Effect of Propionibacterium shermanii metabolites on sensory properties and shelf life of UF‐Feta cheese

Abstract

Purpose

Fungal growth on UF‐Feta cheese is one of the most important factors of consumer dissatisfaction in Iran. Propionibacterium shermanii metabolites was used as a biopreservative to retard this inconvenient. This research was done to determine the concentration of the metabolite that increases cheese shelf life with no adverse effect on sensory properties.

Design/methodology/approach

The cheese was manufactured according to the methods used in the Iranian UF‐Feta cheese dairy plants. The metabolite was used in the order of 0.5 and 1 per cent (w/w) of retentate weight. After incubation while reaching the required pH, cheese samples were stored at two temperatures including 4 and 25 degree C in which analysis was done during a period of 90 and 70 days respectively. Effect of the metabolite on shelf life (absence of visible fungi growth), total viable fungi, microbial load, pH as well as sensory properties including taste, odour, colour and overall acceptability was compared with the control (untreated sample).

Findings

Results showed that the shelf life duration of the cheese was extended by approx. 35–43 per cent. Total viable fungi was most efficiently reduced using the metabolite but there was no significant differences in microbial load. Addition of the metabolite didn’t affect pH of cheese at either temperatures compared with control. Results of sensory evaluation showed that the taste and odour of cheese containing 0.5 per cent of the metabolite was preferred as compare to the others (p<0.1). The intervension had no effect no effect on colour scores of cheese. The texture of control was better than the others (p<0.1).

Originality/value

In UF‐Feta cheese, the presence of fungi represents a major concern for cheese manufacturers. The results indicate that the fungal growth can be minimized using Propionibacterium shermanii metabolites without undesirable effects on sensory properties. The potential of the metabolite to inhibit yeast growth on UF‐Feta cheese was a new finding in this research.

Citation

Mohamadi Sani, A., Ehsani, M.R. and Mazaheri Asadi, M. (2005), "Effect of Propionibacterium shermanii metabolites on sensory properties and shelf life of UF‐Feta cheese", Nutrition & Food Science, Vol. 35 No. 2, pp. 88-94. https://doi.org/10.1108/00346650510585877