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  DNA Barcoding Methodologies for the Identification of Fish Species in Cooked Products

  Rosalee S. Hellberg

  Deoxyribonucleic acid (DNA) barcoding is a sequencing-based method that utilizes a standardized genetic region to identify species in combination with a reference database. DNA barcoding methodologies have been extensively applied to the identification of species in cooked seafood. While the typical genetic target associated with DNA barcoding is a ~650-bp region of the gene coding for cytochrome (cyt) c oxidase subunit I (COI), additional genetic targets include partial regions of the cyt b and 16S ribosomal ribonucleic acid (rRNA) genes. Most categories of cooked seafood can be identified using ~400- to 700-bp regions of these genes; however, canned seafood and other heavily processed products often require shorter regions of DNA, termed “mini-barcodes.” Metabarcoding is an emerging technique that allows for the identification of seafood species mixtures. The objective of this book chapter was to provide an overview of the application of DNA barcoding methodologies for the identification of seafood species in cooked products.

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  What is the Benefit of Irradiation Compared to Other Methods of Food Preservation?

  Anuradha Prakash

  "Commercially available food products are processed using a range of technologies ranging from as minimal as cleaning and peeling to extensive processing involving multiple treatments to meet consumer preferences in terms of sensory attributes, price, or lifestyle needs and to extend shelf-life and/or assure safety. Conventional methods include thermal processing, dehydration, refrigeration and freezing, and extrusion. Consumers are increasingly interested in products that are minimally processed and formulated without chemical preservatives, and the food industry has responded by deveoping nonthermal technologies such as high-pressure processing (HPP), pulsed electric field (PEF), and thermal technologies such as ohmic heating, which maximize retention of quality and nutrition while achieving pasteurization goals. In fact, processors have available an arsenal of food processing technologies that singly or in combination can be used to preserve food products. Many products are preserved using a hurdle approach, where several sublethal treatments, such as mild heat, refrigeration, pH control, water activity, and redox potential, used in combination, can effectively suppress microbial growth."

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  Irradiation of Fruits and Vegetables

  Anuradha Prakash and José de Jesús Ornelas-Paz

  "Radiation is any energy traveling through the space in form of waves or particles. It can be classified as ionizing and nonionizing, depending on its energy. Ionizing energy has shorter wavelengths yet higher frequency and energy as compared to nonionizing energy... The term 'food irradiation' refers to the deliberate exposure of food to ionizing radiation."