摘要:

The quantity of drip obtained from meat frozen at a constant rate is affected by the period between slaughter and freezing, and the pH of the tissue. These two factors appear to act independently, and only the latter was studied extensively. In precooled meats the maximum amount of drip was obtained at about pH 5.2, and as the pH increased the net drip decreased to zero at about pH 6.4. Pork, beef and mutton behave similarly both with respect to the form of the drip-pH relation and the quantity of drip exuded at a given acidity. Beef is normally more acid than the other meats tested, and this can account for its greater tendency to drip in commercial practice.Microscopic studies showed that large crystals were always produced by slow-freezing, regardless of the pH of the material. The absence of drip from slowly frozen tissue at pH 6.4 is therefore not due to crystal size, but must be attributed to the greater re-absorbing power of the proteins in this region. Protein denaturation does not affect the quantity of drip obtained when meat is slowly frozen or stored for periods up to three days in the freezing zone. The weak re-absorptive power of the proteins at pH 5.2 must be attributed to their isoelectric condition in this region, rather than to their denaturation. It is only in this isoelectric region that the production of small crystals by quick-freezing will reduce the quantity of drip.

ISSN:1923-4287    

DOI:10.1139/cjr38d-016

出版商:NRC Research Press    

年代:1938

数据来源: NRC

摘要:

Eight species were found. One,Stephanoprora mergi, is described as new, andEchinoparyphium elegansandPsilochasmus longicirratusare here recorded for the first time in America. Several species are described from new hosts. The other specimens recorded areEchinostoma revolutum,Hypoderaeum conoideum,Zygocotyle lunata,Apatemon gracilis, andNotocotylus attenuatus.

ISSN:1923-4287    

DOI:10.1139/cjr38d-017

出版商:NRC Research Press    

年代:1938

数据来源: NRC