No abstract

This study determined the impact of pasteurization, high-pressure processing (HPP), and retorting on the barrier properties of nylon 6 (N6), nylon 6/ethylene vinyl alcohol (N6/EVOH), and nylon 6/nanocomposite (N6/nano) materials. The pasteurized and high-pressure treated films were coextruded with low-density polyethylene (PE) as the heat-sealing layer. The retorted films were coextruded with polypropylene (PP). Oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) of the samples were measured after pasteurization (75• C for 30 min), HPP (800 MPa for 10 min at 70• C), and retorting (121 • C for 30 min) treatments. These were compared with the thermal characteristics and morphologies of the samples using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Results showed that OTR of N6 and N6/Nano increased after HPP (16.9% and 39.7%), pasteurization (13.3% and 75.9%), and retorting (63.3% and 112.6%), respectively. For N6/EVOH, a decrease in OTR after HPP (53.9%) and pasteurization (44.5%) was observed. The HPP treatment increased the WVTR of N6 (21.0%), N6/EVOH (48.9%), and N6/Nano (21.2%). The WVTR of N6, N6/EVOH, and N6/Nano increased by 96.7%, 43.8%, and 40.7%, respectively, after pasteurization. The DSC analyses showed that the enthalpy and percent crystallinity increased (2.3% to 6.5%) in the N6/Nano when compared with the N6 material after each treatment. Retorting caused a decrease (3.5%) in the percent crystallinity of the polypropylene material. HPP did not cause major morphological changes to the samples. Results of the barrier studies were influenced by the crystallinity changes in the materials as seen in the XRD diffractograms.

A focus group with an educational component was used to help initiate a new research hypothesis. Early‐stage development of a new tamper‐evident invention was improved with input from a consumer focus group. The focus group comprised consumers who were shown several tamper‐evident devices, including a new color‐changing cap under active development. We found that consumers understood tamper‐evident food packaging and recognized when devices were triggered. Most said that they always checked tamper‐evident food packaging but further query revealed that they only did this for certain products. Consumers were ambivalent about paying more for foods protected by tamper‐evident devices, including the color‐changing one. None rejected the color‐changing device but some recommended changes that would improve the invention. Some mentioned that new devices are unnecessary because current technology is effective in keeping food safe. An educational session conducted in conjunction with the focus group sessions showed that some peoples' initial negative attitude changed to positive support for new color‐changing devices after learning about food security concerns. We found that a focus group was useful for shaping academic research and identifying the most practical outcomes. A focus group provided a unique interactive assessment of consumers' understanding of the usefulness and critical research needs in developing a tamper‐evident device.