and higher degrees of overcook to achieve satisfactory F0 values at the center.

Continuous systems using heat penetration will also have wide variations in F0 values from the center of the particulate to the surface, the variation depending greatly on the size of the particulate, the ratio of solids to liquid (as the carrier fluid must provide the excess heat required to penetrate the particulate), and the sterilization temperature selected.

Fig. 6 and Fig. 7 show the F0 value given to the carrier fluid to achieve a minimal F0 value of 5 in the center of the particulate, and the processing times required at various temperatures. It can be seen that for particulates larger than 10 mm, a considerable wide range of F0 values result

Figure 5. Fluid temperature increases in the holding tube in ohmic heating. Bottom: ohmic column outlet; top: holding tube exit.

important information for the application of regulatory approval of such novel technology.

Challenge tests carried out (on now commercially available products) by the Campden Food and Drink Research Association have involved particulates of meat and vegetable up to 19 mm cube. An average of 10 million spores of Bacillus stearothermophilus per particle embedded in a food/alginate mixture were included in batches of mince and mushrooms in bolognese sauce, and in kidney, peas, and gravy, in order to determine the lethality at the center and throughout particles of various sizes from 3 mm to 19 mm.

The results obtained (Table 1) demonstrate the high level of microbiological security of the process and the very narrow range of lethality from the surface to the center of the particulates.

The cook value (C0) of a process is also a function of time and temperature (dependent upon the viscosity of the product). For small cans, F0 values for viscous products can typically range from 5 to 300 resulting in high cook values. Larger cans will show even greater variations in F0 values

Table 1. Lethality Tests of APV Ohmic System on Bacillus stearothermophilus

Table 1. Lethality Tests of APV Ohmic System on Bacillus stearothermophilus

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Homemade Pet Food Secrets

Homemade Pet Food Secrets

It is a well known fact that homemade food is always a healthier option for pets when compared to the market packed food. The increasing hazards to the health of the pets have made pet owners stick to containment of commercial pet food. The basic fundamentals of health for human beings are applicable for pets also.

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