Course:FNH200/Projects/2022/Plant-Based Milk

Introduction

Considering the rising concern of the saturated fat content in milk and the growing ethics of a plant-based diet, the recent 2019 revision to Canada’s Food Guide has placed emphasis on plant-based sources of protein, greatly reducing the importance of milk. Our project highlights the growing demand of plant-based milk alternatives by consumers due to various reasons. We will also explore the general processing methods of plant-based milk. Being aware of the nutritional value of dairy milk, governments and manufacturers are using fortification as a means to make plant-based milk, not just a palatable alternative, but also a nutritional alternative to dairy milk.

The Growing Demand

Plant-milks such as almond milk, oat milk, and soy milk, have been rapidly gaining popularity and attention. This rapid increase in popularity and attention has been accelerated by the pandemic, as more people started drinking coffee at home and replicated the choice in milk options from their favourite cafes. Regardless, the main reasons for the preference of plant-milks over dairy milks remained unchanged: ~16% of Canadian adults are lactose-intolerant and ~1/5 of Canadians are choosing plant-based diet or limiting meat consumption.  Main 2 reasons for the plant-milks gaining traction are the environmental impact and animal welfare. The rise in adoption of vegan/plant-based diets due to health reasons, moral grounds, and environmental concerns are driving the surge of plant-milks in the market.

Manufacturing Process

The general formula for making plant-based milk is grinding the main ingredient (nut, bean, grain, etc.), then blending with water, flavours, vitamins, and minerals. Often, the manufacturing process involves some preprocessing treatments like dehulling, sprouting, and blanching. Dehulling involves breaking down of the thick and hard seed coats of the plant before soaking to facilitate hydration. Sprouting is the soaking of seeds in water for a period of time (depends on the kind of ingredient) to hydrate them for breaking their dormancy, which results in improved nutritional quality by inactivating anti-nutritional factors such as trypsin inhibitor and phytic acid, as well as increased levels of protein, fat, certain essential amino acids, B-group vitamins, etc. Furthermore, sprouting decreases the intensity of required heat treatment. Blanching inactivates certain enzymes to improve the flavour and nutritional value. Generally, manufacturing milk from plant can be processed in one of the 2 methods: wet and dry

Wet Processing

The plant based-raw material is soaked with a proper volume of water (depends on the plant material) to swell and soften the outer layer shell, thereby optimizing the extraction process. The extraction process involves the plant material being ground or milled with water for the split opening of the exterior hull, which results in a suspension.

Dry Processing

The plant based-raw material is dried with minimum water content, then milled into flours. The flours can be treated to yield different fraction of protein, starch, and fiber of the plant material, which can create a product with higher protein contents. Afterwards, the flours are mixed with water to form a paste. Because solids tend to settle down in the container, the content is incompletely transferred to the homogenizer. To ensure efficient processing, factors such as particle stiffness and feed size must be considered. Although dry processing has benefits such as decreased water wastage and energy consumption, and yield of product with higher protein content, it is less common due to handling problems such as dust and raw material wastage.

Afterward, the suspension/paste is filtered by either using filter cloth or by continuous process like centrifugation to remove insoluble or coarse particles. Then, ingredients like vitamins, minerals, oil, stabilizers, emulsifiers, flavours, coloring agents, salts, and preservatives are added. Next, the product undergoes homogenization, where a pressure in the range of 20-60 MPa is employed to improve the suspension stability. Followed by high temperature treatment like pasteurization, sterilization, or UHT to kill pathogenic microorganism and inactivate enzymes, the product is aseptically packaged for increased shelf life.

Fortification Regulation

Canada

Dairy milk is a dense source of essential nutrients, and there are standards in Canada which help determine its standard identity. Several essential components of milk, namely the macronutrient protein, and the micronutrients B12, vitamin D3, calcium, etc. are naturally abundant in milk. Plant-based milks, apart from soy, are generally low in protein and need to be fortified in order to meet the micronutrient composition of dairy milk.

In recognition of the growing demand of plant-based beverages and their use as a milk replacement by the public, Canadian fortification of plant-milk to meet nutritional requirements. In an Interim Marketing Authorization (IMA), Health Canada published an Interim Policy that authorized the fortification of plant milk beverages to be sustained: “The beverages must meet the compositional requirements for certain minerals (i.e. Vitamins A, D, and B12, riboflavin, calcium, and zinc), fats (i.e. total, saturated, and trans fats and linoleic acid, and protein (i.e. Plant based beverages must contain at least 2.5 g of a protein that is at least 75% the quality of casein per 100 mL; otherwise, they must be labeled as “not a source of protein”)”. Moreover, it is not permitted for animal-based milks or milk products to be added to fortified beverages. Additional vitamins and minerals can be added voluntarily by manufacturers to plant based beverages as optional ingredients (i.e., vitamins B6 and C, thiamine, niacin, folacin, pantothenic acid, phosphorus, potassium, and magnesium). However, they must be at the levels indicated in the IMA.

Other Countries

Despite the benefits, fortification of plant-based beverages with essential micronutrients is not standardized all over the world. Unlike Canada, The US government has not standardized plant based beverages, and so the brands vary in their nutritional compositions. In addition, the US government’s fortification regulations also allow for a lower level of Vitamin D than Canada’s.  

In Asian countries, such as India and Korea, where the concept of veganism is still new and the market is just opening up to plant-milks, fortifications are not mandated by the government and neither are they consistently considered by the manufacturers. However, there are fortification regulations around regularly consumed products; e.g. Indian grains are fortified to prevent micronutrient malnourishment.

With the growing market of plant milk globally, governments in other parts of the world would eventually need to follow the Canadian government in making regulations considering the nutritional requirements once they see a dominance of plant-based milk consumers over dairy milk consumers.

Exam Question

What is/are the benefit(s) of sprouting during the manufacturing process?

a) It yields higher amount of milk due to the plant-material growing in size and number.

b) It improves the nutritional quality by increasing the levels of protein, fat, certain essential amino acids, and some vitamins.

c) It removes the possible traces of lactose naturally found in the plant-materials.

d) It increases the creamy texture of plant-based milks.

Answer: b)

This question highlights the process of sprouting, which was not covered in class, but as it is related to the nutritional quality, we thought it would be a fun fact for everyone to know. We should also know from lesson 2 that lactose is a sugar that only occurs in animal milk, so c) cannot be the answer.