The goal of this clinical trial is to test effects of consuming probiotics in healthy adults. The main question it aims to answer is:

• Do consuming probiotics affect a healthy adult's ability to absorb amino acids from plant proteins?

Participants will

• Consume one dose of probiotic pills per day after meals for two weeks
• Consume one dose of plant-based plant protein beverage after an overnight fast and collection of one 5 ml fasting blood sample
• Undergo blood draw of 6 more 5 ml blood samples for the next 3 hours after consuming plant-based protein beverage

There is increasing evidence that the gut microbiota contributes to a range of immune, inflammatory, and metabolic responses. Numerous studies have shown that administrating probiotics - strains of bacteria that benefits intestinal function - confer benefits to the host's immune system. Except for soy protein, plant proteins are incomplete proteins lacking in one or more essential amino acids. The incomplete amino acid profile of most plant proteins is compounded by their lower rate of absorption as compared to animal protein. Hence, the investigators aim to investigate the administration of probiotics as a potential strategy to overcome compositional shortcomings of plant proteins by improving the gastrointestinal absorption of plant-based proteins.

The aim of Stage 1 is to formulate a plant-based protein beverage with optimized amino acid profile with consumer acceptance.

Stage 2 of this study will be to conduct a randomized, double-blind, placebo-controlled, crossover trial using the formulation developed in Stage 1, together with probiotics supplementation to evaluate the effect of probiotics on the absorption of amino acids from plant proteins.

The probiotics to be studied will be provided by the Asian Microbiome Library (AMILI) with the plant protein beverage to be developed within SIT. Findings from this mutually beneficial collaborative project with AMILI will pave the way to further understand the role of probiotics in human health, particularly its effect in nutrient absorption of plant protein.

Inclusion Criteria:

• Be willing and able to comply with study procedures and give written informed consent
• Self-reported to be healthy
• Within healthy BMI weight range (18.5-23kg/m2)

Exclusion Criteria:

• Any chronic medical condition
• Individuals who were treated for or diagnosed with a gastrointestinal, cardiac, respiratory, circulatory, musculoskeletal, metabolic, immune, autoimmune, haematological, neurological or endocrinological disorder
• Antibiotic use
• Prebiotics, probiotics, synbiotics, and/or digestive enzymes use
• Food allergy/intolerances/avoidances towards eggs, soya, peanuts, tree nuts, crustaceans, and gluten
• Smoking
• Alcohol consumption

Masked personnel will be unaware of which arm each participant is allocated to, and what type of probiotics have been assigned to each participant.