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Advances in Bioscience and Biotechnology, 2010, 1, 224-231 ABB doi:10.4236/abb.2010.13031 Published Online August 2010 (http://www.SciRP.org/journal/abb/) Development of acidophilus milk via selected probiotics & prebiotics using artificial neural network Zeynab Raftani Amiri1*, Pratima Khandelwal2, B. R. Aruna2 1Department of Food Science and Technology, Sari Agricultural Sciences and Natural Resources University, Sari, Iran; 2P.G. Department of Biotechnology, Brindavan College, Bangalore, India. Email: irajarash@rediffmail.com Received 27 April 2010; revised 30 May 2010; accepted 7 June 2010. ABSTRACT Published Online August 2010 in SciRes. http://www.scirp.org/journal/abb Commercial interest in functional foods containing probiotic strains has consistently increased due to the awareness of gut health. Recent advancements are leading to development of synbiotic foods, containing prebiotics and probiotics bearing synergistic effects of the two. Thus, in present study, synbiotic acido- philus milk was developed satisfying functional dairy food properties. Different sets of milk were fermented with probiotic cultures (Lactobacillus acidophilus, Bifidobacterium bifidum, Lactobacillus casei, bioyo-ghurt culture) singly or in combination, and prebiot-ics namely inulin (I), oat fibre (O) and honey (H). Obtained 20 synbiotic samples were organoleptically tested, physico-chemically (titrable acidity percent-age (TA) & pH) and microbiologically (total viable count (TVC), coliform count and yeast & mold count) analyzed. The incorporation of honey and inulin led to development of sweetened and low calorie sweet-ened synbiotic acidophilus milk, respectively. Incor-poration of B. bifidum increased the flavour of syn-biotic acidophilus milk when compared to L. aci-dophilus as control, where as L. casei culture showed thinner consistency in the product. Addition of pre-biotic affected only the sensory scores, whereas the probiotics addition resulted in a marginal variation of pH and TA. TVC of all synbiotic acidophilus milk samples obtained were more than desirable limits for harvesting probiotic effects (>10^10 cfu/ml). Finally, a two layer feed-forward artificial neural network (ANN) was established to predict the sensory evalua-tion based on inputs of probiotic and prebiotic. Keywords: Synbiotic Acidophilus Milk; Artificial Neural Network; Sensory Evaluation 1. INTRODUCTION Notable fermented milks are buttermilk, acidophilus milk, bulgarian buttermilk, kumiss, kefir and yoghurt. Acidophilus milk is a sour product that has been allowed to ferment under conditions that favor the growth and development of thermophilic lactic acid bacteria. This type of fermented milk is produced by development in milk of Lacatobacillus acidophilus. It is claimed that acidophilus milk has therapeutic and health-promoting properties. It is also claimed that the growth of Lacato-bacillus acidophilus under the condition existing in the intestinal tract can replace undesirable putrefactive er-mentation with a beneficial lactic fermentation [1]. Probiotics are technically defined as live microbial food ingredients that have a beneficial effect on human health. Some of the important beneficial effects are an-timicrobial activity, immune system modulation, an-timutagenic activity, colonization resistance activity, maintenance of micro-ecology of bowel, stimulation of Bifidobacteria, deactivation of carcinogens etc. Com- mercially available probiotic strains belong to genera Lactobacilli, Bifidobacterium, Streptococcus, Bacillus, Bacteriodes, Pediococcus, Leuconostoc, Propionibac-teruim [2-4], Saccharomyces cerevisia and Aspergillus oryzae [5]. The other key component of functional dairy or other products is prebiotic ingredient. Prebiotics are non- digestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria in colon that can improve the host health [6]. When prebiotics are used in combination with probi-otics or live bacteria, the resultant has synergistic effects, referred to as “synbiotic”. This is because in addition to the action of probiotics that promote the growth of ex-isting strains of beneficial bacteria in the colon, prebiot-ics such as inulin and oligofructose also act to improve the survival, implantation and growth of newly added probiotics strains. Inulin is a mixture of polymers consisting mainly of fructose unit; its partial enzymatic hydrolysis yields oli-gofructose. These are classified as prebiotic (dietary)