Methods for Measurement of Gas Volume of Fruits and Vegetables

Abstract

<jats:p>Theory is presented for a differential mass-volume technique to measure non-destructively gas volume (V<jats:sub>g</jats:sub>) changes, based only on the initial and final masses and volumes of an organ. Volume was measured using Archimedes' principle, but a non-invasive image analysis procedure could be an improvement. A reduction in V<jats:sub>g</jats:sub> during the ripening of `Kada' tomato <jats:italic>(Lycopersicon esculentum</jats:italic> Mill) fruits, and irreversible V<jats:sub>g</jats:sub> changes of 0.02, 0.29, 0.66, 1.2, and 1.3 ml for mature-green fruits compressed by 0, 2.5, 5.0, 7.5. and 10 mm for 5 minutes indicates the potential of this procedure. The method was compared with other methodologies using sweetpotato <jats:italic>(Ipomea batatas</jats:italic> L.) root segments subjected to vacuum water infiltration. The results were similar to the pycnometric method. The gasometric method underestimated V<jats:sub>g</jats:sub> for roots in which the intercellular air volumes where blocked by the water used for infiltration, and large overestimation occurred with the traditional infiltration technique without correction for water absorption. Absolute V<jats:sub>g</jats:sub> values were also estimated by semi-pycnometry (defined as the difference between the organ volume measured by water immersion and the organ volume without V<jats:sub>g</jats:sub> measured with a pycnometer, after its maceration and elimination of gas bubbles with vacuum). Semi-pycnometry applied to tomato and bell pepper <jats:italic>(Capsicum annuum</jats:italic> L.) fruits, where the use of tissue segments limits the pycnometric method, and in sweetpotatoes, where the gasometric method overestimates V<jats:sub>g</jats:sub>, generated results that were consistently similar to the differential mass-volume method.</jats:p>

Effects of modified atmosphere packaging on quality attributes and physiological responses of fresh-cut crisphead lettuce

“…O 2 concentration was measured in a Facili equipment according to Thoday (1913), modified by Calbo and Nery (1995). The results were expressed in %O 2 .…”

Adapting Constant-volume Manometry for Studying Gas Exchange by Bulky Plant Organs

“…Intercellular gas determinations. V G was estimated with a semipycnometric method (Calbo and Nery, 1994).…”

Texture analysis of blanched vegetables using high- and low-speed measuring methods

“…The differences in the measured textural characteristic between celeriac and pota-IJFS April 2017 Volume 6 pages 1-12 toes or carrots are caused by their structure and composition. Celeriac has a sponge-like structure with a high amount of intercellular spaces in comparison with the relatively low amounts of intercellular spaces of potatoes and carrots (Calbo & Nery, 1995;Slaska-Grzywna, 2010;Hudson, 1975). Hence, it is assumed that cooking water can move directly to the cells at low cooking times (e.g.…”