Interest in starch‐based films has increased precipitously in response to a growing demand for more sustainable and environmentally sourced food packaging materials. Starch is an optimal candidate for these applications given its ability to form thermoplastic materials and films with affordable and often sustainably sourced plasticizers like those produced as waste byproducts by biodiesel and agricultural industries. Starch is also globally ubiquitous, affordable, and environmentally benign. Although the process of producing starch films is relatively straightforward, numerous factors, including starch source, extraction method, film formulation, processing methods, and curing procedures, drastically impact the ultimate material properties. The significant strides made from 2015 to early 2020 toward elucidating how these variables can be leveraged to improve mechanical and barrier properties as well as the implementation of various additives or procedural modifications are cataloged in this review. Advances toward the development of functional films containing antioxidant, antibacterial, or spoilage indicating components to prevent or signal the degradation of food products are also discussed.
Food quality monitoring, particularly, the detection of bacterial pathogens and spoilage throughout the food supply chain, is critical to ensure global food safety and minimize food loss. Incorporating sensors into packaging is promising, but it is challenging to achieve the required sampling volume while using food‐safe sensor materials. Here, by leveraging water‐based processing of silk fibroin, a platform for the detection of pathogenic bacteria in food is realized using a porous silk microneedle array; the microneedle array samples fluid from the interior of the food by capillary action, presenting the fluid to polydiacetylene‐based bioinks printed on the backside of the array. Through the colorimetric response of bioink patterns,
- NSF-PAR ID:
- 10449755
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 31
- Issue:
- 1
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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