Abstrak
<p>This research study about use of prebiotic <em>Ipomea batatas</em> L. and probiotic <em>Lactobacillus casei</em> at milk fermentation. The usage of simbiotic increase, recentely, especially, for husbandarys products, such as milk fermentation the purpose of this study was to find out the best composition of prebiotic <em>Ipomoea batatas</em> L and probiotic <em>Lactobacillus casei</em> given in the process of simbiotic milk fermentation. The method used for this experiment was random cluster, factorial 4 x 3 with 3 times of re-treatment, and was analyzed with BNT and BNJ testing. “A” factor was the use of prebiotic <em>Ipomoea batatas</em> L. (0%, 7,5 %, 15 %, 22,5 %), and “B” factor was the use of probiotic <em>Lactobacillus casei</em> (2%, 3%, 4 %) the component measure were BAL , water and TTA the result of this study was shown that the best use of prebiotic <em>Ipomoea batatas</em> L and probiotic <em>Lactobacillus casei</em> in the process of symbiotic milk fermentation were in the composition of highest BAL : 21,40 x 10<sup>8</sup> cfu/ml. the highest TTA and water were 0,21 % and 71,98 22,5 % of prebiotic <em>Ipomoea batatas</em> L. and 4% probiotic Lactobacillus casei consentrate.</p><p> </p><span>Key words:</span><strong> </strong><span>prebiotic, </span><em>Ipomea batatas</em><span> L., probiotic, </span><em>Lactobacillus casei</em><span>, milk fermentatio</span>