Milk alternatives – and what is important for their production

This trend has, of course, also impacted the dairy industry. If we look ahead to the near future and at Euromonitor’s forecasts for individual beverage segments, we see that a relatively new product category holds fourth place with a growth rate of over five percent: plant-based drinks (also known as “milk alternatives”).

Filling these products, which may be made from myriad plant sources including soy, oats, spelt, buckwheat, rice, almonds, or other nuts, involves exactly the same technology as dairy milk. Producing them is a different matter entirely.

The process technology makes all the difference 

The main production steps for all milk alternatives are essentially the same: The grains or nuts are milled (either wet or dry) and then filtered or separated before any additional ingredients such as plant oils are blended in. To make the products shelf-stable, they are heat-treated and homogenized, after which they are filled aseptically. 

But it’s not as simple as it sounds. The individual process steps will be quite different depending on the input materials used – whether they are fresh or dried and whether they are whole nuts or grains, meals or flours.

Milling

The first differences emerge at the milling stage: While cereals are usually ground to flour, to which water must be added, materials with more fat content, such as almonds and peanuts, grind to a highly viscous paste.

The milling process itself will vary depending on the raw materials used: The deciding factors here include whether the inputs are dried or fresh, peeled/hulled or whole, that is, with the skins or hulls still on. Some raw materials will be roasted prior to milling. Almonds, for example, are roasted to reduce undesirable constituents such as benzaldehyde.

Preparation

To make further processing easier, many raw materials (including soy, hazelnuts, rice, almonds, and peanuts) are first soaked in water. This step can also help remove unwanted constituents or impurities.

A blanching step may also be added in order to improve the microbiological profile and reduce certain original enzymes. Here, the raw material is briefly heated in water and then immediately cooled.

In the case of cereals, the starch components must first be broken down using hydrolysis. Because the starch is separated into dextrins, this step influences the viscosity of the product by preventing gelatinization. The process also affects the product’s sweetness since the dextrins are separated into the sugars maltose and glucose. 

Unwanted constituents can then be removed or deactivated by subsequent heating of the liquid: For instance, heating can deactivate the lipoxygenase enzymes in soybeans, which are responsible for the typical “beany” flavor. 

Filtration/separation

Both soy and cereals have relatively high fiber content. In order to produce a milk alternative that goes down smoothly, insoluble fibers must be removed in either a decanter centrifuge or a filtration process. Such a process is not necessary for almonds. 

The remaining solids can be dried and pressed and made available to animal feed producers or other users. Some beverage producers of non-dairy drinks collect these fiber residues and feed them back into the manufacturing process for a second extraction to increase yields.

Blending in additional ingredients

Depending on the raw material used, the protein, fat, mineral, or vitamin content will be higher or lower. Thus, makers of plant-based drinks might add plant oils (such as sunflower), vitamins or minerals, or even salt, sugar, or stabilizers to the product.

Heat treatment and homogenization

To make the finished product shelf-stable, heat treatment and homogenization are done before filling. Since most products on the market are shelf-stable and sold at room temperature, they undergo ultra-high-temperature (UHT) pasteurization. Subsequent high-pressure homogenization ensures that any remaining particles are reduced in size, for instance so that fats remain in suspension and do not separate out.

Aseptic filling 

Since plant-based products resemble milk not only in terms of appearance but also in their sensitivity, aseptic filling is necessary to ensure a long shelf life. For this purpose, Krones offers the Contipure AseptBloc DN – proven technology with which to fill plant-based drinks aseptically and reliably.