Effect of temperature and bulk density on thermal conductivity of spray-dried whole milk powder

1. Storage tests have been made independently in two laboratories on four samples of spray-dried whole-milk powder prepared on a Gray-Jensen plant from one batch of milk using pre-heating temperatures of 160 and 190° F. with and without the addition of 0·06–0·08% of ethyl gallate as antioxidant. The powders were packed in lacquered and in plain tinplate containers and stored at 47, 37 and 15° C, and at room temperature. Deterioration was followed by tasting tests, by determination of the amount of oxygen absorbed by the powders and by estimation of peroxide in the fat.2. Raising the pre-heating temperature from 160 to 190° F. or the addition of ethyl gallate to the milk improved the keeping quality of the resulting powder, as measured by taste, by a factor of the order of 1½–2½ at 47° C, of 2–3 at 37° C. and of 3–4 at 15° C. and room temperature.3. Increasing the pre-heating temperature and incorporating ethyl gallate in the milk extended the storage life of the powder by a factor of the order of 3 at 47° C., 4 at 37° C. and 8 at 15° C. and room temperature.4. For an equivalent loss of palatability powder from high-temperature pre-heated milk absorbed appreciably more oxygen than the corresponding powder from low-temperature pre-heated milk, and the gallate-treated samples slightly more than the corresponding control powders.5. The temperature coefficients for deterioration were slightly higher for the high-temperature powders than for the corresponding low-temperaturepowders.6. With the two control powders storage in lacquered tinplate resulted in a small increase, of the order of 10%, in keeping properties as comparedwith storage in plain tinplate. With the ethyl gallate-treated powders no advantage resulted from the use of lacquered tinplate.

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Effects of Morphology on the Bulk Density of Instant Whole Milk Powder

Foods ◽

10.3390/foods9081024 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1024 ◽

Cited By ~ 2

Author(s):

Haohan Ding ◽

Bing Li ◽

Irina Boiarkina ◽

David I. Wilson ◽

Wei Yu ◽

...

Keyword(s):

Particle Size ◽

Physical Properties ◽

Bulk Density ◽

Size Range ◽

Milk Powder ◽

Particle Size Range ◽

Shape Factors ◽

Whole Milk ◽

Powder Samples ◽

Whole Milk Powder

The chemical and physical properties of instant whole milk powder (IWMP), such as morphology, protein content, and particle size, can affect its functionality and performance. Bulk density, which directly determines the packing cost and transportation cost of milk powder, is one of the most important functional properties of IWMP, and it is mainly affected by physical properties, e.g., morphology and particle size. This work quantified the relationship between morphology and bulk density of IWMP and developed a predictive model of bulk density for IWMP. To obtain milk powder samples with different particle size fractions, IWMP samples of four different brands were sieved into three different particle size range groups, before using the simplex-centroid design (SCD) method to remix the milk powder samples. The bulk densities of these remixed milk powder samples were then measured by tap testing, and the particles’ shape factors were extracted by light microscopy and image processing. The number of variables was decreased by principal component analysis and partial least squares models and artificial neural network models were built to predict the bulk density of IWMP. It was found that different brands of IWMP have different morphology, and the bulk density trends versus the shape factor changes were similar for the different particle size range groups. Finally, prediction models for bulk density were developed by using the shape factors and particle size range fractions of the IWMP samples. The good results of these models proved that predicting the bulk density of IWMP by using shape factors and particle size range fractions is achievable and could be used as a model for online model-based process monitoring.

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A Spectrophotometric Study of the Changes inPeroxide Value of Spray-Dried Whole Milk Powder during Storage

Journal of Dairy Science ◽

10.3168/jds.s0022-0302(46)92437-x ◽

1946 ◽

Vol 29 (1) ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Harry Pyenson ◽

P.H. Tracy

Keyword(s):

Milk Powder ◽

Spectrophotometric Study ◽

Whole Milk ◽

Whole Milk Powder ◽

Spray Dried

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Effect of Sucrose on Physical Properties of Spray-Dried Whole Milk Powder

Journal of Food Science ◽

10.1111/j.1750-3841.2008.00955.x ◽

2008 ◽

Vol 73 (9) ◽

pp. E431-E438 ◽

Cited By ~ 1

Author(s):

U.V. Lay Ma ◽

G.R. Ziegler ◽

J.D. Floros

Keyword(s):

Physical Properties ◽

Milk Powder ◽

Whole Milk ◽

Whole Milk Powder ◽

Spray Dried

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283. The keeping qualities of milk powders: Part I. Addition of antioxidants

Journal of Dairy Research ◽

10.1017/s0022029900003526 ◽

1941 ◽

Vol 12 (2) ◽

pp. 178-183 ◽

Cited By ~ 8

Author(s):

R. Waite

Keyword(s):

Milk Powder ◽

Resultant Powder ◽

Butter Fat ◽

Whole Milk ◽

Effective Antioxidant ◽

Oat Flour ◽

Reconstituted Milk ◽

Whole Milk Powder ◽

Spray Dried

1. Hydroquinone is an effective antioxidant for the butter-fat of spray-dried whole-milk powder, but in a concentration equivalent to 0·5% of the weight of fat (0·12% on the weight of powder) it produces an objectionable ‘metallic’ flavour in the powder and reconstituted milk.2. Oat flour is much less efficient than hydroquinone as an antioxidant but 0·25% added to the milk, preferably before condensing, increases the resistance of the resultant powder to the development of tallowiness by the equivalent of about 4 months at normal temperatures. Raising the concentration of oat flour to 0·5% approximately doubles this increase but at the same time imparts a noticeable oat flavour to the powder.

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The flow of nutrients from the abomasum in calves fed on heat-treated milks

Australian Journal of Agricultural Research ◽

10.1071/ar9760903 ◽

1976 ◽

Vol 27 (6) ◽

pp. 903 ◽

Cited By ~ 9

Author(s):

RJ Johnson ◽

J Leibholz

Keyword(s):

Milk Powder ◽

High Heat ◽

Once Daily ◽

Fresh Milk ◽

Bull Calves ◽

Heat Treated ◽

Whole Milk ◽

Whole Milk Powder ◽

Hydrolysis Of ◽

Spray Dried

Three Friesian bull calves were fitted with re-entrant duodenal cannulae within the first week of life. Within 2 days of surgery the calves were allotted to one of four experimental diets: (1) fresh milk; (2) spray-dried low-heat whole milk powder (LS); (3) spray-dried high-heat whole milk powder (HS); (4) roller-dried whole milk powder (RD). At weekly intervals the calves were reallotted to another diet at random, so that each calf was fed for 1 week on each diet. The flow of digesta from the abomasum decreased as the time after feeding increased. When calves were fed once daily on the severely heat-treated milks (HS and RD), a more rapid flow of nutrients from the abomasum occurred in the first 12 hr after feeding, and a lower flow between 12 and 24 hr after feeding, than when they were given fresh milk or the LS milk. In the first 6 hr after feeding calves on fresh milk or LS milk a greater proportion of the casein nitrogen tended to be hydrolysed in the abomasum than in those fed on the HS milk. Subsequently the situation was reversed. The hydrolysis of fats in the abomasum was greater when the calves were given the severely heat-treated milks (HS and RD) than when they were fed on the other milks. Many of the changes observed may be related to the density of the milk clot formed in the abomasum.

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341. The effect of the pre-heating temperature on the bacterial count and storage life of whole milk powder spray-dried by the Krause process

Journal of Dairy Research ◽

10.1017/s0022029900004829 ◽

1946 ◽

Vol 14 (3) ◽

pp. 378-399 ◽

Cited By ~ 29

Author(s):

J. D. Findlay ◽

Constance Higginbottom ◽

J. A. B. Smith

Keyword(s):

Room Temperature ◽

Heating Temperature ◽

Milk Powder ◽

Bacterial Count ◽

Strong Reaction ◽

Whole Milk ◽

Whole Milk Powder ◽

And Storage ◽

Spray Dried

1. Storage tests on spray-dried full-cream milk powders prepared from milk preheated at 160,170,180, 190 and 200° F. for approximately 20 sec. and dried by the Krause process have been carried out at 47, 37 and 15° C. or room temperature. The storage tests were carried out independently at two different research stations. At the Hannah Institute the powders were packed in plain tin-plate containers as received from the factory. At Cambridge grease-free plain tin-plate and lacquered tin-plate containers were used. Deterioration was followed at both stations by a tasting panel and by determination of the amount of oxygen absorbed by the powder and of the accumulation of peroxide in the fat.2. When fresh the powder pre-heated at 180° F. had the best flavour, followed in order of preference by those pre-heated at 190 and 200° F., which had a definite but quite pleasant ‘boiled’ or ‘cooked’ flavour, and by those pre-heated at 160 and 170° F. which had an incipient tallowy flavour, but were nevertheless still acceptable. The 200 and 190° F. powders gave a strong reaction for volatile sulphur, the 180° F. powder a much weaker but quite definite reaction, and the 170 and 160° F. powders a negative reaction. The copper content of the 180° F. powder which, with the 170° F. sample, was the highest of the group, may have been partly responsible for the weakness of the reaction for volatile sulphur given by this sample. The solubility of the 180, 190 and 200° F. powders was not adversely affected by the high pre-heating temperatures, and the moisture contents of all the powders were sufficiently low to prevent any obvious loss of solubility, which remained very good indeed throughout the storage tests.

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