Scaling up continuous eutectic freeze crystallization of lactose from whey permeate: A pilot plant study at sub-zero temperatures

[Display omitted] •Simultaneous crystallization of lactose and water at sub-zero temperatures.•Lactose is crystallized and recovered in a continuous eutectic freeze pilot plant.•Freeze concentration is possible up to 30 wt% lactose producing high purity ice.•Ice was recovered at a rate of 60 kg/h an...

Full description

Saved in:
Bibliographic Details
Published in:Food research international 2023-06, Vol.168, p.112764-112764, Article 112764
Main Authors: Halfwerk, Ruben, Verdonk, Louise, Yntema, Doekle, Van Spronsen, Jaap, Van der Padt, Albert
Format: Article
Language:English
Subjects:
Continuous crystallization
Crystallization - methods
Eutectic freeze crystallization
Freeze concentration
Freezing
Ice - analysis
Lactose
Lactose - chemistry
Mechanical vapor recompression
Pilot plant
Temperature
Whey - chemistry
Whey permeate
Whey Proteins - chemistry
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:[Display omitted] •Simultaneous crystallization of lactose and water at sub-zero temperatures.•Lactose is crystallized and recovered in a continuous eutectic freeze pilot plant.•Freeze concentration is possible up to 30 wt% lactose producing high purity ice.•Ice was recovered at a rate of 60 kg/h and lactose was recovered at a rate of 16 kg/h.•EFC was found to be 30–80% more energy efficient compared to evaporation. Eutectic freeze crystallization is explored as an alternative to the state-of-the-art evaporation process for the recovery of lactose from whey permeate. At the so-called eutectic freezing point, both water (the solvent) and lactose (the solute) crystallize and can be removed continuously while continuously feeding whey permeate. This continuous process is demonstrated on a pilot scale at sub-zero temperatures. In the first instance, only freeze concentration of whey permeate took place at −4 °C. It was possible to reach a lactose concentration of 30 wt% and hardly any nucleation was observed. The resulting ice had high purity, with a lactose concentration of ±2 wt%. Next, the eutectic phase was reached, and lactose and ice crystallized simultaneously and were continuously removed from the system, the resulting crystals had parallelogram morphology with an average size of 10 µm. Ice was recovered at a rate of 60 kg/h and lactose was recovered at a rate of 16 kg/h, yielding over 80% of the feed lactose. A conceptional design was proposed for an improved yield and reduction of energy. Yields of at least 80% and up till 95% could be achieved. Compared to the state-of-the-art mechanical vapor recompression (MVR), EFC is 80% more energy efficient.
ISSN:0963-9969
1873-7145
DOI:10.1016/j.foodres.2023.112764