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 and sampled fresh (zero time) and at 3days intervals till sings of spoilage were detected (after 15, 18 and 24 days, respectively). Samples were examined organoleptically, chemically and microbiologically and result 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. The pH values at zero time for control, 1% Lb. and 3% Lb. cheese were 6.42, 6.33 and 6.17 and decreased at the end of shelf life to 5.89, 5.65 and 5.43, respectively. Microbiologically, average coliforms count (MPN/g) was 3.6 x101, 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 and reached 1.34x108 cfu/g for 1% Lb. cheese at the 18th day and 2.18x109 cfu/g for 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. |
