Hydrocolloids as Functional Food Ingredients for Gut Health
Condition: Healthy
Study type: Interventional

Summary: 
      Seaweeds are a natural source of nutrients, and dependent on the variety, are rich in dietary
      fibre, proteins, essential vitamins and minerals. However this resource is highly
      underexploited. Countries such as Japan, China, North and South Korea are large consumers of
      edible seaweed while exposure in Western countries is much lower and mainly as industrially
      extracted seaweed derivatives, a common additive in many food and healthcare products.
      Seaweeds have been associated with a number of human gut promoting health benefits such as
      decreasing faecal transit time through the gastrointestinal tract thus preventing
      constipation and resulting in a reduced exposure to harmful substances (decreasing colon
      cancer risk). These health benefits can be attributed to seaweeds high dietary fibre content.
      Interestingly, the food and healthcare industry already utilize seaweed-extracted fibre in
      the manufacturing process thus steering the way forward towards the development of novel
      functional food products. These seaweed-extracted fibres are high molecular weight
      polysaccharides known as hydrocolloids and are non-digestible by humans, hence classified as
      dietary fibre.

      Traditionally, seaweed derived polysaccharides (hydrocolloids) have been used to provide
      thickening and gelling functionality to food stuffs and other industrial applications however
      there is emerging evidence to show that lower molecular weight polysaccharides and
      oligosaccharides derived from these hydrocolloids can also act as a source of soluble fibre
      and may have prebiotic activity. Recent developments in Japan and Korea have lead to the
      commercial availability of products containing low molecular weight seaweed derived fibre.
      There is also some evidence for the beneficial effects of seaweed derived fibre in other key
      health areas such as cardiovascular health, cancer, diabetes and obesity. However, relatively
      little is known about the chemical, physio-chemical and fermentation characteristics of
      seaweed fibre in the human gut. Some hydrocolloids, notably guar gum (plant source), have
      also been employed for their health promoting properties in the areas of glucose tolerance
      and cholesterol lowering. However the use of hydrocolloids as functional food ingredients
      with health benefits for consumers has been rather limited and has focused more on uses in
      products for diabetics.

      It is particularly in the area of gut health that small and medium-sized enterprises (SMEs)
      involved in hydrocolloid production and processing, can enter the functional food ingredients
      market by using innovative processing technology. The total dietary fibre content of seaweed
      can be as high as 75% of the total dry weight and a high proportion of this is soluble. The
      fibre component essentially comprises the structural polysaccharides i.e. alginate and
      fucoidan in brown seaweeds, carrageenan, agar and porphyran in red seaweeds and ulvan in
      green seaweeds. As these fibres are primarily soluble, they form viscous gels as they pass
      through the gastrointestinal tract. Some of the fibre is fermented in the lower intestine but
      in general, soluble and insoluble seaweed fibre tends to pass through the gut without being
      digested. In its natural form as part of the seaweed plant, this fibre is typically high in
      molecular weight and passes through the gut too rapidly for the gut microflora to utilize it
      to any great extent. There is therefore a necessity to develop lower molecular weight forms
      that are more soluble and can be added at higher concentrations to food products without
      affecting the sensory properties of the product.

      The overall aim of the project is to realize an opportunity to produce low molecular weight
      polysaccharides (LMWP) from alginate- and agar-bearing seaweeds for applications in food &
      health. The two effective agar and alginate LMWPs, identified by in vitro studies, will be
      selected for assessment of prebiotic activity in a feeding trial in human volunteers (Ulster
      University) as part of an European Union (EU) study. The end points to be assessed will be
      stimulation of beneficial bacteria (bifidogenic effects), increased short chain fatty acid
      production, beneficial effects on stool formation, and improvements in gut barrier function.
      Additionally, benefits of the LMWPs towards blood glucose levels (short term and acute) will
      be assessed.
    


Intervention name(s): Agar H1CC2013; Agar H1CC2012; Maltodextrin
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): Following a 28-day washout one 250ml drink / day containing 8g of agar H1CC2013 as part of normal diet for 28 days; Following a 28-day washout one 250ml drink / day containing 8g of agar H1CC2012 as part of normal diet for 28 days; Following a 28-day washout one 250ml drink / day containing 8g of maltodextrin as part of normal diet for 28 days
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Basic Science
Keywords: Seaweed; Hydrocolloid; Functional Food; Dietary Fibre; Prebiotic; Low molecular weight polysaccharides; Alginate; Agar; HYFFI; Low molecular weight seaweed derived hydrocolloids as functional food ingredients; subjects