Predicting Steady-state Oxygen Concentrations in Modified-atmosphere Packages of Tomatoes

Abstract

<jats:p>Mathematical procedures for predicting steady-state O<jats:sub>2</jats:sub> concentrations for a range of packaging conditions for modified-atmosphere packages (MAP) of `Heinz 1370' tomato (<jats:italic>Lycopersicon esculentum</jats:italic>) were developed and tested. The relationship between O<jats:sub>2</jats:sub> consumption rate and O<jats:sub>2</jats:sub> concentration was determined using O<jats:sub>2</jats:sub> depletion data collected by enclosing tomatoes in jars and sampling head space O<jats:sub>2</jats:sub> concentration over time. The fitted function was then used in conjunction with the input variables film permeability to O<jats:sub>2</jats:sub> (P<jats:sub>O2</jats:sub>), film surface area (A), and fruit weight in packages (W<jats:sub>p</jats:sub>) to develop an equation to predict steady-state O<jats:sub>2</jats:sub> concentrations for different packaging ratios (A/W<jats:sub>p</jats:sub>) and film permeabilities. Prediction curves showing steady-state O<jats:sub>2</jats:sub> concentration for packaging ratios in the range of 1 to 12 closely resembled best-fit curves of experimental data. Increasing temperature from 20 to 28C had little effect on in-package O<jats:sub>2</jats:sub> concentration, but decreasing temperature from 28 to 10C led to higher in-package O<jats:sub>2</jats:sub> concentrations. The predictive equation developed can be used to select appropriate films and optimize packaging ratios to achieve desired steady-state O<jats:sub>2</jats:sub> concentrations for MAP of tomatoes.</jats:p>

Influence of a commercial warm chlorinated water treatment and packaging on the shelf-life of ready-to-use lettuce

“…This model is obviously a simplification of a more complex system and is based on one limiting enzyme reaction of which the substrate is O 2 (Fonseca et al, 2002). Other more empirical approaches include quadratic (Gong & Corey, 1994) and exponential (Cameron, Boylan-Pett, & Lee, 1989;Smyth et al, 1998) equations.…”

Use of endospore-forming bacteria as an active oxygen scavenger in plastic packaging materials

“…levels of 0.6-0.7 ml. In many cases a Michaelis-Menten type equation, based upon enzymatic kinetics, is used to describe respiration kinetics and the dependence of O 2 concentrations on respiration rate (Gong & Corey, 1994;Jin & Bethke, 2007). However, no satisfactory linear relationship was found here after transforming the measured data to a Lineweaver-Burke plot between the reciprocal values of both the oxygen absorption rate and the oxygen concentration (Fig.…”

Modeling the effect of storage temperature on the respiration rate and texture of fresh cut pineapple

“…Instead, a regression function is often used to fit the data of gas concentrations only as a function of time (Gong and Corey, 1994;Hagger et al, 1992;Jacxsens et al, 1999). Fig.…”

“…The derivatives of Eqs. (16) and (17) were used to calculate the respiration rates following the three step method proposed by Gong and Corey (1994). The respiration rate can be expressed as only a function of gas concentrations:…”

“…The free volume of the jars and the weight of the pineapple taken for verification were 803.67 ml and 202.02 g, respectively. The experimental respiration rates of the pineapple at 15°C were determined using the method proposed by Gong and Corey (1994) and the predicted respiration rates were calculated with the model parameters gave in Table 4. The mean relative modulus and correlation coefficients were 3.86% and R 2 > 0.997 for R O2 and 18.34% and R 2 > 0.992 for R CO2 , thus confirming the predictive ability of the model (E < 20%).…”