A study towards the improvement of Jameed quality and solubility

Jameed is a fermented dairy product in the form of stone hard balls or other shapes produced by straining the heated buttermilk on cloth mesh bags, salting the formed paste by kneading, shaping and drying in the sun. This product is reconstituted after the integration to be used in the preparation of Mansaf, the national dish in Jordan, which is basically lamb meat cooked in Jameed sauce (Sharab, Mareece) and served on cooked rice. The reconstitution of Jameed is a tedious work since the product is difficult to break and to disperse, and the dispersion often lacks stability. This study aimed mainly at improving the solubility of Jameed and the colloidal stability of its dispersion. For this purpose wettability and a syneresis test of dispersion were developed for the measurement of Jameed solubility. A natural convection solar dryer was designed for drying Jameed balls formed from the strained buttermilk (Jameed paste). The dryer proved to be suitable and protected Jameed from discoloration, cracks and contamination. Three directions were investigated to improve the disperse ability of Jameed: treating buttermilk with different pasteurization temperature, the use of additives and applying different dehydration methods. Treating buttermilk at 55 degree C for 3 min had the best result regarding Jameed paste yield and solubility, along with the enhancement of Jameed paste texture compared with other heat treatments. The addition of gum arabic (0.5%), starch (1%), and carrageenan (0.15%) to the Jameed paste resulted in improvement of solar dried Jameed with significant result for carrageenan treatment as evaluated by wettability, and syneresis test. Whipping of paste to which carrageenan was used, added an additional improvement to the solubility of Jameed and stability of its dispersion. The addition of baking powder (2%) to the Jameed paste to produce a porous dried product gave an inferior Jameed as indicated by the solubility test and compared to control. Microwave drying was the worst regarding the effect on solubility of the product, whereas freeze-drying was the best; the other drying methods could be ordered as follows: microwave drying, rotating plate dryer, oven drying, solar drying and freeze-drying. The sensory evaluation of the souce prepared from the best two treatments produced from sheep milk using hedonic scale test, had higher mean scores than control market sample which was Karaki Jameed considered as the best quality in Jordan, without any significant difference between them