Thermal processing of food

Lewis, M. and Fleppell, N. (2000). Continuous Thermal Processing of Foods—Pasteurization and UFIT Sterilization. Aspen Publishers Inc., Gaithersburg, MD. 

Temperature conditions during thermal processing of foods. 

M. Lewis and N. Heppell, Continuous Thermal Processing of Foods — Pasteurisation and UHT Sterilisation, Aspen Publishers, New York, 2000. 

T. Hofmann, W. Bors, and K. Stettmaier, Radical-assisted melanoidin formation during thermal processing of foods as well as under physiological conditions, J. Agric. Food Chem., 1999, 47, 391-396. 

K. P. Nott and L. D. Hall, New techniques for measuring and validating thermal processes, in P. Richardson, (Ed.), Improving the Thermal Processing of Foods, Part 4, Woodhead Publishing Limited, Cambridge, UK, 2004, pp. 385 -07. 

Thermal processing of food by conduction heating Simultaneous minimization of surface cook values (i.e. maximization of final product quality) and minimization of processing time. GA An artificial neural network model was developed based on simulated data from the first principles model, and then used in optimization. Chen and Ramaswamy (2002)... 

Improving the thermal processing of foods Edited by P. Richardson... 

Should it become necessary, control of Bacillus sp. most likely will prove challenging. The bacterial endospore is nature s most resistant structure. It evolved as a survival method and is resistant to dessication, heat, chemical preservatives, and sterilants. For example, clostridial endospores are used as the basis for establishing time and temperature relationships in the thermal processing of foods. In this regard, Boulton, et al. (1995) reports that endospores of Bacillus sp. are resistant to 70°C (158°F) for 10 min and 95% ethanol for 20 min. They further note that the relative susceptibility to wine preservatives and sterilants is not known. 

The thermal processing of food products, in general, involves heat transfer into the food from hot surroundings, the driving force being the temperature difference between... 

My cotoxins in food Detection and control Edited by N. Magan and M. Olsen Improving the thermal processing of foods Edited by P Richardson... 

The denaturation of proteins does not just occur during thermal processing of foods, but also can be the result of low temperatures (when food is exposed to freezing temperatures of between 0 and -15 °C). As a result, crystals of ice are produced, which can break the cell membranes, followed by denaturation due to surface phenomena at the interface of the two phases (protein solution and ice crystals), or possibly due to the freezing of water needed to maintain the native conformation of the protein. Loss of water also leads to an increase in the salt concentration and osmotic pressure, which can accelerate protein denaturation. Lipoproteins are particularly sensitive to denaturation (e.g. those in egg yolk). The extent of the denaturation is Umited in rapid freezing at very low temperatures, however, as smaller ice crystals are formed. 

Free cystine is relatively stable at temperatures around 100 °C. The reaction that is observable during thermal processing of foods at temperatures of approximately 100 °C is partial elimination of hydrogen sulfide from bound cystine, which is often called protein desulfuration (Figure 2.51). This reaction splits the disulfide bridges in protein with the formation of cysteine and sulfenic acid... 

This chapter on saccharides is divided into two main parts. The first part describes major monosaccharides, and their functional derivatives, oligosaccharides and polysaccharides. Their structure and nomenclature, occurrence in major food commodities, properties and importance in human physiology and nutrition, recommended intake and use in food technology are all described. The second part is devoted to reactions of saccharides that lead to the formation of products that influence odour, taste and colour of foods, and to reactions taking place during storage and thermal processing of food raw materials and foods. 

Riboflavin is very stable during the thermal processing of foods, but decomposes when exposed to Hght. To prevent the photochemical degradation of riboflavin, foods containing higher amounts of riboflavin should not be exposed to direct sunhght, and should be stored in opaque or coloured containers. 

Heterocyclic compounds are formed mainly in non-enzymatic browning reactions, especially in food surface layers during the thermal processing of foods by baking, frying and roasting. They also arise by pyrolysis of proteins, carbohydrates, lipids and other food components some heterocyclic compounds result from reactions catalysed by enzymes. 

Chemical markers can mimic other processes. Chemical reactions taking place in foods can be used to mimic an entirely different process taking place in the vicinity of the site where the chemical measurements are made. An interesting example is the use of chemical markers to determine lethality within a food particulate where direct temperature measurement is not practical (Chapter 6). It appears that chemical reactions can mimic bacterial destruction, and are potentially useful time-temperature integrators in the continuous thermal processing of foods. 

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