## Results and Discussion
### Kinetics of Microbiological Data and Model Development/Validation  
The applied volume of \"_tsipouro_\" (40 mL) on the absorbent pad placed underneath the ground beef was decided after conducting preliminary experiments, following similar set up to the main experiment (namely 500 g ground beef, MAP, TVC, and colour measurements) (see Section 2.2) and testing \"_tsipouro_\" volumes of 20, 30, 40, and 60 mL combined with storage at 7 \({}^{\circ}\)C. Growth of TVC was delayed by increasing the applied volume of \"_tsipouro_\", resulting in 0 (20 mL), 2 (30 mL), and 5 days (40 mL and 60 mL) shelf-life extension (data not shown). However, the volume of 40 mL was eventually selected for the main experiment, because ground beef samples packaged with this volume showed more \"bloomed\" red colour compared to samples packaged with 60 mL \"_tsipouro_\". The changes in relative levels of spoilage association of ground beef packaged with absorbent pads supplemented with \"_tsipouro_\" or not (controls), were dependent (\(p<0.05\)) on storage temperature (Figure 3). This is also supported by the maximum specific growth rates (\(\mu_{max}\)), which significantly increased (\(p<0.05\)) with temperature from 0 to 12 \({}^{\circ}\)C, regardless of treatment and microorganism (Table 1). Higher temperatures also increased (\(p<0.05\)) the maximum population density (\(N_{max}\)) of  
Figure 3: Growth curves of **(a)** LAB, **(b)** pseudomonads, **(c)**_B. thermosphacta_, **(d)** yeasts and moulds, and **(e)** TVC in ground beef (500 g) packaged with absorbent pads supplemented with a total volume of 50 mL _“tsipouro_” (40 mL under the ground beef piece and 10 mL under the labelling, facing the headspace) under 80% O\({}_{2}\): 20% CO\({}_{2}\) during isothermal storage at **(I)** 0 \({}^{\circ}\)C, **(II)** 4 \({}^{\circ}\)C, **(III)** 8 \({}^{\circ}\)C, and **(IV)** 12 \({}^{\circ}\)C. Untreated samples served as controls. _B. thermosphacta_, but this was counteracted by _\"tsipouro\"_, resulting in maximum population levels from 6.38 \(\pm\) 0.45 to 7.93 \(\pm\) 0.20 log CFU/g (Table 1). _B. thermosphacta_ dominated the microbial association of ground beef, while LAB were second in dominance, revealing a high growth potential at all assays (Figure 3). The dominance of those two, facultative anaerobic (_B. thermosphacta_) and microaerophilic (LAB), microorganisms is mainly associated with the type of MAP applied. Previous studies have reported _B. thermosphacta_ and/or LAB as the most prevalent in meat products such as pork steaks, beef patties, and beef steaks packaged under high oxygen MAP, namely 60-80% O\({}_{2}\): 40-20% CO\({}_{2}\)[15; 34; 35]. Yeasts-moulds had limited contribution to the spoilage association, profoundly due to their aerobic metabolism, which is not favoured by elevated CO\({}_{2}\) and/or O\({}_{2}\) levels compared to air (Figure 3I.d,IV.d). Specifically, they showed either 100% inhibition during storage at 0 \({}^{\circ}\)C or an average increase of _max_. 2.0 log CFU/g when samples were stored at temperatures higher than 4 \({}^{\circ}\)C, regardless of treatment. Although _Pseudomonas_ species are recognized as obligate aerobes with solely aerobic respiratory metabolism [36], a moderate growth rate was observed on controls reaching population of 6.0-7.0 log CFU/g at the end of storage above 4 \({}^{\circ}\)C where the recorded oxygen was close to 50% (Figures 2 and 3 II.b-IV.b). Similarly, [PERSON] et al., (2017) detected _Pseudomonas_ spp. in early, mid and very late spoilage stage on high oxygen MAP beef steaks stored at 10 \({}^{\circ}\)C even with up to 90% CO\({}_{2}\) and oxygen level down to 1% [34]. Moreover, it is also notable that when _\"tsipouro\"_ was applied on ground beef, standard deviations of the enumerated pseudomonads populations were significantly high in contrast to the respective on controls. From the antimicrobial treatment standpoint, which is the main objective of the present study, growth rates of _B.