Optimising the sensorial and nutritional value of plant based milk alternatives.

Plant based milk alternative (PBMA) sales increased 33% between 2015 and 2017 (Wired, 2018) and
according to a recent Mintel report almost a quarter (23%) of Brits are using these products, with many
now choosing oat-based alternatives that are considered the most sustainable.
Sensory quality (aroma, taste & mouthfeel)
Oat milk-alternatives (OMAs) contain a variety of non-volatile tastants (sugars, polyphenolics) and volatile
aroma compounds (predominantly lipid and Maillard derived) that contribute to the product's aroma and
taste, and that are affected by thermal treatment. However, crucial to acceptability of OMAs is the extent
of astringency and mouthdrying. Oats contain aventhramides (phenolic alkaloids) and avenacosides
(saponins), which may contribute to astringency through binding to salivary proteins, thus reducing
lubrication. In addition, protein fortification leads to an alternative form of mouthdrying. Previous
research at the University of Reading has shown that fortification of beverages with whey protein causes
a drying sensation, building over repeated consumption, which correlates with the adhesion of protein to
the oral cavity (mucoadhesion) and is influenced by salivary flow. We propose that plant proteins may
also cause mucoadhesion and contribute to the mouth drying phenomena.
Nutritional quality
Bovine milk makes a substantial positive impact on the nutritional composition of western diets,
particularly through the provision of high quality protein with a complete amino acid profile, calcium in a
bioavailable form, and iodine. UoS have expertise in protein quality and mineral bioavailability.
Protein: In comparison to plant proteins, whey and casein are complete protein sources, which lead more
readily to muscle synthesis. Bovine milk contains 3.4% protein compared to just 0.3 to 1.0 % (w/v)
typically in commercial OMAs. Oat protein consists predominantly of globulin; characterised by its high
lysine content making it nutritionally superior to other cereal proteins. Calcium in bovine milk is more
bioavailable than from other sources because the lactose and calcium phosphopeptides in the milk
promote its absorption (as does vitamin D), whereas absorption is hindered in plant sources by
substances such as oxalates and phytates. These anti-nutritional compounds form insoluble complexes
reducing absorption. Beta-glucans: Oats are high in b-glucans, soluble fibre leading to slower absorption
of carbohydrates with benefits such as improved blood sugar control, lowering cholesterol, improved
immune function. These benefits need to be considered alongside the known positive effect that bovine
milk proteins have on blood pressure and on insulin stimulation in relation to type 2 diabetes.
Polyphenolics and Sterols: The aventhramides in oats have anti-inflammatory, antiatherosclerosis and
anticancer effects whilst the avenacosides have been noted for cholesterol lowering effects.