Functional Food and Food

Functionalisation Dr Dipak K Sarker

Biomaterials Research Group

School of Pharmacy and Biomolecular Sciences

University of Brighton

d.k.sarker@brighton.ac.uk

Brighton and Sussex Universities Food Network

Overview

Biological assembly of molecules in a complicated “soup”

• Use of foods as therapeutics

• Engineering of chemicals within “new” foods

Functional Food• The term Functional Foods was first introduced in Japan in the mid-

1980s and refers to processed foods containing ingredients that aid specific bodily functions

• Functional foods are foods that have a potentially positive effect on health beyond basic nutrition. Oatmeal for example, is a functional food because it contains natural soluble fibre that can help lower blood cholesterol

• Some foods are modified to have health benefits. Some functional foods are generated around a particular functional ingredient, for example foods containing pro-vitamins, probiotics, prebiotics, or plant stanols and sterols

• Functional foods are part of the list of products that people consume to increase their health status or contribute to reducing their disease burden

Functional foods. Position statement of the American Dietetic Association. Journal of the American Dietetic Association. 2009;109:735

Functional FoodExample Functional agent Benefit

Green tea Epigallocatechin-3- gallate, polyphenol

Free radical destroyer: use in anti-cancer and heart disease

Yogurt Metchnikoff’s “probiotic bacillus” – e.g. Lactobacillus rhamnosusLactobacillus acidophilus

Use in: colon microflora equilibrium, anti-diarrhoeal, reduction of peptic ulcer, ulcerative colitis, IBS; production of acidolin, vitamin K/B12/B9 - folate

Honey Quercetin, flavonoid pigment

Free radical destroyer: use in arterial and circulatory health, diabetes prophylaxis

Beer and wine

Resveratrol, polyphenol Free radical destroyer: use in anti-aging, anti-heart disease, anti-blood clot agent, anti-inflammatory, anti-cancer

Oats b-glucan, lipid binding polysaccharide

Use in: reduction in serum cholesterol/LDL (>10%) and vessel plaques

Soya Stanol ester EMEA approved. Use in: cholesterol uptake blocking, reduction in blood e.g. Benecol® spread

Functional Food• Nature teaches us a thing or two!

• Foods provide us with water, carbohydrate and glucose, protein, fats, minerals, vitamins/factors and water

• Foods are made of molecules (chemicals), water being one of them!

• A food chemical 

Vitamin C(ascorbic acid)Found in coloured fruit and vegetables used for tissue growth/repair and neutralising free radicals

Functional Food• Functional foods promote well-being in themselves. Soya, a mix of

protein, oil and intrinsic ingredients from the bean contains phyto-oestrogens (stanols) that reduce blood cholesterol/LDL and free fats, thereby reducing obesity, hyperlipidemia and athosclerosis

• Oats have after heating, a particular smearing texture; this is because they contain soluble and insoluble lubricating mucilages (glycoproteins) and polysaccharides (gums)

• They can: 1) bind water, increase stool volume and thus, aid bolus transit, reducing diverticulitis and bowel congestion and torsion but also 2) sequester excess lipids and fats (and heavy metals) allowing excretion without absorption and thus aid a low calorie diet and a lowering of risk with a fat-laden Western diet

• Broccoli, kale and beets - so-called "super foods" contain bright coloured pigments – betanin (reds), chlorophyll (greens), carotenoids (oranges), xanthophylls (yellows) and flavonoids and flavonols (pinks and violets). These compounds not only appear as pretty colours but also prevent free radicals that destroy tissue and cause cancer and fatty build-ups

Food Functionalisation

• We answer back to basic raw food (raw materials) with food improvements for our busy modern life!

• Food functionalisation, we copy functional foods and improve on them

Oil dispersible Vitamin C(ascorbyl palmitate)Added to fatty foods, such as biscuits and margarine to prevent them going rancidon storage

Another chemical

Food Functionalisation

 The secret is we build up in stages

1. Make something very tiny - assemblies of molecules

2. Add the assemblies to make a superstructure

3. Add the superstructures to give something that can be prodded, chewed, spread and poured with a texture that can be appreciated e.g. jams and confectionary

 

Without food technology we're “reduced to monotony”, with a perfunctory and a risky and poorly hygienic, parasite and germ-laden diet, which is incompatible with our busy lives, love of food and life-expectancy. The answer lies in harnessing natures secrets and adapting and reusing the materials that evolved over hundreds of millennia.

Jam: an assembly of water, pectin, seeds, fruit pieces, fruit acids and natural sugars

Food Functionalisation

• How do cranberries, citrus fruits and dry-cured salamis stay fresh? Because of the acids they contain (in order: sorbic, citric/ascorbic, propionic/lactic, respectively). We now use these acids to prolong shelf life in other commercial foods by retarding the growth of spoilage microbes and pathogens.

• How do you ensure you cover your salad leaves with simple oil and vinegar vinaigrette dressing? Add an emulsifier... ground mustard seeds, ground peppercorns or egg yolk. This means small oil droplets are evenly dispersed in the vinegar or lemon juice

Food Functionalisation

• How do you make foods such as, 1) soufflés, 2) mousses or 3) pannacotta, which are unique and contrived but ever so lovely? You need functionalising materials (polymers) such as:

• 1) egg white (ovalbumin) entwined with wheat and flour proteins (gliadins)

• 2) sugar-dehydrated ovalbumin and a-lactalbumin and b-lactoglobulin proteins from milk and

• 3) collagen derived gelatin (gelatine) or seaweed derived alginate for vegetarians, together with egg yolk lecithin to emulsify the fat globules in full fat cream.

An assembly of polymers and proteins gives a “jelly”(gel) that traps air, water or fat

Food Functionalisation

Ever had a “tannin furry tongue” on consumption of claret, grape skin or chewing a pip or green tea? That’s the polyphenols reacting with the protein of your tongue to cement and glue it up. A temporary situation. Food technologists now use tannin rich varieties of food, foods rich in natural tannins or refined natural tannins to improve foods.

Beer and champagne with long lasting froth (foam; head)... enhanced with hop acids and other polyphenols that glue together natural proteins in the product - give the bubble a mechanical resilience to soap in the glass rinse water or the lipid (natural soap) from your lips and lipstick

Let’s take a look at “simple” beer foam …

 

 

Beer foamBasic beer foam ingredients from malted and fermented barley and hops

 

 

Primary ingredient Functionalising agent

Hydrophobin proteins Iso-a-acids (hop acids)

Lipid transfer proteins (LTPs) Polyphenols e.g. catechin

Insoluble - hordein proteins Lipid fats

Hydrolysed hordein proteins Arabinoxylan gums

Elastic - protein Z b-glucan gum (beer viscosifier)

Lipid binding proteins (LBPs) Metals

Shokribousjein et al. (2011)

Beer foam stabilityGas in bubble

Beer liquid

bubble

Super-structured multiple layers

Hydrophobins

Hydrophobins are the surface attachment proteins produced by the fungus (yeast) Saccharomyces cerevisiae in brewing, they also trap carbon dioxide bubbles preserving drink “fizz.” Very important in lagers and beer froth. Beer is an excellent source of B vitamins (B2, B3, B5, B6, B9 and B12) produced as part of brewing (microbial synthesis)

Albumin protein Z

Hordeins

Arabinoxylans

Globular LTP

LBP

Trapped CO2b-glucans

Hop acid-metal complex

Polyphenol Interfering lipid

Shokribousjein et al. (2011); Hughes et al. (1999); Cooper et al. (2002); Linder (2009) - model of beer bubble surface and interstitial liquid

Foam stability models

Concentration of lipid (fat) in bubble surface

Mole

cula

r m

obili

ty,

D

Sarker et al. (1995a)

“Disruption of bubble surface”

Fracture

Sarker et al. (1995b)

“Joining of protein molecules on the bubble surface”

Unification

Concentration of polyphenol (catechin) in bubble surface

Mole

cula

r m

obili

ty,

D

Concentration of arabinoxylan in bubble surface

Surf

ace

ela

stic

ity,

E

Sarker et al. (1998)

“Rigidification of bubble surface”

Cementing

action

Conclusions• Natural and modified natural ingredients can be used to shape,

modify and preserve foods

• The same ingredients can be added in other combination to create new foods and create foods of superior quality, texture and taste

• Terms such as “nanotechnology”, the notion of molecular constructions, that in modern times alarm people have always been the building-blocks of all foods

• What we do is only a question of imagination - what the consumer wants and what the technologist is able to create

Acknowledgements

Instrumental in the work presented here:

• Dr David Clark, Bovina Mountain Consulting – New York

• Drs Yves Popineau and Monique Axelos, Institut National de la Recherche Agronomique – Nantes, France

• Dr Peter Wilde, Institute of Food Research – Norwich

References• Cooper, D.J. et al. (2002) Journal and Agricultural and Food Chemistry,

50: 7645-7650

• Hughes, P.S. et al. (1999) In: European Brewing Convention Symposium on Beer Foam Quality, 27: 129-138

• Linder, M.B. (2009) Current Opinion in Colloid and Interface Science, 14:

• Sarker, D.K. et al. (1995a) Colloids and Surfaces B: Biointerfaces, 3: 349-356

• Sarker, D.K. et al. (1995b) Journal and Agricultural and Food Chemistry, 43: 295-300

• Sarker, D.K. et al. (1998) Cereal Chemistry, 75: 493-499

• Shokribousjein, Z. et al. (2011) Cerevisia, 35: 85-101