[Optimisation des conditions de production du hallou demi-ecreme]

The aim of the study was to develop the optimal conditions for the manufacturing of low-fat halloum cheese without significant alterations of the organoleptic attributes. Twenty one experiments were carried out on a factorial design basis to study the effect of various factors on the quality of finished halloum. These include the level of fat [0.05-1.4% in the milk], lecithin [0.04-0.1%], CaCl[2] [0.01-0.02%], temperature [30 +/- 2[degree sign]C], time of coagulation [45-60 min], and pH [6.61-6.78]. For each experiment, samples of milk and resultant cheese were subjected to analysis of moisture, fat-in-dry matter, pH and acidity. The texture of cheese was determined using a penetrometer. Sensory properties of the finished halloum were carried out to evaluate saltiness, bitterness, insipidness, aftertaste, chewiness, sourness and overall acceptance using the profiling method. Physicochemical characteristics and sensory properties demonstrated significant correlations between attributes. The texture is influenced by dry matter of milk [R=0.73, P<0.01] and duration of cooking [R=0.56, P<0.05]. Overall acceptance was significantly correlated to fat [R=0.54, P<0.05], white color [R=0.64, P<0.01], hardness [R=0.61, P<0.01] and chewiness [R=0.48, P<0.05]; and negatively correlated to bitterness [R=-0.67, P<0.01] and aftertaste [R=-0.72, P<0.01]. The optimal conditions to have a low fat halloum was to use a low fat milk [<0.85%], a low coagulation temperature [28 [degree sign] C], a prolonged time of coagulation [60 min] and reduced time of cooking [5-8 min]

[Chemical and microbiological characteristics of Lebanese cheeses of local industeries]

In order to characterize, protect dairy products and develop new probiotics, a survey was conducted amongst 37 dairy factories. Chemical [pH, acidity, DM, protein, fat, soluble nitrogen and free fatty acid] and microbiological [total aerobic bacteria, Coliforms, E. coli, Salmonella, Listeria, and Staphylococcus aureus] analysis were carried out on samples collected from factories [7 Baladi, 22 Akkawi, 18 Double creme and 22 Halloum] of different regions. These cheeses are made by 73% of visited factories. Chemical analysis showed low acidity [0.18 to 0.26%], variable levels of moisture [54 to 70%] protein [19 to 24%] and fat [12 to 18%] except Double crŠme [3.26 +/- 1.78%]. Except 8%, Good Hygienic and Manufacturing Practices [GHP/GMP] are not applied in visited factories. This is confirmed with the high levels of Coliforms, detectable in most varieties at an alarming level [72 a 86%]. Besides, 23-71% of samples were contaminated with E. coli. However, all samples were found free of staphylococcus aureus; Halloum cheese was the only one free of Listeria and Salmonella. The highest off standard for these bacteria was noticed in Baladi cheese where 29% were contaminated with Listeria and Salmonella. Listeria was also found in 10% of Akkawi and 17% of Double crŠme. These results show a violation of the Good Hygienic and Manufacturing Practices [GHP/GMP] by most factories in all visited regions