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Transcript

Hello, welcome back. This is the last week of this course. I hope you have gone through the contents of 1st, 2nd and 3rd week. And in the last 3 weeks we have studied Functional Foods, Nutraceuticals; their definition, sources, categorization, probiotics as a functional foods, and significance of functional foods, prevention of diseases and promotion of health. So let’s continue with this week. The first lecture. This is about functional foods with their health benefits. The functional components, they are distributed among the different plant foods. Like

• garlic, it contains sulphides and terpenes.
• green tea (phenolic acid, flavonoids and coumarins).
• soyabean, it contains phytates, phenolic acid, flavonoids and carotenoids.
• cereals contain phytates, phenolic acid, flavonoids.
• And citrus(phenolic acid, flavonoids, terpenes, carotenoids.
• And flax seeds ( phenolic acid, flavonoids and lignans)

Now lots of functional foods are claiming for the different health benefits. Let’s have a look about these health claims and their bio-active components part.

• The fortified margarines, they have plant sterols and plant stanol esters. And health benefit claim to reduce total and low density lipoprotein cholesterol and it is clinically proved. And recommended amount, how much should be taken. It is 1.3 gram per day. And if we talk about the regulatory status. This is Food and Drugs Administration approved health claim.
• Next is psyllium, a bio-active compound found in soluble fiber. It also reduce low density lipoprotein cholesterol. And the recommended dose is 1 gram per day. And this is also FDA approved. This is all are clinically proved.
• Next is soy. And the bio-active compound is protein. And it also claims the health benefit of the reduction of the LDL cholesterol. And recommended amount, how much we should take it. That is 25 gram per day. And this is also FDA approved.
• Then whole oat products which contain beta-glucan. They are also responsible for reducing the total and LDL cholesterol. And evidence proofs are very strong and clinically proved also. And the recommended dose is 3 gram per day. And this is also FDA approved.
• Then cranberry juice. And the bio-active compound present is proanthocyanidins. It reduces the urinary tract infections. Evidence are moderate, it is not clinically proved. Some trial has been done but it’s not clearly chose the proven benefit of the cranberry juice. And the recommended amount or recommended dose is 300 ml per day. So it will fall under the category of conventional food not the FDA approved one.
• Then another type of functional foods with the health benefits. Garlic, you know that garlic contain the organo-sulphur compounds, and health benefit is to reduce the LDL cholesterol.
• Similarly green tea contains catechins and health benefit is to reduce the risk of certain types of cancer. And this is the clinical trials but this is a survey based study. And the claims are weak to moderate. Not the very strong one. And it comes under the category of conventional foods.
• Then next functional food is spinach, kale and collard greens. And the bio-active compounds lutein and zeaxanthin. And it reduces the risk of age related muscular degeneration. And strength of evidence is weak to moderate. And the recommended amount is 6 grams per day. And it also comes under the category of conventional food or dietary supplements.
• Now tomato and processed tomato products. You know that tomato is a very rich source of lycopene. And one unique feature or unique parameter of lycopene is that it is the most active oxygen neutralizer, and also have a potent chemo-preventive activities. So lycopene is the most oxygen reducing bio-active compound. And it reduces the prostrate cancer. And the recommended doses are, we can have it daily. And it also comes under the category of conventional foods.
• Now another functional foods with the health benefits. That is animal based food, that is lamb, turkey, beef and dairy. And the bio-active compound is conjugated linoleic acid. Conjugated linoleic acid almost present in every food, but these dairy and animal based products, they have the higher quantities comparatively, and the foods related to the ruminants, they have comparatively the higher quantities. And the health benefit is to reduce breast cancer. And it has been the in-vivo and in-vitro studies has been conducted but the evidence are weak comparatively and it falls under the category of conventional foods.
• Then cruciferous vegetables like cabbage, cauliflower, broccoli. They have the glucosinolates, indoles. And they reduce risk of certain types of cancer. And evidences here are also weak. And the recommended amount; recommended doses, 3 or more servings per week. And it is conventional food.
• Then come to the fermented dairy products. We can say probiotics. They support the gastrointestinal health and boost immunity. And trials has been conducted in-vivo as well as in-vitro. And the clinical data is comparatively less. And the recommended dose is we can have it daily. And it comes under conventional or dietary supplements.

Now during manufacturing or during preparation of foods, we are applying many processing, like heat treatment, any kind of chopping and blanching, pasteurization, sterilization and other kind of treatment. So definitely these treatments when applied on the food during processing. They will either enhance the bio active compounds, or otherwise they will also affect the amounts or the quantity of the bio-active compounds adversely. One example I would like to quote here is that these carotenoids and some lipid soluble food components, they shows the increased amounts during processing due to the increased surface area; because this chopping and cutting, they definitely increase the surface area. And the heat treatment also even able to breakdown the carbohydrate complex, and in case the bio-availability.

But in some cases it will also affect quantity or the amount of the bio-active compounds adversely. Another factor that will affect the processing of functional component is length of post-harvest storage. Means how long the product has been stored after harvesting. Then thermal processing, that I have told you; that is, it may be steam blanching, it may be pasteurization, it may be sterilization, it may be canning, and many other thermal treatments are there. It has been found that 30-80% of the bio-active isothiocyanates, they lost during heat processing. The amount is quite high, that is 30-80%. And high temperature more than 100° inactivates the key enzyme, that is myrosinase. And in case of garlic, if the heating of garlic at 60°-100° temperature results in significant losses of its anti-inflammatory, anti-cancer, anti-microbial and anti-oxidant activities.

So temperature here adversely affected the bio-availability or the bio-active compounds of the garlic. Then bio-availability of carotenoids have been shown to improve with the processing with cutting and chopping. Then brewing of tea leaves. Either it may be black tea or green tea. It was found that during brewing process it released 69-85% of the bio-active flavonoids. Within 3-5 minutes they leach out or dissolve in the hot water. And these studies have been conducted by Kim in 2000 about the effect of processing on functional components.

So this is all about the different types of bio-active compounds, different types of functional foods and the processing effects, how the heat treatment, chopping, cutting and the other factors affect the quality of these bio-active compounds.

Thank You.