Application of pulsed UV light for inactivation of Saccharomyces cerevisiae yeast

Danas je u svijetu sve veća potreba za produljenjem roka zdravstvene ispravnosti prehrambenih proizvoda uz primjenu što brže i jednostavnije tehnologije i što manjeg utjecaja na nutritivni sastav zapakiranog proizvoda. Zato se sve više počinju istraživati netoplinske tehnike obrade proizvoda poput tretmana pulsirajućim UV svjetlom kod kojeg ne dolazi do značajnog razvoja topline tijekom tretmana uz pritom vrlo dobru inaktivaciju mikroorganizama. Zato je cilj ovog rada bio dokazati uspješnost tretmana pulsirajućim UV svjetlom za inaktivaciju kvasca Saccharomyces cerevisiae u dvije različite ambalaže uz promjenjive parametre vremena trajanja tretmana i udaljenosti uzorka od izvora zračenja. Rezultati istraživanja pokazali su najveću uspješnost u inaktivaciji kvasca nakon tretmana u ambalaži PP/Ac/PVDC koja je karakteristična po svojoj propusnosti za elektromagnetsko zračenje te je dobivena 100%-tna decimalna redukcija kvasca. Kod tretmana u ambalaži PPmet/PE, koju karakterizira neprozirnost i time nepropusnost na elektromagnetsko zračenje, nije bilo decimalne redukcije kvasca te se kao takva pokazala neprimjerenom za tretman pulsirajućim UV svjetlom.Today, there is a growing need to extend the shelf life of food products with the application of the faster and simpler technology with the minimum impact on the nutritional composition of the packaged product. Therefore, non-thermal techniques of product processing, such as treatment with pulsed UV light, in which there is no significant development of heat during the treatment with very good inactivation of microorganisms, are increasingly being researched. The aim of this study was to prove the success of treatment with pulsed UV light in inactivation of the yeast Saccharomyces cerevisiae in two different packages with variable parameters of treatment being duration and distance of the sample from the radiation source. The results of the research showed the greatest success in yeast inactivation after treatment in PP/Ac/PVDC packaging, which is characterized by its permeability to electromagnetic radiation, and a 100% decimal reduction of yeast was obtained. In the treatment in PPmet/PE packaging, which is characterized by opacity and thus impermeability to electromagnetic radiation, there was no decimal reduction of yeast and as such is unsuitable for treatment with pulsed UV light