## 5 Use of _Apium_ Plants in Food Preservation
Indeed, [PERSON] and [PERSON] demonstrated that the celery juice or powder and starter culture treatment is an efficient alternative instead of direct addition of sodium nitrite into frankfurter-style cured hams and sausage [136]. The improvement of safety of \"naturally cured (no-nitrite-or-nitrate-added)\" meats implies a cured cooked meat model system consisting of several natural ingredients (2% salt, 10% water, 80:20 pork, and 150 or 50 ppm ingoing sodium nitrite) that closely looks like the commercial frankfurters that reduced _Listeria monocytogenes_ inhibition (\(p<0.05\)) in the major part of the uncured meat products (nitrite or nitrate free, with celery powder as the nitrate source) as compared with control samples conventionally produced with direct addition of sodium nitrite [137]. Sodium nitrite is included in the production of cured meat products to provide the characteristic color, flavor, and microbiological safety [138]. Studies have linked the consumption of processed meats containing nitrites to the risk of certain types of cancer [139; 140]. In the last decades, the increased demand for nitrite or nitrate-free meat products led many manufacturers to use celery powder, containing a substantial amount of nitrate (celery can contain as high as 1500 ppm to 2800 ppm nitrate or greater than 2500 mg nitrate/kg) in combination with a starter culture to reduce nitrate to nitrite during this process [136; 137; 141; 142]. _Apium petroselinum_ essential oil demonstrated antibacterial effects on food spoilage bacteria, _A. faecalis_ and _S. dysenteriae_ bacteria [142]. Previous studies have also reported that the essential oils and extracts of the _Apium petroselinum_ and _A. graveolens_ are effective on various bacteria such as _S. dysenteriae_, _E. coli_, and _S. aureus_[143]. Their results suggest that the replacement of synthetic preservatives with the essential oils of these natural healthy compounds can be applied as an alternative way to increase the shelf-life of several special foods [142]. However, to prove its usefulness as a food preservative, the antimicrobial activity of _A. graveolens_ essential oil, of known composition, needs to be assessed in specific food products. The effective antimicrobial dose of oil may exceed the sufficient level for flavoring purposes because of its unique taste and aroma [141]. Thus, the use of _Apium_ plant oil would probably be limited in food products. [PERSON] et al. indicated that the essential oil of _Apium nodiforum_ (L) Lag, which is used as a culinary herb,showed antimicrobial activity against _Helicobacter pylori_ with a minimum inhibitory concentration (MIC) of 12.5 ug/mL [144]. _Pseudomonas putida_ is one of the most important spoilage bacteria in meat and meat products. [PERSON] et al. investigated the effect of several essential oils against _P. putida_ to see their antibacterial activity. [PERSON] et al. showed that oils which already had proven antimicrobial properties appeared to have little or no effect against the _P. putida_ strain. However, the _Apium_ plant showed antimicrobial activity at a MIC of 0.8% wt/vol. against _P. putida_[131]. Thus, celery powder and juice are highly compatible sources of nitrite for process meat products due to their mild flavor profile and fairly low vegetable pigment that does not impart the final product flavor [136; 141; 145]. Indeed, the use of celery juice or powder in processed meat products is widely known [113; 119; 133; 119]. In addition to this, the growth of pathogenic microorganisms including _Listeria monocytogenes_, _Clostridium botulinum_, and _Clostridium perfringens_ in processed meats containing celery juice or celery powder has been investigated. Celery juice treatments at both 100 and 200 mg/kg resulted in growth of _L. monocytogenes_ similar to that of conventional nitrite at the same concentrations used in ham [145]. The researchers indicated that celery juice may increase the meat product pH which could have an impact on antimicrobial properties of nitrite in some products. The control of _L.