Ripening and development of chilling injury in persimmon fruit: An electrical impedance study

Abstract

Electrical impedance spectroscopy was used to follow ripening and chilling injury development in persimmon fruit (Dyospyros kaki L. 'Fuyu'). Tissue resistance and reactance were measured at frequencies between 50 Hz and 1 MHz, and then fitted to an electrical model. Fruit responses to both ripening at 20°C and storage in modified atmosphere at 7°C were distinct and easily detected using electrical impedance spectroscopy. Plots of reactance against resistance at each series of frequencies traced a semicircular arc. During ripening, the arcs dilated between Days 1 and 21, then contracted, until at Day 35 they were smaller than at Day 1. Electrical modelling indicated that the dilation occurred as a result of a 43, 115, and 17% increase in resistance R\ (cell wall resistance), R 2 (cytoplasm resistance), and R 4 (vacuole resistance), respectively. After 35 days of ripening, R 1 was 39% lower and C 3 (membrane capacitance) was 19% higher than at Day 1. Chilling injury developed with increasing time at 7°C in modified atmosphere storage (MA), until severe symptoms were observed after 5 weeks. Chill-injured fruit differed from other fruit in that R2 was significantly lower upon removal from storage, although it rapidly increased when fruit were transferred to 20°C for ripening. These results are discussed in relation to the physiological changes that occur during ripening and development of chilling injury in persimmon.

Electrical impedance spectroscopy (EIS) for biological analysis and food characterization: a review

“…To test how the chilling injury induced by cool storage affects the fruit electrical parameters during ripening, a set of fruits was stored at 0 • C for several weeks and then monitored during the ripening process at 20 • C: this resulted in a much more limited variation of the resistance measured at 50 Hz during the ripening process. Harker and Forbes (1997) published the results of a similar experiment carried out on persimmons (cultivar Fuyu) using the same experimental setup. In this case too, only the resistance at low frequency (50 Hz) was influenced by the ripening process at 20 • C, but the resistance at 50 Hz increased in the first 21 days and then decreased until day 35 (at the end of the ripening reaching a value lower than at day 0).…”

Estimating pressure induced changes in vegetable tissue using in situ electrical conductivity measurement and instrumental analysis

“…In freeze-thawed vegetable tissues, cell membranes and associated compartments are disrupted. This leads to a dramatic change in electrical impedance characteristics in the plant tissues; most of the reactance component is lost, and the resistance declines dramatically (Harker and Dunlop, 1994;Harker and Forbes, 1997;Jackson and Harker, 2000). These phenomena propose extensively increased electrical conductivity of freeze and thawed vegetables.…”

Nondestructive Evaluation of Food Quality

“…Later radio-frequency (RF) measurements (Kim et al 2003, Nelson and Payne 1982, Nelson and Whitney 1960, Wang et al 2006a, changes in the capacitance of sample-holding capacitors, when grain samples were introduced between the capacitor plates, were correlated with grain moisture content and used for grain moisture measurement (Nelson 1996(Nelson , 2006. Majority of the food materials, including oils and fat (Cataldo et al 2010, Pace et al 1968, Lizhi et al 2010, El-shaml et al 1992, Carey and Hayzen 2008, Fritsch et al 1979, Hein et al 1998, Inoue et al 2002, meat and poultry (Basaran et al 2010, Li and Barringer 1997, Ragni et al 2007, Castro-Giráldez et al 2010, Ghatass et al 2008, fruits and vegetables (Garcia et al 2001, Gordeev 1998, Guo et al 2007a, Harker and Dunlop 1994, Harker and Forbes 1997, Harker and Maindonald 1994, Inaba et al 1995, Maezawa and Akimoto 1996, Nelson 1980, 2008, Nelson et al 2007, 2006, Tran et al 1984, Varlan and Sansen 1996, Bauchot et al 2000 and dairy products (Nunes et al 2006, Kudra et al 1992, O'Connor and Synnot 1982…”