Food packaging draws on disciplines like chemistry, microbiology, food science and engineering. About 25% of the ex-factory cost is for packaging and thus provides the challenge for food packaging technologists to design and develop functional packages at low cost. Today packaging is pervasive and essential. It surrounds, enhances and protects the goods from processing and manufacturing through handing and storage to final consumption without packing, materials would be messy and modern consumer marketing would not be possible.
The inter disciplinary nature of food packaging needs to be understood for some it is best but for most it is waste of resources and environmental menace. Packaging is an industrial and marketing technique for airing, protecting, identifying and facilitating the sale and distribution of agricultural, industrial and consumer products. The Packaging Institute International defines packaging as the enclosure of products items or packages in a wrapped pouch, big-box, cup, tray, can, tube, bottle or other container to protect & preserve.
UK Institute of packaging defines packaging as 1. A coordinated system of preparing foods for transport, distribution, storage, retailing and end use. 2. A means of ensuring safe delivery to the ultimate consumer in sound condition at minimum cost. 3. A techno-economic function aimed at minimizing costs of delivery while maximinsing sales (and hence profits) Primary packaging is one which is in direct contact with contained product. It provides the initial and usually the major protective barrier e. g. metal cans, plastic pouches, glass bottles. Secondary contains a no. f primary packages e. g. a corrugated case. It is the physical distribution carrier. Terliary package is made up of number of secondary packages, e. g. stretch wrapped pallet. Change of food packaging materials: Food packaging materials play a primary role in protecting the contents from ultra violet rays, germs in air, shocks during transportation etc. while they turn into waste after consumption of non-industrial waste which comprises primilary of household garbage, waste packaging materials account for 60% of total volume and 20 – 30 % of total weight.
They need to be collected and treated separately as they are usually made of several materials, a factor that makes the recycling of packaging material rather difficult. Companies for this reason changed the packaging materials for frozen foods in 2002, composite materials (nylon or aluminized polypropylene) to polypropylene. New packaging materials, when incinerated produce less CO2 and hazardous gases. Food companies provide products which are eco-friendly. Recycle plaza JB (located in Japan) treats 64 tonnes of used container a day.
Paying attention to the environment as critical theme that should be addressed to not only by the companies but also each individual. Everyday our lives are touched by plastic packaging products. PET (Polyethylene Terphthalate) Used in beverage containers, food containers, boil in food pouches processed meat packages etc. It is popular for making bottles for cokes & fizzy drinks as PET is more impermeable than other low cost plastics. HDPE (High density polyethylene) HDPE (High density polyethylene) is used in milk bottles, cereal box liners, detergent bottles, oil bottles, margarine tubs, toys, plastic bags etc.
PVC (Polyvinyl Chloride) used in food wrap, vegetable oil bottles and blister packaging. LDPE (Low density polyethylene) used in shrink wrap, plastic bags, garment bags, dry cleaning bags and squeezable food bottles. PP (Polypropylene) used in margarine and yogurt containers, cops for containers, wrapping to replace cellophone, medicine bottles etc. PS (Polystrene) used in egg, fast food trays disposable plastic silver ware, cups, compact disc jackets. Plastics in the Environment:
There is a growing awareness of the health and environmental consequences of food packaging, especially plastic packaging made from petroleum products. Reduction of the use of packaged and throw away items seems the right course. Consumers have to take responsibility for their own personal choices, by choosing more sustain products, and by choosing to use fewer packaged products. Polyvinyl Chloride: PVC is the toxic plastic and poses risk to both Human Health and environment. PVC is least recyclable plastic. 1. Vinyl chloride workers have alleviated risk of liver cancer. 2. V. C. auses water and air pollution. 3. PVC needs additives which contribute to pollution and human exposure. FOOD TECHNOLOGY Food Technology, or food tech in short is the application of food science to selection, preservation, processing, packaging, distribution and use of safe nutritious and wholesome food. Food scientists and Food technologists study the physical (1), microbiological and chemical makeup of food. Depending on their area of specialization, food scientists may develop ways to process, preserve, package or store food, according to industry and government specifications and regulations.
Consumers seldom think of the vast array of foods and the research and development that has resulted in the means to deliver tasty, nutritious, safe and convenient foods. In some schools, food technology is part of the curriculum and teaches, alongside cooking, nutrition and the food and also educate them about manufacturing process. EARLY HISTORY OF FOOD TECHNOLOGY Research in the field now known as food technology has been conducted for decades. Nicolas Appert’s development in 1810 of the canning process was as decisive event.
The process wasn’t called canning then and Appert did not really know the principle on which his process worked but -canning has had a major impact on food preservation techniques. Louis Pasteur’s research on the spoilage of wine and his description of how to avoid spoilage in 1864 was an early attempt to put food technology on a scientific basis. Besides research into wine spoilage, Pasteur did research on the production of alcohol, vinegar Wines and beer, and the souring of milk. He developed pasteurization- the process of heating milk and milk products to destroy food spoilage and disease-producing organisms.
In his research into food technology Pasteur became the pioneer into bacteriology and of modern preventive medicine. DEVELOPMENTS IN FOOD TECHNOLOGY Some of the developments that have contributed greatly to the food supply are: Instantized milk powder- D. D. peebles developed the first instant milk powder which has become the basis for q variety of new products that are rehydratable in cold water or milk. This process increases the surface area pf the powdered, product by partially rehydrating spray-dried milk powder.
Freeze drying- the first application of freeze drying was most likely in the pharmaceutical industry; however a successful large- scale industrial application of the process was the development of continuous freeze drying of coffee. High temperature Short Time Processing- These processes for the most part are characterized by rapid heating and cooling, holding for a short time at a relatively high temperature and filling aseptically into sterile containers. Decaffeination of coffee and tea was first developed on a “commercial basis in Europe around 1900.
The process is described in U. S. patent 897, 763. Green coffee beans are treated with steam or water to around 20% moisture. The added water and heat separate the caffeine from the bean to its surface. Solvents are then used to remove the caffeine from the beans. Process Optimization- Food Technology now allows production of foods to be more efficient, oil saving technologies are now available on different forms. Production methods and methodology have also become increasingly sophisticated. Iqra Ahad. B. Sc. II. Year FOOD PRESERVATION
Food preservation is the process of treating and handling food to stop or greatly slow down spoilage (loss of quality, edibility or nutritive value) caused or accelerated by micro-organisms. Some methods, however, use benign bacteria, yeasts or fungi to add specific qualities and to preserve food (e. g. , cheese, wine). While maintaining or creating nutritional value, texture and flavour is important in preserving its value as food. This is culturally dependent, as what qualifies food fit for humans in one culture may not qualify in another culture.
Preservation usually involves preventing the growth of bacteria, fungi, and other micro-organisms, as well as retarding the oxidation of fats which cause rancidity. It also includes processes to inhibit natural ageing and discolouration that can occur during food preparation such as the enzymatic browning reaction in apples which causes browning when apples are cut. Some preservation methods require the food to be sealed after treatment to prevent recontamination with microbes; others, such as drying, allow food to be stored without any special containment for long periods.
Common methods of applying these processes include drying, spray drying, freeze drying, freezing, vacuum-packing, canning, preserving in syrup, sugar crystallisation, food irradiation, and adding preservatives or inert gases such as carbon -dioxide. Other methods that not only help to preserve food, but also add flavour, include pickling, salting, smoking, preserving in syrup or alcohol, sugar crystallisation and curing. Preservation Processes MethodEffect on microbial growth or survival
RefrigerationLow temperature to retard growth FreezingLow temperature and reduction of water activity to prevent microbial growth, slowing of oxidation reactions Drying, curing and conservingReduction in water activity sufficient to delay or prevent microbial growth Vacuum and oxygen free modified atmosphere packagingLow oxygen tension inhibits strict aerobes and delays growth of facultative anaerobes Carbon dioxide enriched modified atmosphere packagingSpecific inhibition of some microorganisms Addition of weak acids; e. g. odium lactateReduction of the intracellular pH of, micro-organisms Lactic fermentationReduction of pH value in situ by microbial action and sometimes additional inhibition by the lactic and acetic acids formed and by other microbial products. (e. g. ethanol, bacteriocins) Sugar preservationCooking in high sucrose concentration creating too high osmotic pressure for most microbial survival Ethanol preservationSteeping or cooking in Ethanol produces toxic inhibition of microbes. Can be combined with sugar preservation Carbon dioxide enriched modified atmosphere packagingLow temperature to retard growth EmulsificationCompartmentalization and utrient limitation within the aqueous droplets in Water-in-oil emulsion foods Addition of preservatives such as nitrite or sulphite ionsInhibition of specific groups of micro- organisms Pasteurization and appertizationDelivery of heat sufficient to inactivate target microorganisms to the desired extent Food irradiation (Radurization, rededication and radappertization)Delivery of ionizing radiation to disrupt cellular RNA Application of high hydrostatic pressure (Pascalization)Pressure-inactivation of vegetative bacteria, yeasts and moulds Pulsed electric field processing(PEF treatment)Short bursts of electricity for microbial inactivation Preservation processes include: •Heating to kill or denature organisms (e,g. boiling) •Oxidation (e. g. use of sulphur dioxide) •Toxic inhibition (e. g. smoking, use of carbon dioxide, vinegar, alcohol etc) •Dehydration (drying) •Osmotic inhibition ( e. g. use of syrups) •Low temperature inactivation (e. g. freezing) •Ultra high water pressure (e. g. fresherized, a kind of “cold” pasteurization, the pressure kills naturally occurring pathogens, which cause food deterioration and affect food safety. •Many combinations of these methods •Chelation Drying One of the oldest methods of food preservation is by drying, which reduces water activity sufficiently to prevent or delay bacterial growth. Drying also reduces weight, making food more portable. Most types of meat can be dried; a good example is beef jerky. Many fruits can also be dried; for example, the process is often applied to apples, pears, bananas, mangoes, papaya, apricot, and coconut. Zante currants, sultanas and raisins are all forms of dried grapes. Drying is also the normal means of preservation for cereal grains such as wheat, maize, oats, barley, rice, millet and rye. Freezing
Freezing is also one of the most commonly used processes commercially and domestically for preserving a very wide range of food including prepared food stuffs which 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. 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, slowing spoiling.
Vacuum-packing is commonly used for storing nuts to reduce loss of flavor from oxidation. Salting Salting or curing draws moisture from the meat through a process of osmosis. Meat is 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 color, as well as inhibition of Clostridium botulinum. Smoking Meat, fish and some other foods may be both preserved and flavored through the use of smoke, typically in a smokehouse. The combination of heat to dry the food without cooking it, and the addition of the aromatic (phenolic )hydrocarbons from the smoke preserves the food. Sugar
Sugar is used to preserve fruits, either in syrup with fruit such as apples, pears, peaches, apricots, plums or in crystallized form where the preserved material is cooked in sugar to the point of crystallisation and the resultant product is then stored dry. This method is used for the skins of citrus fruit (qandied peel), angelica and ginger. A modification of this process produces glace fruit such as glace cherries where the fruit is preserved in sugar but is then extracted from the syrup and sold, the preservation being maintained by the sugar content of the fruit and the superficial coating of syrup. The use of sugar is often combined with alcohol for preservation of luxury products such as fruit in brandy or other spirits.
These should not be confused with fruit flavored spirits such as cherry brandy or Sloe gin. Pickling Pickling is a method of preserving food in an edible anti-microbial liquid. Pickling can be broadly categorized -as chemical pickling (for example, brining) and fermentation pickling (for example, making sauerkraut). 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 mixed vegetables such as piccalilli, chow-chow, giardiniera, and achar. In fermentation pickling, the food itself produces the preservation agent, typically by a process that produces lactic acid. Fermented pickles include sauerkraut, nukazuke, kimchi, surstromming, and curtido. Some chemically pickled cucumbers are also fermented. In commercialpickles, a preservative like sodium benzoate or EDT A may also be added to enhance shelf life. Lye Sodium hydroxide (lye) makes food too alkaline for bacterial growth. Lye will saponify fats in the food, which ‘will change its flavor and texture. Lutefisk uses lye in its preparation, as do some olive recipes. Modem recipes for century eggs also call for lye.
Masa harina and hominy use lye in their preparation, but not for preservation. Canning and bottling Canning involves cooking food, sealing it in sterile cans or jars, and boiling the containers to kill or weaken any remaining bacteria as a form of sterilization. Various foods have varying degrees of natural protection against spoilage and may require that the final step occur in a pressure cooker. High-acid fruits like strawberries require no preservatives to can and only a short boiling cycle, whereas marginal fruits such as tomato esrequire longer boiling and addition of other acidic elements. Low acid foods, such as vegetables and meats require pressure canning.
Food preserved by canning or bottling is at immediate risk of spoilage once the can or bottle has been opened. Lack of quality control in the canning process may allow ingress of water or micro-organisms. Most such failures are rapidly detected as decomposition within the can causes gas production and the can will swell or burst. However, there have been examples of poor manufacture (under processing)and poor hygiene allowing contamination of canned food by the obligate anaerobe, Clostridium botulinum which produces an acute toxin within the food, leading to severe illness or death. This organism produces no gas or obvious taste and remains undetected by taste or smell.
Its toxin is denatured by cooking, though. Cooked mushrooms, handled poorly and then canned, can support the growth of Staphylococcus aureus, which produces a toxin that is not destroyed by canning or subsequent reheating. Jellying Food may be preserved by cooking in a material that solidifies to form a gel. Such materials include gelatine, agar, maize flour and arrowroot flour. Some foods naturally form a protein gel when cooked such as eels and elvers, and sipunculid worms which are a delicacy in the town of Xiamen in Fujian province of the People’s Republic of China. Jellied eels are a delicacy in the East Ene.! of London where they are eaten ‘with mashed potatoes.
Potted meats in aspic, (a gel made from gelatine and clarified meat broth) were a common way of serving meat off-cuts in the UK until the 1950s. Many jugged meats are also jellied. Fruit preserved by jellying is known as jelly, marmalade, or fruit preserves. In this case, the jellying agent is usually pectin, either added during cooking or arising naturally from the fruit. Most preserved fruit is also sugared in jars. Heating, packaging and acid and sugar provide the preservation. Potting A traditional British way of preserving meat (particularly shrimp) is by setting it in a pot and sealing it with a layer of fat. Also common is potted chicken liver; compare pate.
Jugging Meat can be preserved by jugging, the process of stewing the meat (commonly game or fish) in a covered earthenware jug or casserole. The animal to be jugged is usually cut into pieces, placed into a tightly-sealed jug with brine or gravy, and stewed. Red wine and/or the animal’s own blood is sometimes added to the cooking liquid. Jugging was a popular method of preserving meat up until the middle of the 20th century. Irradiation Irradiation of food is the . exposure of food to ionizing radiation; either high energy electrons or X -rays from accelerators, or by gamma rays (emitted from radioactive sources as Cobalt-60 or Caesium-13 7).
The treatment has a range of effects, including killing bacteria, molds and insect pests, reducing the ripening and spoiling of fruits, and at higher doses inducing sterility. The technology may be compared to pasteurization; it is sometimes called ‘cold pasteurization’, as the product is not heated. Irradiation is not effective against viruses or prions, it cannot eliminate toxins already formed by microorganisms, and is only useful for food of high initial quality. The radiation process is unrelated to nuclear energy, but it may use the radiation emitted from radioactive nuclides produced in nuclear reactors. Ionizing radiation is hazardous to life; for this reason irradiation facilities have a heavily shielded irradiation room where the process takes place.
Radiation safety procedures ensure that neither the workers in such facility nor the environment receive any radiation dose from the facility. Irradiated food does not become radioactive, and national and international expert bodies have declared food irradiation as wholesome. However, the wholesomeness of consuming such food is disputed by opponents[2] and consumer organizations. [3] National and international expert bodies have declared food irradiation as ‘wholesome’; UN-organizations as VHO and F AO are endorsing to use food irradiation. International legislation on whether food may be irradiated or not varies worldwide from no regulation to full banning. It is estimated that about 500,000 tons of food items are irradiated per year worldwide in over 40 countries.
These are mainly spices and condiments with an increasing segment of fresh fruit irradiated for fruit fly quarantine. Modified atmosphere Is a way to preserve food by operating on the atmosphere around it. Salad crops which are notoriously difficult to preserve are now being packaged in sealed bags with an atmosphere modified to reduce the oxygen (C02) 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. Grains may be preserved using carbon dioxide. A block f dry ice is placed in the bottom and the can is filled with grain. The can is then “burped” of excess gas. The carbon dioxide from the sublimation of the dry ice prevents insects, mold and oxidation from damaging the grain. Grain stored in this way can remain edible for five years. – Nitrogen gas (N2) at concentrations of 98% or higher is also used effectively to kill insects in grain through hypoxia. However, carbon dioxide has an advantage in this respect as it kills organisms through both hypoxia and hypercarbia, requiring concentrations of only 80%, or so. This makes carbon dioxide preferable for fumigation in situations where an hermetic seal cannot be maintained. Burial in the ground
Burial of food can preserve it due to a variety of factors: lack of light, lack of oxygen, cool temperatures, pH level, or desiccants in the soil. Burial may be combined with other methods such as salting or fermentation. Many root vegetables are very resistant to spoilage and require no other preservation other than storage in cool dark conditions, for example by burial in the ground, such as in a storage clamp. Century eggs are created by placing eggs in alkaline mud (or other alkaline substance) resulting in their “inorganic” fermentation through raised pH instead of spoiling. The fermentation preserves them and breaks down some of the complex, less flavorful proteins and fats into simpler more flavorful ones.
Most foods can be preserved in soil that is very dry and salty (thus a desiccant), or soil that is frozen. Cabbage was traditionally buried in the fall in northern farms in the USA for preservation. Some methods keep it crispy while other methods produce sauerkraut A similar process is used in the traditional production ofkimchi. Sometimes meat is buried under conditions which cause preservation. If buried on hot coals or ashes, the heat can kill pathogens, the dry ash can desiccate, and the earth can block oxygen and further contamination. If buried where the earth is very cold, the earth acts like a refrigerator. Controlled use of micro-organism
Some foods, such as many cheeses, wines, and beers will keep for a long time because their production uses specific micro-organisms that combat spoilage from other less benign organisms. These micro-organisms keep pathogens in check by creating an environment toxic for themselves and other micro-organisms by producing acid or alcohol. Starter micro-organisms, salt, hops, controlled (usually cool) temperatures, controlled (usually low) levels of oxygen and/or other methods are used to create the specific controlled conditions that will support the desirable organisms that produce food fit for human consumption. High pressure food preservation High pressure food preservation refers to high pressure used for food preservation. Pressed inside a vessel exerting 70,000 pounds per square inch or more, food can be processed so that it retains its fresh appearance, flavour, texture and nutrients while disabling harmful microorganisms and slowing spoilage. ” By 2001, adequate commercial equipment was developed so that by 2005 the process was being used for products ranging from orange juice to guacamole to deli meats and widely sold. MEAT PRESERVATION Meat is generally animal muscle, which is mostly water, protein and fat. Even after cooking, most meat products are about 50% moisture so it is a great growing media for micro-organisms. So the main problem with meat, poultry and fish is how to preserve it from microbial spoilage. Ideally, we could just slaughter the animals on need basis. It is rare, however, to eat a whole carcass so soon after slaughter to avoid having to preserve it.
Since some of the methods used to preserve meat by removing or limiting the water availability, this post counts as part of my series on water. The water limiting methods are drying, salting, and smoking. Other methods include pickling, jellying, lye, freezing, canning, refrigeration, vacuum-packing, and modified atmosphere packing. Drying is probably the oldest method used for preserving anything. It works by removing water and, therefore, preventing microbes from growing. For meat, it is important to have water moving from inside the muscles to the outer surface where it evaporates, without a crust forming on the surface. If a crust forms, the internal tissues stay moist allowing anaerobic bacteria growth, which in turn causes spoilage.
This can be prevented by reducing the thickness of the pieces of meat being dried so that there is a high surface area to volume ratio. The final moisture content should be around 3 -10%. The loss of water causes muscle to shrink and become firmer. There are changes to the flavor and taste as fat is oxidized. If too much oxidation takes place, the fat will go rancid causing off-flavors. Jerky is the commonest form of dried meat which is not the most pleasant way to consume anything, especially meat. Dried meat is also used in soup powders. Dried meat products can also be rehydrated. Curing is at least two processes in one, salting and smoking. Meat is salted by either dry or wet curing.
Dry curing is when salt is rubbed onto the surface of the meat and wet curing is when the meat is left soaking in a 15-20% brine. Sugar and spices can also be added to affect the color and flavor. The meat is preserved in sugar or salt and nitrates or nitrites. As well as reducing microbial growth through osmotic effects, the sugar, salt and nitrate/nitrite are antimicrobial agents. According to Berlitz et ai, low salt concentrations (less than 5%) cause meat to swell and higher concentrations induce shrinkage. Meat retains its natural color because the loss of water actually concentrates the myoglobin, which causes the color. Nitrites and nitrates preserve the color.
Smoking is usually associated with salting – uncured meat is rarely smoked. Smoking causes the moisture content to drop up to 40% and compounds in the smoke have antimicrobial effects. Some compounds in smoke are antioxidants, so smoking protects the fat as well as preventing microbial damage. Smoking has to be carried out at temperatures high enough to prevent microbes from growing but lower enough to prevent the meat from cooking and becoming tough or burnt. There are many different techniques, but typically these are divided into: 1. Hot smoking (50-85° C) for less than an hour to several hours; 2. Warm smoking (25 – 50° C) for several days; 3.
Cold smoking (12 -250 C) for up to several weeks. Smoked foods include kippers, smoked salmon (lox), ham and bacon, and sausages. Smoking can be added as a flavoring, but then it does not preserve the meat. Just for information on the other preservation techniques: Pickling typically reduces the pH by cooking the meat in vinegar. It is the original way that corned beef was prepared – now it is also canned after preservation keeping it even longer. Using lye is how Lutefisk is made and preserves the food by increasing the pH. Jellying or aspic is converting the connective tissues to gelatin by cooking for a long time and then using the resulting jelly to preserve the meat.
PRESERVATION OF MILK Gail Borden tried his hand at various professions including land surveying and publishing before he became an inventor. His first invention was a ‘meat biscuit’ that did not catch on. Then he turned his attention to the preservation of milk. Some say he decided to find a way to preserve milk for long periods when he found there was no milk on board the ship he was traveling while returning from a trip to England. Many people had tried to find a way to preserve milk, but without success. The only method available was heating the milk every few hours. Prolonged boiling or constant heating scorched the milk. Borden found a way out.
He used a copper kettle, otherwise known as a vacuum pan. Inside his vacuum pan a heating coil warmed the milk slowly and evenly, allowing gradual evaporation. After the water had vaporized, what was left was concentrated milk or condensed milk. In a vacuum, milk evaporates at a lower temperature, so it does not get scorched even if boiled for long periods. Borden received a patent for the invention in 1856. For the first time milk could be stored for days or weeks at a stretch without recourse to boiling. For the first time, too, it could be distributed over great distances. Borden opened a milk-condensing factory in New York, and began peddling condensed milk door-to-door.
He enforced strict hygiene on farmers who wanted to sell him milk- he insisted they wash udders thoroughly before milking; sweep barns clean and keep manure away from milking stalls. The technology pioneered by Borden was carried further when scientists found a way to remove the moisture from condensed milk to make powdered milk, which can last even longer. The famous copper kettle of Borden still sits in a corner of the Agricultural Hall at the Smithsonian’s National Museum of American History. CONDENSED MILK What is condensed milk? Condensed milk is milk from which a portion of water has been removed. Who was the first to make condensed milk? The American entrepreneur, Gail Borden. When? He set up the first factory to make condensed milk in Connecticut, USA, in 1856. Was it an instant success? No.
Borden had to close down the factory. He tried again in 1857 ; failed again. In 1858 he made a third attempt – and this time he succeeded. Condensed milk began to sell in a big way and Borden made a fortune. Was Borden the only one making condensed milk in the nineteenth century? No. In Europe a factory to make condensed milk came up in Switzerland around 186O. In 1867 the famous Milkmaid brand of condensed milk was introduced to the world. FOOD STORAGE FOR FOOD SAFETY The method and techniques used to clean, prepare and store food not only affects the taste texture and nutritional values, but also plays a vital role in preventing food spoilage and food born illnesses.
Using the right and proper techniques to prepare and store food can go along way in keeping the food healthy and in maintaining their nutritive quality, it also preserve the taste, texture and appearance and also help to u e the food economically exposure to heat, light, moisture and air can cause food spoilage and increase the risk of food poisoning. Improper handling and storage cause loss of nutrients and affect the color, texture and flavor ‘of food. Heat and humidity increases the risk of food spoilage. Therefore foods should not be stored near warm place, e. g. stores or refrigerator. All perishable foods such as meat, fish, poultry eggs milk and other dairy products should be refrigerated or frozen immediately after purchase or cooking.
In case of canned food; care should be taken to use the oldest can first. Canned foods should be stored away from moisture in (IOC- 21C) temperature range. Labels should always be read carefully as they contain important information regarding storage. Dry foods should be kept in a cool, dark and dry place and should be utilized before the date of expiry. Meat, poultry and fish should be stored in the coldest part of the refrigerator. Meat should be wrapped in the freezer paper and should not be frozen for more that 3-4 days as it affects the flavor and appearance of the product. Meat should not be defrosted at room temperature instead it should be defrosted on the bottom shelf of the refrigerator.
If meat is defrosted in micro wave oven it should be immediately cooked. Fish can’t be kept for more that few hours at refrigerator temperature. Fresh milk and cream should be tightly sealed or covered to prevent tainting by odors from other foods. Non fat powdered milk can be stored at room temperature in closed containers; butter is best refrigerated in its original wrapper. Soft cheese can be stored in closed containers in refrigerator and hard cheese can best be stored in a cool dark cupboard. Grains, flours, nuts and other foods can be stored in plastic, metal or glass container with tight fitted lids. Cereals and crackers are normally best kept in closed containers at room temperatures.
Unshelled nuts can be kept at room temperature for 3-6 months, shelled nuts may become rancid unless refrigerated or frozen. Raw fruits and vegetables often slowly lose their vitamins when kept at room temperature. Most fruits and vegetables are best stored at 10C; if refrigerated they should be put in crisper section. Fruits and vegetables should not be stored for long period in sealed plastic bags as they cit off the air supply causing the product to rot. Paper and cellophane are better storage material because they are permeable. Peas and beans should be refrigerated in their pods. The green top should be cut off from the root vegetables as they continue to draw nourishment for the roots.
Potatoes are covered with mesh which protects them from light while still allow ail to circulate. Freezing raw fruits and vegetables cause the water they contain to form ice crystals that break down cell membranes and walls resulting in mushy texture and loss of nutrients. Enzymatic activity also spoils fruits and vegetables; blanching prevents this problem. Vegetables should be emerged for a second in rapidly boiling water to deactivate their enzymes, and then plunge them into the cold water to stop the cooking process. Most fruits . are not suitable for blanching; browning and deterioration can be prevented by packing them in a solution of sugar other with or without ascorbic acid. Prof.
Pinoo Andrabi Senior lecturer FOOD TECHNOLOGY Waste NotWant Not In the last few decades India has made great strides in fruit and vegetable production. Recent food production statistics indicate that India is the second largest production of fruits in the world after Brazil. Major Indian fruit include banana, citrus fruits mango, guava, apple, pineapple and grapes. These are canned or processed into fruit juices, fruit concentrates, dehydrated fruit, jams and jellies However, it is estimated that 20 to 30 percent of the fruits produced in the country arc not utilized properly and processed fruits account for less than 3 percent of production.
Nearly 30 percent of the fruits are lost due to spoilage during handling, transportation and lack of storage and processing facilities. The fruit and vegetable processing industry in India is highly decentralized. A large number of units are cottage / home scale ones. India incurs precious loss not only in terms of revenue, but also in terms of health. Efforts arc thus needed to Convert surplus production of fruits and vegetables to value added products. Food processing can be defined as treatments between harvest and consumption i. e. handling transportation, refrigeration, holding, washing, trimming, bleaching, freezing, Canning, drying, irradiation, chemical preservation, packaging, storage and lastly cooking.
Due to the processes involved, large quantities of waste material are left over. Efficient disposal of these wastes in form of peelings, coring, seeds, stones, rinds, skin-trimmings and over ripe fruits minimizes pollution hazards. Utilization of Mango Waste Peel forms 12-16 percent of mango waste is a good source of nutrients such as sugar, pectin, proteins and fibers. Mango peel has been used for production of fungal protein, carboxymethy cellulose and polygalacturonase by fungi. The peel and pulp portion left after juice extraction can be utilized to manufacture of juice, nectar etc. by pectin enzyme treatment. The kernel is a good source of nutrients such as starch, fats and proteins.
Kernel oil could be used as partial replacement for tallow and cocoa butter in the preparation of quality soaps and confectionary products. Kernel fat added at the rate of one percent in ghee prepared from buffalo milk can act as an antioxidant. Kernel oils or fats can be used for manufacturing soaps because of the high stearic acid content. Utilization of Citrus Waste Citrus represents the third most important fruit in India. A fair amount of citrus fruits are consumed by the consumers and processing factories. Citrus waste constitutes peels from oranges and the rags, seeds and sludges obtained from lime. Citrus wastes are rich source essential oils, pectin’s, citric acid and a variety of by-products including cattle feed.
Citrus peel can be processed into candies: It can be used for extraction of essential oils used in confectionery and perfumery traders. Mandarin essential oil is extracted in small quantity from citrus peel. The rag of galgal and orange can be utilized for the extraction of pectin. Utilization of Apple Waste Indian apple production is around 12 lakh tones. Apples are processed into various products such as juice, concentrate, vinegar, sauce, butter etc. Waste from the apple processing industry in the form of peel, core and pomace can be utilized for production of pectin and various edible products. Apple pomace is a good source of pectin, which can be extracted for use in production of jam, jellies etc.
Citric acid can be prepared from apple pomace by growing Aspergillus niger on it under controlled conditions. It has been estimated that an apple processing factory generating 10,000 tones (fresh weight) of apple pomace per year could anticipate generating 3,30,000 cum. of biogas per year (55%) methane equivalent in calorific value to about 1,97,000 ltr of diesel or 1,22,700 kg of LPG or 1,73,000 ltr of kerosene oil. Utilization of Guava Waste The annual production of guava is around 6. 2 lakh tones. Guava is a good source of pectin and seed oil, which enhances its commercial value. Peeling, seeds and cores are the waste obtained from guava processing.
Discarded guava seeds contain about 5-13 percent oil rich in essential fatty acids. Guava pomace can be used to fortify animal feed. Yasmeena Ali Roll no. 10 B. Sc. Home Science (Certificate Course) ALL ABOUT EGGS – BUYING, STORING, SEPARATING AND USING EGGS STORAGE: While eggs will keep in your refrigerator for several weeks, it’s important note that they can lose some quality. A little known fact about eggs is that they can absorb adour from your refrigerator if stored in an open container, although this shouldn’t be a major problem unless you are storing eggs along side opened containers of onions and garlic or other such strong smelly foods.
DO YOU NEED ONLY EGG WHITES OR ONLY EGG YOLKS FOR A PARTICULARS RECIPE? Don’t know out the leftovers; find another recipe to cook which will use the other portion. Type in “egg yolk” or “egg whites” in our search engine to find recipes that use one or the other. Once out of the shell, you can keep eggs whites for about a week in the refrigerator and egg yolks will keep for two or three days, although be sure to cover them with water. HOW TO SEPARATE EGGS Cold eggs are easier to separate. Gently crack the egg open in the centre, either hitting it gently with a knife, or using a convenient counter edge. Hold the egg upright and gently pull off the top half of the shell. You now have three options
Hold your hand over the egg white bowl, pour the egg into your hand and let the egg white ooze through your fingers while retaining the yolk hand – a very easy, albeit inelegant, way to separate eggs. Make sure to wash your hands first. Over the egg while bowl, gently pour your contents between the two shell halves, allowing the egg whites to pour out in the process, leaving just the yolk in other half shell. Be gentle, it’s possible to break the yolk if you are not careful. Buy a handy-dandy gadget called an Egg Separater, which looks like a small measuring cup. The egg yolk is retained in the cup while white are allowed to drip through. BEATING EGG WHITES
Egg whites will not whip (they just won’t) if they come into contact with even the slightest trace of fats grease or egg yolk. This is why it’s a good idea when separating eggs to have three bowls: one for the yolks, one for the whites and one bowl to separate over so that you won’t have to throw out a whole batch if one yolk breaks while separating. It is also a good idea to wash your hands, beaters and bowl before beginning as well, to make sure that they are grease free. Egg whites that are at room temperature will whip easier and faster. You can add 1/4 teaspoon of cream of tartar to help the process along (although it is not necessary unless your recipe calls for it).
Use mixer for best results, although you can use whisk if you want a good work out. HOW TO COOK EGGS: Eggs are quick, easy and nutritious comfort food in and of themselves. Here are some popular ways of preparing eggs. BOILED: Put your eggs in a pot (avoid aluminum as it will darken) and cover with cold water. Add a pinch of salt. Bring the pot to a boil over high or medium high hear, then lower the heat and simmer. Depending on the size of your egg, they will need to simmer for 2-3 minutes for soft boiled, about 4-5 minutes for medium and 15-20 minutes for hard boiled. Drain the eggs and immense them immediately in cold water to stop the cooking process. Refrigerator boiled eggs will keep for about a week.
FREID: Add a small amount of butter or oil to your skillet (non-stick pans will need very little to none of this) and heat. When you can drop of water into the pan and hear it sizzle, it’s time to cook the eggs. Carefully crack the eggs into the pan. For sunny side up eggs, allow them to cook for about 3-4 minutes without turning tillthey are done to a consistency you like), before removing them from the pan. If you prefer your eggs turned over, firs cook the eggs for about 2 minutes before using your spatula to flip the eggs over. The amount of time the aimed eggs are cooked will depend on how you like to eat your eggs. SCRAMBLED : The cooking procedure for scrambled eggs is the same as the fried.
First beat your eggs in a bowl (you can add table spoon or so of milk per egg as well as salt, pepper, seasoning etc. Pour into the skillet and cook while gently until the eggs reach the desired consistency. POACHED: Cover the bottom of a small pot or skillet with about two inches of water and bring to a simmer. Break an egg into a small bowl. Stir the water to create a small whirlpool effect and drop the egg from the centre. Cook for 3-5 minutes before removing the egg with a slotted spoon. FOOD TECHNOLOGY Fermenting is Fun: Fermenting your own foods can be a healthy, fun and nutritious hobby. Anything you can make at home is much better than commercialized foods. We have put a summary of fermented foods followed by a few recipies.
About a thousand years ago, our ancestors began to experimenting with fermenting their own foods with beneficial strains to prevent spoilage, fight infections and increase absorption of nutrients. This action further allied our bodies with the microbial world. Benefits of Fermented Food: Nobel Prize winner Dr. Elie Metchnikoff was one of the first scientists to recognize the benefits of fermented foods. His research in the early 1900’s focused on the Bulgarians. He believed the daily ingestion of yogurt was a major contribution to their superior health and congitivity. Detoxify ; Pressure: If there’s anything that the microbial world does well, it is detoxifying things.
Today Bacteriologists periodically visit old military facilities in search of new strains of bacteria living off contaminants in the soil. If you put it in the ground and give them enough time to mutate and evolve, these microbes will find a way to break down. Bulgarians perfected the art of detoxifying and preserving milk (removing the lactose and predigesting the proteins) and performing it into yogurt and cheese. The caucarians used Kefir grains for the same purpose – detoxify milk products to make Kefir, vegetables were also fermented to preserve them from spoilage. Most of the pickled products found on our grocery shelves were at one time a fermented product. Pickles, saurkruat and even catsup (a Chinese word for pickled fish brine).
However since fermentation isn’t always a uniform process, manufacturers found another way to make these products. Nutrition to Boot: Fermented products are a great source of amino acids, vitamins and minerals. The process of fermentation increases the amount of some vitamins. Fermented milk is great source of vitamin C. saverkrat often served as military ratios in ancient armies, most notably the Mongolians and was used to prevent scurvy. The process of fermentation also increases bio-availability of these foods. Harnessing the power of microbes: Pills versus food: We have already mentioned earlier that diary products fermented with lacto bacilli have been shown to kill pathogenic bacteria, such as H. Pylori, while the lactobacilli along did not.
This means that some of the antibiotic properties of these good bacteria may be missing in the probiotic pills you seen on the shelves. Also, you have no way of verifying the potency of vitality of these products. Bacteria are living organisms and must be alike when you eat them in order to reap their benefits. It does good to ingest dead, good bacteria. We can make all the saverkrat Kefir and yogurt we will need. Not only will you be getting the benefits of these beneficial bacteria, you will be making delicious and healthy meals as well. The only benefit store probiotics offer is convenience. However, once you get started, fermenting your own food is very easy. Please use caution: Before we get too far into fermenting your own oods, we want to emphasize the caveats of fermentation. The process of fermentation is only good for you if it occurs outside your body. What does this mean? It means that if you ingest foods that provide an abundance of sugar and growth media for bacteria, they will ferment those foods inside you. An over growth of fermentative bacteria in your body can cause all kinds of medical problems including Chron’s Disease, Ankylosing Spondylitis. Commercial Versus Homemade: In our opinion homemade products are better all around, for one you do not have to trust a manufacturer with your health. You can purchase the best milk and / or vegetables to use.
Commercial products are usually geared for taste and not health. In the case of yogurt, this means that commercial yogurt usually has a high lactose content and is usually loaded with sugar. Homemade yogurt can be made to eliminate virtually all of the lactose and will be much fresher than anything you can buy in a store. If the taste is not to your liking, you can add in fresh fruit and / or honey to sweeten it up. Store brought Kefir has the same problems, you have no control over the lactose content in the end product. Another thing to consider is, real Kefir is difficult to find in the store. Quite often a manufacturer will label a product as Kefir when in fact it is not the real thing.
In order for Kefir to be real, it needs to made from Kefir grains and not a powdered starter. As for fermented vegetables, such as saverkrat most commercial products have been pasteurization process not only kills the beneficial bacteria, but may also destroy many of the enzymes and nutrients. Commercial saverkrat may also contain a fair amount of unnatural preservatives. We know that you will find fermenting your own foods at home more rewarding, healthier, cheaper than probiotics and more enjoying than anything you could. To get started we have listed a few easy at home products you can make. 01. Yougurt: Making yogurt is very easy, especially if you own a yogurt maker.
We recommend purchasing a yogurt met Multi they are cheap, easy to use and can make 2 quarts per batch. Once you have a started and yogurt maker, al you need is some milk (using half-n-half) and some patience. The directions that come with the maker provide a fermentation of 6 hrs. however, it is good to ferment your yogurt for 24 hrs to eliminate all lactose in the yogurt. Any residual lactose could be used as food for bacteria already found in your GI-tract and result in fermentation in your intestines. Caution: Those of you following the SC Diet must ferment your yogurt for 24 hours in order to stay on the diet. 02. Kefir: Kefir is a fermented food (milk product) made from Kefir grains.
Unlike yogurt, Kefir is made from Lactobacillus bacteria and several different yeast organisms and is fermented at room temp. The most difficult step in making Kefir is getting some one to sell/ give you some Kefir grains. It would be impossible for us to give Kefir any justice. 03. Saverkrat: Can be make in several different ways. The traditional recipie involves shredding and pounding fresh cabbage, adding salt and submerging it under water for several days. The natural bacteria in the cabbage, such as lactobacillus plantarum, will natural begin to ferment the cabbage while the salt inhibits other microbes. You can eliminate the use of salt altogether by inoculating the shredded cabbage and water solution with yogurt starter or Kefir grains. Shagufta Khursheed
Certificate Course of Food Technology HOW TO MAKE PICKLE Indian Pickle Recipie: Indian pickles recipie spicy pickles are very important item in Indian meal. Pickles enhances the taste of the meal and increases the satisfaction after every meal. Pickles are easy to prepare with right ingredients and can be preserved for months. Here we can find mouth watering homemade pickles recipies which have to be consumed with a few days and pickles that can be preserved for months. 01. Carrot Pickle Recipie: Ingredients: 3 cups water 230 gms carrots (scrapped and cut into 2” long sticks) 1 ? tb sp mustard seeds ? tsp chilli powder 1/8th tsp each ground mace, cloves and cardamom. 2 tsp salt /4th cup shredded jaggery (gur) 1/3rd cup mustard oil Preparation: Boil the water in 2 litre saucepan. Add carrots and blanch for a minute. Drain the water and then spread carrots on a clean cloth and sundry or spread them on a towel lined cookie tray and air dry in an oven (200 degree Fahrenheit) of a hour. In a bowl mix the mace, cloves, cardamom, salt and jaggery. Add the carrots and toss to mix. Transfer to a sterilized glass jar pour the mustard oil into a small saucepan and place it over a moderate heat. As soon as oil begins to smoke remove it from the heat and cool it for 11 minutes, then pour it into the jar and cover it with a clean cloth.
Set the jar in sunlight for 13-14 days bringing it in door every night. Shake the jar 2 or 3 times daily. 02. Dry Fruit Pickle: Redolent with saffron, a traditional pickle gets a new look. Make 1 ? look. Ingredients: 1 cup grated raw mangoes A pinch of turmeric power (Haldi) ? cup chopped day fruits – Cashew nuts (Kaju, almonds (badam) walnuts (akhroot, apricot (Zardalu). ? tsp saffron (Kesar) roasted for 5 sec. 1 ? cups sugar ? tsp saffron 2 one – inch pieces cardamom (dalchini) 1 tsp cardamom (elaichi) powder. 2 nos cloves (laung) Salt to taste. Preparation: 1. Combine the grated mangoes, salt and turmeric powder and set aside for 15 minutes. 2.
Start adding 2 table spoons of sugar at a time and stir continuously with a spoon whisk till al the sugar is nearly dissolved. The entire process will take about 30 to 35 minutes. 3. Add cinnamom, cardamom and cloves. 4. Heat a pan, add the mango and sugar mixture and continue stirring over a very slow flame till the sugar dissolves completely and small bubbles appear on the surface of the mixture (approx. 3 to 4 minutes). 5. Stir in chopped day fruit and saffron, remove from the flame and the mixture to cool completely. Store in a sterilized jar in a cool dry place for up to a year. Handy Tip: Use Ladwa, a round variety of raw mangoes available at some vegetable vendors or any other type of raw mangoes.
