Composite nano-structured calcium silicate phase change materials for thermal buffering in food packaging

Effects of the paraffin wax (PW) content on the thermal and permeation properties of the LDPE/PW composite films

“…A drastic rise in temperature causes an increase in the respiratory activity of agricultural products; as a result, low levels of O 2 and high levels of water vapor and CO 2 are generated in the packaging, resulting in microbial spoilage, rancidity, and reduced texture [5,9]. Although packaging materials play a significant role in controlling unwanted temperature changes [5,6,10], unwanted warming continues to occur due to poor insulation, low thermal buffering capacity, and inadequate control of generated gases [6,10]. Packaging materials with a sustainable balance between respiration and gas permeation are needed.…”

“…To enhance the shelf life of food, several studies have been developing packaging materials that are sensitive to temperature and alter their gas permeabilities with increasing temperature [1][2][3][4]. In fact, optimum food quality depends not only on the physiochemical property of food, but also the unwanted temperature variation during storage and distribution, causing product failure through color change, change of respiratory rate, microbial spoilage, and rancidity [5][6][7]. In general, low temperature storage can prolong shelf life by reducing the respiration rate of food such as fruits and vegetables, the growth rates of microorganisms, and various physical and chemical reactions that occur in foods [7,8].…”

Nanotechnologies for Improving Food Quality, Safety, and Security

“…An alternative system based on low -cost materials has been developed by researchers in New Zealand. This system, based on nanoporous calcium silicate, is loaded with a phase -change material (such as paraffi n wax) that can mitigate the effects of an increase in external temperature over a short period of time (fi ve hours), while having similar dimensions to bubble wrap [67] .…”

Nano-Structured Calcium Silicate Phase Change Materials for Packaging Temperature Sensitive Products

“…Effective insulation can alleviate unwanted temperature rises or falls to some extent for a short time. However, this is often insufficient when the packages are exposed to higher or lower temperatures for several hours without effective temperature control (Dodds, 2009;Johnston et al, 2007). New Zealand and other food producing countries export considerable quantities of fresh food to international markets in response to the increasing global demand for such produce.…”

“…The warm temperature fluctuations often encountered are for durations typically up to 1 hour or so, but can be up to several hours, which is sufficient time to cause spoilage of the perishable food in the package. Hence there is a need for an effective material that provides insulation and thermal buffering properties and can be accommodated in readily re-useable liners for inserting into these packages to insulate against and also absorb the transient heat from the external environment, thereby protecting the valuable and perishable products in the package (Amcor Kiwi Packaging Ltd, 2011;Carter Holt Harvey Packaging, 2011;Cool pack, 2011;Johnston and Dodds, 2011;Johnston et al, 2007;Plastics New Zealand, 2011;Powell and Mathews, 1987).…”