Pigments & flavours ppt

pigments and its processing effects also different types of flavors

1. PIGMENTS AND FLAVOURS PRESENTED To: PRESENTED BY: Dr. USHA SINGH ANJALI YADAV (Deptt. Of Food & Nutrition) 1906202006 Advance in Food Science Course no. (501)

2. CONTENT Pigments Chlorophyll Carotenoids Anthocyanin Anthoxanthin Betalins Turmeric and Saffron Synthetic colour Banned colour Flavours Taste

3. PIGMENTS A food pigment either synthetic or natural, which imparts colours to the food . The acceptance of a food depends to a large extent upon its attractive colour. Naturally present in the cells and tissues of plants. These are the most important factors, which are evaluated by the consumers while purchasing the foods. Pigments occurs in many forms consisting of liquids, powders, gels and pastes. Can be divided into two forms- 1. NATURAL PIGMENTS 2. SYNTHETIC PIGMENTS

4. NATURAL PIGMENTS CHLOROPHYLL: It is the green coloured water insoluble pigment involved in photosynthesis are present in many plants specially in green leafy vegetables. They also give the green colour to the “ skin of apples ”. Functional pigment of photosynthesis in green plants. Chlorophyll a : intense blue-green in colour Chlorophyll b : intense yellow green colour

5. EFFECT OF COOKING When green veges are put in boiling water, the green colour becomes brighter due to the translucency of plant tissues. Due to prolonged cooking process colour of green vegetables varies from bright green to olive green . When alkali (Sodium Bicarbonate) added it reacts with chlorophyll the phytyl and methyl groups are displaced and bright green water soluble “chloropyllin” formed. Freezing is the better retention of green colour in GLV’s due to elimination of plant acids by blanching prior to freezing.

6. CAROTENOIDS Carotenoid are also water insoluble pigment which is responsible for the – Yellow, Orange, c olour of fruits and vegetables widely distributed in nature. Carotenoids are extracted from Annatto, Saffron, Paprika, tomato etc. Some examples are: Yellow corn- cryptoxanthin Tomatoes - Lycopene Carrots - Beta carotene, Xanthophyll Red Capsicum- Beta Carotene

7. In plants carotenoids are present as α - carotene, β - carotene, γ - carotene, Xanthophyll and cryptoxanthin . Of all carotenoids β - carotene is valuable in the synthesis of Vitamin A. The colour of carotene is little affected by acid, alkali , and volume of water.

8. ANTHOCYANINS These are the red, blue , and violet water soluble compounds occuring in some fruits and vegetables. Eg. – Cherries, Red Apples , Blue Berries , Red grapes , Pomengranate are achieve their colour & appeal because of anthocyanin. These are contained in the vacuole of plant cells where their solubility in water makes them disperse freely.

9. As anthocyanin are water soluble cell sap pigment which can be leached from vegetable by the cooking water. Skin of radishes , sweet potatoes & leaves of red cabbage are due to anthocyanin . Addition of alkali gives the bluish green shade. When anthocyanin contact with iron, aluminium , tin and copper ions colour ranges from green to slate blue.

10. ANTHOXANTHINS These are creamy yellow, creamy white or yellow white water soluble compounds occuring in the cell sap of fruits& vegetables. They are colourless or white to yellow depending on pH. Pigments are generally whiter in an acid medium(lime juice or vinegar) or yellowed in an alkaline medium . eg: Cauliflower, Potato, Cabbage .

11. BETALINS Anthocyanin pigments are absent in some families which are replaced by compounds Betacyanins and B etaxanthins together known as betalins . Betalin are water soluble pigment which are present in Beet root ( beta vulgaris ). Acidic medium promotes reddish colour whereas alkaline pH brings out brownish blue . Beetroot extracts are widely permitted additives around the world.

12. TURMERIC and SAFFRON Turmeric is a root that has been used to impart colour and flavour to the food , produced by rhizomes of perennial herb, Curcuma longa . The colouring responsible for the oleoresin “ curcumin” , it is stable to heat but sensitive to alkali and light. Apart from colouring or flavour it has also medicinal property. Saffron is a spice derived from the flower of Crocus sativus , the crimson stigma and styles , called threads are collected and dried to be used mainly as seasoning & colouring agent ( rich golden yellow colour due to crocin) in food .

13. SYNTHETIC COLOURS/PIGMENT These are the artificial, non-natural colours manufactured by chemical reactions uses in industries (Foods, Pharmaceuticals) The synthetic dyestuff has many advantages over natural colours, that they tended to be much brighter, more stable, cheaper and a wide range of shades are available but have toxic properties also.

14. PERMITTED SYNTHETIC COLOURS COLOUR COMMON NAME Red Ponceau 4R Carmoisine Fast Red Amaranth Erythrosine Yellow Tartrazine Sunset Yellow FCF Blue Indigo Carmine Brilliant Blue FCF Green Fast Green S Green FCF

15. BANNED COLOURS According to Public Health(Preservatives etc., in Food) Regulations 1925 (amended 1926 and 1927) of the Ministry of Health, U.K., the following colouring matters are not permitted to be added to articles of food. Metallic colours : Compounds of any of the metals, antimony, arsenic, cadmium, chromium, copper, mercury, lead & zinc. Vegetable colouring matter : Gamboge . 3. Coal tar Colours : Picric acid, Victoria Yellow, Manchester Yellow, Aurantia , Aurine . In India, Acid Magenta II and Blue V.R.S ., which were used in Tomato Ketchup and Canned Peas are recently banned. Both are triphenylmethane dyes.

16. FLAVOURS Flavour is the sensory phenomenon which is a combination of all sensation of taste, odour or aroma, heat and cold, texture or “ mouthfeel ”. Flavour is the sensory impact determined mainly by the chemical senses of taste and smell. Appearance of food is important, but it is the flavour that ultimately determines its quality and acceptability. The taste of food can be characterised – sweet, sour, salty, bitter and the 5 th or latest one is umami. Many food items can be made consumable with the addition of flavours which increases the functional and economic value of food. Artifically chemically synthesised compounds or many food additives are used to impart flavour to food items.

17. TASTE The sensation of flavour perceived in the mouth and throat on contact with a substance. The basic tastes are: sweetness, bitterness, sourness, saltiness, umami( savoriness ).

18. SWEETNESS Sugars are used more to impart sweetness flavour to food. Fructose present in honey is the sweetest sugar followed by glucose and sucrose, lactose in milk. Natural sweet compounds are generally polyhydroxy compounds with a straight chain structure such as glucose , and the hexahydroxy cyclic alcohols mannitol & sorbitol.

19. BITTERNESS The bitter taste is perceived by many unpleasant, sharp or disagreeable compounds . Common bitter foods and beverages includes coffee, beer , bittermelon , citruspeel etc. These are due to alkaloids, glycosides other classes of organic compounds as well as inorganic salts. Naringin the bitter principle of grapefruit , Amygdalin a glycoside present in bitter almonds which is toxic, Horseradish contain alkaloid sinigrin which is harmful. Caffeine is bitter constituent of coffee& tea.

20. SOURNESS The sourness of food is due to the presence of organic acids of which citric, tartaric & malic are most common one. Sourness detect the acidity. Hydrogen ion is mainly responsible for the sour taste. Acetic acid produced by fermentation of alcohol is common in processed fruits. Ascorbic acid present in fruits & vegetables, Oxalic acid found in spinach are often used in food industry.

21. SALTINESS It is the most readily detected on the sides and tip of the tongue . Sodium chloride is the only salt that has a pure taste. Beside imparting flavour it is also an essential nutrient . Salt tends to decrease the sweetness of sugar to enhance the flavour required in confectionery products. Many salts have different tastes like some iodides & bromides are bitter while some salts of lead & beryllium are sweet .

22. UMAMI Umami ( Japanese term ) or “savory” flavourant more commonly called flavour enhancer which are largely based on amino acids and nucleotides . It is the 5 th taste receptor has been characterised and that for meaty taste for MSG(monosodium glutamate) when added to food called umami. L or Levorotatory form of MSG fits precisely at the binding site of receptors taste bud . Umami is the “delicious taste ” but also carries implication of meatiness, savoury , or broth-like.

23. REFERENCES B. Srilakshmi , Food Science 6 th edition page no: 187-88, 196-201. R.P . Srivastava , Sanjeev kumar Fruit &Vegetable Preservation 3 rd edition pg no: 39-45 Tom Coultate , Food- The chemistry of its component 6 th edition pg : 459 Mahtab S Krishnaswamy and G.N.V. Brahamam , Text book of human nutrition 3 rd edition pg : 433-36.