Milk and milk products are part of the everyday diet of many. Milk naturally contains essential nutrients like protein, calcium, potassium, phosphor, iodine and vitamins B2 and B12. In recent years, there has been increasing interest in beverages based on soy, coconut, oat, rice and nuts. In an article published in the International Dairy Journal, Chalupa-Krebzdak et al. (2018) analyse the nutrient composition of milk compared to these drinks.
Skimmed milk with 1%, 2%, whole milk with 3.25% fat and 17 plant-based drinks were compared in order to determine whether plant-based drinks provide a comparable amount of nutrients as milk and, consequently, can play a comparable role in the provision of nutrients.
Protein
In the study, milk was determined to contain an average of 3.15-3.37 grams of protein/100 ml. The amount of protein in plant-based drinks varies considerably. Soy drinks contain an average of between 2.5 and 3.16 grams of protein/100 ml. By contrast, rice drinks contain an average of 0.28 grams of protein/100 ml. Extra protein is added to some plant-based drinks.
Energy
The amount of energy in milk varies based on the fat content. The amount of energy in the study ranged from 34 kcal per 100 ml for skimmed or fat-free milk to 61 kcal per 100 ml for whole (3.25% fat) milk. As for plant-based drinks, the study found that the energy level ranged from 12 to 92 kcal per 100 ml. The researchers also noted that a large proportion of energy in plant-based drinks originates from carbohydrates and sugars and this leads to a relatively higher Glycemic Index (GI).
Glycemic Index
GI makes it possible to classify carbohydrate-containing foods based on the speed of carbohydrate digestion and absorption postprandial. This index reflects the direct effect of carbohydrate intake on blood glucose levels two hours after the meal. Since no GI information was available for the samples used in this study (Ciok & Dolna, 2006), the authors report the findings of Jeske et al., (2017), which show that plant-based drinks have higher GI values than milk. Milk had a GI of 46.93, while the GI of the plant-based drinks varied from 47.53 to 99.96 (Jeske et al, 2017). Low (<55 GI) and medium (56-69 GI) foods are recommended, especially for those who want to better regulate their blood sugar levels.
Fat
Although there was no data available for the total breakdown of saturated and unsaturated fats for all the plant-based drinks in this study, the authors noted that the available data indicated a trend towards less saturated and more polyunsaturated fats. Replacing saturated fatty acids with polyunsaturated fatty acids has a positive effect on the LDL cholesterol level in the blood.
Calcium
Calcium is needed for the maintenance of normal bones. The level of calcium varies greatly among plant-based drinks. The reason is that plant-based drinks are not always enriched with calcium. The researchers also point out that various bioactive components present in plants that can impact the absorption of nutrients must be taken into consideration. Phytic acid, for instance, which is found in many cereals and legumes, binds to a significant amount of calcium, causing reduced calcium bioavailability (Chalupa-Krebzdak et al, 2018).
Other nutrients
Milk naturally contains essential nutrients like protein, calcium, potassium, phosphor, iodine and vitamins B2 and B12. Plant-based drinks contain various nutrients not found in milk. These include soluble fibre in oat-based drinks and vitamin E in almond-based drinks. The researchers noted that the amount of nutrients per product varies.
Conclusion
Milk is a natural source of protein, calcium, potassium, phosphor, iodine and vitamin B2 and B12. The nutrient composition of plant-based drinks varies considerably. Nonetheless, the researchers have concluded that, from a nutritional perspective, plant-based drinks are not a suitable alternative to cow’s milk.
References
Chalupa-Krebzdak S., Long C. & Bohrer B. (2018). Nutrient density and nutritional value of milk and plant-based milk alternatives. International Dairy Journal. 87: 84 – 92.
Ciok J. & Dolna A. (2006). The role of glycemic index concept in carbohydrate metabolism. Przegl Lek. 63(5): 287-91.
Jeske S., Zannini E. & Arendt E. K. (2017). Evaluation of physicochemical and glycaemic properties of commercial plant-based milk substitutes. Plant Foods for Human Nutrition 72(1): 26–33.
Translated by: Nguyen Thi Lam Doan – Dept. Biochemistry and Food Biotechnology - FST - VNUA
Source: https://www.frieslandcampinainstitute.com/asia/dairy/milk/nutritional-differences-milk-plant-based-drinks