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Introduction to Fruits and Vegetables

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Steven C Seideman, PhDSteven C Seideman, PhD

Extension Food Processing SpecialistExtension Food Processing Specialist

Cooperative Extension ServiceCooperative Extension Service

University of ArkansasUniversity of Arkansas

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Introduction to Fruits and Vegetables

This module covers some of the basic fruits This module covers some of the basic fruits and vegetables, their structure and and vegetables, their structure and processing.processing.

It is a brief summary of Chapter 18 It is a brief summary of Chapter 18 “ Vegetables and Fruits” from the book “ Vegetables and Fruits” from the book FOOD SCIENCE by Norman N. Potter and FOOD SCIENCE by Norman N. Potter and Joseph H. Hotchkiss. Published by Kluwer Joseph H. Hotchkiss. Published by Kluwer Academic/Plenum Publishers. New York.Academic/Plenum Publishers. New York.

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Fruits and Vegetables

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Vegetables and Fruits

Fruits and vegetables are cultivated and Fruits and vegetables are cultivated and processed similarly.processed similarly.

Many vegetables are fruits by the truest Many vegetables are fruits by the truest botanical definition.botanical definition.

Fruits are defined as “those portions of a Fruits are defined as “those portions of a plant which houses the seeds”- Therefore plant which houses the seeds”- Therefore tomatoes, cucumbers, peppers, okra, sweet tomatoes, cucumbers, peppers, okra, sweet corn etc are considered fruits.corn etc are considered fruits.

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Vegetables and Fruits

The important distinction between fruits The important distinction between fruits and vegetables is made based on their and vegetables is made based on their usage.usage.

VegetablesVegetables are those plant items generally are those plant items generally eaten with the main course of a meal.eaten with the main course of a meal.

FruitsFruits are those plant items commonly are those plant items commonly eaten alone or as a dessert.eaten alone or as a dessert.

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Classification of Certain Vegetables

Generally classified by their location on a Generally classified by their location on a plant such as roots, leaves, stems, buds, etc..plant such as roots, leaves, stems, buds, etc..

Vegetables/fruits can be classified as earth, Vegetables/fruits can be classified as earth, herbage or fruit vegetables.herbage or fruit vegetables.

The next chart shows the classification The next chart shows the classification system of vegetables.system of vegetables.

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Fruits

Fruits are the mature ovaries of plants with their Fruits are the mature ovaries of plants with their seeds.seeds.

The edible portion of most fruits is the fleshy part The edible portion of most fruits is the fleshy part of the pericarp or vessel surrounding the seeds.of the pericarp or vessel surrounding the seeds.

Fruits in general are acidic and sugary.Fruits in general are acidic and sugary. Fruits can be classified by botanical structure, Fruits can be classified by botanical structure,

chemical composition and climatic requirements.chemical composition and climatic requirements.

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Fruit Classifications

BerriesBerries- usually quite small- grapes, cranberries- usually quite small- grapes, cranberries MelonsMelons-large and have a tough outer rind--large and have a tough outer rind-

watermelons, cantelopewatermelons, cantelope DrupesDrupes-contain single pits- apricots, cherries, -contain single pits- apricots, cherries,

peaches and plums.peaches and plums. PomesPomes-contain many pits- apples, pears.-contain many pits- apples, pears. Citrus FruitsCitrus Fruits-high citric acid-oranges, grapefruit, -high citric acid-oranges, grapefruit,

lemonslemons Tropical fruitsTropical fruits-require warm temperatures- bananas, -require warm temperatures- bananas,

dates, figs, pineapple, papayas, mangosdates, figs, pineapple, papayas, mangos

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Composition Fruits and vegetables have similar compositions.Fruits and vegetables have similar compositions. They are very high in water content (70-85%), They are very high in water content (70-85%),

relatively high in carbohydrates but low in fat (less relatively high in carbohydrates but low in fat (less than 0.5%) and protein (less than 3.5%) and usually than 0.5%) and protein (less than 3.5%) and usually contain useful vitamins.contain useful vitamins.

The carbohydrate portion can be further broken The carbohydrate portion can be further broken down into digestible and indigestible parts (sugars down into digestible and indigestible parts (sugars and starches vs pectins and cellulose material).and starches vs pectins and cellulose material).

Vitamin A is found in yellow-orange fruits and Vitamin A is found in yellow-orange fruits and vegetables and leafy, green vegetables.vegetables and leafy, green vegetables.

Vitamin C is found in citrus fruits, tomatoes and Vitamin C is found in citrus fruits, tomatoes and green, leafy vegetables.green, leafy vegetables.

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Structural Features

The structural material of the edible portion The structural material of the edible portion of most fruits and vegetables is the of most fruits and vegetables is the parenchyma cell. Although parenchyma parenchyma cell. Although parenchyma cells of different fruits and vegetables differ cells of different fruits and vegetables differ somewhat is gross size and appearance, all somewhat is gross size and appearance, all have essentially the same fundamental have essentially the same fundamental structure. See diagram on next page.structure. See diagram on next page.

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Structural Features

CellsCells- The cells of the edible portion of most fruits - The cells of the edible portion of most fruits and vegetables are characterized by a large, water and vegetables are characterized by a large, water filled vacuole. Sugars and other water-soluble filled vacuole. Sugars and other water-soluble compounds may also exist in this area. Cellulosic compounds may also exist in this area. Cellulosic material (complex carbohydrates) surround the material (complex carbohydrates) surround the vacuoles and also form the cell wall. Protein is vacuoles and also form the cell wall. Protein is also in the cell walls. The next table shows the also in the cell walls. The next table shows the Structure and Chemical Components of Plant Structure and Chemical Components of Plant Cells.Cells.

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Texture

The range of textures encountered in fresh The range of textures encountered in fresh and cooked vegetables and fruit is great and cooked vegetables and fruit is great and, to a large extent, can be explained by and, to a large extent, can be explained by changes in specific cellular components. changes in specific cellular components. Since plant tissues generally contain more Since plant tissues generally contain more than two-thirds water, the relationships than two-thirds water, the relationships between these components and water between these components and water further determine textural differences.further determine textural differences.

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Textural Features

TurgorTurgor- The rigidity of cells is due to being - The rigidity of cells is due to being filled with water. The cell membranes are filled with water. The cell membranes are elastic and “give and take” with changes in elastic and “give and take” with changes in water content. Living plants have a high water content. Living plants have a high turgor, resulting in crispness. When plant turgor, resulting in crispness. When plant tissues are damaged or destroyed by tissues are damaged or destroyed by storage, freezing, cooking or other causes, storage, freezing, cooking or other causes, turgor pressure is lost, leaving the tissue turgor pressure is lost, leaving the tissue soft and wilted.soft and wilted.

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Textural Features

Cellulose, Hemicellulose and LigninCellulose, Hemicellulose and Lignin- Cell - Cell walls in young plants are very thin and are walls in young plants are very thin and are composed largely of cellulose. As the plant composed largely of cellulose. As the plant ages, cell walls tend to thicken and become ages, cell walls tend to thicken and become higher in hemicellulose and lignin. These higher in hemicellulose and lignin. These materials are fibrous and tough and are not materials are fibrous and tough and are not significantly softened by cooking.significantly softened by cooking.

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Textural Features

Pectin and related substances are complex Pectin and related substances are complex polymers of sugar-acid derivatives.polymers of sugar-acid derivatives.

Pectins are the cement-like substance found Pectins are the cement-like substance found especially in the middle lamella which helps especially in the middle lamella which helps hold plant cells together.hold plant cells together.

Fruits and vegetables contain a natural Fruits and vegetables contain a natural occurring enzyme, pectin methyl esterase occurring enzyme, pectin methyl esterase that hydrolyzes pectin. that hydrolyzes pectin.

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Textural Features

It is often desirable to firm the texture of fruits and It is often desirable to firm the texture of fruits and vegetables.vegetables.

By adding calcium ions to fruits and vegetables By adding calcium ions to fruits and vegetables before processing, calcium pectates are formed before processing, calcium pectates are formed from pectins that increase structural integrity.from pectins that increase structural integrity.

Thus it is a common commercial practice to add Thus it is a common commercial practice to add low levels of calcium salts to tomatoes, apples and low levels of calcium salts to tomatoes, apples and other fruits and vegetables prior to canning and other fruits and vegetables prior to canning and freezing.freezing.

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Color and Color Changes

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Color and Color Changes

Much of the appeal of fruits and vegetables Much of the appeal of fruits and vegetables in our diets is due to their desirable colors.in our diets is due to their desirable colors.

The pigments and color precursors found in The pigments and color precursors found in fruits and vegetables occur in the cellular fruits and vegetables occur in the cellular plastid inclusions. (e.g. chloroplasts).plastid inclusions. (e.g. chloroplasts).

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26Photo courtesy of USDA

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Chlorophylls Chlorophylls are largely contained within the Chlorophylls are largely contained within the

chloroplasts and have a primary role in the chloroplasts and have a primary role in the photosynthetic production of carbohydrates from photosynthetic production of carbohydrates from carbon dioxide and water.carbon dioxide and water.

The bright green color of leaves is largely due to The bright green color of leaves is largely due to oil-soluble chlorophylls.oil-soluble chlorophylls.

When cells are destroyed by aging, processing or When cells are destroyed by aging, processing or cooking, the proteins are denatured and the cooking, the proteins are denatured and the chlorophyll in changed to pheophytin which is olive chlorophyll in changed to pheophytin which is olive green to brown in color.green to brown in color.

For this reason, peas, beans, spinach and other green For this reason, peas, beans, spinach and other green vegetables lose their bright green upon cooking.vegetables lose their bright green upon cooking.

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Carotenoids Pigments belonging to the carotenoid group are fat Pigments belonging to the carotenoid group are fat

soluble and range in color from yellow through soluble and range in color from yellow through orange to red.orange to red.

Important carotenoids include the orange of carrot, Important carotenoids include the orange of carrot, corn, apricot, peach, citrus fruits and squash; the corn, apricot, peach, citrus fruits and squash; the red lycopene of tomatoes, watermelon and apricot red lycopene of tomatoes, watermelon and apricot and the yellow-orange xanthophyll of corn, peach, and the yellow-orange xanthophyll of corn, peach, paprika and squash.paprika and squash.

In food processing, the carotenoids are fairly In food processing, the carotenoids are fairly resistant to heat, changes in pH and water leaching resistant to heat, changes in pH and water leaching since they are oil soluble. However, they are very since they are oil soluble. However, they are very sensitive to oxidation which results in both color sensitive to oxidation which results in both color loss and destruction of vitamin A.loss and destruction of vitamin A.

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Anthocyanins

These pigments represent a group known as These pigments represent a group known as flavonoids that are water soluble and commonly flavonoids that are water soluble and commonly present in the juices of fruits and vegetables.present in the juices of fruits and vegetables.

They range in color from purple, blue to red found They range in color from purple, blue to red found in grapes, berries, plums and cherries.in grapes, berries, plums and cherries.

The color expressed is pH dependent (violet to The color expressed is pH dependent (violet to blue in alkaline media to become red upon the blue in alkaline media to become red upon the addition of natural occurring or intentionally addition of natural occurring or intentionally added acid).added acid).

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Flavonoids

The yellow flavonoids are structurally related to The yellow flavonoids are structurally related to anthocyanins and comprise a large group of anthocyanins and comprise a large group of chemicals found in plant foods. They are also pH chemicals found in plant foods. They are also pH dependent tending toward a deeper yellow in dependent tending toward a deeper yellow in alkaline media.alkaline media.

Thus potatoes and apples tend to become Thus potatoes and apples tend to become somewhat yellow when cooked in water with a pH somewhat yellow when cooked in water with a pH of 8.0 or higher. Acidification to pH of 6.0 or of 8.0 or higher. Acidification to pH of 6.0 or lower favors a whiter color.lower favors a whiter color.

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Tannins Tannins are complex mixtures of phenolic Tannins are complex mixtures of phenolic

compounds found in plants. compounds found in plants. Under most circumstances, they are colorless but Under most circumstances, they are colorless but

on reaction with metal ions, they form a range of on reaction with metal ions, they form a range of dark-colored complexes which range from red, dark-colored complexes which range from red, brown, green or black.brown, green or black.

Water soluble tannins appear in the juices Water soluble tannins appear in the juices squeezed from grapes, apples and other fruits as squeezed from grapes, apples and other fruits as well as in the brews of tea and coffee.well as in the brews of tea and coffee.

If in high enough levels, can contribute an If in high enough levels, can contribute an astringent flavor note.astringent flavor note.

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Activities of Living Systems

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Activities in Living Systems

Fruits and vegetables continue to respire after Fruits and vegetables continue to respire after harvest meaning they take in oxygen and give off harvest meaning they take in oxygen and give off carbon dioxide, water and heat.carbon dioxide, water and heat.

The moisture and heat buildup can cause serious The moisture and heat buildup can cause serious damage to fruits and vegetables unless quickly damage to fruits and vegetables unless quickly controlled.controlled.

Numerous changes occur to starches, sugars, Numerous changes occur to starches, sugars, pectins etc immediately after harvest.pectins etc immediately after harvest.

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Activities in Living Systems

The quality decline in stored respiring fruits and The quality decline in stored respiring fruits and vegetables is termed “senescence” and results vegetables is termed “senescence” and results from the continued enzymatic activity.from the continued enzymatic activity.

The two primary factors that influence senescence The two primary factors that influence senescence rate are temperature and composition of the rate are temperature and composition of the storage atmosphere.storage atmosphere.

Reduced temperatures, lower oxygen rates and Reduced temperatures, lower oxygen rates and raised carbon dioxide levels reduce the rate of raised carbon dioxide levels reduce the rate of senescence and increase storage times.senescence and increase storage times.

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The Harvest and Processing of Vegetables

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Varietal Differences

Food scientists and food processors Food scientists and food processors appreciate the substantial differences that appreciate the substantial differences that cultivars of a given vegetable possess.cultivars of a given vegetable possess.

In addition to differences in response to In addition to differences in response to weather and pest resistance, cultivars of a weather and pest resistance, cultivars of a given vegetable differ in size, shape, time of given vegetable differ in size, shape, time of maturity and resistance to physical damage.maturity and resistance to physical damage.

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Harvesting and Preprocessing Considerations

When vegetables are maturing in the field, they When vegetables are maturing in the field, they are changing from day to day. There is a time are changing from day to day. There is a time when the vegetables will be at peak quality from when the vegetables will be at peak quality from the standpoint of color, texture and flavor. the standpoint of color, texture and flavor.

Because the peak quality lasts only briefly, Because the peak quality lasts only briefly, harvesting and processing of several vegetables, harvesting and processing of several vegetables, including tomatoes, corn and peas, are rigidly including tomatoes, corn and peas, are rigidly scheduled to capture this peak quality.scheduled to capture this peak quality.

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Vegetable Processing

Washing-Washing-vegetables are washed not only to vegetables are washed not only to remove field soil and surface remove field soil and surface microorganisms but also fungicides, microorganisms but also fungicides, insecticides and other pesticides.insecticides and other pesticides.

Skin removalSkin removal-There are numerous methods -There are numerous methods of removing the skins from vegetables of removing the skins from vegetables ranging from a hot alkaline soak that softens ranging from a hot alkaline soak that softens the skin to the use of steam under pressure.the skin to the use of steam under pressure.

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Vegetable Processing

Cutting and TrimmingCutting and Trimming- Many vegetables - Many vegetables require various kinds of cutting, stemming, require various kinds of cutting, stemming, pitting or coring.pitting or coring.

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Vegetable Processing BlanchingBlanching-Most vegetables that do not receive a -Most vegetables that do not receive a

high-temperature heat treatment (as in normal high-temperature heat treatment (as in normal canning) must be heated to a minimal temperature canning) must be heated to a minimal temperature to inactivate natural enzymes before processing or to inactivate natural enzymes before processing or storing even when frozen. This is known as storing even when frozen. This is known as “blanching”.“blanching”.

Table 18.4 shows minimum blanch times of some Table 18.4 shows minimum blanch times of some vegetables.vegetables.

Too little blanch time is ineffective and too much Too little blanch time is ineffective and too much time damages vegetables by excessive cooking.time damages vegetables by excessive cooking.

If not blanched properly, off-flavors, off-colors If not blanched properly, off-flavors, off-colors and poor textures will develop.and poor textures will develop.

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Vegetable Processing

CanningCanning-Canning refers to the science of -Canning refers to the science of placing the desired vegetable in a can, placing the desired vegetable in a can, evacuating the air, sealing it and heating to evacuating the air, sealing it and heating to a temperature to totally destroy all living a temperature to totally destroy all living organisms.organisms.

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Fruit Processing

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Varietal Differences

As with vegetables, the diversity of kinds of As with vegetables, the diversity of kinds of fruit is further enlarged by the numerous fruit is further enlarged by the numerous cultivars of a given fruit.cultivars of a given fruit.

For example, there are over 1,000 varieties For example, there are over 1,000 varieties of apples and over 3,000 varieties of pears.of apples and over 3,000 varieties of pears.

Although some fruit is marketed fresh, most Although some fruit is marketed fresh, most is further processed into a wide range of is further processed into a wide range of products.products.

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Fruit Quality Fruit quality depends on tree stock, growing Fruit quality depends on tree stock, growing

practices and weather conditions. practices and weather conditions. Most important to quality is the degree of maturity Most important to quality is the degree of maturity

and ripeness when picked and the method of and ripeness when picked and the method of harvesting.harvesting.

Maturity Maturity is the condition when the fruit is ready to is the condition when the fruit is ready to eat or, if picked, will become ready to eat on eat or, if picked, will become ready to eat on further ripening.further ripening.

RipenessRipeness is that optimum condition when color, is that optimum condition when color, flavor and texture have developed to the peak. flavor and texture have developed to the peak.

Some fruits are picked when they are mature but Some fruits are picked when they are mature but not yet ripe (e.g. cherries, peaches).not yet ripe (e.g. cherries, peaches).

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Fruit Harvesting and Processing

Much of the harvesting of most fruits is still Much of the harvesting of most fruits is still done by hand. This labor may represent done by hand. This labor may represent about half the cost of growing fruit.about half the cost of growing fruit.

WashingWashing-fruit is washed to remove soil, -fruit is washed to remove soil, microorganisms and pesticide residues.microorganisms and pesticide residues.

SortingSorting- Field fruit must be sorted by size - Field fruit must be sorted by size and quality which defines the next steps in and quality which defines the next steps in processing.processing.

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Fruit Harvesting and Processing

FreezingFreezing- Large amounts of fruits are frozen each - Large amounts of fruits are frozen each year for further use. Freezing is considered far year for further use. Freezing is considered far superior to canning for firmness.superior to canning for firmness.

BlanchingBlanching- Fruits are generally not heat blanched - Fruits are generally not heat blanched because the heat causes loss of turgor, resulting in because the heat causes loss of turgor, resulting in sogginess and juice drainage after thawing. sogginess and juice drainage after thawing. Instead, chemical antioxidants are used. If Instead, chemical antioxidants are used. If blanching is to be done, calcium salts are added to blanching is to be done, calcium salts are added to the blanching water to form calcium pectates.the blanching water to form calcium pectates.

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Beverages

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Why are Beverages Consumed?

Nutritive valueNutritive value Thirst-quenching propertiesThirst-quenching properties Stimulating effectsStimulating effects PleasurePleasure

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Major Beverage Consumption

BeverageBeverageCarbonated Soft DrinksCarbonated Soft DrinksCoffeeCoffeeMilkMilkBeerBeerBottled WaterBottled WaterSelected Fruit JuicesSelected Fruit JuicesTeaTeaFruit drinks, cocktailsFruit drinks, cocktailsWineWine

Gallons/person/yearGallons/person/year48.848.824.324.323.723.722.122.116.016.014.214.28.48.47.97.91.91.9

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Juice Processing

ExtractionExtraction-Fruit is pressed or ground to -Fruit is pressed or ground to yield the juice.yield the juice.

ClarificationClarification- Resulting juice may contain - Resulting juice may contain small particles of pulp and other debris. small particles of pulp and other debris. Typically, commercial enzymes are added Typically, commercial enzymes are added to the juice to digest the suspended to the juice to digest the suspended particles. Then the juice is centrifuged to particles. Then the juice is centrifuged to remove the denser particles.remove the denser particles.

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Juice Processing- Continued

DeaerationDeaeration- Air is removed to prevent - Air is removed to prevent oxidation and losses in vitamin C.oxidation and losses in vitamin C.

PasteurizationPasteurization- performed to reduce - performed to reduce microbial counts and inactivate enzymes.microbial counts and inactivate enzymes.

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Fruit Juice Concentrates

Since most juices have a very low solids Since most juices have a very low solids content, the juice may be concentrated to content, the juice may be concentrated to provide a more valuable product for provide a more valuable product for shipping. The water that is evaporated shipping. The water that is evaporated contains significant amounts of volatile contains significant amounts of volatile flavor compounds. These are recaptured flavor compounds. These are recaptured and added back to the juice or used as and added back to the juice or used as flavorings for other products.flavorings for other products.

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Organic Foods

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Organic Foods

““Organic” is a labeling term that denotes Organic” is a labeling term that denotes products produced under the authority of products produced under the authority of the Organic Foods Production Act. The the Organic Foods Production Act. The principle guidelines for organic production principle guidelines for organic production are to use materials and practices that are to use materials and practices that enhance the ecological balance of natural enhance the ecological balance of natural systems and that integrates the parts of the systems and that integrates the parts of the farming system into an ecological whole.farming system into an ecological whole.

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Organic Foods

Organic does not refer to the food itself but to how Organic does not refer to the food itself but to how it is produced. Organic food production is based it is produced. Organic food production is based on a system of farming that maintains and on a system of farming that maintains and replenishes the fertility of the soil. Organic foods replenishes the fertility of the soil. Organic foods are produced without the use of synthetic are produced without the use of synthetic pesticides and fertilizers. Organic foods are pesticides and fertilizers. Organic foods are minimally processed to maintain the integrity of minimally processed to maintain the integrity of the food without artificial ingredients, the food without artificial ingredients, preservatives or irradiation.preservatives or irradiation.

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Is Organically Grown Produce Healthier than other Produce?

Certified organic produce is not essentially Certified organic produce is not essentially healthier than produce that has been grown healthier than produce that has been grown under non-organic conditions. The under non-organic conditions. The nutritional content of a particular vegetable nutritional content of a particular vegetable doesn’t change. But the lack of synthetic doesn’t change. But the lack of synthetic pesticide residues on organically grown pesticide residues on organically grown produce may make for a safer product. produce may make for a safer product. Organic products may also have higher Organic products may also have higher incidences of pathogenic bacteria.incidences of pathogenic bacteria.

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Organic Regulations

The USDA regulations on the definition, The USDA regulations on the definition, labeling and requirements for organic can labeling and requirements for organic can be found at be found at www.ams.usda.gov/nopwww.ams.usda.gov/nop..

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Biotechnology

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Biotechnology

Agricultural BiotechnologyAgricultural Biotechnology is a collection of is a collection of scientific techniques, including genetic engineering, scientific techniques, including genetic engineering, that are used to create, improve or modify plants, that are used to create, improve or modify plants, animals and microorganisms. Using conventional animals and microorganisms. Using conventional techniques such as selective breeding, scientists techniques such as selective breeding, scientists have been working to improve plants and animals have been working to improve plants and animals for human benefit for hundreds of years. Modern for human benefit for hundreds of years. Modern techniques now enable scientists to move genes techniques now enable scientists to move genes (and therefore desirable traits) in ways they could (and therefore desirable traits) in ways they could not before and with greater ease and precision.not before and with greater ease and precision.

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Biotechnology

BiotechnologyBiotechnology is literally the insertion of is literally the insertion of pieces of DNA into a plants DNA. Thus, the pieces of DNA into a plants DNA. Thus, the inheritable and specific properties and traits inheritable and specific properties and traits can be incorporated into the plants genetics.can be incorporated into the plants genetics.

Desirable traits such as resistance to plant Desirable traits such as resistance to plant diseases and viruses or quality and storage diseases and viruses or quality and storage attributes can be specifically “engineered” attributes can be specifically “engineered” into plants.into plants.

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Benefits of Biotechnology

Crop resistance to disease, pests etcCrop resistance to disease, pests etc Improved shelf life of foodsImproved shelf life of foods Optimization of the enzymes used in food Optimization of the enzymes used in food

processingprocessing Environmental impacts through lower Environmental impacts through lower

energy costs and less pesticide/ herbicide energy costs and less pesticide/ herbicide use.use.

Improved health through dietary impacts.Improved health through dietary impacts.

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Negatives of Biotechnology

Who owns the control of patented genes Who owns the control of patented genes and biotechnology techniques?and biotechnology techniques?

Cross-pollination of adjacent crops.Cross-pollination of adjacent crops.

Allergenicity of new proteins.Allergenicity of new proteins.

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Crops that have been Genetically Modified

Soybeans-reduced Soybeans-reduced saturated fatsaturated fat

Soybeans-resistant to Soybeans-resistant to pestspests

Soybeans- resistant to Soybeans- resistant to herbicidesherbicides

Corn-resistant to pestsCorn-resistant to pests

Corn-resistant to Corn-resistant to herbicidesherbicides

Tomatoes- resistant to Tomatoes- resistant to pestspests

Tomatoes-delayed Tomatoes-delayed ripeningripening

Golden rice-beta-Golden rice-beta-carotene added to ricecarotene added to rice

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Conclusions

In this module, you should have learned In this module, you should have learned about;about;

1)The structure, composition and color 1)The structure, composition and color changes of fruits and vegetables.changes of fruits and vegetables.

2)The basic operations of fruit, vegetable and 2)The basic operations of fruit, vegetable and beverage processing.beverage processing.

3)What the terms “organic” and 3)What the terms “organic” and “biotechnology” refer to.“biotechnology” refer to.

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