Lactobacillus acidophilus is one of the most commonly used probiotics. This study aimed to produce low salt (3% Nacl) soft cheese with acceptable organoleptic characters and prolonged shelf-life using Lb.acidophilus (1 and 3%) as bio preservative. The obtained cheese (control, 1%Lb. and 3%Lb.) were kept in refrigerator, sampled fresh (zero time) and at 3days intervals till signs of spoilage were detected. Samples were examined organoleptically, chemically and microbiologically. Results showed that 3% Lb. cheese was superior to 1%Lb. and control cheese when fresh with an average organoleptic overall score of 95.96, 94.04 and 90.82, respectively. pH values at zero time for control, 1% Lb. and 3% Lb. cheese were 6.42, 6.33 and 6.17 then decreased at the end of shelf life (at 15th, 18th and 24th day)to 5.89, 5.65 and 5.43, respectively. Average coliforms count (MPN/g) was 3.6x101, 1.1x101 and 0.93x101 at zero time then reached 7.5x104, 0.93x101 and 2.3x101 at the end of shelf life for control, 1% Lb. and 3% Lb. cheese, respectively. While, E.coli was absent from all examined low salt soft cheese throughout the entire period. On storage, Lb.acidophilus was -sharply increased in their numbers-1.34x108 and 2.18x109 cfu/g for 1% Lb. (at the 18th day) and 3% Lb. cheese (at the 24th day). Effect of Lb. acidophilus strain on mould and yeast count were highly significant (P<0.01). In conclusion, low salt soft cheese with 3% Lb.acidophilus culture had better organoleptic score, microbiological quality and prolonged shelf-life than control and 1% Lb cheese. |
