Scrigroup - Documente si articole

Username / Parola inexistente      

Home Documente Upload Resurse Alte limbi doc  

CATEGORII DOCUMENTE





BulgaraCeha slovacaCroataEnglezaEstonaFinlandezaFranceza
GermanaItalianaLetonaLituanianaMaghiaraOlandezaPoloneza
SarbaSlovenaSpaniolaSuedezaTurcaUcraineana

AdministrationAnimalsArtBiologyBooksBotanicsBusinessCars
ChemistryComputersComunicationsConstructionEcologyEconomyEducationElectronics
EngineeringEntertainmentFinancialFishingGamesGeographyGrammarHealth
HistoryHuman-resourcesLegislationLiteratureManagementsManualsMarketingMathematic
MedicinesMovieMusicNutritionPersonalitiesPhysicPoliticalPsychology
RecipesSociologySoftwareSportsTechnicalTourismVarious

Dill Production - Compounds influencing flavour

nutrition

+ Font mai mare | - Font mai mic







DOCUMENTE SIMILARE

Trimite pe Messenger
Poppy - Cultivation and uses
Garlic - Processing, properties and toxicity
Capsicum, chillies, paprika, bird’s eye chilli - Production, properties and toxicity
Tamarind Production and Sources
Black pepper - Cultivars and varieties: quality issues, Industrial processing
Onion - influences on flavour and Production
All About Protein - Sources of Protein, Biological Value
Clove - Production and uses in food processing
Saffron - Production and uses
Kokam and cambodge - Functional properties

Dill



1       Introduction

Dill (Anethum graveloens Linn.) is an annual aromatic branched herb known for culinary use since ancient times. It is a native of south-east Europe and is cultivated commercially in  most  parts  of  Europe,  particularly  The  Netherlands,  Hungary,  Germany,  Romania, South  Russia,  Bulgaria  and  on  a  lesser  scale  in  France,  Sweden,  Belgium,  Poland, Greece, Spain, UK, Turkey and the United States of America. A variant called east Indian dill  or  Sowa  (Anethum  graveloens  var  sowa  Roxb.  ex,  Flem.)  occurs  in  India  and  is cultivated  for  its  foliage  as  a  cold  weather  crop  throughout  the  Indian  sub-continent, Malaysian archipelago and Japan. The earliest reference to use of dill seed in medicine goes back to ‘Charak Samhita (700 BC), an ancient renowned medical treatise on Indian medicinal plants.

Dill  foliage,  fruits  and  their  volatile  oil  are  used  extensively  for  culinary  and medicinal  purposes.  The  fresh  aromatic  leaves  are  used  in  flavouring  of  soups, sausages, curries, gravies, salad, marinades and pickles; the leafy stems and tops are used  in  flavouring  vinegar,  pickled  cucumber  and  fermented  cabbages,  whereas  the seed  is used  for flavouring  meat.  In Malaysia  and  Indonesia,  the  leaves are  steamed with rice whereas fruits are used in flavouring native confectionery. Balkan countries use dill in flavouring yogurt, sour cream and wine. In Sweden, bread is flavoured with dill seed. Dill fruit faintly resembles caraway in odour but has a less sharp taste. It is a popular  condiment  in  Asian  countries  and  is  used  in  seasoning  several  types  of processed meat. The leaf oil has largely replaced the use of the fresh herb in the food industry in Europe.

The International Trade Centre (Anon. 1991) has brought out a material survey of four west  European  countries  (France,  UK,  The  Netherlands  and  Germany)  estimating  an overall demand of freeze-dry herb to be less than 300 tonnes per annum. France produces a small quantity and imports it from Egypt, Israel, The Netherlands and Morocco. The Netherlands and Germany are larger producers and import a part of their demand from Hungary. The USA is said to import between 70 and 100 kg of herb oil annually, largely from Hungary. India exports 500 to 800 tonnes of seed annually to west Asian countries


and  a  small  quantity  of  dill  seed  oil  to  western  Europe.  Varshney  (2000)  has  reported world production of dill weed oil as 80 tonnes and that of dill seed oil as 70 tonnes; the seed oil is produced mainly in India, Russia and Poland.

Dill is characterized by long dissected leaves and compound radiating umbels. It grows to between 1 and 1.2 m in height  under cultivation.  Dill is an annual glabrous, long-day plant with long fusiform (10–15 cm) tap root with few secondary rootlets. The stem is erect, dull-green, glaucous, cylindrical, fistular with longitudinal light-green streaks, up to 1.5 cm thick around the base. It is subdichotomously branched, usually above the basal few nodes. Leaves are decompound, tripinnati-partite with ultimate segment 5–15 (   20) mm long and

1–1.5 mm wide. Flowers are small, bisexual, more in outer unbellules (30–40) than inner ones (15–20), and opens centripetally. The fruit is oblong, slightly plano-convex in shape, dorsally compressed, 3–4 mm long and 1.5–3.0 mm broad, glabrous, with three prominent longitudinal  ridges,  developed  into  thin  broad  wings,  0.25–0.5 mm  wide.  Dill  flowers  in June–August and fruiting takes place in August–October in Europe, while it is February– March and March–April respectively in India.

In the Sowa plant, the fruits are longer, 3–5(   5.5)         1.5–2.5 (   3) mm in dimension, with three longitudinal ridges on the dorsal side more pronounced than the (European) dill.  The  carpophore  holds  two  mericarps  more  firmly  and  consequently  these  remain joined together in the fruit for a longer time. The vittae has irregular marginal walls in contrast  to  straight  walls  in  the  dill.  It  has  a  number  of  local  races  like  Vizak  Sowa, Variyali Sowa and Ghoda Sowa distinguished by the oil composition of their fruits (Shah and Quadri, 1994; Randhawa and Kaur, 1995).

2       Production

Dill  is  grown  as  an  irrigated  annual  crop  both  in  temperate  and  tropical  regions  up  to

1000 m (m.s.l.). The crop remains in the field for 125 to 180 days. In India, sowing is staggered  at  a  fortnight’s  interval  (Oct–mid-December)  to  obtain  fresh  foliage  crop, marketed  throughout  the  winter  season.  A  large  number  of  varieties  are  known  in cultivation (Randhawa and Kaur, 1995). Dill prefers light sandy to loamy well drained fertile soils, slightly acidic  to neutral  in reaction;  the pH extends to 8.5 in sub-tropical parts  of  India.  It  prefers  warm  sunny  weather,  particularly  cool  moist  climate  favours vegetative  growth  and  warm,  drier  and  sunny  conditions  are  needed  for  luxuriant flowering and fruiting to ensure a high crop yield.

The  seed  is  sown  directly  during  the  spring  season  (February–March)  in  temperate climate and October in tropical conditions. Seed rate is 5 to 10 kg per hectare depending on the method of sowing, viz. drilling in rows or broadcast; usually it is sown in rows, 1.5 to 2.0 cm deep at 30 to 60 cm apart and spacing at 45  20 cm is found to produce high seed  yield  in  India  (Gupta,  1976).  Germination  commences  after  a  week  in  tropical regions   and   may   take   two   weeks   in   warm   temperate   conditions.   Pre-emergence application  of  herbicide  like  Prometryne  (50%)  at  1.0 kg  per  hectare  is  recommended

(Timoshenko, 1970). The plants are thinned when 7 to 10 cm tall at 15 to 20 cm apart in the  rows.  The  crop  remains  40  to  67  days  in  vegetative  stage  (after  germination)  and flowering/fruiting continues for the next 85 to 90 days. Powdery mildew (Erysiphae spp.) sometimes  attack  the crop at flowering, occasionally causing severe damage for which spraying of Bordeaux mixture  three to four times at weekly intervals  is recommended. Similarly,  aphids  (Myzus  spp)  suck  flowering  axils  causing  loss  in  growth  vigour  and weekly spraying of Melathione (0.2%) in water controls the infestation.




The crop responds favourably to use of inorganic fertilizers depending on the nutrient status of the soil. Atanasov et al. (1976) observed that application of 70 kg per hectare each of N, P2O5  and K2O produced maximum herbage yield and most economic oil yield in  Bulgaria.  In  India  where  soils are  rich in  potash,  60 kg of  N and  45 kg of P2O5  per hectare  produced  maximum  seed  yield  (Gupta,  1982).  Usually,  five  to  eight  light irrigations are given to the seed crop. Two rounds of weeding cum hoeing given between

30 and  40 days and  60 and  70 days suffice  to  control weeds; later  growth  of the  crop covers the field and smothers weeds.

The  herb  oil  is  a  colourless  to  brownish-yellow  mobile  liquid.  The  fresh  herb  at vegetative stage contains 0.60% of oil, which progressively increases with growth and is

0.78–0.99% at flowering, rises to 1.281.91% at milky-wax seed ripening and 1.9–2.84% in the herb when the seed is nearing maturity. For herb oil, the crop is harvested when it is between maximum flowering to beginning of fruit formation stage as oil content in the leaves is high and the oil has a lower amount of oxygenated compounds. In Germany and The  Netherlands,  the  entire  over-ground  crop  is  harvested  at  blooming  stage  (with  no seeds) whereas milky-wax to mid-ripe fruiting  stage is preferred  for obtaining herb oil

(dill weed oil) in Hungary and USA. As a matter of fact, the relative quantity of fruits present in the harvested material and their state of ripening determine the oil content and flavour of the oil produced on distillation. On average 2.5 to 3.0 tonnes of fresh herb per hectare is produced when the crop is harvested at maximum flowering stage, which on distillation give 18 to 20 kg of herb oil, containing up to 30% carvone. Harvesting at later stages increased oil yield and its carvone content progressively.

In the seed crop, the terminal  umbels are hand-picked  when the fruit begins to turn yellowish-brown in colour; these come to maturity 40 days early. The rest of the crop is cut  from  the  base  later  when tertiary umbels  begin to  turn  brownish; delay  may  cause seed shattering leading  to crop loss. The  harvested  crop is transported  to the  threshing floor  where  it  is  dried  in  a  thin  layer  for  one  or  two  days  before  carrying  out  light threshing  to  separate  the  fruits.  It  is  found  that  the  milky-waxy  fruit  maturity  stage contains  maximum  seed  oil  (Zlatev,  1976);  the  carvone  and  dihydrocarvone  contents accumulated rapidly in the later part of fruit maturity. The seed yield ranges from 700 to

800 kg per hectare and shade dried seed contains 3–4% oil; the seed yield in east Indian dill (Sowa) is higher (1 tonne per hectare).

The wilted dried plants show a decrease in carvone content over the fresh herb at every stage of growth until flowering, but this trend is reversed in fruiting herb as wilted, dried and stored material showed an increase in carvone content in the oil. As a matter of fact, the  dried  herb  produces  oil  emitting  poor  intensity  of  odour.  The  mature  stored  seeds yield a higher quantity of carvone because some of the terpines in the seed are lost during storage; this could be protected by storing seed in gunny bags, lined with polythene in a dry cool place.

The essential oil of herb as well as seed crop is obtained through hydrodistillation or steam  distillation  and  complete  exhaustion  of  the  produce  takes  4.0  and  2.5  hours respectively  for  herb  crop  and  8  to  10  hours  for  seed  crop;  the  seed  are  crushed  into powder  to  facilitate  easy  extraction  of  the  oil.  During  the  first  one  or  two  hours,  the distilled  oil  has  high  d-carvone  content  and  the  broad  ratio  between  carvone  and limoanene is 80(88) : 12(19); because carvone is more easily soluble in water and being higher boiling fraction, it is distilled easily. This trend declines at a later stage. The wilted

(herb) material should be distilled within 72 hours.


3       Chemical composition Lawrence (1980) analysed dill herb using IR as a method of characterization of individual constituents by preperative GC and column chromatographic fractions. He reported the oil  to  contain                     -pinene  (0.9%),                          -pinene  (0.1%),  myrcene  (0.4%),         -phellandrene

(30.2%),   limonene   (22.5%),          -phellandrene   (3.8%),   p-cymene   (1.0%),   terpinolene

(0.1%), -p-dimenthylstyrene (0.1%), 3,9-epoxy-p-menthlene (5.6%), cis-p-mentha-2,8- dien-lol   (0.1%),   transdihydrocarvone   (0.5%),   cis-dihydrocarvone   (1.2%),   carvone

(31.6%),  di-hydrocarveol  (0.1%),  cis-carvyl  acetate  (0.1%),  trans-carveol  (0.1%),  cis- carvyl   acetate   (0.1%),   trans-carveol   (0.1%),   dihydrolimonene-10-ol   (0.1%), dihydrolimenon   e10-yhexanoate   (0.1%),   p-mentha-l,   3-dien-10-yl-hexanoate   (0.1%) and  p-mentha-1(7), 2-dien-10-yl  butyrate (0.1%) besides  a host of other compounds in traces.




Lawrence (1981) has reproduced chemical composition of seed oil obtained through solvent extraction by Kodam at Leiden University (doctorate dissertation). It was found to  contain  limonene  (44.0%),  d-p,  dimethylstyrene  (0.2%),  transhydrocarvone  (0.4%), cis-dihydrocarvone (2.1%), neodihydrocarveol (0.2%), carvone (51.5%), dihydrocarveol

(0.1%),  isodihydrocarveol  (0.4%),  trananethole  (0.1%),  trancarveol  (0.1%)  and  cis- carveol  (0.2%)  besides  many  other  compounds  in  traces.  An  interesting  feature  of growing  dill  is  that  after  successive  generations,  the  European  dill  develops  higher oxygenated compounds in the oil, which includes a small quantity of dillapiole. It was found to contain up to 3.0% of dillapiole (Baslas et al., 1971) when grown under tropical climate. Gupta (1982) explained this as being due to more sunlight hours combined with solar intensity in the tropics.

4       Compounds influencing flavour

The principal constituents of the herb oil are phellandrene and limonene whereas ketone

(calc.  as  carvone)  in  the  oil  increases  from  12%  (vegetative  stage)  to  22%  (maximum bloom) and rises to 35% at the milky-wax stage, when its herb character predominates. In trade,  the  oils  containing  20%  or less  carvone  have  been  found to  be of  finest  flavour

(Guenther, 1950). The herb oil has a powerful sweet-spicy, peppery and aromatic odour, reminiscent of spearmint oil with a sweet nutmeg-like undertone. The taste is warm and slightly burning, but pleasant and not pungent.

For  flavouring  purposes,  the  herb  oil  with  low  ketones  (carvone)  is  preferred.  The typical flavour of the oil is due to                                   -phellandrene (terpine) as the oil resembles the fresh herb in aroma. Haupalehti  (1986) determined  that            -phellandrene,  limonene,  myrsticin and dill furan were the most significant contributors of dill herb aroma. Later, Blank et al.

(1991) determined that the aroma of dill herb was directly related to concentration of five components   namely   dill-furan,                                 -phellandrene,   limonene,   myrsticin   and   p-mentha dienbutyrate.

The seed oil is very mobile, light yellow to pale-yellow in colour, becoming dark on ageing; and its taste is less sharp than caraway oil. Its aroma is warm and spicy, slightly burning but pleasant and powerfully aromatic sweet. The oil contains large quantities of carvone  (40–60%)  which  is  its  principal  flavour  constituent.  There  is  no  difference  in odour value between dill and Sowa seed oils. The aroma of dill seed oil was characterized by  carvone  but  4-vinyl-2-methoxyphenol  (which  gives  it  a  spicy  meat-like  note),  4- hydroxy-3-methyl-6(l-methylethyl) cyclohexenlone (responsible for dill like sweet note) and dill furan contribute to its characteristic flavour.


5       Functional properties and toxicity

The leaves are rich in minerals, mainly calcium, phosphorous and iron; they contain nine amino acids as well as flavanoids. However, both these oils have anti-bacterial property and are known to protect prepared food from contamination during storage.

In traditional  medicine  dill  fruit has carminative,  aromatic  stimulant,  stomachic and diuretic properties. The emulsion of seed oil in water (dill water) is useful in relieving flatulence, colic pain, vomiting and is a household remedy to correct gastric disorders in children.  The  dill  fruit  contains  petroselinic  acid  triglyceride,    -sitosterol,  glucoside, coumarins and flavanoids as well as large quantities of fats and proteins. It is also used in veterinary medicine.

The  oil  of  east  Indian  dill  (Sowa)  has  an  additional  component  called  dillapiole

(C12H14O4, molecular weight 222.23) in high proportion (20%) and, compared to dill, has lower carvone content (30–45%). The dillapiole is toxic when taken in large doses. But being heavier than water with high boiling point (285sC), it is easily separated through fractional   distillation.   The   oil   free   of   dillapiole   approaches   physical   constants   of European dill (seed) oil (Shah et al., 1972) and being a cheaper source, is employed in production of gripe water. The dillapiole is a viscid colourless substance and is found to have a synergic action on pyrethrins (used in insecticides), making it more effective over synthetic synergics like piperonyl butaoxide.

6       Quality indices and standards

The  presence  of  a  minimum  of  5.0%  3,9,epoxy-p-menthene  in  dill  herb  oil  is  a  good indicator  of  its  purity.  There  is  no  commercial  source  of  this  compound  available  to enable  reconstitution  of  the  oil.  Lawrence  (1981)  has  opined  that  examination  of  the percentage  ratio  of,    -phellandrene  to  limonene  to -phellandrene  is  another  test  for quality determination; the acceptable ratio was found to be 20:25:3 in dill herb oil.

Dill herb oil is easily differentiated from caraway oil as carvone content in the latter ranges from 47.3% to 59.5%, while in dill oil it is 27.2 to 53.3%. Further, the                     -pinene and   -phellandrene in the caraway oil is very meagre (traces to 0.1%) whereas these are between 0.1 to 0.2% and 1.0–2.3% respectively in dill herb oil.

The east Indian dill seed (Sowa) oil contains large quantity of dillapiole (20%) and the oil  has  three  flavanoids,  viz.  quercetin,  kaempterol  and  isorhamnetin,  which  produce distinct spots on TLC (Shah and Quadri, 1994). The presence of high carvecrol is usually an indicator of an aged, partially oxydised, seed oil. The LD50  of dill seed oil is 300 mg per kg body weight (tested on mice).



According  to  the  British  Pharmaceutical  Codex  (Anon.  1963),  the  dill  fruits  should contain not less than 2.5% (volume by weight) of volatile oil and not more than 3.0% of acid  soluble ash. The commercial  powdered dill  should be ground fine enough to pass through a mesh of 54 screen. It should contain not less than 43.0% (w/w) and not more than 63% (w/w) of carvone.

The physical constants of dill are (Anon., 1964):

   specific gravity (25sC) 0.890–0.915 (temp. correction factor 0.00056 per sC)

   optical rotation +70s to +82s

   refractive index (20sC ) 1.4830s–1.490s

   carvone content 42 to 60 (by neutral sulphide method)

   soluble in two or more volumes of 80% alcohol (occasionally) with slight opalescence.


As  a  rule,  organoleptic  evaluation  of  the  oil  can  easily  identify  variations  introduced through addition or substitution of any flavour compounds in the oil. The specification of oil of east Indian dill seed (Sowa) is (Anon. 1992):

   specific gravity (27sC) 0.9360–0.9800

   optical rotation +50s to 65s

   refractive index (20sC) 1.426–1.495

   ester value before acetylation 35–42

   ester value after acelylation 50 to 65

   total ketone (calc. as carvones) min. 35%

   soluble in 0.5 and more vols of 90% alcohol.

7       References

ANON.  (1963)  British  Pharmaceutical  Codex.  The  Pharmaceutical  Press,  London,  pp.

262–3.

ANON. (1964) Revised  and New Standard of the Essential Oils Association of the USA. EOA: 158 (dill seed European)

ANON. (1991) Dry Culinary Herbs an overview of selected western European markets. International Trade Center (ITC), Geneva, p. 5.

ANON.  (1992)  Oil  of  dill  seed  (Sowa)  specification.  Bureau  of  Indian  standards  (BIS) Manak Bhavan, New Delhi, IS:3147, 1–3.

ATANASOV, Z.H., ZLATEV, S, ZLATEV, M.  and STOYANOV, M. (1976) The effect of mineral fertilization on the yield and essential oil content of dill. Restoniv dni Nauki, 13(1),

138–43 (Hort. Abstr.) 47, 765.

BASLAS, R.K.,  GUPTA, R.  and  BASLAS, K.K.  (1971)  Chemical  examination  of  essential  oil from plants of genus Anethum (Umbelliferae): Oil of seed of Anethum graveolons.

(Pt I) Flavour Ind. 2(4), 241–5.

BLANK, I. and GROSCH, W. (1991) Evaluation of potent odorants in dill seed and dill herb

Anethum graveolons L.) by aroma extract dilution analysis. J. Food Sci. 56(1), 63–7. GUENTHER, E. (1950) The Essential Oils. Van Nostrand Co, New York, pp. 619–34. GUPTA, R. (1976) Studies in cultivation and improvement of dill (Anethum graveolons L.)

in India (Part III) Indian Perfum, 20(A&B),   85–9.

GUPTA, R. (1982) Studies in cultivation and improvement of dill (Anethum graveolons) in India.  In Cultivation  and  Utilization  of  Aromatic  Plants, Eds. C.K. Atal  and  B.M. Kapur, Regional Research Laboratory, Jammu, pp. 545–8.

HAUPALEHTI, R. (1986) Gas chromatographic and sensory analysis in the evaluation of dill herb (Anethum graveolons L.) Lebensmitt. Wiss. Technol., 19, 27–30.

LAWRENCE, B.M. (1980) New trends in essential oils. Perfumer & Flavourist, 5(4), 6–16.

LAWRENCE, B.M. (1981) Progress in essential oils. Perfumer & Flavourist, 6(1), 37–41

RANDHAWA, G.S. and KAUR, S. (1995) Dill. In Advances in Horticulture. Vol 11. Medicinal

&  Aromatic  Plants,  Eds.  K.L.  Chadha  and  R.  Gupta,  Malhotra  Publishing  House, New Delhi, pp. 917–32.

SHAH, C.S.  and QUADRI, J.S. (1994) A Textbook of Pharmacognosy (10th edn.) B.S. Shah

Prakashan, Ahemdabad, pp. 198–200.

SHAH, C.S., QUADRI, J.S. and CHAUHAN, M.G. (1972) Dillapiole-free Indian dill. Indian, J. of

Pharm, 34(5) 77–8.


TIMOSHENKO, M.A. (1970) Prometryne in dill cultures. Zaschita Rastenic, 17(5), 28 (Hort. Abstr.) 43, 23

VARSHNEY, S.C. (2000) Vision 2005: Essential oil industry in India. Indian Perfum. 44(3),

101–18.

ZLATEV, S.K. (1976) Influence of meterological factors on the quantity and quality of the essential  oil  synthesized  in  dill  (Anethum  graveolons  Linn),  Rastenien  dni  Nauki.

14(5), 57–63 (Hort. abstr.) 58, 1652.








Politica de confidentialitate

DISTRIBUIE DOCUMENTUL

Comentarii


Vizualizari: 967
Importanta: rank

Comenteaza documentul:

Te rugam sa te autentifici sau sa iti faci cont pentru a putea comenta

Creaza cont nou

Termeni si conditii de utilizare | Contact
© SCRIGROUP 2019 . All rights reserved

Distribuie URL

Adauga cod HTML in site