SOME OBSERVATIONS ON THE MODIFICATION OF FREEZE DEHYDRATED MEAT^a,b

Abstract

Studies on the biochemistry of meat during post niortem aging has shown that the muscle plasma plays an important role in the changes in the chemical and physical properties of the meat (6,15,16,17,25,26, 27,25). Arnold et al. (3) reported that during post niortem aging, sodium and calcium were continuously released by the muscle protein while potassium was absorbed after the first 24 hours. They also stated that the cationic shifts during post mortem ging appears to increase the electrical charge of the protein molecules of meat esulting in a measurable increase of hydration accompanied by improved mderness. N'ierbicki et al. (26,29) established that the water holding capac-.y of meat may be altered by modifying the ionic atmosphere in meat. Again hese authors (29,30) stated that ion protein interactions are taking place uring post niortem aging of meat and also during cooking process. Preparations, properties, and histological, histochemical and some chemical haracteristics of freeze-dehydrated meat have been described (7,19,20,21, '2). Harper and Tappel ( 2 4 ) stated that the texture of the freeze-dried meat s drier than the frozen control and that this dry texture is one of the principal iroblenis which remains to be solved in the field of lyophilization of meat.The studies to be reported here were directed to an improvement in the 'euture and toughness of cooked reconstituted freeze-dehydrated meat. Since the rehydrated meat tends to be tough and woody upon cooking, it was thought 'hat modification of meat through vascular infusion of various salts to improve the water holding properties of the muscle protein prior to freeze-dehydration might be carried over to the cooked rehydrated meat and thereby improve the acceptability of the product. In order to evaluate the effect of modification of the meat it was also necessary to study in some detail the relationship of post mortem aging and of cooking prior to freeze-dehydration to the quality of the meat as eaten. MATERIALS A N D M E T H O D STwenty-eight cattle were used in this work; most of them were comparable to lower half of U. S. good grade. The sampling techniques and methods used have been previously reported from this laboratory (3,6,17,28,29).Modification of meat: Three different methods were used for modification of meat under investigation : 1 ) Modificatiolt of groztnd meat: Aliquot samples of ground meat were weighed and modifier solutions were added to the ground meat using one part of additive to 10 '

Effect of Mode of Rehydration on Textural Parameters of Precooked Freeze‐dried Sliced Beef*

“…This study was undertaken to determine the effect of the rehydration procedure on microscopic appearance and textural characteristics of precooked freeze-dried sliced bovine meat. The rate of moisture release on chewing was of special interest, as freeze-dried meat is known to have a poor water holding capacity and a dry mouth feel (Tappel et al, 1955;Hamdy et al, 1959). The study was performed as part of a more comprehensive research on fundamental aspects of meat texture and on objective methods of description and quantification of textural characteristics.…”

INFLUENCE OF FREEZING AND THAWING ON HYDRATION AND CHARGES OF THE MUSCLE PROTEINSa

“…In the present paper these methods are used to determine whether freezing and thawing cause denaturation. This problem was of interest because of the undesirable changes in meat proteins brought about by freeze drying (10). In this process the meat is frozen before drying and the question arises whether changes caused by freeze drying are due to the freezing procedure itself or to other factors.It is known that freezing immediately after slaughter presents special problems because of the presence of adenosinetriphosphate (ATP) and the accelerated decomposition of the ATP during thawing resulting in "thaw rigor."…”

CHANGES IN HVDRATION AND CHARGES OF MUFCLE PROTEINS, DURING FREEZE‐DEHYDRATION OF MEATa

“…The texture of lybphilized and rehydrated meat is drier than the frozen control (17). The decrease of tenderness and juiciness produced by freeze-drying apparently is caused by a loss of the water-holding capacity of muscle proteins (3,7). Hamdy et al (7) pointed out that the dry texture and the decrease of meat hydration is one of the principal problems in the field of lyophilization of meat.…”