Water plays a crucial role in agro-industrial processes. It is one of the main ingredients in food, also used for
heating, cooling, or preserving, or in cleaning operations on food, machinery, or production areas to guarantee
food safety. The increase in food production to meet population growth causes a dramatic surge in water
consumption in food processing.
Each type of commodity and food shows a water footprint that characterizes its sustainability regarding the
water consumption necessary for its transformation and production. Furthermore, the more food is processed
and handled, the greater its water footprint will be, as each processing step and co-product production (e.g.,
additional ingredients or packaging) may need water (Mekonnen & Gerbens-Leenes, 2020). The food and
beverage industry has a strong impact on water resources, consuming almost 3% of the world’s water supply.
Three ways to manage water for food production are possible: Reduce water consumption, Reuse and
recycle wastewater, Use of alternative water sources. Various methods are available depending on water quality
requirements, space, and budget constraints (Shrivastava et al., 2022).
Membrane technologies are an effective tool to recycle wastewater or make alternative water sources
suitable for industrial processes. Membrane separation techniques allow the recovery of water otherwise lost,
while concentrating and purifying valuable compounds (Pervez et al., 2021).
Membrane processes are included in the Best Available Techniques (BAT) (Joint Research Centre, 2018).
They are mild, non-destructive, and energy-efficient methods, suitable to treat liquid by-products deriving
from food processing, such as olive mill wastewater, dairy wastewater, brewery wastewater, and blanching
water (e.g., from the almond, tomato, or potato processing industry). Micro-, ultra-, and nano-filtration can be
used sequentially to separate and concentrate the solutes from the aqueous fraction. Reverse osmosis systems
can intervene downstream of these treatments to obtain purified water.
The benefits of these treatments include the reduction of wastewater flows, freshwater costs, and the water
footprint of the entire process. The recovered water can become an ingredient for new food products and, at the
same time, valuable compounds, such as polyphenols, carotenoids, and nutrients, can be recovered and used in
other industrial sectors, thus adding value to the food system.