Studies on Butter Salts

Abstract

Ten leading butter salts, representing three flake salts and seven cube salts, were studied with reference to their physical, chemical, and bacterial properties as related to their effect on flavor, body, texture, and color of butter. Some of the salts were badly caked in the barrel while others were free-flowing. The most freely flowing salts were those that showed the greatest freedom from chemical impurities and that were lowest in moisture content. Numerous tests showed that the drier the salt the less its tendency to lump. As the moisture content of the salt increases the salts lose their free-flowing property and cake profusely. For similar reasons the presence in salt of calcium chloride and magnesium chloride, which are highly deliquescent, diminishes the free-flowing property of the salt and causes it to lump. The flake salts were found to be considerably more bulky than the cube salts. Taking the weight of a given volume of water as one, the weight of the flake salts averaged 0.86 and of the cube salts 1.26. With the weight of the commercial package of salt standardized to 280 pounds per barrel, the barrel for cube salt need be only two-thirds as large as the barrel for flake salt. Several of the salts contained foreign matter in sufficient amounts to produce a very turbid brine and dirty color when dissolved in water. Such salts are objectionable, particularly when intended for use in the preparation of brine for the treatment of parchment liners, circles, and wrappers. The salts in the original containers were found to be bacteriologically clean. The bacterial counts ranged from less than one colony per gram of salt to seven colonies, averaging from 2 to 3 colonies for all salts. Unless contaminated in the creamery after the barrel is opened, due to improper storing or handling, these salts may be considered entirely negative as a possible source of bacterial contamination of butter. The great majority of the crystals in each salt passed through 40 and 60 mesh screens. The flake salt showed a considerably coarser grain and a wider range of crystal size than the cube salt. Thus, of the flake salts about 60 per cent of the crystals passed through 40 and 60 mesh screens while 27 per cent required a coarser screen. Of the cube salts, approximately 90 per cent of the crystals passed through the 40 and 60 mesh screens while only 1.7 per cent required a coarser screen. The ten salts were very similar in their rates of solution. During the first twenty seconds there was a tendency for the flake salts to show slightly greater rapidity of solution than the cube salts but at the end of twenty-five seconds the amount of salt dissolved averaged the same for both types of crystals. At the end of two minutes the solution of each salt was complete. After the first five seconds each liquid contained 19.75 per cent or more of salt in solution. This salt concentration is fully equal to the strength of the brine in butter containing 3 per cent salt. This rapidity of solution of each of the ten salts suggests that such minute differences in solubility rate as were observed between individual brands and between the two types of salt are too slight to be of any significance from the standpoint of preference for any one salt in butter manufacture. The percentage of sodium chloride in the 10 salts, as determined by direct analysis, ranged from 98.34 to 99.69 per cent, averaging 99.14 per cent. The sodium chloride content as determined by difference ranged from 98.59 to 99.94 per cent. Phosphates and barium salts were entirely absent in all salts. The largest chemical impurity consisted of calcium sulphate ranging from 0.01 to 1.225 per cent. Small amounts of calcium and magnesium chlorides, magnesium and sodium sulphates, and calcium and magnesium carbonates, and traces of iron, were also present. The insoluble matter ranged from 0.003 to 0.031 per cent and the moisture from 0.005 to 0.14 per cent. When working these salts into butter, both under experimental conditions and in commercial manufacture, no differences in flavor, body, texture, and color could be detected in the finished butter. Likewise, the addition to the pure salt of impurities in relatively large amounts, such as 2 per cent CaSO4, 3 per cent KCl, 1 per cent CaCl2, and 1 per cent MgCl2, failed to have any noticeable effect on the flavor of the butter. These findings suggest that, while chemical purity in butter salts is highly desirable, such small amounts of chemical impurities as are found in the above standard butter salts are incapable of impairing or changing the quality of butter. © 1928, American Dairy Science Association. All rights reserved.