Recovery and reincorporation of milk concentrate from acid whey
Acid whey, a by-product of cottage cheese and Greek yoghurt manufacture, is a nutrient rich liquid, containing whey protein, lactose, lactic acid, and minerals. The acidity level, presence of organic acid and high levels of minerals in acid whey, compared to sweet whey, poses several processing challenges and thus it is generally discarded as food waste and has been identified as a significant food waste hotspot (FIAL, 2021).
Currently, this waste is disposed of as cattle feed and by spraying on farmlands as a fertiliser, imposing transportation costs, greenhouse gas emissions and a negative environmental impact due to the acid whey’s high biological oxygen demand. Due to the high lactic acid content and low pH, it is difficult to process acid whey as most of the lactose remains in an amorphous, sticky state leading to caking and agglomeration of the final material. The high content of calcium phosphate also results in extensive fouling of processing equipment
Bulla Dairy Foods, in collaboration with RMIT and Fight Food Waste CRC, will aim to develop a commercially viable method to neutralise and concentrate acid whey, prior to its reincorporation in novel product formulations. The recovered acid whey will be used to produce food products or ingredients with a high level of food safety. The acid whey neutralisation and concentration will take place in Bulla’s accredited food production facilities by their experienced production and QA teams, using food grade ingredients. The research will then be conducted at RMIT.
The three key aims of this project are:
- Optimise the process of neutralising, concentrating and recovering acid whey components.
- Develop a range of value-added dairy-based food products using acid whey with the required textural properties.
- Achieve a desirable level of sensory acceptability by the consumer in acid whey containing dairy products.
FIAL, 2021. The National Food Waste Strategy Feasibility Study – Final Report.
Project start date: 01/05/2023
Project end date: 30/04/2024
Stefan Kasapis, RMIT