Resistance of Paecilomyces variotii Mold Ascospores to Dense CO₂ and Dense CO₂- Assisted Thermal Processing

Abstract:

Paecilomyces variotii is one of the heat-resistant fungi that causes spoilage problems, especially in processed fruit products. Many non-thermal methods have been tested for their efficacy to inactivate spoilage and pathogenic microorganisms. The objectives of this study were to use dense CO₂ (HPCD) and their combination with thermal processing at 50-90oC to reduce the population of P. variotii mold ascospores in orange juice. Application of dense CO₂ between 0.4 to 0.8 MPa for 30 min only reduced <1.0 log of these spores. The highest log reductions achieved (2.24 log) were shown by sequential treatments of 0.8 Mpa pressurized CO₂ for 30 min followed by 90oC-30 min thermal processes. Soluble solid content (10-30oBrix) affected the spore reduction by dense CO₂-assisted thermal processing, being higher at lower oBrix. These results indicate that P. variotii mold ascospores were highly resistant to these treatments. Increasing the pressure of HPCD treatment might improve the log reductions required for food pasteurization.

• Periodical: Advances in Science and Technology (Volume 138)
• Pages: 27-32
• DOI: https://doi.org/10.4028/p-pZ1d7o
• Online since: January 2024
• Authors: Evelyn Evelyn*, Chairul Chairul, Lamboi Lamboi, Arie Choyungsya
• Keywords: Dense CO₂, Dense CO₂- Assisted Thermal, Fruit Juice, Mold Ascospores, Soluble Solid

References

[1] B. Steiner, V.R. Aquino, A.A. Paz, L.M. da Rocha Silla, A. Zavascki, L.Z. Goldani, Paecilomyces variotii as an emergent pathogenic agent of pneumonia, Case Rep. Infect. Dis. 273848 (2013) 1-3.

DOI: 10.1155/2013/273848

[2] E. Pieckova, R.A. Samson, Heat resistance of Paecilomyces variotii in sauce and juice, J. Ind. Microbiol. Biotechnol. 24 (2000) 227-230.

DOI: 10.1038/sj.jim.2900794

[3] T. Swami, S. Pannu, M. Kumar, G. Gupta, Chronic invasive fungal rhinosinusitis by Paecilomyces variotii: a rare case report, Indian J. Med. Microbiol. 34 (2016) 103-106.

DOI: 10.4103/0255-0857.174126

[4] R.A. Samson, E.S. Hoekstra, J.C. Frisvad, O. Filtenborg, Introduction to Food-Borne Fungi, fifth edn., Centraalbureau Voor Schimmelcultures, Baarn-Delft, 1996.

DOI: 10.1007/s11046-005-4201-1

[5] J. Houbraken, R.A. Samson, J.C. Frisvad, Byssochlamys: significance of heat resistance and mycotoxin production, in: A.D. Hocking, J.I. Pitt, R.A. Samson, U. Thrane (Eds.), Advances in Experimental Medicine and Biology, Springer, Boston, MA, 2006, pp.211-224.

DOI: 10.1007/0-387-28391-9_14

[6] Evelyn, F.V.M. Silva, Heat assisted HPP for the inactivation of bacteria, moulds and yeasts spores in foods: log reductions and mathematical models, Trends Food Sci. Technol. 88 (2019) 143-156.

DOI: 10.1016/j.tifs.2019.03.016

[7] Evelyn, F.V.M. Silva, Ultrasound assisted thermal inactivation of spores in foods: pathogenic and spoilage bacteria, molds and yeasts, Trends Food Sci. Technol. 105 (2020) 402-415.

DOI: 10.1016/j.tifs.2020.09.020

[8] T. Yu, L. Niu, H. Iwahashi, High-pressure carbon dioxide used for pasteurization in food industry, Food Eng. Rev. 12 (2020) 364-380.

DOI: 10.1007/s12393-020-09240-1

[9] P. Ballestra, J.L. Cu, Influence of pressurized carbon dioxide on the thermal inactivation of bacterial and fungal spores, Lebensm.-Wiss. u.-Technol. 31 (1998) 84-88.

DOI: 10.1006/fstl.1997.0299

[10] L. Rao, X. Bi, F. Zhao, J. Wu, X. Hu, X. Liao, Effect of high-pressure CO2 processing on bacterial spores, Crit. Rev. Food Sci. Nutr. 56 (2016) 1808-1825.

DOI: 10.1080/10408398.2013.787385

[11] Evelyn, Chairul, S. Sriningsih, and Y. Aulia: submitted to International Conference on Food Science and Engineering or ICFSE (2022).