as well as the propensity to interact with product ingredients, it serves as a type of preservative. And that, in turn, could have an impact on the future supply of cheese ingredients like fat. Some active phenolic compounds from myrtle studied by multiple authors, such as gallic acid and myricetin, are well known natural antioxidants (Farag et al., 2020), so with the increase of myrtle in the composition, the antioxidant activity of the product was higher.


       
The results in Table 4 demonstrate that the final ash content determined remained very constant for all treatments evaluated (T1 and T2) during the evaluation period (days 1-21). All values were not significantly different and consistently stayed within a close range of 3.19% to 3.22%. Scientifically, this stability is because ash is the accumulation of inorganic matter. These inorganic compounds have relatively stable chemistry and do not decompose or interact with enzymatic processes the way proteins and fats do when stored. Also, those values did not vary after the incorporation of myrtle powder pointed out that the amount added was not enough to change the mineral balance of the elaborated product. That information correlates well with what Nielsen (2017) states regarding the stability of minerals in food upon different storage methods and confirms the presence of minerals in the cheese.


       
Table 5 shows how treatments (T1 and T2) can affect the cheese pH values during storage periods. There was a slow decline up to days 1, 7 and 14 and a sharp rise on day 21. The values were similar for all treatments on day 1 (6.30-6.31), but decreased to 6.18-6.19 on day 7 and to 6.10-6.11 on day 14, the lowest value of the period of evaluation. This is because of the action of lactic acid bacteria. The pH increased significantly on day 21, up to 6.30 in one of the treatments, whilst the highest values were recorded for T1 and T2 (6.50 and 6.70, respectively). This is what Anwar et al., (2016) indicated: that extracts of myrtle and plants in general contribute to preventing food spoilage due to their antioxidant and antimicrobial properties.


 
Microbial content
 
Table 6 shows the impact of treatments T0, T1 and T2 on the microbiological evolution of cheese during storage periods. The numbers of total bacteria largely rose with storage time, but there were no significant differences on day 1 between cultured dilutions, whilst marked changes were observed on days 14 and 21. In day 21, the total bacterial count was 2.02 CFU/g, which is less than T0 with a value of 2.96 CFU/g (day 14). This results indicate the inhibitory effect of myrtle powder; as for treatment T1 and T2, supplemented with myrtle powder compared with control treatment T0 showed lower bacterial counts during storage period of most part. In the two storage periodic T1 and T2, treatment with no coliform were founded; however, in tree tests of T0 their concentrations increased to 1.00 (p<0.005), 1.30, 1.30 and were recorded with a minimum on day one and maximum on day twenty-one respectively which are consistent with Derbassi et al., (2022). who described that extracts of Arbutus unedo leaves caused a decrease in the microbial load in cheese.


       
Until day 7, no fungal growth had been identified in any of the treatments (data not shown), while fungal growth was only detected in the T0 treatment at 14 days. At day 21, for treatments T0, T1 and T2 the fungal counts were of 1.69, 1.47 and 2.30 CFU/g; respectively, being thus higher values observed in control treatment. Authors attributed this effect to the active compounds from myrtle (tannins, flavonoids and phenolic compounds with antimicrobial activity), which not only reduce microbial load but also could improve microbiological characteristics of the cheese and prolong its shelf life (Nwafor et al., 2024).
 
Sensory evaluation
 
The sensory evaluation results in Table 7 demonstrate the significant superiority of the treatments enriched with myrtle extract in preserving the organoliptical (sensory) characteristics of the cheese over time. While the control sample experienced a sharp decline in total points from 96 to 84 due to deterioration in taste and texture, the treatment with 1% extract (T1) maintained exceptional quality, scoring 91 points on day 21.This scientific superiority of treatment T1 is attributed to the rich content of phenolic compounds and flavonoids in myrtle extract, which act as a dual defense. They function as natural antioxidants, preventing fat rancidity and flavor changes and as antimicrobial agents, inhibiting the growth of spoilage microorganisms that negatively affect texture and color. This vital role of the extract contributed to slowing down the chemical and biological reactions responsible for spoilage during storage, which enhances consumer acceptance of the product for longer periods and is consistent with what was confirmed by the studies of Nikmaram et al., (2018) regarding the ability of plant extracts rich in phenols to extend shelf life and improve the sensory properties of foods.

The present research report quantifies that 1 gram dose of Myrtle leaf powder (Myrtus communis) (T2) is a novel and new natural source available in market to improve quality of soft cheese and to enhance soft cheese shelf life. The addition was successful in inhibiting microbial growth, especially coliform bacteria. The moisture content was reduced in the wheat flour end products, which provided a barrier to microbes, ensuring stability of chemical traits such as ash and pH, as well as enabling increase of protein content. Sensory quality was initially better in the control sample, but fortified treatments had improved sensory stability and taste and texture scores that did not deteriorate as quickly as those of the control sample over a 21-day period. Plant phenols have various antioxidant and antimicrobial properties to provide this. Myrtle’s powder should be added during fresh cheese making to improve nutrition and safety in the same time period without sacrificing palatability in longtime.

All authors declare that they have no conflict of interest.