GROWTH-CHARACTERISTICS OF ACIDURIC SPOREFORMING BACILLI ISOLATED FROMFRUIT JUICES

Two aciduric, aerobic, sporeforming bacteria were isolated from pasteu rized juices. The gram-positive, catalase-positive rods produced spore s that were located subterminally in a swollen sporangium. The culture s had an optimal pH of 3.5-4.0 for growth and preferred potato dextros e agar over many of the rich media usually used for cultivating sporef orming bacteria. Spore inocula grew well in apple juice and white grap e juice. Red grape juice was inhibitory, perhaps because of the concen trations of certain phenolic compounds. The spores were sufficiently h eat resistant (D-90 values of 16 to 23 min and z-values of 7.2 to 7.7 degrees C) to survive commercial pasteurization processes.