Food Science Introduction

Food Science

Food is one of the basic needs of the human being. It is required for the normal functioning of the body parts and for a healthy growth. Food is any substance, composed of carbohydrates, water, fats and/or proteins that are either eaten or drunk by any animal, including humans, for nutrition or pleasure. Items considered food may be sourced from plants, animals or another kingdom such as fungus. On the other hand, Food science is a study concerned with all technical aspects of food, beginning with harvesting or slaughtering, and ending with its cooking and consumption. It is considered one of the life sciences, and is usually considered distinct from the field of nutrition.

Basic composition of food:

Our body requires carbohydrates, proteins, fats, enzymes, vitamins and minerals for a healthy growth. However, our body cannot produce all these nutrients. Hence, food is the only source to obtain these nutrients in an adequate quantity. If we don‘t get these nutrients in sufficient amount, then we may suffer from a number of health problems. So a balanced diet is always recommended which is defined as a diet containing carbohydrate, protein, fat, dietary fibres, vitamin & minerals in right proportion. Carbohydrates, proteins, and fats supply 90% of the dry weight of the diet and 100% of its energy.  All  three  provide  energy  (measured  in  calories),  but the  amount  of  energy  in  1 gram differs: 4 calories in a gram of carbohydrate or protein and 9 calories in a gram of fat. These nutrients also differ in how quickly they supply energy. Carbohydrates are the quickest, and fats are the slowest.

Carbohydrates, proteins, and fats are digested in the intestine, where they are broken down into  their  basic  units:  carbohydrates  into  sugars,  proteins  into  amino  acids,  and  fats  into fatty  acids  and  glycerol.  The  body  uses  these  basic  units  to  build  substances  it  needs for growth, maintenance, and activity (including other carbohydrates, proteins, and fats).

Food science is a highly interdisciplinary applied science. It incorporates concepts from many different fields including microbiology, chemical engineering, biochemistry, and many others. Some of the sub disciplines of food science include:

·         Food processing - the set of methods and techniques used to transform raw ingredients into food or to transform food into other forms for consumption by humans or animals either in the home or by the food processing industry.

·         Food safety - the causes, prevention and communication dealing with foodborne illness.

·         Food microbiology - the positive and negative interactions between micro-organisms and foods.

·         Food preservation - the causes and prevention of quality degradation.

·         Food engineering - the industrial processes used to manufacture food.

·         Product development - the invention of new food products.

·         Sensory analysis - the study of how food is perceived by the consumer's senses.

·         Food chemistry - the molecular composition of food and the involvement of these molecules in chemical reactions.

·         Food packaging - the study of how packaging is used to preserve food after it has been processed and contain it through distribution.

·         Food technology - the technological aspects of food.

·         Food physics - the physical aspects of foods (such as viscosity, creaminess, and texture).

Some of the sub disciplines in detail:

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 and drawbacks:

Benefits

Ø  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.

Ø  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.

Ø  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.

Ø  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.

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

Ø  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.

Ø  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.

Ø  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

Ø  Any processing of food can affect its nutritional density. The amount of nutrients lost depends on the food and processing method. For example the heat destroys the 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. A cursory glance of the table indicates that, in the majority of foods, processing reduces nutrients by a minimal amount. On average this process reduces any given nutrient by as little as 5%-20%.

Ø  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.

Ø  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. Certain additives can also result in an addiction to a particular food item. As effects of chemical additives are learnt, changes to laws and regulatory practices are made to make such processed foods more safe.

Ø  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.[citation needed] 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.

Ø  Typical Maximum Nutrient Losses (as compared to raw food).

Food safety is a scientific discipline describing handling, preparation, and storage of food in ways that prevent foodborne illness. This includes a number of routines that should be followed to avoid potentially severe health hazards. The tracks within this line of thought are safety between industry and the market and then between the market and the consumer. In considering industry to market practices, food safety considerations include the origins of food including the practices relating to food labeling, food hygiene, food additives and pesticide residues, as well as policies on biotechnology and food and guidelines for the management of governmental import and export inspection and certification systems for foods. In considering market to consumer practices, the usual thought is that food ought to be safe in the market and the concern is safe delivery and preparation of the food for the consumer.

Food can transmit disease from person to person as well as serve as a growth medium for bacteria that can cause food poisoning. In developed countries there are intricate standards for food preparation, whereas in lesser developed countries the main issue is simply the availability of adequate safe water, which is usually a critical item.[1] In theory, food poisoning is 100% preventable.

The five key principles of food hygiene, according to WHO, are:

·         Prevent contaminating food with pathogens spreading from people, pets, and pests.

·         Separate raw and cooked foods to prevent contaminating the cooked foods.

·         Cook foods for the appropriate length of time and at the appropriate temperature to kill pathogens.

·         Store food at the proper temperature.

·         Do use safe water and raw materials.

Food packaging is packaging for food. A package provides protection, tampering resistance, and special physical, chemical, or biological needs. It may bear a nutrition facts label and other information about food being offered for sale.

Functions of food packaging:

·         Physical protection - The food enclosed in the package may require protection from, among other things, shock, vibration, compression, temperature, bacteria, etc.

·         Barrier protection - A barrier from oxygen, water vapor, dust, etc., is often required. Permeation is a critical factor in design. Some packages contain desiccants or oxygen absorbers to help extend shelf life. Modified atmospheres or controlled atmospheres are also maintained in some food packages. Keeping the contents clean, fresh, and safe for the intended shelf life is a primary function.

·         Containment or agglomeration - Small items are typically grouped together in one package to allow efficient handling. Liquids, powders, and granular materials need containment.

·         Information transmission - Packages and labels communicate how to use, transport, recycle, or dispose of the package or product. Some types of information are required by governments.

·         Marketing - The packaging and labels can be used by marketers to encourage potential buyers to purchase the product. Package design has been an important and constantly evolving phenomenon for several decades. Marketing communications and graphic design are applied to the surface of the package and (in many cases) the point of sale display.

·         Security - Packaging can play an important role in reducing the security risks of shipment. Packages can be made with improved tamper resistance to deter tampering and also can have tamper-evident features to help indicate tampering. Packages can be engineered to help reduce the risks of package pilferage; some package constructions are more resistant to pilferage and some have pilfer-indicating seals. Packages may include authentication seals to help indicate that the package and contents are not counterfeit. Packages also can include anti-theft devices, such as dye packs, RFID tags, or electronic article surveillance tags, that can be activated or detected by devices at exit points and require specialized tools to deactivate. Using packaging in this way is a means of retail loss prevention.

·         Convenience - Packages can have features which add convenience in distribution, handling, stacking, display, sale, opening, reclosing, use, and reuse.

·         Portion control - Single-serving packaging has a precise amount of contents to control usage. Bulk commodities (such as salt) can be divided into packages that are a more suitable size for individual households. It also aids the control of inventory: selling sealed one-liter bottles of milk, rather than having people bring their own bottles to fill themselves.

Industrialization of food:

Several companies in the food industry have played a role in the development of food technology. These developments have contributed greatly to the food supply and have changed our world. Some of these developments are:

·         Instantized Milk Powder - D.D. Peebles (U.S. patent 2,835,586) developed the first instant milk powder, which has become the basis for a variety of new products that are rehydratable. This process increases the surface area of 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 - Decaffeinated 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 water, heat and solvents 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.