Plant-based milk is the largest plant-based category in North America, and grew 5% last year, with sales of plant-based dairy products approaching $2 billion.
In fact, the plant-based milk market now accounts for around 10% of the total milk market, and the growing number of consumers of plant-based milks have more choice than ever before. The most popular plant-based milk in North America is currently almond milk (which occupies almost two-thirds of the market), followed by oat milk (the fastest-growing product type), and soy milk. However, the sector is full of innovation, with new developments and products plant-based milk alternatives, or ‘alt-milks’ as they are sometimes known, are being made from more raw ingredients than ever before, with pea- and barley-based drinks being among the most recent newcomers to the market.
There are many reasons for the popularity of plant-based milks. As well as a rise in the adoption of vegan and plant-based diets due to health and moral grounds, environmental concerns are also driving uptake with proponents claiming that plant milk has a lower greenhouse gas (GHG) footprint than dairy production – although the overall picture is highly complex, and the figures are disputed by the dairy industry. An apparent increase in the level of lactose intolerance in developed countries is also helping to increase demand.
The range of plant-based milks also allows for consumers to express their tastes and identities as cafes and restaurants open-up after lockdown. As one industry analyst said earlier this year, “To choose your specific type of plant-based milk in Starbucks seems to be a way of identifying yourself.”
While dairy milk has long been seen as a drink or a meal accompaniment, for example being used as an ingredient or with cereal, there are increasing signs that plant-based drinks, particularly those with a thicker more yogurt-like texture or those sold in individual portions, are being seen as a healthy snack. Research by the Brisan Group1 suggests that up to a third of these products are viewed as a snack, and 61 percent are viewed as ‘a treat.’
Globally soy milk products remain the most popular (although the demand for oat-based products is growing) and they accounted for 29.5% of revenue globally in 2019. Coconut-based beverages are one of the fastest-growing segments, predicted to increase 8.6% between 2020 and 2027. Across all types of plant-milk, plain flavours dominate sales, accounting to 71.1% of the total value.
Production of plant-based milk
Contrary to public perception, the idea of plant-based milks is not new. ‘Milk’ made from soybeans has a long history in China (where recorded production dates to 1365), while almond milk was recorded in the Middle East in the 13th century. A commercial soy milk factory was established near Paris in 1910 and demand for soy milk rose through the 1970s and 80s due to increasing awareness of lactose intolerance.
These days there is a wide range of plant-based milks made from nuts, grains, and legumes, as well as other seeds (such as sunflower and hemp) or coconut.
There are two main methods for processing plant-based milk: wet or dry. The wet process involves soaking and grinding the raw material in large volumes of water for up to 12 hours. In some cases, enzymes are added to hydrolyze starches (for example in oat milk production). The dry process involves milling the raw material into a flour or powder which is then processed to separate the starch, protein, and fiber as desired, before being hydrated. As a result, dry production processes can result in a higher protein content in the finished product.
The production method means that, if the soaked product is not ground to sufficiently fine a size, the number of particles removed when the mixture is strained creates high levels of waste. It is also important to mix products well, particularly those containing oils or thickening or stabilizing agents. Therefore, maintaining product consistency is a key goal for the manufacturing process, and will determine the choice of processing equipment including pumps, heat exchangers, etc.
Disadvantages of plant-milk
Plant-based milks cannot match the natural nutrition profile of dairy milk in terms of protein levels and essential amino acids. However, as well as being free of lactose, they are lower in saturated fat and cholesterol than non-skimmed milk.
Plant-based milks are not immune from criticism, and in some countries and regions, including the European Union, such products cannot be sold or marketed as ‘milk’ or ‘yogurt.’ In addition, supporters of dairy milk say plant-based drinks are highly processed and full of additives, while diary milk is simply homogenized and pasteurized.
Despite this, such is the interest in the sector than many of the world’s largest dairy companies, including Lactalis, Nestlé and Danone, are investing into dairy-alternatives, either through product development or company acquisition. Several market analysts believe the market is ready for rationalization, with several brands falling by the wayside or being acquired by larger food producers.
Maintaining quality and demand
The quality of the product is very important, and monitoring of key parameters includes viscosity, particle size, protein content, digestibility, nutrient content, and flavor analysis. Maintaining these important quality characteristics requires the minimal amount of processing – and making sure that processes such as pasteurization cause as little disruption to the product as possible can help alleviate criticisms about the highly processed nature of plant milks.
Where possible, combining processes such as dilution and sterilization, for example by using the HRS DSI Series, can provide benefits and reduce overall processing of the product. The benefit of sterilizing using direct steam injection is the speed of the process, with sterilization temperatures of 100 to 145 deg. C. being reached in around a second; much quicker than the fastest heat exchanger systems. For products such as plant milks, this rapid heating prevents cooking of the product and formation of caramel-type compounds which can darken the product or produce unwanted flavors.
It is also useful for grain-based products, such as oat milk, which benefit from the additional dilution with water which the food-grade steam provides, but the type and model of heat exchanger chosen will depend on many different factors, such as the nature of the process to be carried out (pasteurization, sterilization, dehydration, etc.) and the viscosity of the drink being processed. HRS has a complete range of products from simple tube-in-tube designs to rotating or reciprocating scraped-surface designs, all of which combine efficient heat transfer with delicate product handling; ensuring that products remain in emulsion and that the product does not foul the equipment.
The final word
Whatever plant-based milk product you are producing, it is important to remember that plant-based milks have the same requirements for pasteurization, sterilization, cooking or cooling as other beverages which contain specific ingredients. It is therefore crucial to invest in the most effective and efficient processing technology for all stages of production.
Matt Hale is International Sales & Marketing Director for HRS Heat Exchangers. Located in Atlanta, HRS Heat Exchangers is part of the HRS Group which operates at the forefront of thermal technology, offering innovative heat transfer solutions worldwide across a diverse range of industries. With 40 years’ experience in the food and beverage sector, specializing in the design and manufacture of an extensive range of turnkey systems and components, incorporating our corrugated tubular and scraped surface heat exchanger technology, HRS units are compliant with global design and industry standards.