From Cheese Whey Permeate to Sakacin A: A Circular Economy Approach for the Food-Grade Biotechnological Production of an Anti-Listeria Bacteriocin

Abstract

Cheese Whey Permeate (CWP) is the by-product of whey ultrafiltration for protein recovery. It is highly perishable with substantial disposal costs and has serious environmental impact. The aim of the present study was to develop a novel and cheap CWP-based culture medium for Lactobacillus sakei to produce the food-grade sakacin A, a bacteriocin exhibiting a specific antilisterial activity. Growth conditions, nutrient supplementation and bacteriocin yield were optimized through an experimental design in which the standard medium de Man, Rogosa and Sharpe (MRS) was taken as benchmark. The most convenient formulation was liquid CWP supplemented with meat extract (4 g/L) and yeast extract (8 g/L). Although, arginine (0.5 g/L) among free amino acids was depleted in all conditions, its supplementation did not increase process yield. The results demonstrate the feasibility of producing sakacin A from CWP. Cost of the novel medium was 1.53 €/L and that of obtaining sakacin A 5.67 €/106 AU, with a significant 70% reduction compared to the corresponding costs with MRS (5.40 €/L, 18.00 €/106 AU). Taking into account that the limited use of bacteriocins for food application is mainly due to the high production cost, the obtained reduction may contribute to widening the range of applications of sakacin A as antilisterial agent.

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

“…Given the potential interest of the active material for food packaging purposes, an estimation of its production cost at laboratory scale is provided. The estimation procedure is based on data from previous sections and follows the methodology used in Musatti et al 3 , based on cost minimization criteria. As a first step, production costs for each component of the active coating formulations were estimated.…”

“…Simulating cost reduction when moving from laboratory to pilot and plant scale is not straightforward 3 . On one side, estimated lab-scale costs do not include energy, labour and fixed costs associated to lab facilities; such omitted inputs would increase production costs at pilot and plant scale.…”

“…Sakacin-A production and enrichment. Cultures (7 L) of L. sakei were carried out in a fermenter (Omnitec Bio, Sedriano, Milano) as reported in Musatti et al 3 . Sakacin-A was quantified in terms of anti-Listeria activity through the agar diffusion assay 31 .…”

“…The combined effect of nutritional properties of WPCs and their cost-efficient production will boost their supply over the next years. Because of an expected increase in demand for WPCs, the availability of CWP is expected to grow at the same pace, representing a valuable resource for circular economy activities 3 .…”

Application of Biotechnological Techniques Aimed to Obtain Bioactive Compounds from Food Industry By-Products

“…In the same vein (non-vegetal by-products), valorization of dairy products keeps improving through the obtaining of attractive ingredients. In this sense, Musatti et al, 2020 [ 10 ], have recently described the application of cheese whey permeate-based culture medium for Lactobacillus sakei with the aim of producing food-grade sakacin A, a bacteriocin exhibiting a specific antilisterial activity. The most convenient formulation was liquid cheese whey permeate supplemented with meat extract (4 g/L) and yeast extract (8 g/L).…”