Cold Microfiltration as an Enabler of Sustainable Dairy Protein Ingredient Innovation

Abstract

Classically, microfiltration (0.1–0.5 µm) of bovine skim milk is performed at warm temperatures (45–55 °C), to produce micellar casein and milk-derived whey protein ingredients. Microfiltration at these temperatures is associated with high initial permeate flux and allows for the retention of the casein fraction, resulting in a whey protein fraction of high purity. Increasingly, however, the microfiltration of skim milk and other dairy streams at low temperatures (≤20 °C) is being used in the dairy industry. The trend towards cold filtration has arisen due to associated benefits of improved microbial quality and reduced fouling, allowing for extended processing times, improved product quality and opportunities for more sustainable processing. Performing microfiltration of skim milk at low temperatures also alters the protein profile and mineral composition of the resulting processing streams, allowing for the generation of new ingredients. However, the use of low processing temperatures is associated with high mechanical energy consumption to compensate for the increased viscosity, and thermal energy consumption for inline cooling, impacting the sustainability of the process. This review will examine the differences between warm and cold microfiltration in terms of membrane performance, partitioning of bovine milk constituents, microbial growth, ingredient innovation and process sustainability.

Protein Preparations as Ingredients for the Enrichment of Non-Fermented Milks

“…In milk enriched with whey proteins, α-lactalbumin and β-lactoglobulin accounted for up to 45% of TP, and their content was highest in milk with the addition of WPI (Figure 3). Membrane fouling is more extensive when dairy streams are filtered at higher processing temperatures (45-55 • C) when whey proteins, in particular β-lactoglobulin, are partially unfolded and intensify protein-protein interactions [33]. Moreover, this temperature range facilitates protein-protein and protein-membrane interactions with the participation of divalent cations (Ca 2+ ) [32].…”

Production, composition and preservation of micellar casein concentrate and its application in cheesemaking: A review

“…Cold MF is considered to have a lower impact on the environment in terms of reduced consumption of water and cleaning agents (Schiffer and Kulozik 2020; France et al . 2021). For cold MF applications targeted at isolating serum proteins instead of β‐casein from the feed milk, subjecting the feed milk to heat treatment or adding calcium chloride to feed milk prior to processing can effectively decrease the release of casein monomers from casein micelles to the milk serum phase, and ultimately increase the purity of whey protein in the permeate (Schiffer, Adekunle, et al .…”

“…In comparison to ceramic membranes, polymeric membranes are less efficient in excluding serum protein from retentate (Zulewska and Newbold 2009; France et al . 2021), and have less stability to chemicals and heat (Baruah and Nayak 2006; Karasu et al . 2010).…”

Recent Advances and Trends in the Dairy Field

“…This technology that separates the particles according to their size can also fractionate casein micelles from whey proteins using ultrafiltration membranes. Conducting the microfiltration process at warm temperatures decreases the viscosity and improves the transfer properties at the cost of microbial quality and some issues with fouling, so cold microfiltration has been studied as an alternative [10]. All of the relevant conditions that can affect the performance of microfiltration were reviewed by France et al [10].…”

“…Conducting the microfiltration process at warm temperatures decreases the viscosity and improves the transfer properties at the cost of microbial quality and some issues with fouling, so cold microfiltration has been studied as an alternative [10]. All of the relevant conditions that can affect the performance of microfiltration were reviewed by France et al [10]. The differences between warm and cold filtration received special attention in this review, in particular the effects on microbiology and fouling.…”