171. The effect of commercial sterilization on the nutritive value of milk. IIa. biological value and digestibility of the proteins (nitrogen) of milk

1938 ◽  
Vol 9 (1) ◽  
pp. 6-11 ◽  
Author(s):  
K. M. Henry ◽  
S. K. Kon
Keyword(s):  
Heat Treatment ◽  
Nutritive Value ◽  
Statistical Tests ◽  
Raw Milk ◽  
Biological Value ◽  
True Digestibility ◽  
The Difference ◽  
Sterilized Milk

1. The biological values and true digestibilities of the proteins of raw and commercially sterilized milks from the same bulk have been compared on rats by the method of Mitchell.2. For raw milk a biological value of 84·3 and a true digestibility of 96·4 were obtained, while the figures for sterilized milk were 79·1 and 95·3 respectively.3. Statistical tests showed that the difference in true digestibility was not significant but that the lowering of the biological value by about 6% could be ascribed to the effect of the heat treatment, the odds against chance factors being 625: 1.

173. The effect of commercial sterilization on the nutritive value of milk. III. Effect on the vitamin A and carotene content of milk

1938 ◽  
Vol 9 (1) ◽  
pp. 17-21 ◽  
Author(s):  
A. E. Gillam ◽  
K. M. Henry ◽  
S. K. Kon ◽  
P. White
Keyword(s):  
Heat Treatment ◽  
Vitamin A ◽  
Nutritive Value ◽  
Colorimetric Method ◽  
Raw Milk ◽  
Carotene Content ◽  
Lovibond Tintometer ◽  
Ether Extraction ◽  
Sterilized Milk

1. The vitamin A and carotene content of raw milk have been compared with that of milk from the same bulk after it had been commercially sterilized.2. For this purpose the fat was obtained by ether extraction from eleven samples of raw milk and from eleven corresponding samples of sterilized milk. As the sterilized milk had been previously homogenized it was not possible to churn it.3. The vitamin A and carotene content was estimated by colorimetric (Lovibond tintometer) and by spectrophotometric tests.3. The vitamin A and carotene content was estimated by colorimetric (Lovibond tintometer) and by spectrophotometric tests.4. The results showed that the efiect of the heat treatment was negligible, neither method demonstrating a loss in vitamin A, while for carotene only the colorimetric method indicated a loss of about 2 %.5. The vitamin A and carotene contents of sterilized milk were not decreased after storage for several weeks in a cool dark place.

190. The effect of commercial sterilization on the nutritive value of milk. VII. Conclusions

1938 ◽  
Vol 9 (2) ◽  
pp. 207-207 ◽  
Author(s):  
S. K. Kon
Keyword(s):  
Heat Treatment ◽  
Amino Acids ◽  
Nutritive Value ◽  
Essential Amino Acids ◽  
Limiting Factor ◽  
Vitamin B ◽  
Anaerobic Conditions ◽  
Biological Value ◽  
Sterilized Milk ◽  
Partial Destruction

The work carried out by us on the nutritive value of commercially sterilized milk shows definitely that certain factors are injured in the course of the heat treatment. The biological value of the proteins is slightly but unmistakably decreased, most probably because of the partial destruction of one or more essential amino-acids. Of the vitamins, vitamin C is the most markedly affected. It is decreased by half and, in view of the severity of the heat treatment, it is remarkable that the loss is not greater. The anaerobic conditions which exist during the application of the highest sterilizing temperatures may account for the survival of a part of this labile factor. Vitamin B1 also suffers serious loss, the destruction amounting to 30 % of the original value. Neither vitamin A and carotene nor vitamin B2 (flavin) are affected by the heat treatment. The fate of other components of milk was not studied by us, but experiments on rats on the effect of sterilization on the total nutritive value of milk indicates that vitamin B1 was the first limiting factor of sterilized milk.

226. The effect of commercial drying and evaporation on the nutritive properties of milk

1939 ◽  
Vol 10 (2) ◽  
pp. 272-293 ◽  
Author(s):  
K. M. Henry ◽  
J. Houston ◽  
S. K. Kon ◽  
L. W. Osborne
Keyword(s):  
Raw Milk ◽  
Vitamin B ◽  
Chemical Methods ◽  
Biological Value ◽  
Significant Difference ◽  
True Digestibility ◽  
Growth Promoting ◽  
The Difference ◽  
Physical And Chemical ◽  
Spray Dried

1. Spray-dried (Kestner process), roller-dried and evaporated milks were prepared commercially from one batch of raw milk.2. The biological value of the proteins (nitrogen), vitamin B1 and the growth-promoting properties of the milks were measured by tests on rats.3. Vitamin A and carotene, riboflavin and vitamin C were measured by physical and chemical methods at intervals in the course of storage for a year.4. No significant difference was found between the biological values of the proteins (nitrogen) of the processed milks. The values ranged from 80 for evaporated milk to 84 for spray-dried milk.5. The proteins (nitrogen) of evaporated milk were significantly less digestible (true digestibility 91) than those of spray-dried milk (true digestibility 94). The difference between either of those and roller-dried milk (true digestibility 93) was not significant.

Nutritive properties of freshly prepared and stored evaporated milks manufactured by a normal commercial procedure or by reduced thermal processes in the presence of nisin

1964 ◽  
Vol 31 (1) ◽  
pp. 113-119 ◽  
Author(s):  
Margaret E. Gregory ◽  
Kathleen M. Henry ◽  
S. K. Kon
Keyword(s):  
Nicotinic Acid ◽  
Room Temperature ◽  
Nutritive Value ◽  
Pantothenic Acid ◽  
Raw Milk ◽  
Maximum Temperature ◽  
Vitamin B ◽  
Thermal Processes ◽  
Biological Value ◽  
True Digestibility

SummaryFrom a batch of raw milk, evaporated milk was prepared commercially by 3 procedures: A, a normal commercial procedure involving holding the filled cans at a maximum temperature of 113 °C for 15 min; B, with nisin added and holding at a maximum temperature of 105 °C for 15 min; C, with nisin added and holding at a maximum temperature of 113 °C for 3 min. The content of B vitamins in the raw and evaporated milks was measured microbiologically; the nutritive value of the proteins was determined in rat tests.In milk A, 83% of the vitamin B12, 38% of the vitamin B6 and 20% of the thiamine were destroyed during processing. In milk B, the losses were 67, 30 and 19%, respectively, only the loss of vitamin B12 being significantly lower than in milk A. In milk C, the losses were 67, 23 and 14%, respectively, each of them being significantly lower than in milk A. There was no further loss of thiamine on storage of the milks for 12 months at 4 °C, but at room temperature and at 37 °C further losses occurred in all the milks. Similarly, the vitamin B6 activity of the milks decreased on storage, the loss being greatest at 37 °C, but also detectable at 4 °C. No change in the vitamin B12 content occurred on storage, and no losses of biotin, nicotinic acid, pantothenic acid or riboflavin were detected during manufacture or storage of the evaporated milks.The biological value and true digestibility of the proteins of the evaporated milks were slightly lower than for the raw milk. Neither nisin treatment nor storage at room temperature for a year affected these characteristics.

189. The effect of commercial sterilization on the nutritive value of milk. VI. Comparison of the total nutritive value of raw and commercially sterilized milks

1938 ◽  
Vol 9 (2) ◽  
pp. 188-206 ◽  
Author(s):  
K. M. Henry ◽  
E. W. Ikin ◽  
S. K. Kon
Keyword(s):  
Nutritive Value ◽  
Basal Diet ◽  
Raw Milk ◽  
Cane Sugar ◽  
Male Rats ◽  
Limiting Factor ◽  
Protein Energy ◽  
Preceding Experiment ◽  
The Difference ◽  
Sterilized Milk

1. The effect of commercial sterilization on the total nutritive value of milk was studied in five separate experiments.2. In the first experiment raw and sterilized milks supplemented with minerals were given in equal amounts to pairs of litter-mate male rats. No differences were found in the growth performance of the rats, but the rats on sterilized milk consumed it more readily than their mates on raw milk. This difference was statistically significant.3. Rats getting limited but equal amounts of milk in addition to a basal diet which supplied only protein, energy and minerals grew better on raw than on sterilized milk.4. When the basal diet contained in addition 5% brewer's yeast and the milk intakes were the same as in the previous experiment no difference was found between the two groups.5. Rats receiving raw milk to which 15 g. of cane sugar was added per 100 ml. grew better than rats receiving equal quantities of similarly treated sterilized milk.6. Rats given raw milk containing 30 g. per 100 ml. of sugar grew as well as the rats on sterilized milk in the preceding experiment, but rats receiving similarly treated sterilized milk took much less milk than the raw milk rats, grew very poorly and some of them developed symptoms of beri-beri.7. The difference between raw and sterilized milk is discussed and it is concluded that in these experiments on the total nutritive value of milk vitamin B1 was the first limiting factor of sterilized milk.

scholarly journals The nutritive value of rumen micro-organisms in ruminants

1983 ◽  
Vol 50 (2) ◽  
pp. 471-478 ◽  
Author(s):  
E. Storm ◽  
E. R. Ørskov ◽  
R. Smart
Keyword(s):  
Nutritive Value ◽  
Live Weight ◽  
N Balance ◽  
Biological Value ◽  
Energy Inputs ◽  
N Input ◽  
True Digestibility ◽  
Gross Energy ◽  
Micro Organisms

Four experiments were conducted with eighteen lambs sustained entirely by intragastric nutrition at gross energy inputs varying from 430 to 860 kJ/kg live weight0·75 (W0·75). Isolated rumen micro-organisms (RMO) were infused into the abomasum in quantities varying from 0 to 2 g digestible N/kg W0·75 to assess the increase in N balance as a result of increasing RMO input when N was limiting.The over-all utilization of N from RMO (RMO-N) could be described by the equation y = 0·543 x −0·457, residual SD = 0·037, where y is the N balance and x is the abomasal input of RMO-N, both expressed in g/kg W0·75. Thus the coefficient of efficiency of utilization of infused RMO-N was 0·543 (SE 0·008). The coefficient of efficiency of utilization of RMO-N truly digested (i.e. the biological value) was 0·659 (SE 0·015).The RMO-N input (mean with SE) at N equilibrium was 0·843 (0·009) g/kg W0·75. The true digestibility of RMO-N was 0·813 (0·004). The urinary N excretion when no N was infused was 0·329 (0·008) g/kg W0·75 and the N excreted via the faeces with zero N input was 0·036 (0·009) g/kg W0·75.

170. The effect of commercial sterilization on the nutritive value of milk

1938 ◽  
Vol 9 (1) ◽  
pp. 1-5 ◽  
Author(s):  
S. K. Kon ◽  
K. M. Henry ◽  
E. W. Ikin ◽  
A. E. Gillam ◽  
P. White
Keyword(s):  
Heat Treatment ◽  
Nutritive Value ◽  
Legal Definition ◽  
Previous Communication ◽  
Nutritional Effects ◽  
Definition Of ◽  
Sterilized Milk

We have dealt in a previous communication (1) with the effects-of commercial pasteurization on the nutritive value of milk. We present here the results of an enquiry into the nutritional effects of the more drastic heat treatment to which milk is subjected during commercial sterilization. There is no legal definition of either sterilized milk or of the process of sterilization, but in commerce it is customary to apply the term to milk which has been heated to at least 212° F. for varying lengths of time.

172. The effect of commercial sterilization on the nutritive value of milk. IIb. A note on the effect of the method of feeding dried skimmed milk on the biological value of its proteins

1938 ◽  
Vol 9 (1) ◽  
pp. 12-16 ◽  
Author(s):  
K. M. Henry ◽  
E. W. Ikin ◽  
S. K. Kon
Keyword(s):  
Nutritive Value ◽  
Biological Value ◽  
Liquid Milk ◽  
Skimmed Milk ◽  
The Difference ◽  
Spray Dried

1. In experiments in which the biological value of the proteins was measured spray dried skimmed milk was fed separately from or mixed with a basal “nitrogen free” diet.2. At a 6·9% level of protein (N x 6·38) intake the first method of feeding yielded a biological value of 87·2, the second of 90·3. The difference was not statistically significant (odds of 9: 1 against chance factors).3. The findings do not account for the low biological value reported by us previously for the proteins of raw liquid milk.

The influence of pH and heat treatment on the colour and stability of ultra-high-temperature sterilized milk

1971 ◽  
Vol 38 (3) ◽  
pp. 393-401 ◽  
Author(s):  
J. G. Zadow
Keyword(s):  
Heat Treatment ◽  
Sodium Citrate ◽  
Whey Proteins ◽  
Raw Milk ◽  
Hydrogen Phosphate ◽  
Sediment Formation ◽  
Bacterial Action ◽  
Sterilized Milk ◽  
Influence Of Ph

SummaryWhen the pH of milk was varied within the range 7·1 to 6·3 by addition of acid or alkali or through bacterial action, the reflectance of the milk after subsequent ultra-heat-treatment (UHT) was at a maximum of about pH 6·70. Below this value the reflectance dropped rapidly with decrease in pH. The cause of this decrease was the development of increasing amounts of sediment in the product. At pH 6·4–6·5, at least 90% of the casein and 40% of the whey proteins had been precipitated. The addition of 0·1% sodium di-hydrogen phosphate or 0·1% sodium citrate to the raw milk prevented the formation of the sediment. The role of calcium appeared important as small additions of calcium chloride or EDTA altered the patterns of sediment formation and reflectance with changing pH. Addition of 0·3% EDTA prevented sediment formation as the pH dropped.

188. The effect of commercial sterilization on the nutritive value of milk. V. The effect of commercial sterilization on the vitamin C of milk

1938 ◽  
Vol 9 (2) ◽  
pp. 185-187 ◽  
Author(s):  
K. M. Henry ◽  
S. K. Kon
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Chemical Method ◽  
Nutritive Value ◽  
Raw Milk ◽  
Sterilized Milk

1. Fifteen samples of raw and fifteen samples of commercially sterilized milk from the same bulk were analysed for vitamin C by the chemical method (titration with dichlorophenol-indophenol).2. The raw milk contained on an average 1·83 mg./100 ml. of total (reduced and reversibly oxidized) ascorbic acid. The corresponding figure for sterilized milk was 1·03 mg./100 ml., a loss of 43% of the original value.3. Storage of the sterilized milk for a period of 4·6 weeks resulted in a further reduction equivalent to about 30%.

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