Biochemistry Of Food Processing And Preservation Pdf
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Food processing has come to be associated with ramen noodles, canned meat, and spongy snack cakes.
Food processing has come to be associated with ramen noodles, canned meat, and spongy snack cakes. The health concerns raised by these products have led many to assume that all processed foods are unhealthy, but do they deserve their reputation? Businesses use food processing techniques to transform raw foods and ingredients into new products. These techniques run the gamut and include milling grains into flour, crushing seeds to extract their oil, churning milk into butter, mixing ingredients to make batter, and baking cookies on an assembly line.
Meat processing, meanwhile, can involve techniques like cutting, deboning, and removing guts from carcasses. While some food processing techniques use cutting-edge technology, others have been practiced for millennia. Thousands of years before food scientists figured out how to make dinosaur-shaped chicken nuggets, early Egyptians were brewing beer and baking leavened bread. Today, for better and for worse, nearly all our food is processed in some way.
Food processing offers important benefits to businesses and consumers, including a more varied food supply and foods with a longer shelf life. Certain aspects of food processing, however, raise concerns over dietary health, worker health, and food safety. In the s, Napoleon Bonaparte offered a prize to the scientist who could best develop ways to preserve foods for the armies of France.
Photo credit: mlhradio, Cropped from original. After fruits and vegetables are harvested, they begin to lose nutrients. Freezing, canning, or storing fresh produce under proper conditions can slow nutrient losses.
While canned foods are often perceived as less nutritious than fresh or frozen ones, studies show this is not always the case. It depends on the type of produce, how long it had been stored, and how it will be prepared. Over time , yeasts, molds, bacteria, and other forces cause food to spoil, making it foul-tasting, less nutritious, and potentially unsafe to eat. Many of the oldest food processing techniques, such as drying fruit, pickling vegetables, salting meat, and fermenting dairy e.
Processing can also help to inhibit or destroy pathogens disease-causing organisms that may contaminate food. Preservation techniques such as refrigeration, fermentation, dehydration, and the use of salt, sugar, or chemical preservatives can slow or stop the growth of pathogens. Heat processes, such as pasteurization and cooking, are used to destroy them.
Large processing plants, for example, often handle large volumes of products from many different sources. If a shipment of spinach from one farm is contaminated with E. Granola advertisement, A variety of processed breakfast cereals can be derived from just a few different types of grain.
Kellogg and his brother invented a granola-like cereal designed to fit the vegetarian diets of their patients. They would later found the company that bears their name. Post, founder of General Foods, spent time as a patient at the very same sanitarium.
Image public domain. Fermentation transforms food through the action of yeasts and bacteria. This process has been harnessed by humans for millennia to make traditional foods and beverages such as wine, kombucha, sauerkraut, and yogurt. In addition to producing a variety of flavors and textures, fermentation can promote gut health, preserve foods, improve nutritional quality, and reduce cooking times.
By modifying the flavors, textures, aromas, colors, and form of foods and raw ingredients, food processing can create greater variety in our food supply.
Every year, roughly 20, new processed food products are introduced on retail shelves. Processing can also create products that require little or no preparation on the part of consumers. Among U. While fast food items and convenience foods are not universally unhealthy, many are made with refined grains, are high in added sugars and unhealthy fats, and have low nutritional value. Hominy, or nixtamalized maize. Many traditional food processing techniques increase the availability of nutrients.
Early Central American peoples, for example, prepared corn by soaking and cooking it in wood ashes. The process, called nixtamalization, made corn easier to grind and increased the availability of niacin, a B vitamin. When corn was later adopted as a staple crop among Europeans, they neglected to nixtamalize it, resulting in widespread niacin deficiency. Photo credit: Geoff Lane, Woman with goiter. The fortification of certain foods was designed to prevent nutrient deficiencies in the general population.
In the s, French chemist Jean Boussingault advocated adding iodine to table salt to prevent goiter enlarged thyroid glands , 10 a condition linked to iodine deficiency. Photo credit: Dr.
Bhandari, Contrary to popular belief, the effects of food processing on nutrition are so varied that they cannot be generalized as unhealthy. Some processing techniques deplete nutrients from food. Refining grains, for example, removes the bran and germ, which contain important nutrients like B vitamins, iron, and fiber. Some processing techniques raise nutrient levels by adding vitamins and minerals.
Enrichment is the restoration of some of the nutrients that are lost during processing. Fortification goes a step further, adding nutrients above naturally occurring levels in a food. Food manufacturers may also use fortification as a selling point for foods of questionable nutritional quality, such as candy, snacks, and sweetened breakfast cereals.
The overabundance of such foods in U. Soda and grain-based desserts e. Workers in meat processing plants may be required to use sharp tools and heavy machinery, at high speeds, under crowded conditions, for long hours, and on slippery floors—sometimes without adequate training. Animal processing facilities present opportunities for disease-causing bacteria and other pathogens to enter the food supply. Large-scale poultry processing plants often operate at very high speeds—up to birds per minute—allowing just a fraction of a second to identify and remove contaminated carcasses from the line before they are shipped to stores.
The large volume of carcasses handled by these plants also presents frequent opportunities for cross-contamination. Percentage of sales earned by the four largest corporations in their respective industries. Earnings from animal slaughtering and meat processing have become concentrated among a small number of powerful businesses. In the U. Despite recent improvements, reported injury rates for workers in animal slaughtering and meat processing plants are over 40 percent higher than the average for the private American workforce.
In numerous documented cases, injured plant workers were unable to receive compensation, and injuries caused them to lose their jobs. Animal slaughtering and processing companies frequently hire immigrant workers, who may be less empowered to dispute hazardous working conditions.
In some cases, undocumented immigrants are smuggled into the country by the companies that hire them, and face fears of deportation. These and other threats can deter workers from organizing to collectively bargain for better working conditions, and from reporting safety violations.
Whether they are canned, bottled, boxed, or shrink-wrapped, processed foods are generally sold in packages. Packaging plays important roles in preservation and food safety , serving as a barrier against bacterial contamination, pests, physical damage, the elements, and even curious or malicious tampering by people—damaged packaging alerts consumers that someone may have opened it previously.
Packaging can also make food easier to transport, store, and serve; the spout on a carton of milk, for example, makes it easier to pour. Packaging also provides a surface for displaying labels. For all its benefits, packaging can contribute to public health and environmental problems. Food packaging accounts for roughly two-thirds by volume of total packaging waste in the United States. Manufacturers can also reduce the amount of material used in food packaging, ideally without compromising benefits to consumers.
Some forms of food packaging may also pose health risks among consumers. Bisphenol A BPA , for example, is a synthetic human-made chemical used in the manufacture of hard plastic bottles, linings of metal cans, and various other products. Studies suggest BPA exposure may affect reproductive development in fetuses, infants, and children, among other health concerns. The following list of suggested resources is intended as a starting point for further exploration, and is not in any way comprehensive.
Processing food. Br Med J. Food Processing: Principles and Applications. Ames, Iowa: Wiley-Blackwell; Centers for Disease Control and Prevention. Multi-State Outbreak of E. Pollan M. The Vegetable-Industrial Complex. N Y Times Mag. Robertson GL. Food Packaging: Principles and Practice. CRC Press; Nutritional comparison of fresh, frozen and canned fruits and vegetables.
J Sci Food Agric. Fellows P. Food Processing Technology: Principles and Practice. Food Trends and the Changing Consumer. Paul, Minnesota: Eagan Press;
While the process of fermentation significantly predates the emergence of our species, humans have been harnessing this microbial technology for food production and preservation for thousands of years. Here, we will dive into the history and science of fermented foods. A portion of an ancient Egyptian artifact depicting grape cultivation and winemaking. In the culinary sense, fermentation is the transformation and preservation of food by bacteria. While the process of fermentation as a culinary practice dates back to early human civilization, it took a very long time before the scientific principles were understood 1. The table below highlights a few fermentation milestones in the context of culinary anthropology:. Selected fermentation milestones over human history.
Maillard reaction produces flavour and aroma during cooking process; and it is used almost everywhere from the baking industry to our day to day life to make food tasty. It is often called nonenzymatic browning reaction since it takes place in the absence of enzyme. When foods are being processed or cooked at high temperature, chemical reaction between amino acids and reducing sugars leads to the formation of Maillard reaction products MRPs. Depending on the way the food is being processed, both beneficial and toxic MRPs can be produced. Therefore, there is a need to understand the different types of MRPs and their positive or negative health effects.
History and Biochemistry of Fermented Foods
The term food preservation refers to any one of a number of techniques used to prevent food from spoiling. It includes methods such as canning, pickling, drying and freeze-drying, irradiation, pasteurization, smoking, and the addition of chemical additives. Food preservation has become an increasingly important component of the food industry as fewer people eat foods produced on their own lands, and as consumers expect to be able to purchase and consume foods that are out of season. The various methods that have been devised for preserving foods are all designed to reduce or eliminate one or the other or both of these causative agents.
It is recommended to also follow "Food Biotechnology" by Wilbert Sybesma, since the following 2 courses will alternate every second week on Friday afternoons 4 lessons : "Food Biotechnology" by Wilbert Sybesma and "Chemistry of food processes" by Imre Blank. Attend lectures. Each student will give a 15 minutes presentation during the semester. This presentation will be given alone or as a team, depending on the number of students. Grandison, 2nd ed.
Metrics details. Food preservation involves different food processing steps to maintain food quality at a desired level so that maximum benefits and nutrition values can be achieved. Food preservation methods include growing, harvesting, processing, packaging, and distribution of foods. The key objectives of food preservation are to overcome inappropriate planning in agriculture, to produce value-added products, and to provide variation in diet.
Food processing , any of a variety of operations by which raw foodstuffs are made suitable for consumption , cooking , or storage. A brief treatment of food processing follows. For fuller treatment of storage methods, see food preservation. Food processing generally includes the basic preparation of foods, the alteration of a food product into another form as in making preserves from fruit , and preservation and packaging techniques. A number of food-processing innovations have even resulted in new products, such as concentrated fruit juices, freeze-dried coffee, and instant foods. Foods and food supplements have also been processed from such hitherto untapped sources as oilseeds chiefly protein-rich soybeans and cottonseeds ; mutant varieties of crops; leaves, grasses, and aquatic plants; and highly nutritious fish meal and concentrates.
Food science is the basic science and applied science of food ; its scope starts at overlap with agricultural science and nutrition and leads through the scientific aspects of food safety and food processing , informing the development of food technology. The Institute of Food Technologists defines food science as "the discipline in which the engineering, biological, and physical sciences are used to study the nature of foods, the causes of deterioration, the principles underlying food processing , and the improvement of foods for the consuming public". Activities of food technologists include the development of new food products, design of processes to produce these foods, choice of packaging materials, shelf-life studies, sensory evaluation of products using survey panels or potential consumers, as well as microbiological and chemical testing. Food science brings together multiple scientific disciplines. Food technology incorporates concepts from chemical engineering , for example. Food chemistry is the study of chemical processes and interactions of all biological and non-biological components of foods.
Enzymes in Food Processing Quality Benjamin K. Simpson, Xin Rui, and and anatomy to biochemistry and then down tion, preservation, processing.
Know About the Fermentation of Food
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