bɹˈɑːməθˌɪmɑːl blˈuː ɪz ðɪ ˈɪndᵻkˌeɪɾɚ jˈuːzd ɪnðɪ ˈeɪɡɑːɹ, ɪt tʃˈeɪndʒᵻz tə jˈɛloʊ ɪn kˈeɪs ʌv ˈæsɪd pɹədˈʌkʃən dˈʊɹɹɪŋ fɜːməntˈeɪʃən ʌv lˈæktoʊs ɔːɹ tʃˈeɪndʒᵻz tə dˈiːp blˈuː ɪn kˈeɪs ʌv ˌælkəlˌaɪnᵻzˈeɪʃən.
Bromothymol blue is the indicator used in the agar, it changes to yellow in case of acid production during fermentation of lactose or changes to deep blue in case of alkalinization.