## 4 Discussion
While pomace extracts may contain a variety of bioactive compounds, the lack of synergy or the presence of certain compounds, such as sugars or enzymes, may reduce their antimicrobial effectiveness [69; 70]. It is evident that organic acids have a substantial impact on the pH of the medium, resulting in the creation of an environment that is conducive to the inhibition of bacterial growth. It is noteworthy that pomace extracts may not adequately acidify the environment unless they are concentrated or supplemented. In the case of Golden Delicious apple pomace extract, successful antimicrobial and antioxidant activity was found [71]. It was concluded that the antioxidant activity was provided by compounds belonging to the flavonoid group of apple pomace. The pomace extract showed good inhibitory activity against _Staphylococcus aureus_ and _Escherichia coli_. Phloridzin and phloretin have the potential to be used as natural alternatives to synthetic antioxidants and antimicrobial agents. Also, in the case of apple pomace, a high percentage of inhibition was shown against _S. enterica_, _S. aureus_, and _E. coli_, and a high correlation was shown between the total phenolic content and the percentage of bacterial inhibition of pomace extracts [72]. Similar results were reported for chokeberry pomace extract against food-borne strains of _S. aureus_, _E. coli_, and _Streptococcus pyogenes_. Furthermore, both aqueous and ethanolic extracts were highly effective against pathogens even at low (5%) concentrations [73]. In the case of analytical measurements, a comparative analysis of the treated samples and the corresponding control samples was conducted. The sweet potato cubes were subjected to a surface colour measurement, refraction (water-soluble dry matter content), and a pH measurement. Subsequently, extracts were prepared from the ground samples, enabling the total polyphenol content and antioxidant capacity to be quantified. The findings of this study demonstrate that the antimicrobial properties of fruit pomace are less pronounced than those exhibited by organic acids. However, it would be advantageous to investigate the potential of utilising fruit pomace in conjunction with acids. This approach has the potential to enhance the efficacy of the utilisation of pomace in food production. The combination of organic acids with fruit pomace extracts may result in a synergistic antimicrobial effect, whereby the combined impact of the mixture may exceed the sum of the individual components' actions. The combination can attack microbes through multiple mechanisms, making it harder for them to adapt or resist. The employment of both agents may facilitate reduced concentrations of each microbe, thereby minimising the potential for adverse sensory or toxic effects, a matter of particular significance in the context of food applications. Furthermore, beyond its role in preservation, pomace provides fibre, antioxidants, and phytochemicals, thereby enhancing the nutritional value of food or supplements. The combination of natural by-products, such as pomace, with organic acids is in alignment with consumer demand for natural, clean-label food preservatives. Moreover, it adds value to agricultural waste, thus contributing to the principles of a circular economy.