Pressure inactivation of yeasts, molds, and pectinesterase in satsuma mandarin juice: Effects of juice concentration, pH, and organic acids, and comparison with heat sanitation

• Published in: Agricultural and biological chemistry Vol. 54; no. 5; pp. 1219 - 1225
• Main Authors: Ogawa, H. (Ehime-ken Fruit Growers Co-operative Association, Matsuyama (Japan)), Fukuhisa, K, Kubo, Y, Fukumoto, H
• Format: Journal Article
• Language: English
• Published: Tokyo Taylor & Francis 01.05.1990; Agricultural Chemical Society of Japan
• Subjects: ACIDE ORGANIQUE; ACIDOS ORGANICOS; Biological and medical sciences; CONCENTRACION; CONCENTRATING; CONCENTRATION; ESTERILIZACION TERMICA; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; HEAT STERILIZING; JUS D'ORANGE; MICROORGANISME; MICROORGANISMOS; MICROORGANISMS; ORANGE JUICE; ORGANIC ACIDS; PASTEURISATION; PASTEURIZACION; PASTEURIZING; PECTINESTERASAS; PECTINESTERASE; PRESION; PRESSION; PRESSURE; SATSUMA; SATSUMAS; STERILISATION THERMIQUE; ZUMO DE NARANJA; Heat treatment; Yeast; Enzyme; Citrus fruit; Inactivation; Fruit juice; Pressure; Organic acids; Quality control; Food preservation; PH; Mould; Microorganism; Pectinesterase
• ISSN: 0002-1369
• DOI: 10.1080/00021369.1990.10870118

Satsuma mandarin juice, the concentrated juice and the acid-free juice were prepared and treated with pressures of 1000-6000 bar after mixing with organic acids, various yeasts and molds, or pectinesterase, to study the effects of pressure on inactivation of microorganisms and the enzyme. The effects of heat treatment were also studied in similar conditions. As results, the inactivation effect of pressure on microorganisms and the enzyme was decreased by increasing juice concentration. Pressure-induced inactivation of microorganisms was not affected by either juice pH (between 2.5 and 4.5) or kinds of organic acids (citric, tartaric, lactic, or acetic acid). With 9 species of yeasts and molds tested, pressurization at 3500 bar for 30 min or at 4000 bar for 5 min was required to reduce them to 1/10 5 or below 1/10 5 . Microorganisms resistant to heat tend to be highly resistant to pressure. Although no complete inactivation of pectinesterase was attained after pressurization at 3000 or 4000 bar for 10 min, the partly inactivated enzyme did not recover under ordinary conditions of storage and transportation.