From cheese whey permeate to Sakacin-A/bacterial cellulose nanocrystal conjugates for antimicrobial food packaging applications: a circular economy case study

Abstract

Applying a circular economy approach, this research explores the use of cheese whey permeate (CWP), by-product of whey ultrafiltration, as cheap substrate for the production of bacterial cellulose (BC) and Sakacin-A, to be used in an antimicrobial packaging material. BC from the acetic acid bacterium Komagataeibacter xylinus was boosted up to 6.77 g/L by supplementing CWP with β-galactosidase. BC was then reduced to nanocrystals (BCNCs, 70% conversion yield), which were then conjugated with Sakacin-A, an anti-Listeria bacteriocin produced by Lactobacillus sakei in a CWP based broth. Active conjugates (75 Activity Units (AU)/mg), an innovative solution for bacteriocin delivery, were then included in a coating mixture applied onto paper sheets at 25 AU/cm2. The obtained antimicrobial food package was found effective in reducing Listeria population in storage trials carried out on a fresh Italian soft cheese (named “stracchino”) intentionally inoculated with Listeria. Production costs of the active material have been mainly found to be associated (90%) to the purification steps. Setting a maximum prudential 50% cost reduction during process up-scaling, conjugates coating formulation would cost around 0.89 €/A4 sheet. Results represent a practical example of a circular economy production procedure by using a food industry by-product to produce antimicrobials for food preservation.

Use of Lactobacillus for Lactic Acid Production from Agro-Industrial By-Products

“…This favorable impact, sought by the United Nations with the fulfillment of the Sustainable Development goals proposed for the year 2030, can also be reflected in the valorization of agro-industrial by-products not only to produce lactic acid but also in other applications. Examples of these applications are nutraceutical formulations and pharmaceuticals through the use of fungal co-products [56], food packaging through the use of whey [57], valorization of lard through biotechnological tools employing fermentation in state solid of Yarrowia lipolytica and Lacticaseibacillus paracasei [58], biorefining of whey…”

Cost-Effective Synthesis of Bacterial Cellulose and Its Applications in the Food and Environmental Sectors

“…Rollini et al synthesized bacteriocin sakanin-A/BC nanocrystals and studied their application as antibacterial food packaging. The bacteriocin was prepared from cheese whey protein (CWP), a cheap substrate obtained as a by-product, thus proposing an economic approach for active packaging [ 148 ]. Castro et al loaded curcumin and carvacrol onto cyclodextrin (CD)-grafted TEMPO-oxidized cellulose nanocrystals (TOCNCs).…”

Novel Probiotic/Bacterial Cellulose Biocatalyst for the Development of Functional Dairy Beverage

“…The primary purpose is to use cheese whey lactose, as a carbon source, to replace the conventional and expensive synthetic media that are usually applied in bioconversion processes. On top of that, the expanding interest for whey proteins enables circular economy strategies [ 25 , 26 ]. According to recent market reports, worldwide permeate market (obtained from milk or whey) is expected to reach US $1.29 billion by 2032, driven by the increasing demand for it as a food supplement [ 27 ].…”