Year: 1941
Type: article
Abstract: Cheddar cheese made from milk to which a small amount of commercial lipase has been added will develop a flavor defect known as rancidity (1, 2).This effect is presumably due to lipolysis of butterfat and the consequent liberation of fatty acids, the lower members of which possess an unpleasant odor (3).Rancidity produced in this manner closely resembles the odor of rancid cheese which occurs occasionally but persistently under factory conditions.It has been suggested that milk lipase may be among the factors concerned in the development of rancidity under commercial conditions (4).Since lipases from various sources would be expected to possess many properties in common, the study of lipase induced rancidity is of interest in connection with the rancid cheese problem.It has been known for some time that lipase is protein in nature ( 5), and that as such it is subject to inactivation by proteolysis (6).These observations have been extended by their application to the study of cheese flavor defects.In this investigation experimental evidence is submitted to show that rennet or pepsin or both inactivate, to some extent, added lipase in cheddar cheese and that the use of higher amounts of these pro teolytic enzymes contributes to flavor improvement of such cheese.F~XPERIMENTAL ~VIilk was obtained from the Experimental Farm herd.Small vats of cheese were made using 240 pounds of milk.This gave two 10-12 lb.cheese to each vat.Cheese were made by an experienced maker according to standard procedures except as otherwise indicated below.They were stored at 60 ° F. until the first grading and then transferred to a second storage held at 48-50 ° F. The cheese were graded at intervals for flavor only by an experienced member of the Dominion Grading Staff.It was first necessary to determine the amount of commercial lipase (Pfanstiehl) which when added to cheese milk would develop rancidity in I0 to 14 days.This was done by making a series of vats of cheese using varying amounts of lipase.It was found that 2.5-5.0 gms. of lipase per I000 pounds of milk gave a satisfactory working level.It was possible to show in preliminary experiments that higher than the
Source: Journal of Dairy Science
Authors: I. Hlynka, E.G. Hood, C.A. Gibson
Institution: Agriculture and Agri-Food Canada
Language: English
Subfield: Agronomy and Crop Science
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W2015545441