/ 



102 SCIENCE PROGRESS 



third definition is, " Cold storage meat is meat from animals 

 recently slaughtered and preserved by refrigeration until 

 delivered to the consumer." * In commenting on this defini- 

 tion, W. D. Richardson points out how unsatisfactory it is. 

 He says : " The every-day distinction and scientific distinction 

 also should be made between chilled meat and frozen meat, 

 the former being held at temperatures of a few degrees above 

 the freezing point until delivered to the consumer, and the 

 latter in the solid frozen condition." s 



It is also interesting to note that there is apparently no 

 other official test for frozen meat than the examination of the 

 blood, the red corpuscles of which have undergone haemolysis 

 in the case of frozen meat. 



Nevertheless, in spite of the fact that the development of 

 the cold storage industry, in so far as it concerns meat, has not 

 been based on scientific research, a certain amount of scientific 

 information having a bearing on the question has been collected. 

 The principal constituents of meat, chemically considered, 

 are water, proteins and fats. The lean of beef and mutton 

 contains about 75 per cent, of water. Of the remaining 25 

 per cent., by far the greater proportion is protein, this amount- 

 ing sometimes to 20 per cent, of the total weight in beef, the 

 remaining 5 per cent, being composed of water-soluble organic 

 substances (about 4 per cent.) and inorganic salts about 1 per 

 cent, of the whole carcass. The relative amount of protein 

 varies considerably in different individuals, especially in rela- 

 tion to the amount of fat, which in mutton may amount to 

 three times the weight of nitrogenous substances. 3 Thus it 

 is to be expected that the problem of preserving meat at low 

 temperatures just above the freezing-point presents difficulties 

 different from those in fruits, where the great proportion of the 

 dry matter is carbohydrate. 



The lean part of meat is composed of muscle fibres which 

 are narrow and thread-like, the bundles of fibres being pene- 

 trated and supported by the connective tissue, which contains 

 the nerves and blood-vessels. After the death of the animal 



1 See W. D. Richardson, " Meat and Meat Products," in Allen's Commercial 

 Organic Analysis, vol. viii. p. 261, London, 1913. 



9 Ibid. 



3 See e.g. A. D. Hall, "The Book of the Rothamsted Experiments." Second 

 Edition, pp. 250-54, London, 1917 ; also W. D. Richardson in Allen's Commercial 

 Organic Analysis, vol. viii. pp. 262-7, London, 1913-* 



