• Mechano-bactericidal (MB) nanostructured food contact surfaces.

As the high-speed automation of food production expands, the number of abiotic surfaces with which foods come into contact, and hence the risk of cross-contamination, rises. Advances in nanofabrication and nanoengineering facilitated the development of nanopatterned surfaces with surface topographies reminiscent of those found in nature that fend off microbial invasion by rupturing cells physico-mechanically, without releasing biocides into adjacent food matrices. Despite the antimicrobial potential of these MB surfaces, their implementation in the food industry as a solution for improving food safety and quality is hindered by a unique set of challenges, including scalability, cost-effectiveness, mechanical and chemical durability, and complex food matrix composition. We aim to integrate these MB nanopatterns onto both stiff and flexible FCS via electrochemical anodization and nanoimprint lithography, respectively, in a cost-effective and scalable manner.

• Directing bacterial behaviors via surface-embedded cues

Designing biointerfaces with physicochemical features that reduce initial bacterial attachment, which is arguably the first and most vulnerable step in the biofilm cycle, is one such preventative strategy for combating biofilms. Nonetheless, despite decades of research on material properties and anti-attachment performance, our fundamental understanding of such relationships has been hindered by contradicting trends. One root cause of such contradiction is the insufficient decoupling of the effects of key physicochemical features such as surface topography, chemistry (including charge and surface energy), and mechanics (e.g., stiffness) on bacterial attachment, due at least in part to fabrication challenges and the lack of a comprehensive theoretical framework. We aim to use the ONE platform as well as data-driven methods to decouple the effects of these important surface properties on bacterial attachment and biofilm formation. Such fundamental understanding will guide the rational design of material surfaces that can direct bacterial behaviors including attachment/detachment, multiplication, and biofilm formation.

• "Polymer Jacket" for Enzymes to Expand their Comfort Zones

One prominent barrier to expanding the use of enzymes for food processing or food waste valorization is their relatively narrow windows of conditions for achieving optimal activities. For example, although lactose-rich acid whey represents an “untapped goldmine” for enzymatic waste valorization using lactase, there is the mismatch between the optimal pH of free/soluble lactase (~7) and that of acid whey (~4), which impairs the activity and stability of the enzymes. To overcome this barrier, we use the ONE platform to engineer enzyme microenvironments that serves to promote the activity and stability of the enzymes in challenging feed conditions (e.g., high temperature or low pH) — just like putting a protective jacket around the vulnerable enzymes. This way, the same enzymes can stay functional for longer time in conditions otherwise too harsh for them to tolerate and perform.

• Enzymatic Membrane Reactors

Building upon the abovementioned engineering of chemical microenvironments, immobilization of enzymes onto the pore walls of AAO membranes via iCVD nanolayers would lead to enzymatic membrane reactors that are fully compatible with continuous feed conversion. The immense specific surface area offered by AAO membranes would allow extraordinary enzyme loading; meanwhile, the spatial nanoconfinement imposed by the AAO nanopores could increase the probability of substrate-enzyme binding – both would promote the efficiency of feed conversion. Moreover, theoretical calculations suggest that nanoconfinement holds the promise to make unfolding of enzymes under higher temperature less energetically favorable, thus promoting heat stability. Altogether, the ability to control the chemical and physical microenvironment orthogonally will drastically improve our capability to design efficient and resilient enzymatic membrane reactors for challenging feeds.

Recently, advances in sensors miniaturization, radio frequency identification (RFID), and blockchain technologies have unveiled a promising future of internet of things (IoT) throughout the farm-to-fork continuum. One exciting prospect brought by this powerful union is smart expiration date (e.g., smart “use-by” or “best-by” dates), whereby pre-fixed expiration dates printed on food packaging would be replaced by dynamic expiration dates, determined through monitoring physicochemical properties of the packaged food. This change has the potential to dramatically reduce food waste throughout the food supply chain by: (i) avoiding throwing away “expired” food that are still suited for consumption by consumers; (ii) enabling more efficient inventory management and promotion (e.g., dynamic discounts) at the retail store level; (iii) promoting the transition from a “push” system to a “pull” system at the food production and manufacturing level, i.e., the manufacturers plan their production based on real-time sales outcome. We aim to turn fibrous materials derived from food processing by-products (e.g., the fiber-rich portion of grape pomace) into low-cost electrical sensors, for monitoring characteristic molecular indicators for spoilage or ripening. iCVD nanocoating over cellulose or pectin fibers would allow selective permeation of target gas molecules (e.g., biogenic amines), through rational design of the surface energy, charge, and porosity of the iCVD nanolayer. With the near-zero-cost fibers derived from by-products and the excellent scalability of iCVD (e.g., it is compatible with roll-to-roll processes), the cost of such gas sensors could be lowered enough for integration with the primary packaging of perishable foods