The effect of heat treatment on blood : a thesis presented in partial fulfilment of the requirements for the degree of Master of Food Technology in Product Development and Marketing at Massey University, Palmerston North, New Zealand

Abstract

New Zealand is a meat producing and exporting country and therefore has a large meat processing industry. In any industry, the utilisation of waste materials from the production of the main product as "byproducts" aids in the reduction of the manufacturing costs of the primary product, because of increased utilisation of overheads, and results in increased profit. During the processing of animal carcases to produce meat, a large amount of waste materials, including offal, skins, hooves, bones and blood, is produced. One of these waste materials, blood, is drained from the animals immediately after their slaughter and is available in large quantities as a raw material for the production of byproducts. Besides the reduction of meat processing costs, the recovery of blood solids considerably reduces the effluent load of the processing plant, blood solids being mainly organic matter. Unfortunately this latter consideration, i.e. the reduction of the Biological Oxygen Demand of the effluent from meat processing plants, is often the prime consideration in blood processing in New Zealand, as the cost of recovery may exceed the value of the final product; the quality and therefore value of blood products being of little importance. The major products produced from whole blood are animal feedstuffs (blood meal) and fertiliser (dried blood, and blood and bone), although blood may be processed into black puddings, or utilised as a protein binder in sausage manufacture. Blood is also processed by separating the red corpuscles from the plasma, and manufacturing edible and pharmaceutical products from these separated fractions. This improves the value of the final products obtained from blood, but the advantage of this refinement in processing would depend on the cost of the separation process and the individual processing of the two fractions; this would depend to a large extent upon the throughput of the plant. [From Introduction]