The role of olive oil in the preservation of yogurt cheese (labneh anbaris)

Small 'balls' of yogurt cheese (40 g 100 g(-1) total solids), derived by ex tracting moisture from concentrated yogurt (23% total solids), can be store d in retail outlets in the Il the Middle East (20-25 degrees C) under virgi n olive oil for trp to two years. The absence of over-acidification appears to be due to the inhibitory effect of low pH (3.8), low available water (0 .85) and salt (1.0 g 100 g(-1)) on starter activity, while the anaerobic co nditions created bq, the oil both reinforce these inhibitory factors and ad ditionally, prevent the growth of yeasts over the surface of the individual balls. The type of vegetable oil covering the balls was found to be unimpo rtant, and sunflower, safflower and cottonseed oil were equally effective i n preserving yogurt cheese inoculated with Kluyveromyces marxianus subsp ma rxianus and stored for three months at 25 degrees C.