Characterisation of changes in physicochemical, textural and microbiological properties of Njeguska sausage during ripening.

ABSTRACT

The purpose of this paper was to investigate effect of ripening time on physicochemical, textural and microbiological properties of Njeguska (dry fermented sausage) during ripening and to conduct sensory and free fatty acid characterization of final product. Ripening time significantly (p < 0.05) affected all physicochemical parameters. Moisture content dropped below national regulation limit (35%) after 12 days, which indicates that production process could be shortened for 4 days. Total weight loss was 36.34%. Due to its final pH (5.54), Njeguska can be classified as low-acid sausage which microbial safety mostly relies on its low water activity (< 0.80). Final TBARS value was 0.27 mg MDA/kg. Levels of tyramine (36.9 mg/kg) and putrescine (16.7 mg/kg) were the highest among all biogenic amines while levels of remaining amines were under 5 mg/kg. Hardness, gumminess and chewiness significantly (p < 0.05) increased during processing to reach final values of 65.59 N, 33.60 N and 19.12 N, respectively. Ripening time had significant effect on color (L*, a* and b*) of surface, meat and fat parts which were all measured separately. Total viable count, lactic acid bacteria and Micrococcaceae counts increased from 5.11 log cfu/g, 3.90 log cfu/g and 2.41 log cfu/g to 7.96 log cfu/g, 7.04 log cfu/g and 4.86 log cfu/g, respectively. Results of sensory characterization showed high scores for smoky flavor, consistency, fattiness, fat/meat cohesiveness and saltiness while lactic acid odor and overall acidity were rated low.