Inhibitory effect of nisin and ascorbic acid on Alicyclobacillus acidoterrestris in orange juice

Subject Areas : Food Microbial Contamination

Fatemeh  Sabaghi ¹ (M.Sc. Student, Department of Food Science and Technology, Faculty of Agriculture, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran)
Rezvan  Pourahmad ² (Associate Professor, Department of Food Science and Technology, Faculty of Agriculture, Varamin-Pishva Branch, Islamic Azad University)
Mahnaz  Hashemiravan ³ (Assistant Professor, Department of Food Science and Technology, Faculty of Agriculture, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran)

Received: 2019-03-03 Accepted : 2019-06-11 Published : 2019-09-23

Keywords: Ascorbic acid, Nisin, Orange juice, Alicyclobacillus acidoterrestris,

Abstract :

Alicyclobacillus acidoterrestris (A. acidoterrestris) is a thermophilic spore-forming bacterium that changes taste and smell of juices. The aim of this study was to investigate the inhibitory effect of nisin and ascorbic acid on A. acidoterrestris. Nisin (150 and 200 ppm) and ascorbic acid (100 and 250 ppm) were used in orange juice contaminated with A. acidoterrestris. Microbial, physicochemical, and sensory properties of the samples were investigated during 90 days’ storage. Adding nisin and ascorbic acid significantly (P<0.05) decreased the number of A. acidoterrestris in orange juice. The sample containing 200 ppm nisin+250 ppm ascorbic acid and the sample containing 200 ppm nisin+100 ppm ascorbic acid had the lowest number of A. acidoterrestris, respectively. During storage, the number of bacteria in samples containing nisin and ascorbic acid decreased significantly (P<0.05) so that no bacterial growth was seen in the sample containing 200 ppm nisin and 250 ppm ascorbic acid on the 60th and 90th days and the sample containing 200 ppm nisin+100 ppm ascorbic acid on the 90th day. Acidity of the samples increased and brix decreased significantly (P<0.05) during storage. The sample containing 150 ppm nisin +100 ppm ascorbic acid and the sample containing 200 ppm nisin +100 ppm ascorbic acid had the highest score of overall acceptance. The sample containing 200 ppm nisin +100 ppm ascorbic acid was selected as the best sample with regard to microbial and sensory properties. Therefore, orange juice containing nisin and ascorbic acid has suitable sensory quality and can affect the inhibition of A. acidoterrestris.