The Influence of pH, NaCl, and the Deacidifying Yeasts Debaryomyces hansenii and Kluyveromyces marxianus on the Production of Pigments by the Cheese-Ripening Bacteria Arthrobacter arilaitensis

Abstract

Arthrobacter arilaitensis is a food-related bacterial species under investigation for its involvement in the coloration of surface-ripened cheeses. Presently, information about this species in association with the development of appropriate cheese coloration is still lacking. This study was performed in order to investigate—with the use of spectrocolorimetry—the influence of pH, NaCl, and deacidifying yeasts on the pigmentation of Arthrobacter arilaitensis biofilms. Three types of cheese-based (curd) solid media were prepared by using different deacidification methods: (i) chemical deacidification by NaOH (CMNaOH); (ii) biological deacidification by the yeast strain Debaryomyces hansenii 304 (CMDh304); and (iii) biological deacidification by the yeast strain Kluyveromyces marxianus 44 (CMKm44). Each medium was prepared with initial pH values of 5.8, 7.0, and 7.5. After pasteurization, agar was incorporated and NaCl was added in varying concentrations (0%, 2%, 4%, and 8% (w/v)). A. arilaitensis Po102 was then inoculated on the so prepared “solid-curd” media, and incubated at 12 °C under light conditions for 28 days. According to the data obtained by spectrocolorimetry in the Compagnie Internationale de l’Eclairage (CIE) L*a*b* color system, all controlled factors appeared to affect the pigments produced by the A. arilaitensis strain. NaCl content in the media showed distinct inhibitory effects on the development of color by this strain when the initial pH was at 5.8. By contrast, when the initial pH of the media was higher (7.0, 7.5), only the highest concentration of NaCl (8%) had this effect, while the coloring capacity of this bacterial species was always higher when D. hansenii 304 was used for deacidification compared to K. marxianus 44.

Evaluating the Authenticity of the Raw-Milk Cheese Fontina (PDO) with Respect to Similar Cheeses

“…Fontina PDO is characterized by a reddish sticky surface, naturally formed by the microflora of the surrounding environment which colonizes the rind during the ripening period [ 3 ]. A minor diversity of coloration of smear cheese rind may depend on the interactions between microbial species, pH, NaCl concentration, and temperature [ 16 , 17 ]. By contrast, the rind of Fontal cheese is usually coated with a protective film (paraffin, wax, or varnish) to prevent the growth of surface microflora and colored with red-brown pigments to obtain a standardized external appearance of the cheese regardless maturity.…”

Identification of Red Pigments Produced by Cheese-Ripening Bacterial Strains of Glutamicibacter arilaitensis Using HPLC

“…Besides the yellow pigments, which were characterized as a group of C50 carotenoids consisting of eight forms, but mainly decaprenoxanthin, G. arilaitensis has recently been reported to synthesize red pigment(s) [17][18][19]. In our previous study [19], a strain of G. arilaitensis, Po102, evidently developed pink/red-brown color suffusing inside inoculated cheese-based (curd) solid media. After a tentative determination, the results showed that the pink pigments excreted by this strain were water-soluble and fluoresced under UV light.…”

“…Arthrobacter arilaitensis (presently named Glutamicibacter arilaitensis-to be up to date, G. arilaitensis will be used throughout this article) is one of the important bacterial strains responsible for the pigmentation of cheese rinds due to its presence at different stages of the ripening process, principally at the middle and late stages [15,16]. Besides the yellow pigments, which were characterized as a group of C50 carotenoids consisting of eight forms, but mainly decaprenoxanthin, G. arilaitensis has recently been reported to synthesize red pigment(s) [17][18][19]. In our previous study [19], a strain of G. arilaitensis, Po102, evidently developed pink/red-brown color suffusing inside inoculated cheese-based (curd) solid media.…”

“Cheese: Technology, Compositional, Physical and Biofunctional Properties:” A Special Issue

“…The color of the rind of smear-ripened cheeses is the objective of the research paper by Sutthiwong et al [8]. They report that the yellow colonies of Arthrobacter arilaitensis (now Glutamicibacter arilaitensis ) greatly contribute to the pigmentation of this type of rind.…”