Occurrence and Identification of Yeasts in Production of White-Brined Cheese

Abstract

The aim of this study was to reveal the sites of yeast contamination in dairy production and perform taxonomic characterization of potential yeast spoilers in cheese making. Occurrence of spoilage yeasts was followed throughout the manufacture of white-brined cheese at a Danish dairy, including the areas of milk pasteurization, curd processing, and packaging (26 sites in total). Spoilage yeasts were isolated from whey, old cheese curd, and air samples in viable counts of 1.48–6.27 log CFU/mL, 5.44 log CFU/g, and 1.02 log CFU/m3, respectively. Yeast isolates were genotypically classified using (GTG)5-PCR fingerprinting and identified by sequencing of the D1/D2 region of the 26S rRNA gene. The largest yeast heterogeneity was found in old curd collected under the turning machine of molds, where 11 different yeast species were identified. The most frequently isolated yeast species were Candida intermedia, Kluyveromyces marxianus, and Pichia kudriavzevii. The less abundant yeast species included Candida auris, Candida parapsilosis, Candida pseudoglaebosa, Candida sojae, Cutaneotrichosporon curvatus, Cutaneotrichosporon moniliiforme, Papiliotrema flavescens, Rhodotorula mucilaginosa, Vanrija humicola, and Wickerhamiella sorbophila. The awareness on occurrence and taxonomy of spoilage yeasts in cheese production will contribute to a knowledge-based control of contaminating yeasts and quality management of cheese at the dairies.

Regulation of lactose and galactose growth: Insights from a unique metabolic gene cluster inCandida intermedia

“…Our results show that C. intermedia grows relatively fast on lactose, and strains of this species have been isolated several times from lactose-rich niches including fermentation products like white-brined cheese 46 and cheese whey 47 . In these lactose-rich environments, survival likely necessitates a genetic makeup that can help outcompete rivaling microorganisms.…”

Microbiological aspects of the traditional Travnik/Vlašić cheese manufactured in Bosnia and Herzegovina

“…The appearance of yeasts in some acidified dairy products in high numbers may be caused by their ability to grow in low water activities (aw) and low temperatures, and ability to tolerate low pH and high salt concentrations [13]. The presence of yeasts can lead to various quality defects, especially when grown in high numbers 5-6 log CFU/g, and this can result in softening of the cheese texture, discoloration, off-flavours, and swelling of the cans [14]. The mean and minimum counts for yeasts and moulds, obtained in our study, were slightly higher than those for artisanal Turkish White Pickled cheese [15], while the maximum count was similar.…”

Characterization of Yeast Isolated from Berkeep, a Traditional Fermented Milk Products of Darfur State, Western Sudan

“…Kluyveromyces marxianus, Saccharomyces cerevisiae and Candida intermedia were among the yeast isolated from Serro Minas, a traditional Brazilian cheese by Cardoso et al (2015). Abdelgadir et al (2001) 2012) isolated 36 different species, with the most prominent being Candida lusitania, Cryptococcus laurentii, S. cerevisiae).Candida intermedia, Kluyveromyces marxianus, and Pichia kudriavzevii were the most frequently isolated yeast species in white-brined cheese and have been characterized as typical dairy spoilers at the Danish Dairy (Geronikou et al, 2022).In Chal, a fermented camel milk of Golestan province of Iran, Yam et al (2015) reported Kluyveromyces lactis and K. marxianus as being the dominant yeast. This species difference with in the various fermented milk products probably due to differences in raw material, environmental factors (temperature, humidity etc.)…”