Characterization of Mg2+-induced bitter pit-like symptoms on apples: a model system to study bitter pit initiation and development

• Published in: Journal of agricultural and food chemistry 1993-08, Vol.41 (8), p.1203-1207
• Main Authors: Burmeister, D.M, Dilley, D.R
• Format: Article
• Language: English
• Subjects: AHOYADO AMARGO; Biological and medical sciences; BITTER PIT; CALCIO; CALCIUM; CATION; CATIONES; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; MAGNESIO; MAGNESIUM; MANZANA; METAL; METALES; MODELE; MODELOS; POMME
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf00032a007

Vacuum infiltration of MgCl2 solutions into intact apple fruits induces bitter pit-like symptoms [Mg2+-induced pits (MgIP)]. Including Ca2+ in the infiltration media prevents MgIP. Golden Delicious apple fruit were infiltrated with various concentrations of Ca2+ and Mg2+ with and without Ca2+-affecting reagents or other cations. Including trifluoperazine with Mg2+ increased pitting over that with Mg2+ alone. Verapamil and nefedipine had no effect on MgIP or its attenuation by Ca2+. Cyclopiazonic acid attenuated MGIP. Ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid and 2,3,5-triiodobenzoic acid attenuated MgIP. Cycloheximide and actinomycin D inhibited MgIP, while puromycin had no effect. Heating fruits at 38 degrees C prior to infiltrating the fruits with MgCl2 attenuated MgIP. Cations Ba2+, La3+, Co2+, and Sr2+ included at 20.0 mM prevented MgIP (induced by 0.18 M Mg2+). Ca2+ (3.0 mM) included with 0.18 M Mg2+ inhibited MgIP 50%. K+ and Na+ partially inhibited MgIP. We have demonstrated that treatments affecting calcium homeostasis or cellular metabolism can alter MgIP development. We conclude that MgIP may be a useful tool to understanding natural bitter pit development