INGLESE V ANNO

AGRARIA AGROALIMENTARE E

AGROINDUSTRIA

- Carbohydrates / Carboidrati

- Plant Pathology / Malattie delle Piante

- Organic Farming / Coltivazione Biologica

- Olive Oil / Olio d'Oliva

- Weeds / Piante Infestanti

- Harmful Insects / Insetti Nocivi

- Food Preservation / Conservazione del Cibo

- Food Processing / Trasformazione dei Prodotti Alimentari

- Dairy Products / Prodotti Caseari

CARBOHYDRATE

A carbohydrate is a biological molecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water); in other words, with the empirical formula Cm(H2O)n (where m could be different from n). Some exceptions exist; for example, deoxyribose, a sugar component of DNA, has the empirical formula C5H10O4. Carbohydrates are technically hydrates of carbon; structurally it is more accurate to view them as polyhydroxy aldehydes and ketones.

The term is most common in biochemistry, where it is a synonym of saccharide, a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. In general, the monosaccharides and disaccharides, which are smaller (lower molecular weight) carbohydrates, are commonly referred to as sugars. The word saccharide comes from the Greek word σάκχαρον (sákkharon), meaning "sugar". While the scientific nomenclature of carbohydrates is complex, the names of the monosaccharides and disaccharides very often end in the suffix -ose. For example, grape sugar is the monosaccharide glucose, cane sugar is the disaccharide sucrose, and milk sugar is the disaccharide lactose.

Carbohydrates perform numerous roles in living organisms. Polysaccharides serve for the storage of energy (e.g. starch and glycogen) and as structural components (e.g. cellulose in plants and chitin in arthropods). The 5-carbon monosaccharide ribose is an important component of coenzymes (e.g. ATP, FAD and NAD) and the backbone of the genetic molecule known as RNA. The related deoxyribose is a component of DNA. Saccharides and their derivatives include many other important biomolecules that play key roles in the immune system, fertilization, preventing pathogenesis, blood clotting, and development.

In food science and in many informal contexts, the term carbohydrate often means any food that is particularly rich in the complex carbohydrate starch (such as cereals, bread and pasta) or simple carbohydrates, such as sugar (found in candy, jams, and desserts).

Often in lists of nutritional information, such as the USDA National Nutrient Database, the term "carbohydrate" (or "carbohydrate by difference") is used for everything other than water, protein, fat, ash, and ethanol. This will include chemical compounds such as acetic or lactic acid, which are not normally considered carbohydrates. It also includes "dietary fiber" which is a carbohydrate but which does not contribute much in the way of food energy (calories), even though it is often included in the calculation of total food energy just as though it were a sugar.

On the basis of the number of forming units, three major classes of carbohydrates can be defined: monosaccharides, oligosaccharides and polysaccharides.

Monosaccharides or simply sugars are formed by only one polyhydroxy aldehydeidic or ketonic unit.

The most abundant monosaccharide is D-glucose, also called dextrose.

Oligosaccharides are formed by short chains of monosaccharidic units (from 2 to 20) linked one to the next by chemical bounds, called glycosidic bounds. The most abundant oligosaccharides are disaccharides, formed by two monosaccharides, and especially in the human diet the most important are sucrose (common table sugar), lactose and maltose. Within cells many oligosaccharides formed by three or more units do not find themselves as free molecules but linked to other ones, lipids or proteins, to form glycoconjugates.

Polysaccharides are polymers consisting of 20 to 107 monosaccharidic units; they differ each other for the monosaccharides recurring in the structure, for the length and the degree of branching of chains or for the type of links between units.

Whereas in the plant kingdom several types of polysaccharides are present, in vertebrates there are only a small number.

Polysaccharides are defined:

- omopolysaccharides if they contain only one type of monosaccharide as starch, glycogen and chitin;

- eteropolysaccharides, instead, contain two or more different kinds (e.g. hyaluronic acid).

                   

PLANT PATHOLOGY

Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like organisms, phytoplasmas, protozoa, nematodes and parasitic plants. Not included are ectoparasites like insects, mites, vertebrate, or other pests that affect plant health by consumption of plant tissues. Plant pathology also involves the study of pathogen identification, disease etiology, disease cycles, economic impact, plant disease epidemiology, plant disease resistance, how plant diseases affect humans and animals, pathosystem genetics, and management of plant diseases.

Control of plant diseases is crucial to the reliable production of food, and it provides significant reductions in agricultural use of land, water, fuel and other inputs. Plants in both natural and cultivated populations carry inherent disease resistance, but there are numerous examples of devastating plant disease impacts (see Irish potato famine, chestnut blight), as well as recurrent severe plant diseases (see rice blast, soybean cyst nematode, citrus canker). However, disease control is reasonably successful for most crops. Disease control is achieved by use of plants that have been bred for good resistance to many diseases, and by plant cultivation approaches such as crop rotation, use of pathogen-free seed, appropriate planting date and plant density, control of field moisture, and pesticide use. Across large regions and many crop species, it is estimated that diseases typically reduce plant yields by 10% every year in more developed settings, but yield loss to diseases often exceeds 20% in less developed settings. Continuing advances in the science of plant pathology are needed to improve disease control, and to keep up with changes in disease pressure caused by the ongoing evolution and movement of plant pathogens and by changes in agricultural practices. Plant diseases cause major economic losses for farmers worldwide. The Food and Agriculture Organization estimates indeed that pests and diseases are responsible for about 25% of crop loss. To solve this issue, new methods are needed to detect diseases and pests early, such as novel sensors that detect plant odours and spectroscopy and biophotonics that are able to diagnostic plant health and metabolism.

   

Plant pathogens

Fungi

Most phytopathogenic fungi belong to the Ascomycetes and the Basidiomycetes.

The fungi reproduce both sexually and asexually via the production of spores and other structures. Spores may be spread long distances by air or water, or they may be soilborne. Many soil inhabiting fungi are capable of living saprotrophically, carrying out the part of their life cycle in the soil. These are known as facultative saprotrophs.

Fungal diseases may be controlled through the use of fungicides and other agriculture practices. However, new races of fungi often evolve that are resistant to various fungicides.

Biotrophic fungal pathogens colonize living plant tissue and obtain nutrients from living host cells. Necrotrophic fungal pathogens infect and kill host tissue and extract nutrients from the dead host cells.

Bacteria

Most bacteria that are associated with plants are actually saprotrophic and do no harm to the plant itself. However, a small number, around 100 known species, are able to cause disease. Bacterial diseases are much more prevalent in subtropical and tropical regions of the world.

Most plant pathogenic bacteria are rod-shaped (bacilli). In order to be able to colonize the plant they have specific pathogenicity factors. Five main types of bacterial pathogenicity factors are known: uses of cell wall–degrading enzymes, toxins, effector proteins, phytohormones and exopolysaccharides.

Pathogens such as Erwinia species use cell wall–degrading enzymes to cause soft rot. Agrobacterium species change the level of auxins to cause tumours with phytohormones. Exopolysaccharides are produced by bacteria and block xylem vessels, often leading to the death of the plant.

Bacteria control the production of pathogenicity factors via quorum sensing.

Significant abiotic disorders can be caused by:

Natural Drought Frost damage and breakage by snow and hail Flooding and poor drainage Nutrient deficiency

Salt deposition and other soluble mineral excesses (e.g., gypsum) Wind (windburn and breakage by hurricanes and tornadoes) Lightning and wildfire (also often man-made) Man-made (arguably not abiotic, but usually regarded as such) Soil compaction Pollution of air, soil, or both Salt from winter road salt application or irrigation Herbicide over-application Poor education and training of people working with plants (e.g. lawnmower damage to trees) Vandalism.

ORGANIC FARMING

What is Organic Farming ?

Organic farming is a technique, which involves cultivation of plants and rearing of animals in natural ways. This process involves the use of biological materials, avoiding synthetic substances to maintain soil fertility and ecological balance thereby minimizing pollution and wastage. It relies on ecologically balanced agricultural principles like crop rotation, green manure, organic waste, biological pest control, mineral and rock additives. Organic farming make use of pesticides and fertilizers if they are considered natural and avoids the use of various petrochemical fertilizers and pesticides.

International Federation of Organic Agriculture Movements (IFOAM), an international organization established in 1972 for organic farming organizations defines goal of organic farming as:

“Organic agriculture is a production system that sustains the health of soils, ecosystems and people. It relies on ecological processes, biodiversity and cycles adapted to local conditions, rather than the use of inputs with adverse effects. Organic agriculture combines tradition, innovation and science to benefit the shared environment and promote fair relationships and a good quality of life for all involved…”

Need for Organic Farming

The population of the planet is skyrocketing and providing food for the world is becoming extremely difficult. The need of the hour is sustainable cultivation and production of food for all. The Green Revolution and its chemical based technology are losing its appeal as dividends are falling and returns are unsustainable. Pollution and climate change are other negative externalities caused by use of fossil fuel based chemicals. As of 2012, the market for organic farming and other products has reached $63 billion worldwide.

Key features of Organic Farming

• Protecting soil quality using organic material and encouraging biological activity

• Indirect provision of crop nutrients using soil microorganisms • Nitrogen fixation in soils using legumes • Weed and pest control based on methods like crop rotation, biological

diversity, natural predators, organic manures and suitable chemical, thermal and biological intervention

• Rearing of livestock, taking care of housing, nutrition, health, rearing and breeding

• Care for the larger environment and conservation of natural habitats and wild life

Four Principles of Organic Farming

• Principle of Health: Organic agriculture must contribute to the health and well being of soil, plants, animals, humans and the earth. It is the sustenance of mental, physical, ecological and social well being. For instance, it provides pollution and chemical free, nutritious food items for humans.

• Principle of Fairness: Fairness is evident in maintaining equity and justice of the shared planet both among humans and other living beings. Organic farming provides good quality of life and helps in reducing poverty. Natural resources must be judiciously used and preserved for future generations.

• Principle of Ecological Balance: Organic farming must be modeled on living ecological systems. Organic farming methods must fit the ecological balances and cycles in nature.

• Principle of Care: Organic agriculture should be practiced in a careful and responsible manner to benefit the present and future generations and the environment.

As opposed to modern and conventional agricultural methods, organic farming does not depend on synthetic chemicals. It utilizes natural, biological methods to build up soil fertility such as microbial activity boosting plant nutrition.

Secondly, multiple cropping practiced in organic farming boosts bio diversity which enhances productivity and resilience and contributes to a healthy farming system. Conventional farming systems use mono cropping that destroys the soil fertility.

Benefits of Organically Grown Food items and Agricultural Produce

• Better Nutrition: As compared to a longer time conventionally grown food, organic food is much richer in nutrients. Nutritional value of a food item is determined by its mineral and vitamin content. Organic farming enhances the nutrients of the soil which is passed on to the plants and animals.

• Free of poison: Organic farming does not make use of poisonous chemicals, pesticides and weedicides. Studies reveal that a large section of the population fed on toxic substances used in conventional agriculture have fallen prey to diseases like cancer. As organic farming avoids these toxins, it reduces the sickness and diseases due to them.

• Enhanced Taste: The quality of food is also determined by its taste. Organic food often tastes better than other food. The sugar content in organically grown

fruits and vegetables provides them with extra taste. The quality of fruits and vegetables can be measured using Brix analysis.

• Longer shelf–life: Organic plants have greater metabolic and structural integrity in their cellular structure than conventional crops. This enables storage of organic food for a longer time.

Organic farming is preferred as it battles pests and weeds in a non-toxic manner, involves less input costs for cultivation and preserves the ecological balance while promoting biological diversity and protection of the environment.

OLIVE OIL

Olive oil is a fat obtained from the olive (the fruit of Olea europaea; family Oleaceae), a traditional tree crop of the Mediterranean Basin. The oil is produced by pressing whole olives. It is commonly used in cooking, whether for frying or as a salad dressing. It is also used in cosmetics, pharmaceuticals, and soaps, and as a fuel for traditional oil lamps, and finds uses in some religions. It is associated with the Mediterranean diet popularized since the 1950s in North America for its possible health benefits. The olive is one of the three core food plants in Mediterranean cuisine, the other two being wheat and the grape.

Olive trees have been grown around the Mediterranean since the 8th millennium BC. Spain is by far the largest producer of olive oil, followed by Italy and Greece. Per capita consumption is however highest in Greece, followed by Spain, Italy, and Morocco. Consumption in North America and northern Europe is far less, but rising steadily.

The composition of olive oil varies with the cultivar, altitude, time of harvest and extraction process. It consists mainly of oleic acid (up to 83%), with smaller amounts of other fatty acids including linoleic acid (up to 21%) and palmitic acid (up to 20%). Extra-virgin olive oil is required to have no more than 0.8% free acidity and is considered to have the best flavor; it forms as much as 80% of total production in Greece and 65% in Italy, but far less in other countries.

Varieties

There are many different olive varieties or olives, each with a particular flavor, texture, and shelf life that make them more or less suitable for different applications such as direct human consumption on bread or in salads, indirect consumption in domestic cooking or catering, or industrial uses such as animal feed or engineering applications.

Production and consumption

In 2013, world production of virgin olive oil was 2.8 million tonnes (table), a 20% decrease from the 2012 world production of 3.5 million tonnes. Spain produced 1.1 million tonnes or 39% of world production in 2013. 75% of Spain's production derives from the region of Andalucía, particularly within Jaén province which produces 70% of olive oil in Spain. The world’s largest olive oil mill, capable of processing 2,500 tons of olives per day, is in the town of Villacarrillo, Jaén.

Although Italy is a net importer of olive oil, it produced 442,000 tonnes in 2013 or 16% of the world's production (table). Major Italian producers are known as "Città dell'Olio", "oil cities"; including Lucca, Florence and Siena, in Tuscany. The largest

production, however, is harvested in Apulia and Calabria. Greece accounted for 11% of world production in 2013.

Australia now produces a substantial amount of olive oil. Many Australian producers only make premium oils, while a number of corporate growers operate groves of a million trees or more and produce oils for the general market. Australian olive oil is exported to Asia, Europe and the United States.

In North America, Italian and Spanish olive oils are the best-known, and top-quality extra-virgin olive oil from Italy, Spain, Portugal and Greece are sold at high prices, often in prestige packaging. A large part of U.S. olive oil imports come from Italy, Spain, and Turkey.

The United States produces olive oil in California, Arizona, Texas, and Georgia.

Commercial grades

All production begins by transforming the olive fruit into olive paste by crushing or pressing. This paste is then malaxed (slowly churned or mixed) to allow the microscopic oil droplets to agglomerate. The oil is then separated from the watery matter and fruit pulp with the use of a press (traditional method) or centrifugation (modern method). After extraction the remnant solid substance, called pomace, still contains a small quantity of oil.

To classify its organoleptic qualities, olive oil is judged by a panel of trained tasters in a blind taste test.

One parameter used to characterise an oil is its acidity. In this context, "acidity" is not chemical acidity in the sense of pH, but the percent (measured by weight) of free oleic acid. Measured by quantitative analysis, acidity is a measure of the hydrolysis of the oil's triglycerides: as the oil degrades, more fatty acids are freed from the glycerides, increasing the level of free acidity and thereby increasing hydrolytic rancidity. Another measure of the oil's chemical degradation is the peroxide value, which measures the degree to which the oil is oxidized damaged by free radicals, leading to oxidative rancidity. Phenolic acids present in olive oil also add acidic sensory properties to aroma and flavor.

The grades of oil extracted from the olive fruit can be classified as:

• Virgin means the oil was produced by the use of mechanical means only, with no chemical treatment. The term virgin oil with reference to production method includes all grades of virgin olive oil, including Extra Virgin, Virgin, Ordinary

Virgin and Lampante Virgin olive oil products, depending on quality (see below).

• Lampante virgin oil is olive oil extracted by virgin (mechanical) methods but not suitable for human consumption without further refining; lampante is Italian for "glaring", referring to the earlier use of such oil for burning in lamps. Lampante virgin oil can be used for industrial purposes, or refined (see below) to make it edible.

• Refined Olive Oil is the olive oil obtained from any grade of virgin olive oil by refining methods which do not lead to alterations in the initial glyceridic structure. The refining process removes colour, odour and flavour from the olive oil, and leaves behind a very pure form of olive oil that is tasteless, colourless and odourless and extremely low in free fatty acids. Olive oils sold as the grades extra-virgin olive oil and virgin olive oil therefore cannot contain any refined oil.

• Crude Olive Pomace Oil is the oil obtained by treating olive pomace (the leftover paste after the pressing of olives for virgin olive oils) with solvents or other physical treatments, to the exclusion of oils obtained by re-esterification processes and of any mixture with oils of other kinds. It is then further refined into Refined Olive Pomace Oil and once re-blended with virgin olive oils for taste, is then known as Olive Pomace Oil.

WEEDS  

Damages caused by weeds

Weeds are harmful in many ways. The damages caused by them are as under:

1. Reduction in crop yield:- Weeds compete with crops for water, nutrients and light. Being hardy and vigorous in growth habit, they grow faster then crops and consume large amount of water and nutrients, thus causing heavy losses in yields.

2. Increase in the cost of cultivation:- Tillage operations are done to control weeds and it is generally estimated that on an average about 30 percent of the total expenditure for crop production is on tillage operations and more labour is employed for weeding. This results in increasing cost of cultivation and reducing the margin of net profit.

3. The quality of field produce is reduced:- When the crop is harvested from a weedy field the seeds of weeds get mixed with the main crop which results in lowering the quality of the produce .e.g. seeds of weeds in wheat, gram etc. Similarly, bundles of many leafy vegetables like methi or palak contain green plants of weeds. They fetch lower prices in the market.

4. The quality of the livestock products is reduced. Certain weeds eg. Hulhul when eaten by milch cattle impart an undesirable flavour to milk. Similarly weeds like gokhru get attached to the body of the sheep and impair the quality of wool. Certain poisonous weeds like Datura may cause death of cattle if they are unknowingly eaten by cattle.

5. Weeds harbour insect, pests and diseases:- Weeds either give shelter to various insects, pests and diseases or serve as alternate hosts.

6. Weeds check the flow of water:- Weeds block drainage and check the flow of water in irrigation channels and field channels thereby increasing the seepage losses as well as losses through overflowing. The irrigation efficiency is also reduced.

7. Weed secretions are harmful:- Heavy growth of certain weeds like quack grass or motha lower the germination and reduce the growth of many crop plants. This is said to be due to the presence of certain phytotoxins in these weeds.

8. Weeds are harmful to human beings:- certain weeds cause irritation of skin, allergy and poisoning in human beings.

9. Weeds cause quicker wear and tear of farm implements; they get worn out early and cannot work efficiently unless they are properly sharpened or mended.

10. Weeds reduce the value of the land:- Agricultural lands which are heavily infested with perennial weeds like kans always fetch less price, because such lands can not be brought under cultivation without incurring heavy expenditure on labour and machinery.

Weed control Methods

Before adopting an appropriate method for effective control of weeds, it is essential to know about the weed seeds dispersal, mode of propagation, crop-weed competition. Nature has provided weeds either a number of devices that help them to be disseminated widely. The agents which help the dispersal of weed seeds far and wide are water, wind and animals including man. Other means are impure seeds, sewage, sludge, organic manures, agricultural implements, birds, drainage water. The weed control methods can be broadly classified as preventive and control methods. Preventive measures include all such measures through which the introduction of weeds into the crop fields could be avoided. Control methods include ways of their control and eradication after they have grown in the crop field.

Preventive Measures

Since weeds multiply at a much faster rate and are hardier than crop plants, they always have an upper hand if they are allowed to establish in the field. Therefore, it is difficult and costly to eradicate them. The preventive measures are: i) Use clean seeds which free from weed seeds. ii) Use-well decomposed cow-dung or compost. iii) Cut weeds before seeding. iv) Remove weed growth.

Control Methods

They are classified as: 1. Mechanical methods 2. Cropping or cultural methods 3. Biological methods 4. Chemicals methods

1. Mechanical Method

The most common ones are hand pulling, hand weeding, burning, flooding, ploughing, and harrowing etc. Pulling the weeds by hand or with the help of sickle is the oldest and most efficient method. Weeds can be easily uprooted after a good soaking irrigation or rain. This method is costly and time consuming.

2. Cropping or cultural methods

These include proper crop rotations so that neither annual nor perennial weeds have a free growth. Continuous cropping with the same cropping system leads to greater

infestation of fallow helps in controlling the weeds effectively. Intertilled crops like cotton and crops like potato / groundnut which necessarily require digging of soil help in reducing the infestation of weeds. Growing crops like sannhemp which have a very vigorous and leafy growth help in smothering the weeds. A suitable combination of mechanical methods and crop rotation is very effective method of weed control.

3. Biological Methods of weed control

Plant or animal enemies of the weeds maybe used for their destruction. The most notable example is control of prickly pear by using cochineal insects. The Kans grass is controlled by growing basket grass, the roots of which are supposed to excrete substances inhibitory to Kans. Presently, the biological control of weed is including the use of plant pathogens, nematodes, parasitic plants and other organisms. Biological methods have been found to be very efficient and economical provided right type of predators, which even under starvation conditions will not feed upon cultivated crop are found out and introduced.

4. Chemical method of weed control

Any chemical that kills the plants or inhibits their growth is known as herbicide and the method of its application is called chemical method of weed control. Such chemicals may be classified as:) selective herbicides, and ii) Non-Selective herbicides. Each group is further divided into two groups viz. foliage applied herbicides are again grouped into two categories viz. contact & Tran located herbicides. Non-selective herbicides are those chemicals which kill the entire vegetation of the treated area and hence they are applied only on waste lands like canal banks, roadsides etc. Selective herbicides:- such chemicals kill only those plants for whom they have selectivity. They are as under:

A) Foliage applied herbicides:

These chemical are applied over the leaves or green foliage. They are: a) Contact herbicides: - They kill the plant parts which come in contact with the applied chemical. Weed killing efficiency depends upon their concentration, uniformity in coverage of spraying, stage of weed, weather conditions eg. Dicryl, potassium cynate, sodium arsenite. b) Translocated herbicides:- Such chemicals are absorbed by the treated foliage. When sprayed, they are translocated to the roots which are later destroyed. These are best for perennial weeds. They are also known as systemic herbicides eg. 2-4 D.

B) Soil applied herbicides:

They are used to keep the field completely free from plant growth. a) Soil fumigants:- They form vapour or gas and diffuse through soils. When applied, they kill all the plant growth. They have relatively short stability of few weeks after which the crop

seed may be sown or planted in the treated field eg. Carbon-disulphide, methyl bromide. b) Soil Sterilants:- Such chemicals sterilize the soil and make it unfit for any vegetation for varying period of time depending on the nature and dose of the chemical used, soil type, organic matter content of the soil, rainfall etc. eg. Simazine and Atrazine.

C) Aquatic Applications:

Such chemicals are used by dissolving or emulsifying in water bodies viz canals, ditches, ponds, lakes etc. to control submerged aquatic weeds. eg. Aqualin, Endothal. Methods of herbicide application i) Pre-sowing treatment:- Application of herbicide before sowing or planting of the crop. ii) Pre-emergence treatment:- In this method, the herbicide is applied after sowing or planting of the crop but before the emergence of the crop. iii) Post emergence treatment:- In this method herbicide is applied after full emergence of crop plants. iv) Directed application:- In widely spaced row crop, the herbicides are sprayed over the space left between the rows without treating the crop foliage or crop shoots. Non selective herbicides are applied in this method. v) Band application:- In this method the herbicides are sprayed only over the crop rows and the inter row spaces can be given. Mechanical treatment. This method is adopted for expensive herbicides, which may not be used for overall application due to high costs. Normally soil applied herbicides are applied in this case.

HARMFUL INSECTS    

Insects considered pests of some sort occur among all major living orders with the exception of Ephemeroptera (mayflies), Odonata, Plecoptera (stoneflies), Embioptera (webspinners), Trichoptera (caddisflies), Neuroptera (in the broad sense), and Mecoptera (also, the tiny groups Zoraptera, Grylloblattodea, and Mantophasmatodea). Conversely, of course, essentially all insect orders primarily have members which are beneficial, in some respects, with the exception of Phthiraptera (lice), Siphonaptera (fleas), and Strepsiptera, the three orders whose members are exclusively parasitic.

Insects are considered as pests for a variety of reasons including their

• direct damage by feeding on crop plants in the field or by infesting stored products

• indirect damage by spreading viral diseases of crop plants (especially by sucking insects such as leafhoppers)

• spreading disease among humans and livestock • annoyance to humans

Examples

• The Phylloxera plague

• Migratory locust • Colorado potato beetle • Boll weevil • Japanese beetle • Aphids • Mosquitoes • Cockroach • Western corn rootworm • Some fly species

In the past entomologists working on pest insects attempted to eradicate species. This has rarely worked except in islands or controlled environments and raises ethical issues. Over time the language has changed to terms like control and management. The indiscriminate use of toxic and persistent chemicals and the resurgence of pests in the history of cotton growing in the US has been particularly well studied.

Beneficial insects

Honey is perhaps the most economically valuable product from insects. Apiculture is a commercial enterprise in most parts of the world and many forest tribes have been dependent on honey as a major source of nutrition. Honeybees can also act as pollinators of crop species. Many predators and parasitoid insects are encouraged and augmented in modern agriculture.

Silk is extracted from both reared caterpillars as well as from the wild (producing wild silk). Sericulture deals with the techniques for efficient silkworm rearing and silk production. Although new fabric materials have substituted silk in many applications, it continues to be the material of choice for surgical sutures.

Lac was once extracted from scale insects but is now replaced by synthetic substitutes. The dye extracted from cochineal insects was similarly replaced by technological advances.

The idea of insects as human food, entomophagy, has been proposed as a solution to meet the growing demand for food, but has not gained widespread acceptance.

FOOD PRESERVATION

Food preservation involves preventing the growth of bacteria, fungi (such as yeasts), or other micro-organisms (although some methods work by introducing benign bacteria or fungi to the food), as well as slowing the oxidation of fats that cause rancidity. Food preservation may also include processes that inhibit visual deterioration, such as the enzymatic browning reaction in apples after they are cut during food preparation.

Many processes designed to preserve food will involve a number of food preservation methods. Preserving fruit by turning it into jam, for example, involves boiling (to reduce the fruit’s moisture content and to kill bacteria, etc.), sugaring (to prevent their re-growth) and sealing within an airtight jar (to prevent recontamination). Some traditional methods of preserving food have been shown to have a lower energy input and carbon footprint, when compared to modern methods.

Some methods of food preservation are known to create carcinogens. In 2015, the International Agency for Research on Cancer of the World Health Organization classified processed meat, i.e. meat that has undergone salting, curing, fermenting, and smoking, as "carcinogenic to humans".

Maintaining or creating nutritional value, texture and flavor is an important aspect of food preservation, although, historically, some methods drastically altered the character of the food being preserved. In many cases these changes have come to be seen as desirable qualities – cheese, yogurt and pickled onions being common examples.

Traditional techniques

New techniques of food preservation became available to the home chef from the dawn of agriculture until the Industrial Revolution.

Drying

Drying is one of the oldest techniques used to hamper the decomposition of food products. As early as 12,000 B.C., Middle Eastern and Oriental cultures were drying foods using the power of the sun. Vegetables and fruits are naturally dried by the sun and wind, but "still houses" were built in areas that did not have enough sunlight to dry things. A fire would be built inside the building to provide the heat to dry the various fruits, vegetables, and herbs.

Cooling

Cooling preserves food by slowing down the growth and reproduction of micro-organisms and the action of enzymes that cause food to rot. The introduction of commercial and domestic refrigerators drastically improved the diets of many in the Western world by allowing foods such as fresh fruit, salads and dairy products to be stored safely for longer periods, particularly during warm weather.

Freezing

Freezing is also one of the most commonly used processes, both commercially and domestically, for preserving a very wide range of foods, including prepared foods that would not have required freezing in their unprepared state. For example, potato waffles are stored in the freezer, but potatoes themselves require only a cool dark place to ensure many months' storage. Cold stores provide large-volume, long-term storage for strategic food stocks held in case of national emergency in many countries.

Boiling

Boiling liquid food items can kill any existing microbes. Milk and water are often boiled to kill any harmful microbes that may be present in them.

Heating

Heating to temperatures which are sufficient to kill microorganisms inside the food is a method used with perpetual stews. Milk is also boiled before storing to kill many microorganisms.

Salting

Salting or curing draws moisture from a substance through a process of osmosis. substances are cured with salt or sugar, or a combination of the two. Nitrates and nitrites are also often used to cure meat and contribute the characteristic pink colour. It was a main method of preservation in medieval times and around the 1700s.

Sugaring

The earliest cultures have used sugar as a preservative, and it was commonplace to store fruit in honey. Similar to pickled foods, sugar cane was brought to Europe through the trade routes. In northern climates without sufficient sun to dry foods, preserves are made by heating the fruit with sugar. "Sugar tends to draw water from the microbes (plasmolysis). This process leaves the microbial cells dehydrated, thus killing them. In this way, the food will remain safe from microbial spoilage." Sugar is used to preserve fruits, either in an anti-microbial syrup with fruit such as apples,

pears, peaches, apricots and plums, or in crystallized form where the preserved material is cooked in sugar to the point of crystallization and the resultant product is then stored dry. This method is used for the skins of citrus fruit (candied peel), angelica and ginger. Also sugaring can be used in jam jellies.

Smoking

Smoking is used to lengthen the shelf life of perishable food items. This effect is achieved by exposing the food to smoke from burning plant materials such as wood. Smoke deposits a number of pyrolysis products onto the food, including the phenols syringol, guaiacol and catechol. These compounds aid in the drying and preservation of meats and other foods. Most commonly subjected to this method of food preservation are meats and fish that have undergone curing. Fruits and vegetables like paprika, cheeses, spices, and ingredients for making drinks such as malt and tea leaves are also smoked, but mainly for cooking or flavoring them. It is one of the oldest food preservation methods, which probably arose after the development of cooking with fire.

Pickling

Pickling is a method of preserving food in an edible anti-microbial liquid. Pickling can be broadly classified into two categories: chemical pickling and fermentation pickling.

In chemical pickling, the food is placed in an edible liquid that inhibits or kills bacteria and other micro-organisms. Typical pickling agents include brine (high in salt), vinegar, alcohol, and vegetable oil, especially olive oil but also many other oils. Many chemical pickling processes also involve heating or boiling so that the food being preserved becomes saturated with the pickling agent. Common chemically pickled foods include cucumbers, peppers, corned beef, herring, and eggs, as well as mixed vegetables such as piccalilli.

In fermentation pickling, the food itself produces the preservation agent, typically by a process that produces lactic acid. Fermented pickles include sauerkraut, nukazuke, kimchi, surströmming.

Industrial/modern techniques

Techniques of food preservation were developed in research laboratories for commercial applications.

Pasteurization

Pasteurization is a process for preservation of liquid food. It was originally applied to combat the souring of young local wines. Today, the process is mainly applied to

dairy products. In this method, milk is heated at about 70 °C for 15 to 30 seconds to kill the bacteria present in it and cooling it quickly to 10 °C to prevent the remaining bacteria from growing. The milk is then stored in sterilized bottles or pouches in cold places. This method was invented by Louis Pasteur, a French chemist, in 1862.

Vacuum packing

Vacuum-packing stores food in a vacuum environment, usually in an air-tight bag or bottle. The vacuum environment strips bacteria of oxygen needed for survival. Vacuum-packing is commonly used for storing nuts to reduce loss of flavor from oxidization. A major drawback to vacuum packaging, at the consumer level, is that vacuum sealing can deform contents and rob certain foods, such as cheese, of its flavor.

Artificial food additives

Preservative food additives can be antimicrobial, which inhibit the growth of bacteria or fungi, including mold, or antioxidant, such as oxygen absorbers, which inhibit the oxidation of food constituents. Common antimicrobial preservatives include calcium propionate, sodium nitrate, sodium nitrite, sulfites (sulfur dioxide, sodium bisulfite, potassium hydrogen sulfite, etc.) and disodium EDTA. Antioxidants include BHA and BHT. Other preservatives include formaldehyde (usually in solution), glutaraldehyde (kills insects), ethanol, and methylchloroisothiazolinone.

Modified atmosphere

Modifying atmosphere is a way to preserve food by operating on the atmosphere around it. Salad crops that are notoriously difficult to preserve are now being packaged in sealed bags with an atmosphere modified to reduce the oxygen (O2) concentration and increase the carbon dioxide (CO2) concentration. There is concern that, although salad vegetables retain their appearance and texture in such conditions, this method of preservation may not retain nutrients, especially vitamins. There are two methods for preserving grains with carbon dioxide. One method is placing a block of dry ice in the bottom and filling the can with the grain. Another method is purging the container from the bottom by gaseous carbon dioxide from a cylinder or bulk supply vessel. Carbon dioxide prevents insects and, depending on concentration, mold and oxidation from damaging the grain. Grain stored in this way can remain edible for approximately five years.

Nitrogen gas (N2) at concentrations of 98% or higher is also used effectively to kill insects in the grain through hypoxia. However, carbon dioxide has an advantage in this respect, as it kills organisms through hypercarbia and hypoxia (depending on concentration), but it requires concentrations of above 35%, or so. This makes carbon dioxide preferable for fumigation in situations where a hermetic seal cannot be maintained.

FOOD PROCESSING

Food processing is the transformation of raw ingredients, by physical or chemical means into food, or of food into other forms. Food processing combines raw food ingredients to produce marketable food products that can be easily prepared and served by the consumer. Food processing typically involves activities such as mincing and macerating, liquefaction, emulsification, and cooking (such as boiling, broiling, frying, or grilling); pickling, pasteurization, and many other kinds of preservation; and canning or other packaging. (Primary-processing such as dicing or slicing, freezing or drying when leading to secondary products are also included.)

Benefits

Benefits of food processing include toxin removal, preservation, easing marketing and distribution tasks, and increasing food consistency. In addition, it increases yearly availability of many foods, enables transportation of delicate perishable foods across long distances and makes many kinds of foods safe to eat by de-activating spoilage and pathogenic micro-organisms. Modern supermarkets would not exist without modern food processing techniques, and long voyages would not be possible.

Processed foods are usually less susceptible to early spoilage than fresh foods and are better suited for long distance transportation from the source to the consumer. When they were first introduced, some processed foods helped to alleviate food shortages and improved the overall nutrition of populations as it made many new foods available to the masses.

Processing can also reduce the incidence of food borne disease. Fresh materials, such as fresh produce and raw meats, are more likely to harbour pathogenic micro-organisms (e.g. Salmonella) capable of causing serious illnesses.

The extremely varied modern diet is only truly possible on a wide scale because of food processing. Transportation of more exotic foods, as well as the elimination of much hard labour gives the modern eater easy access to a wide variety of food unimaginable to their ancestors.

The act of processing can often improve the taste of food significantly.

Mass production of food is much cheaper overall than individual production of meals from raw ingredients. Therefore, a large profit potential exists for the manufacturers and suppliers of processed food products. Individuals may see a benefit in convenience, but rarely see any direct financial cost benefit in using processed food as compared to home preparation.

Processed food freed people from the large amount of time involved in preparing and cooking "natural" unprocessed foods. The increase in free time allows people much more choice in life style than previously allowed. In many families the adults are working away from home and therefore there is little time for the preparation of food based on fresh ingredients. The food industry offers products that fulfill many different needs: e.g. fully prepared ready meals that can be heated up in the microwave oven within a few minutes.

Modern food processing also improves the quality of life for people with allergies, diabetics, and other people who cannot consume some common food elements. Food processing can also add extra nutrients such as vitamins.

Drawbacks

Any processing of food can affect its nutritional density. The amount of nutrients lost depends on the food and processing method. For example, heat destroys vitamin C. Therefore, canned fruits possess less vitamin C than their fresh alternatives. The USDA conducted a study in 2004, creating a nutrient retention table for several foods.

New research highlighting the importance to human health of a rich microbial environment in the intestine indicates that abundant food processing (not fermentation of foods) endangers that environment.

Using food additives represents another safety concern. The health risks of any given additive vary greatly from person to person; for example using sugar as an additive endangers diabetics. In the European Union, only European Food Safety Authority (EFSA) approved food additives (e.g., sweeteners, preservatives, stabilizers) are permitted at specified levels for use in food products. Approved additives receive an E number (E for Europe), simplifying communication about food additives included in the ingredients' list for all the different languages spoken in the EU. As effects of chemical additives are learnt, changes to laws and regulatory practices are made to make such processed foods more safe.

Food processing is typically a mechanical process that utilizes large mixing, grinding, chopping and emulsifying equipment in the production process. These processes inherently introduce a number of contamination risks. As a mixing bowl or grinder is used over time the food contact parts will tend to fail and fracture. This type of failure will introduce into the product stream small to large metal contaminants. Further processing of these metal fragments will result in downstream equipment failure and the risk of ingestion by the consumer. Food manufacturers utilize industrial metal detectors to detect and reject automatically any metal fragment. Large food processors will utilize many metal detectors within the processing stream to reduce both damage to processing machinery as well as risk to consumer health.

DAIRY PRODUCTS

Dairy products or milk products are food produced from the milk of mammals, primarily cattle, water buffaloes, goats, sheep, and camels. A facility that processes milk into items like yogurt or cheese is a dairy or dairy factory. Dairy products are widely consumed worldwide, except for most of East and Southeast Asia and parts of central Africa.

Types of dairy products

• Milk after optional homogenization, pasteurization, in several grades after standardization of the fat level, and possible addition of the bacteria Streptococcus lactis and Leuconostoc citrovorum

o Crème fraîche, slightly fermented cream § Clotted cream, thick, spoonable cream made by heating milk § Single cream, double cream and whipping cream § Smetana, Central and Eastern European variety of sour cream

o Cultured milk resembling buttermilk, but uses different yeast and bacterial cultures

o Kefir, fermented milk drink from the Northern Caucasus o Kumis/Airag, slightly fermented mares' milk popular in Central Asia o Powdered milk (or milk powder), produced by removing the water from

(usually skim) milk § Whole milk products § Buttermilk products § Skim milk § Whey products § High milk-fat and nutritional products (for infant formulas) § Cultured and confectionery products

o Condensed milk, milk which has been concentrated by evaporation, with sugar added for reduced process time and longer life in an opened can

o Khoa, milk which has been completely concentrated by evaporation, used in Indian cuisine including gulab jamun, peda, etc.)

o Evaporated milk, (less concentrated than condensed) milk without added sugar

o Ricotta, acidified whey, reduced in volume o Infant formula, dried milk powder with specific additives for feeding

human infants o Baked milk, a variety of boiled milk that has been particularly popular in

Russia • Butter, mostly milk fat, produced by churning cream

o Buttermilk, the liquid left over after producing butter from cream, often dried as livestock feed

o Ghee, clarified butter, by gentle heating of butter and removal of the solid matter

o Smen, a fermented, clarified butter used in Moroccan cooking o Anhydrous milkfat (clarified butter)

• Cheese, produced by coagulating milk, separating from whey and letting it ripen, generally with bacteria and sometimes also with certain molds

o Curds, the soft, curdled part of milk (or skim milk) used to make cheese o Paneer o Whey, the liquid drained from curds and used for further processing or

as a livestock feed o Cottage cheese o Quark o Cream cheese, produced by the addition of cream to milk and then

curdled to form a rich curd or cheese o Fromage frais

• Casein are o Caseinates, sodium or calcium salts of casein o Milk protein concentrates and isolates o Whey protein concentrates and isolates, reduced lactose whey o Hydrolysates, milk treated with proteolytic enzymes to alter

functionality o Mineral concentrates, byproduct of demineralizing whey

• Yogurt, milk fermented by Streptococcus salivarius ssp. thermophilus and Lactobacillus delbrueckii ssp. bulgaricus sometimes with additional bacteria, such as Lactobacillus acidophilus

Health

Dairy products can cause health issues for individuals who have lactose intolerance or a milk allergy.

Additionally dairy products including cheese, ice cream, milk, butter, and yogurt can contribute significant amounts of cholesterol and saturated fat to the diet. Diets high in fat and especially in saturated fat can increase the risk of heart disease and can cause other serious health problems. However, it has been shown that there is no connection between dairy consumption (excluding butter) and cardiovascular disease, even though dairy tends to be higher in saturated fats.