This document summarizes the postharvest management and value addition of grapes. It discusses the varieties of grapes cultivated in India, nutritional value, and health benefits. It describes the harvesting, sorting, packaging and storage processes. Methods to reduce postharvest losses are outlined. Value-added products from grapes include wine, juice, jelly, and raisins. The document provides details on wine production processes such as destemming, crushing, fermentation, aging and pasteurization.

1. POSTHARVEST MANAGEMENT&VALUE
ADDITION OF GRAPES

2. • Grape –Vitis vinifera
• Grape fruit is botanically known as berry
• It is a deciduous woody flowering plant belongs to genus Vitis.
• Grapes can be eaten fresh as table grapes or they can be
used for making wine, jam, juice, jelly, grape seed extract,
raisins, vinegar, and grape seed oil.
• Grapes are a non-climacteric type of fruit, generally occurring
in clusters.

3. • Nutritional value of grapes per 100gr
Energy - 288 KJ
Carbohydrates - 18.1 gr
Sugars - 15.48 g
Proteins - 0.72gr
Fat - 0.16 gr
Vitamin K - 14%
Vitamin C - 4%

4. Health benefits of grapes
• Health benefits of grapes:

5. • Grape production
• Grape is an important fruit crop of India.
• Commercial grape cultivation in India is mainly for table
purpose and has reasonably high level of productivity in the
world.
• According to an estimate area under grape cultivation was
138 thousand ha with production of2980thousand MT during
2017-18
• Grape is mainly cultivated in Maharashtra followed by
Karnataka, Tamil Nadu, Mizoram and Andhra Pradesh

6. • Varieties of grapes
• The main varieties cultivated are Thompson Seedless and its clonal
• selections like , Sonaka, Super Sonaka, etc.; are Seedless among white
grapes.
• Among the coloured table grape varieties Sharad Seedless,
• Nana Purple, Flame Seedless, Red Globe, Crimson Seedless, etc. are
mainly cultivated in the country.

7. Thompson seedless Sonaka

8. Flame seedless
Red globe

9. Nana purple

10. •Post harvest losses in grapes
Postharvest loss can be defined as the
degradation in both quantity and quality of a food
production from harvest to consumption.
The postharvest loss in grapes has been recorded
by various workers within the range of 8.23 to 16
per cent in the country.
As per present estimate of 8.23 per cent, India is
loosing about 223 thousand tonnes of grapes
annually.

11. Factors affect postharvest loss in grapes:
• Varietal impact
• Some varieties show rachis browning very fast
after harvesting and result in berry shattering.
• In coloured varieties uneven coloured berries or
poorly developed colour causes post harvest
losses

13. • Insect-pests and diseases:
• Incidence of thrips has
notimpact on physical loss but
appearance of berries affected
badly
. Thrips damage

14. • Improper harvesting :
• The time of harvesting, prevailing temperature at the harvesting,
Presence of moisture on the berries and handling of grape bunches
during harvesting are major regulating factors for loss.
• Delay in pre-cooling:
• Delay in precooling results in water loss leads to browning of rachis
and reduced shelf life of grapes

15. • Packaging:
• Packing of improper grape types (including ungraded, uneven
ripened, uneven shape, size and colour grapes), cracked,
damaged fruits responsible for post-harvest economic loss,
• Use of improper packaging materials also responsible for more
postharvest loss.

16. Transportation
Post harvest losses occur due to lack of transportation facilities
Storage: Improper storage conditions as well as storage for a long
duration in such conditions always lead to increase water loss more
rapidly. It results in rachis browning
• Market:The faulty marketing process delays the supply of grapes to
retailers or wholesale supplier which results in more postharvest loss.

17. • Post harvest losses take place mainly at
• Harvesting
• Collection
• Pack-house
Transport (farm to packhouse and to market/consumer)
• Wholesale
• Retail sale

18. Measures to reduce post harvest losses
• Harvesting
• Harvesting should be done at proper time and at proper time of maturity
• Precooling
• If precooling done lately then fruits will lose moisture so that it should not
be delayed
• Grading
• While grading mechanical injuries should be avoided
• Packaging
• Avoid using of improper packaging materials

19. Harvesting
Precooling
Sorting
Washing
Sizing
Packaging
Storage
Transportation
Restoring, Resizing&Repacking
Transportation
Retailer
Consumer
Flow sheet for
post harvest
handling of
grapes

20. • Harvesting of grapes
• The time of harvest is determined primarily by the ripeness of the grape
as measured by sugar, acid and tannin levels

21. Harvesting methods
• Manual harvesting

22. • Mechanical harvesting

23. •Harvesting indices of grapes
• Appearance of waxylayer
• Berries become soft in texture
• Colour change in grapes from dark green
to light green
• Size of berries increses

24. •Maturity indices
• Berries easily detaches from
bunch
• Colour stalk changes to brown
colour

25. •Maturity induces
Soft texture Waxy layer

26. • Total soluble solids TSS content for harvesting
Purpose Brick index in degrees
Table grapes ( Anab- e shahi ) 14 - 16
(Thomson seedless) 18- 22
Raisin making 20 - 24
Juice making 18 - 24
Wine making 21 - 25

27. •Grape maturity stages

28. •Precooling
• For maximum storage life, grapes
should be precooled immediately
after harvest by forced–air cooling or
by tunnel cooling.
• Grapes are precooled to a
temperature of 0°C–2°C, preferably
within four hours, which ensures a
storage life of up to 60 days.
• An RH of 90 to 95 % is recommended

29. •Forced air cooling of grapes

30. •Sorting of grapes
• It can be done by sorting
grapebunches, or by sorting the
individualgrapes (berries)
• Thegrapes are emptied onto a
conveyor belt: the sorting table.

31. • Sorting table
• On each side of the sorting table people inspect
thegrapes and remove those that are not of top quality
Sorting of grape bunches

32. •Sorting of individual grape berries

33. •Washing of grapes
• White and red grapes were washed in winery scale with 1 % citric
acid solution or salt solution

34. • Chemical treatment
• Mold and decaying are the two main factors that reduce grape
quality during shipping and storage in retail produce sections.
.
• Sulfur dioxide as a method of controlling decay has been in
use for over 75 year
• Sulfur dioxide pads placed over the fruit packed in boxes
• The pads release sulfur dioxide, or SO2 , a chemical used to
prevent mold and decaying of table grapes.

35. Mould. Decaying of grapes

36. • Sizing
• Size is determined by the weight of bunches (in gms)
• Large sized berries have more value compared to small size of grapes
• AGMARK standards for grape size
Grade Large berries Small berris
Extra class 200 150
Class1 150 100
Class2 100 75

37. •Grape sizing
• For all varieties, other than seedless
varieties, the berries must meet a minimum
diameter of 10/16 inch.
• For all seedless varieties (Flame
Seedless, Thompson Seedless, Perlette,
Black Seedless, etc.) they must meet a
minimum diameter of 9/16 inch

39. •Packaging
• Packaging required to keep grapes in good condition until it sold and
consumed
• Different packaging materials
• 1)Basket madeup of strips of leaves
• 2)Sacs. a)Bags- small size sacs
• . b)Nets –Sacs made of open nets
• 3 )Fiber board boxes a)Solid fibre board boxes
• b)Corrugated fiber board boxes
• 4)Plastic trays
• 5) Biodegradable plastics
• 6)Pallet boxes & Shipping containers

40. • Grape packaging
• Most commonly used method of grape
packaging for long-distance shipment is
the use of perforated liners,
• External wrapping of pallets with low-
density polyethylene film can be as
effective as the liner method in preventing
grape decay.
• The pallet wrapping method works best
when used with recyclable plastic boxes,
as the plastic boxes do not absorb the
SO2
• The SO2 generator pads were developed for
use in liners inside boxes.

41. •Perforated liner bags
• This new technology generates a uniform atmosphere that protects the fruit
from excessive exposure to SO2

42. • CFB boxes

43. Plastic nets. Plastic punnets

44. • ...
• Plastic trays
Paper bags

45. Baskets Plastic nets

47. • Storage of grapes
• Store grape boxes immediately in
refrigeration when received.
• The ideal condition for grapes is
30 – 32 F with 90 – 95 percent
relative humidity.
• Grapes generally have a much
longer shelf life than other berrie
• Properly stored grapes will stay
fresh about one week.

48. • Grape storage

49. • Sulfur dioxide treatment
• Gray mold caused by the fungus Botrytis cinerea and rachis browning
as a result of
• desiccation are the two main factors that reduce table grape
postharvest quality
• The means for preventing decay during storage is the use of sulfur
dioxide(SO2),
• Dual-release (DR) SO2 generator consisting of formulations that allow
quick release plus slow release of the gas have been widely used for
table grape storage and transport
Grapes are subjected to an initial fumigation with SO2 during forced-air
cooling and then given weekly fumigations during storage.
An SO2 concentration of 7 to 10 ppm was recommended for long-term
storage of grapes

50. Sulfurdioxide -Packaging method
It is important to find the best method of
packaging that will minimize water loss while
preventing the decay that would occur if the
SO2 level was too low or high
The pallet-wrapping method is best when
used with recyclable plastic boxes rather than
cardboard ones, because there is no SO2
absorption by the plastic and appreciable
absorption by the cardboard.
Reusable plastic boxes may also be
environmentally better than the cardboard
boxes.

52. •

53. High So concentration

54. • Transportation of grapes
• Transportation of grapes in many respects depends on a grade
of grapes, durability of the skin, density of pulp, durability of an
attachment of berries to fruit stems.
• In process of maturing and over ripeness, transportability of
grapes decreases.
• Better to gather grapes for transportation somewhat immature,
rather than overripe.

55. Transportation of grapes

56. Value addition of grapes

57. Processing of grapes

58. Ripe grapes
Removal of stems
Crushing(basket press)
Filling jar up to three fourth
Addition of sugars (20 to 24%)
Adjustment of pH(0.6 to 0.8% acid)
Addition of preservative
(KMS 1.5 gr/1Kg grapes)
Keeping for an hour
Addition of wine yeast
Fementation( for 10 days)
Filtration
fermentation( for 10 days)
Racking (Syphoning off clear liquid)
Fining& Filtration (Bentonite)
AGING(Maturation)(6to 8 months)
Pasteurization at 85 deg.C(for 2min)
Bottling
Crown corking
Pasteurization at 820 C for 2 min
Cooling
Storage
Flow chart for preparation of wine

59. •Wine varieties
• Cabernet Franc. Cabernet
Sauvignon. Carmenere. Chardonnay.Grenache.
Malbec.
• Merlot. Muscat Ottonel. Nebbiolo. Pinotage. Pinot Grigio /
Gris. Pinot Noir. Riesling.
• Sauvignon Blanc. Semillon. Shiraz / Syrah. Tempranillo.
Viognier. Zinfandel

60. • Cabernet Malbec

61. Wine production

62. • Destemming
• Destemming consists of separating grapes from the herbaceous
parts of the clusters and the stems that are unnecessary
• . Typically, the destemming is undertaken before crushing with the
purpose of lowering the development of tannins and vegetative
flavours in the finished wine
• Stems can be high in water, which can decrease the colour and
alcohol level of the finished wine.
• The stems can also take up a great deal of space, so the reduction in
volume will also reduce the total tank capacity required for
fermentation
• The stems can also take up a great deal of space, so the reduction
in volume will also reduce the total tank capacity required for
fermentation.

64. • Crushing
• Crushing Is the first step In turning Grapes into Wine
• Crushing simply breaks grape berries, allowing the juice, pulp, and
seeds to mingle with the skins and stems of the grapes.

66. •Chaptalization
• Chaptalizing is the act of adding sugar to a grape must in order to increase the
alcohol content of the finished wine.
• Yeast consumes sugars toproduce
alcohol
If we add sugar to grape juice before
or during fermentation the yeast
will have moresugar to convert thus
yielding higher alcohol levels.

67. • Adjusting of pH
• Adding potassium bicarbonate or ACIDEX® to remove
some acidity andraise the pH.
• Carrying out a malolactic fermentation (MLF) to raise the pH.
Cold stabilizing to reduce acidity, which can increase or
decrease pH.
• Simply adding water to dilute the acidity and increase the pH.

68. •Addition of preservatives
• Sulphur dioxide
• (Preservative 220),
• Potassium metabisulphite
(preservative 224)
• In white wine, Ascorbic Acid
(300) can also be added, but it is
technically an anti-oxidant rather
than a preservative.

69. •Addition of wine yeast
• Saccharomyces ellipsoideus
• The role of yeast in winemaking is the most important
element that distinguishes wine from grape juice.
• In the absence of oxygen, yeast converts the sugars of
wine grapes into alcohol and carbon dioxide through the
process of fermentation.
• Yeast should be added in the dosage of 20 ml/5Kg of
grape

70. • Fermentation
• After adding wine yeast the wine is pumped into tanks to
begin fermentation.
• The process of fermentation in winemaking turns grape juice
into an alcoholic beverage.
• The more sugars in the grapes the higher the potential alcohol
level of the wine if the yeast is allowed to carry out
fermentation
• The temperature during fermentation of wine is 700 F to 850 F
or 20 oto 30oC

72. • Racking (Syphoning of clear liquid)
• Racking is the process of moving wine from one vessel to
another using gravity with the purpose of removing the
sediment and lees.
• This step is completed to help clarify the wine, prevent negative
flavors developing from the lees and sediment, and create a
desired flavor profile.
• Racking takes place an average of three times during the
winemaking process. 1)once during fermentation,
• 2)once after fermentation and
• 3) after fining.

74. •Fining of wine
• The addition of a substance or mixture of substances to
the wine, in order to clarify, stabilise or modify its organoleptic
qualities, which is subsequently removed.
• Examples of fining agents are
• 1)Bentonite, which is used to remove proteins and
2)Gelatin, which is used for clarification.

76. •Filtration
Passing wine or must through a media in order to 'strain out' the particles
suspended in it.
This is a purely physical process and involves the separation of liquid (wine)
from any sediment deposits or 'suspended' particles.

78. Aging (Maturation) of wine
• Wine aging refers to a group of reactions that tend to improve the
taste and flavor of a wine over time.
• The term wine 'maturation' refers to changes in wine after
fermentation and before bottling.
• During this period, the wine is subjected to various treatments, such
as malolactic fermentation, clarification, stabilization, and bulk
storage.
• The important feature of this phase is that the wine is periodically
exposed to air where many oxidative reactions influence the
changes in wine composition

80. • Changes in wine due to maturation and aging
• During the process of maturation and aging, the most obvious
change occurs in the color of the wine.
• In white wine, the color becomes golden, and later, can turn to
brown if the wine is aged too long.
• In red wine, the purple and violet tints are progressively replaced by
orange and brick red colors.
• The grape-derived aromas fade, and more complex and pleasing
aromas develop. The taste of the wine also changes
• Astringent and harsh tastes are replaced by smoother, rounder
tastes.
• The various taste and aroma components integrate, yielding
complex, rich, and delicious wines.

82. •Pasteurization
A wine pasteurization unit has been defined as heating to a constant
temperature to kill bacteria and other microbes
It will be done two times
1)Before bottling heating to a temperature of 85 deg.C. for 2 min
2)After crown corking to a temperature of 82 deg.C. for 20 min

83. •Bottling
• Bottling is the final stage in the winemaking process and is very
important to the final finished product.
• During bottling, the year's harvested and produced wines are
bottled into their final storage vessels that can include traditional
glass bottles, Tetra Paks®, bag-lined boxes and cans

84. •Wine cooling & Storage
• Wine coolers are most basic, standalone units designed to maintain a
consistent temperature the one suitable for serving rather than long-
term storage
• Whereas a winecellar is a cabinet or an entire room that stores wine in
optimal conditions for long-term aging: a consistent temperature (about
55° F), ...
•

85. Flow sheet for raisin making
Picking
Spreading
Drying
Turning
Rolling
Boxing
Transportation
Storage

86. •Raisins
• Raisin is a dried grape
• In this temperature is reduced from 75 % to
under 15 %
• In this colour of grape changes to a brownish
pulple
• Harvesting of grapes for raisin
• Grapes are harvested when TSS reached to
20 – 24%

87. • Varieties suitable for raisin making
• The most important grapes for raisin production include Thompson Seedless,
Black Corinth, Fiesta, Muscats, and Sultans.
• By far, the most widely grown raisin grape is the Thompson Seedless variety

88. • Picking
• 1. Place the pan directly under the fruit to be
picked to catch loose clusters or berries.
• 2. Use a knife to cut clusters from the vine and
to cut tangled clusters in half.
• Avoid cutting or crushing berries.
• The juice accumulates soil, attracts vinegar
flies and dried fruit begins to rot.

89. • Spreading of grapes
• Spread the fruit evenly on the trays, being careful not to mash the
berries
• remove all leaves and refuse.
• Keep loose berries from rolling off of the bottom end of the tray by
placing several clusters along the bottom before spreading.
• Keep the trays uniform in weight for even drying.
• Do not overload trays, since that will slow drying and increase the
potential for rot, especially in the event of rain. Keep foot traffic out
of the drying area.
• 9. Do not kick sand onto the drying trays.
• 10. Place the trays far enough north on the terrace to minimize
shading

91. • Drying of grapes
• Before drying, the grape bunches treated with grape
dying oil.
• It is prepared by mixing of 15 ml ethyl oleate and 25 g
potassium carbonate in one liter of water.
• The grape bunches dipped in this solution for 2-5
minuets.
• Then spread ion single layer on mesh under sheds.
• High air temperature and rapid air movement lower
relative humidity are suitable climatic conditions for
faster drying of grapes.
• Lower moisture contained raisins become hard and
high moisture contained raisins looses quality during
storage.

92. • Turning
• Turning is a way to mix the grapes on the tray to facilitate faster and more
even drying.
Turning is done during conditions
1)Cool weather conditions
2)During slow drying
3) Trays in which some rot is
Progressing in the bottom-most fruit;
4) After a rain.
Turn when the berries on the top layer are brown and shriveled.

93. • Rolling of grapes
• The rolling operation greatly slows the drying process, protects the
fruit from over-drying or caramelization, provides rain protection
• The fruit to be rolled will continue to cure and equalize their
moisture in the rolls and bins
• At 95°F (28°C) or above, it is best to roll the raisins on the heavy side
to prevent over drying
• The production of Quinones undergoes more reactions which
eventually form brown pigments on the surface of the food.
• A desirable enzymatic browning reaction( Caramelization) is
involved in the process of grapes becoming raisins

94. • Boxing
• Raisins must be at 16% or less moisture
content to achieve high quality.
• Lower moisture content receives greater
price in the market.
• There are two main ways to box raisins.
• Yard Boxing is where the raisins are
collected and then sorted before boxed.
• Field Boxing is when raisins are picked up
and put into containers in the field.

95. • HANDLING RAINED-ON AND HIGH MOISTURE RAISINS
• Proper handling of rained-on and high-moisture raisins is critical to
minimizing mold infection, fermentation, and imbedded sand.
• Practices to minimize damage and infection:
• 1.Slip trays 1- 2 inches to prevent their sticking to the soil.
• 2. Turn trays as soon as possible to expose bottom fruit.
• 3. Discard fruit stuck to the bottom of the trays, use new trays as needed.
• 4. Pick moldy and rotten fruit off the trays as needed.
• 5. Get rolled fruit out of the field as soon as possible.
• Do not fill binds with raisins above 18 % moisture content.

96. •Kishmish
• Kishmish also made by drying grapes
• Kishmish-made from only dried seedless grapes
• Raisins- made from drying of grapes (seeded/seedless)

97. Grape (coloured/white)
Removal of stalk
Crushing(basket press)
Juice extraction
Filtration
Clarfication
(low temp storage for 3to 4 months)
Filtration
Bottling
Crown corking
Pasteurization
Cooling
Storage
Flow sheet
for for
grape juice
making

99. • Harvesting of grapes for juice making
• Grapes are harvested for juice when TSS content is 18 – 24%
• Washing of grapes
• Remove stems and leaves from grapesand wash thoroughly under
running

100. • Removal of stalk
• Separate the stalk from grape because it
contains some tannins and holds which
reduces grape quality
• Crushing (Basket press)
• Crushing simply breaks grape berries,
allowing the juice, pulp, and seeds to
mingle with the skins and stems of
the grapes

101. • Juice extraction
• Grape juice can be extracted using either a
hot-press or a coldpress technique.
• Extraction temperature has a significant
effect on quality parameters of juice.
• The hot-press method yielded more juice
than cold pressing.
• Within a cultivar, pressing method had no
effect on soluble solids but did cause
significant differences in pH and color density

102. • Filtration and Clarification
• After pressing, the must from white grapes contains significant grape
solids and is very turbid.
• To improve ferment quality, the juice is often clarified.
• The objectives of this clarification are to remove any suspended solid
particles
• Clarification is normally achieved by:
Low temperature storage for 3 to 4 months for settling of cream of tartar
Cold settling overnight or longer (ideally below 15ºC), possibly with
pectolytic enzymes added, followed by racking.
• Centrifugation
• Diatomaceous earth filtering

104. • Bottling of juice
• After clarification again filtration bill be done
• Then juice is transferred into bottles

105. • Pasteurization
• Grape juice can be red or white. Thejuice must then
be pasteurizedimmediately so that it won't ferment into wine.
• Grape juice should be pasteurized at a temperature of 73.9 deg.C
to 87. 8 deg .C

106. • Cooling and storage of grape juice

107. • Grape vinegar
• Vinegar is made through fermentation
of sugars into acetic acid by
microorganisms.
• Grape vinegar is synonymous with
wine vinegar and is made by further
fermentation of wine.
• It's used as a condiment, for pickling
and to prepare some sauces.

108. • Grape candy
• Place sugar, glucose and 125 ml water
in a saucepan over medium heat.
• Stir to dissolve sugar, then cook for 5
minutes or until mixture reaches 155˚C
on a sugar thermometer.
• Remove from heat, then dip fruit into
syrup to coat.
• Insert lollypop sticks into holes of
square-grated cake rack and set aside
for 30 minutes or until candy is set.

109. • Pekmez
• Evaporated grape syrup pekmez has been traditionally
and industrially produced
• Pekmez is produced in low heat evaporation steps,
commercially sold and commonly consumed in viscous
liquid and solid forms
• The color of the pekmez changes from dark brown to
white depending on the processing conditions,
concentration, types of bleaching agents, heat and
mixing rate.

110. • Grape spreads
• The process of making grape jelly, jam, preserves, butter or marmalade
consists mainly of cooking the grapes and/or their juice in combination
with sweeteners and pectins.
• The ratio of minimum total soluble solids to fruit sweetener
Finished
product
Soluble solids Parts by weight
fruit
Parts by weight
sweetner
Grape butter 43%minimum 5 2
Grape jelly 65%minimum 45 55
Grape jam 68%minimum 45 55

111. • Grape waste produts
• Stems and pomance are main waste products
• The stems are used for preparing cream of tartar
• Oil can be extracted from seeds cake is used as cattle feed