With an increasing consumer trend towards the consumption of sustainable food resources and the complementary increase in vegan demands, plant proteins have been an epicenter for research and development over the past few years. With the advent of technology, plant-based meats and milks have found their way to a number of HoReCa (hotels, restaurants and catering industries) establishments around the globe. With fluid cow’s milk sales declining and an increasing demand for these plant-based alternatives, we are at a very critical conjecture of striking a balance between these two nutritionally wholesome and essential commodities.
The Milk Protein and Enzymes symposium started off with Mr. Hadi Eshpari, the host welcoming the attendees to ADSA 2021 Virtual Annual Meeting and briefly introduced himself along with the co-host Prof. Donald McMahon from Utah State University.
The very first speaker was Dr. MaryAnne Drake from North Carolina State University who would be talking about sensory properties of plant proteins in comparison with dairy proteins and opportunities for synergy. Dairy food trends were classified into two categories: first, conscious consumption with claims on sustainability like pasture-fed or glass bottles, and the second, alternative nutrition which focuses on higher proteins. The past few years have seen an increase in the consumption of plant-based alternatives owing to their claim of being a more sustainable alternative to dairy. The future of dairy now relies on positioning (adapting to the changing marketplace) and messaging (communicating to keep consumers receptive). Plant and dairy protein synergies have existed for years together in protein bars where soy and whey proteins have been traditionally used, the same for many ready-to-drink (RTD) beverages available in the marketplace. Opportunities for synergies rely on consumer requirements which have been leaning towards a higher protein content in their diet – but is the source of protein changing? A study conducted by her group in 2019 demonstrates that the three attributes that consumers prioritize the most are the flavor, type of proteins and the type of sweetener for bars and RTD beverages. Whey and milk proteins were conceptually preferred, whereas soy protein and caseins not being given a high priority. Another aspect that was important was for an ‘all-natural’ protein, with 20-29g of protein/serving with a natural sweetener. Plant protein and vegan were not classified as very important attributes or selection criterion. Another study in 2020 demonstrated flavor, contribution to health and pricing to be important with a sudden trend in consumer demand for sustainability. Consumers were mostly interested in price and variety as seen in a survey conducted for protein powders and were further divided into three clusters. Cluster 1 consumers displayed a rising trend in consumption of plant-based food, Cluster 2 consumers were flexible to trying out a new product whereas Cluster 3 consumers relied on word-of-mouth recommendations. Consumers demanded a good and complete source of protein, is a concern since it can only be assessed by qualitative consumers. Demographics also has an influence of choice of protein, with Gen X consumers being influenced by claims such as complete proteins, all-natural and non-GMO, whereas Gen Z consumers are more concerned about sustainability. Plant proteins are considered to be superior to dairy proteins in sustainability, health, ethics and digestibility whereas the latter precedes in terms of taste and satiety.
Dr. Milena Corredig from Aarhus University then presented an exciting front on processing dairy proteins with plant proteins. Since the latter is often correlated to sustainability, she initiated her talk with the FAO definition of a sustainable diet – one with low environmental impacts, accessible, protective and respectful of biodiversity and ecosystems, nutritionally adequate and economical, to state a few. With the Danish government introducing sustainability and plant-based products as a part of dietary guidelines along with consumption of 100g of cooked legumes every day – this brings about a huge transgression, shifting 50% of the traditional protein intake to plant protein alternatives. Affordability, safety and personalization need to be considered while changing consumption habits. Legumes, owing to their low acreage requirements and ability to capture nitrogen, are one of the biggest drivers of sustainability. Blending ingredients has been practiced for decades and hence providing a series of products from an alternative ingredient should not be an arduous task! With most individuals having an underlying affinity for dairy, it can be used as a platform for functionality, taste and nutritional adequacy. Strengths, opportunities and challenges need to be thoroughly examined to present opportunities to innovate. Varietal differences for legumes need to be addressed with respect to growth conditions, application areas and nutrient composition and can often present a challenge for incorporation in a commercial product. Extraction of plant-proteins can be extensive and uneconomical owing to their complex matrices and extraction methods determine product characteristics. Dry milling and wet milling methods affect overall composition, functionality and end application of these protein isolates, concentrates and flours. As a concluding note, Dr. Corredig discussed the top-down and bottom-up approaches for formulating a product with an optimal blend of protein with nutritional and technological functionality.
After an informative talk on processing, Mai Nygaard, Director of Fermentation (plant-based) at Chr Hansen gave an enriching talk on modulating taste and texture in plant-based yogurts or ‘vegurts.’ Grains (oat, quinoa, millet), nuts (coconut, almonds) and legumes (soy, pea and lupine) are gaining popularity for their applications in numerous plant-based alternatives. Coconut and soy, owing to their neural taste have found wide acceptability among the masses. Fermentation cultures play a central role in delivering taste, texture, health along with sustainability and quality of products. Reducing of food waste and shelf-life extensibility have become important selection criterions. Protein network in milk in presence of lactic acid as a result of fermentation are responsible for the characteristic texture, creaminess, viscosity of yogurt. Flavor is attributed to by-products of fermentation. Plant-based alternatives have a number of unknown factors altering end product characteristics and hence posing a new hurdle. Factors affecting quality of the cultured plant products depend on plant source, type and level of fat, presence of fermentable carbohydrates, stabilizer and the quality of water. Cultures are similar to that of dairy products but there is scope to tap into a set of unexplored species compatible with these alternatives. Pre-processing, anti-nutrients and presence of fermentable solids (often externally added) are critical parameters to check in maintaining homogeneity in the end product. Flavors can be adapted from dairy which includes aldehyde, diacetyl and acetaldehyde which may or may not show up in sensory assessments. Off-flavors like pea-notes, bitterness need to be addressed by selection of strains that can modify these undesirable flavors. Exopolysaccharides generated during fermentation can strongly contribute towards creaminess and yield strength of the gel thus obtained. She then walked us through the product portfolio at Chr Hansen keeping texture and intensity as key parameters with supporting data for a coconut and pea protein blend.
The final speaker for the day was Dr. Simon Loveday from AgResearch who discussed a very important aspect – if dairy factories could adapt to this trend of plant proteins. Since dairy production is seasonal, there have been concerns over the idleness during off-seasonal periods and increasing demand for plant-based products. Can these factories be used to process plant proteins during these idle times? The first following question was about the selection of the protein source– oilseeds, legumes or cereals? Pre-processing conditions are variable with the inherent protein chemistry of each raw material. He discussed the manufacture of soybean proteins in detail with emphasis on each stage including pre-cleaning, dehulling, sieving, aspiration, cleaning, sorting, scouring and flaking – wonder if all of these steps can be achieved in a dairy factory? Oil separation is the very next step with solvent extraction using hexane. Extraction hardware to deodorize this oil is problematic and often economically expensive for a dairy factory. This defatted mill is treated with acid and water, then treated with alkaline solution with pH control and subsequent protein extraction steps and purification using isoelectric precipitation and spray drying. Comparing to an acid casein extraction process, some of these hardware’s could be incorporated for extracting plant-proteins with a number of accessories. He then arrives at a conclusion that protein concentration by isoelectric precipitation and ultrafiltration, drying and packaging could be achieved in a dairy factory, but pre-processing, conditioning, defatting, oil-refining and extraction had almost little or no feasibility. An alternate manufacturing process along with solubility of proteins, hemp proteins and future scopes were then discussed. Since Dr. Loveday could not join us live for the symposia, he was kind enough to share his contact information to address any questions from the audience.
The session ended with a Q&A session from the attendees who addressed concerns of allergenicity, peptides formed during the digestion, government recommendations on this dietary push, and the behavior of bacterial consortia in a plant-based media compared to the traditional dairy substrates.
Rahul Venkatram is a first-year master’s student in the Department of Food Science and Technology at The Ohio State University advised by Dr. Rafael Jimenez-Flores. We currently work on exploring novel processes to reduce the antigenicity of dairy proteins and enhance the versatility of dairy products.