Effect of biodegradable active packaging with zeolites on fresh broccoli florets

Abstract

Most of the food packaging is mainly petroleum-based, and new forms of food packaging have emerged, such as active, intelligent, and biodegradable packaging to extend the shelf life of fresh vegetables. The aim was to develop a biodegradable active packaging and senescence indicator label for fresh broccoli florets (Brassica oleracea L. var. italica), to increase shelf life and to monitor the decay of the vegetable. The biodegradable active packagings (BAP) were produced by blown extrusion containing zeolite as ethylene scavenger, and their mechanical properties, water vapor permeability, and water sorption isotherms were determined. Fresh broccoli florets were packed in perforated and non-perforated BAP and stored at 12 °C, and their weight loss, vitamin C content, color, and texture were evaluated during the storage. BAPs were efficient in reducing the metabolism of fresh broccoli florets stored at 12 °C, preserving the color, and vitamin C content for 7 days. The senescence indicator labels were able to detect CO₂ in packages without perforations.

Appendix

$$ Xw = {{C.K.mo.aw} \mathord{\left/ {\vphantom {{C.K.mo.aw} {\left[ {\left( {1 - K.aw} \right).\left( {1 - k.aw + C.K.aw} \right)} \right]}}} \right. \kern-\nulldelimiterspace} {\left[ {\left( {1 - K.aw} \right).\left( {1 - k.aw + C.K.aw} \right)} \right]}} $$

(1)

where Xw: equilibrium moisture (gH₂O/g dry basis), C: Guggenheim constant, which represents the heat of adsorption in the first layer, K: heat of sorption of the multilayer, m₀: water content in the monolayer, aw: water activity (RH/100).

$$ \begin{aligned} h^\circ & = tan^{ - 1 } \left( {{\raise0.7ex\hbox{$b$} \!\mathord{\left/ {\vphantom {b a}}\right.\kern-\nulldelimiterspace} \!\lower0.7ex\hbox{$a$}}} \right) \;when \;a > 0 \, e \, b < 0 \\ h^\circ & = 180^\circ + tan^{ - 1 } \left( {{\raise0.7ex\hbox{$b$} \!\mathord{\left/ {\vphantom {b a}}\right.\kern-\nulldelimiterspace} \!\lower0.7ex\hbox{$a$}}} \right) \;when\; a < 0 \\ h^\circ & = 360^\circ + tan^{ - 1 } \left( {{\raise0.7ex\hbox{$b$} \!\mathord{\left/ {\vphantom {b a}}\right.\kern-\nulldelimiterspace} \!\lower0.7ex\hbox{$a$}}} \right) \;when\; a < b \, e \, b < 0 \\ \end{aligned} $$

(2)

$$ \Delta E = \sqrt {\left( {L - L0} \right)^{2} + \left( {a - a0} \right)^{2} + \left( {b - b0} \right)^{2} }^{ } $$

(3)

$$ C* = \sqrt {\left( a \right)^{2} + \left( b \right)^{2} } $$

(4)