Effects of the Consumption of SEAweed Biomass Versus PROtein Isolates on Postprandial Satiety and Metabolism

Overview

There is a need to identify alternative sources of protein that can be introduced into diets to effectively meet the protein requirements of the population. Seaweed presents a potential source of sustainable, alternative protein. In order to determine their utility in future foods, in this study we will undertake an acute postprandial trial to explore whether a macroalgae (porphyra) and a microalgae (chlorella) protein isolates are more beneficial for acute metabolic health as compared to their respective whole biomasses. In particular, we will compare the effects of whole biomasses and their protein isolates on acute glucose homeostasis, amino acid availability as well as on satiety and gut hormones.

Seaweed presents a potential source of sustainable, alternative protein. Broadly categorised into macroalgae and microalgae, macroalgae including those of the genus Porphyra are traditionally known as nori or laver and is a common ingredient in several Asian dishes such as soups and sushi. Porphyra is rich in protein, micronutrients and dietary fibre and the equivalent variety in New Zealand is a red macroalgae known as Karengo. A prominent genus of microalgae is Chlorella, which is a green microalgae also rich in protein and currently used mainly in dietary supplements. The interest in seaweed as an ingredient incorporated into meals, food products and dietary supplements has been growing due to their macronutrient composition and bioactive substances with studied health benefits including improvements in glucose homeostasis, appetite and anti-hypertensive and hypocholesterolemic properties. However, controlled human studies comparing specific macroalgae and microalgae, particularly for their potential to be used as a source of alternative protein, has been limited. Therefore, the present study aims to compare macroalgae (Porphyra) biomass and its protein isolates versus microalgae (Chlorella) biomass and its protein isolates on postprandial satiety and nutrient metabolism in healthy adult Chinese males by adding these as ingredients to a noodle soup dish. We specifically aim to explore whether the protein isolates are superior to the respective whole biomasses in terms of glucose homeostasis, amino acid availability as well as in terms of satiety and gut hormones. Results from this study will be used towards future food applications to enhance the potential of the use of seaweed as a sustainable and nutritious source of alternative proteins.