Whole Milk Powder Research Articles

Incidence of Multiple Antibiotic Resistant Organisms Isolated from Retail Milk Products in Hermosillo, Mexico

Retail milk samples (231) of pasteurized, whole milk powder (WMP), and ultrapasteurized (UP) were collected in Hermosillo, Sonora, Mexico, to determine the incidence of multiple antibiotic resistance. Pathogens such as Escherichia coli, Staphylococcus aureus, and Salmonella were determined as well as nonpathogens such as Pseudomonas, Klebsiella, Serratia, and Hafnia alvei. Drug resistance of each isolated culture was tested using the Kirby-Bauer technique. The following antibiotic discs and concentrations were used: amikacin 30 mcg, ampicillin 10 mcg, carbenicillin 100 mcg, cefamandole 30 mcg, chloramphenicol 30 mcg, erythromycin 15 mcg, gentamicin 10 mcg, kanamycin 30 mcg, nitrofurantoin 300 mcg, penicillin 10 U, polymixin B 300 U, tetracycline 30 mcg, and tobramycin 10 mcg.Sixty-seven percent of the pasteurized milk samples contained fecal coliforms with multiple drug resistance. Four percent contained Salmonella which was 100% resistant to penicillin and showed some resistance to polymixin B and chloramphenicol. S. aureus which was drug resistant was present in 2.9% of the samples. The WMP and UP samples were relatively pathogenic free; however, nonenteric coliforms were detected showing multiple drug resistance. E. coli isolated in 1 UP showed resistance to ampicillin, chloramphenicol, gentamycin, polymixin B, and tetracycline.A high incidence of drug-resistant organisms in milk products represents a public health hazard in that food poisoning outbreaks would be difficult to treat and this pool of multidrug-resistant organisms in the food supply represents a reservoir for transferable resistant genes. An active surveillance and monitoring program should be mandated to minimize this risk for the consumer.

Storage of milk powders under adverse conditions. 2. Influence on the content of water-soluble vitamins.

Storage of milk powder under unfavourable conditions accelerates the normally slow deterioration in nutritional quality. The effects of such storage on the water-soluble vitamin composition were examined. (a) Spray-dried whole milk containing 25 g water/kg was stored at 60 degrees and 70 degrees and sampled weekly to 9 weeks. (b) Spray-dried whole milk and skimmed milk were adjusted to contain 40 and 100 g water/kg and stored at 37 degrees in nitrogen and in oxygen. Samples were taken for analysis at intervals during storage. The samples were analysed for eight B-complex vitamins and ascorbic acid, and also for total lysine, 'reactive lysine' and 'lysine as lactulosyl-lysine'. Storage at 60 degrees caused rapid destruction of folic acid (53% loss at 4 weeks) and slower loss of thiamin, vitamin B6 and pantothenic acid (18% at 8 weeks). There was no change in the content of riboflavin, biotin, nicotinic acid and vitamin B12. At 70 degrees the rate of destruction of the four labile vitamins was much increased; 18% or less survived at 4 weeks. At 37 degrees and 40 g water/kg there was little change in total and 'reactive' lysine during storage for 57 d. Lactulosyl-lysine was demonstrably present but at low concentration. There was considerable loss of folate (72%) and ascorbate (91%) during storage for 30 d in O2, but no significant loss in N2. Thiamin fell by approximately 12% in 57 d, equally in O2 and N2. The content of the remaining vitamins was unchanged. At 100 g water/kg there were progressive Maillard changes. During 27 d in N2 the colour changed from cream to pale brown, but in O2 there was no perceptible colour change. Total lysine fell by 20% in 27 d, and 'reactive lysine' by 30%. Folate was stable during 16 d in N2, but largely (94%) destroyed in O2. Ascorbic acid was also destroyed in N2 as in O2. Thiamin fell by 41% in 27 d, equally in O2 and N2. Vitamin B6 was more labile, especially in N2, falling by 71% in 16 d. With skimmed-milk powder containing 100 g water/kg, storage at 37 degrees in O2 and N2 gave much the same results as for the corresponding whole-milk powder. The presence of milk fat had no marked effect on the stability of the water-soluble vitamins. Destruction of vitamins was clearly linked to the progress of Maillard-type reactions and was strongly influenced by time and temperature of storage, moisture content and, in some instances, by the presence of O2.

Storage of milk powders under adverse conditions. I. Losses of lysine and of other essential amino acids as determined by chemical and microbiological methods.

Whole-milk powders containing 25 g water/kg were stored for up to 9 weeks in sealed aluminium containers at elevated temperatures. Lysine and other essential amino acids were measured by chemical and microbiological methods. Storage at 60 degrees resulted in the progressive formation of lactulosyl-lysine. After 9 weeks, 30% of the lysine groups were present in this form. The powders still retained their natural colour and the levels of tryptophan, methionine, cyst(e)ine and leucine remained unchanged. Storage at 70 degrees resulted in the formation of lactulosyl-lysine followed by its complete degradation with the development of browning. Available tryptophan, methione, leucine and isoleucine decreased progressively during storage. The different methods for lysine determination gave widely dissimilar results. The direct fluorodinitrobenzene (FDNB) technique and reactive lysine from furosine were considered to be the most reliable methods. The FDNB-difference, dye-binding lysine, Tetrahymena and Pediococcus methods all seriously underestimated reactive or available lysine in heat-damaged milk powders. Tetrahymena and Pediococcus appeared to utilize lactulosyl-lysine as a source of lysine. The results are discussed in relation to storage and distribution of milk powders in hot climates.

A comparison of feeding reconstituted and dried milk upon the growth and carcass composition of calves.

1. The live-weight gain, carcass weight, edible carcass composition, efficiency of food conversion, and roughage intake were measured in three groups of calves fed for 87 d. After a 3-week feeding period on a common regimen, one group of calves was weaned on to a diet of dry whole-milk powder and chopped lucerne, the second group received a similar diet except that the whole-milk powder was reconstituted to a liquid milk, containing 12–15% dry matter. The third group was given the diet in the same manner as the second group except that the chopped lucerne was available ad lib.2. The mean live-weight gains for the three groups were 37.7, 47.6 and 52.7 kg respectively, the differences between the dry-fed and the liquid-fed groups being highly significant.3. Energy and nitrogen accretion in the edible carcass and efficiency of food conversion were superior in the second and third groups.4. The third group ate larger quantities of roughage, though the difference did not reach significance.5. The reasons for the superiority of the liquid milk diet are discussed in relation to the avoidance of ruminal fermentation of the milk.

Artificial rearing of pigs

1. Baby pigs were removed from the sow 36–48 h after birth and reared on a diet of reconstituted whole-milk powder until 28 d of age. The whole milk was either mildly or severely heated before spray-drying; the severe heating completely denatured the whey proteins.2. When the two milks were given at a high level of intake, either at hourly intervals or twice daily, severe scouring and some deaths occurred, the incidence being higher among pigs receiving the severely heated milk. The severe heat treatment also reduced the nutritive value of the milk powder as measured by the performance of the pigs during the 1st week of life. However, no difference in the nutritive value of the two milks was apparent for the surviving pigs over the whole experimental period.3. There were no deaths when the two milks were given at a moderate level of intake and at hourly intervals. The effect of heat treatment on performance was similar to that at the high level of intake.4. The apparent digestibility of the nitrogen in the diet was similar for both milks. However, balance trials could not be carried out when scouring occurred, when differences between the milks were most likely to be apparent. The N retention was similar with both milks at 7 d of age, although retention was higher when the severely heated milk was given to pigs between 14 and 21 d of age.5. The digestion of the two milks was studied in 28-d-old pigs. The ability of the severely heated milk to clot in the stomach was greatly reduced compared with that of the mildly heated milk, but the performance of the pigs was unaffected. No other differences in the digestion of the milks were found. The ability of the diet to clot in the stomach appeared to be unimportant at this age.6. It is possible that a reduction in the clotting ability of the severely heated milk was responsible for the decreased efficiency of digestion during the 1st week of life.

Nutrition of the milk-fed calf

Abstract An intake of spray-dried whole-milk powder equivalent to 2% of body weight was maintained in calves during the first 12 weeks of life when the powder was supplemented with iron, copper, and magnesium. Intakes relative to body weight declined after the age of 12 weeks when fortification with iron and copper ceased. Gradual increases in the dry-matter content of milk to compensate for the decline in abomasal capacity relative to body weight did not enhance intake between the age of 12 and 16 weeks. Supplementation of spray-dried whole-milk powder with iron and copper at levels of 46.7 and 5.1 mg/kg respectively maintained blood haemoglobin concentrations. Fortification of the powder with 0.25 g of magnesium per kg did not prevent, but appeared to delay, the onset of progressive hypomagnesaemia. An increase in the apparent digestibility of fat and a decrease in the digestibility of lactose and ash were noted with advancing age. Reconstitution rate did not affect the digestibility of milk nutrients up to the age of 16 weeks.

Carcass quality of white veal from friesian bull calves

Abstract The carcass composition of 38 Friesian bull calves fed exclusively on reconstituted spray-dried whole-milk powder supplemented with iron, copper, and magnesium, and averaging 90 kg in hot carcass weight, was studied. The calves came from five nutritional treatments. There were no differences between treatments in carcass weight or composition. The carcasses averaged 61.3% salable meat, 26.4% bone, 11.6% fat trim and waste, and 0.7% kidneys.

Serological differentiation of cow's, buffalo's, goat's and sheep's milks

SummaryMilks of the closely related species ox, buffalo, goat and sheep were differentiated by the precipitin test using antisera to blood serum proteins. The antisera were made specific for the homologous species by absorption. The component of milk tested was the lactalbumin–lactoglobulin fraction present in whey. Fraudulent sale of diluted buffalo's milk, cow's milk–buffalo's milk–water mixtures and reconstituted whole and skim-milk powders as genuine cow's milk was detected. Of 270 milks serologically tested, 233 were cow, 26 buffalo, 1 goat, 3 cow–buffalo mixtures, 2 reconstituted whole-milk powders and 5 reconstituted skim-milk powders. Of the samples serologically identified as cow, 135 had analytical figures for fat and solid-not-fat (SNF) only just outside or within the buffalo range.Milk from any one species was detected in a concentration of 5% (v/v) in milk of a related species. Species identification was made of human milk stains in 2 medicolegal cases. Fresh cow's milk, reconstituted whole-milk powder and reconstituted skim-milk powder were differentiated.

牛乳および乳製品の無機塩類に関する研究

牛乳および乳製品の無機塩類に関する研究の第一段階として,発光分光分析によつて,K, Na, Ca, Mg,P, Si, Zn, Sn, Cu, Mo, Mn, B, P, Al等の常成分元素を確認し,その定量を行ない,まずKおよびNaについて報告した.試料として粉乳22,市乳106,合乳83,および個体乳71点を1957～1960年に採取し,地域,季節,個体および泌乳時期による変化を検討した.採取は毎月1回とし,試料は550～600°Cで灰化し,炎光分光分析によつて定量した.その結果,灰分1g中のKおよびNa量は,生乳ではそれぞれ216.75および75.50mgであつたが,市乳ではこれより抵く,201.33および72.03mgであつた.このこと特にKの減少は,原乳とその処理乳とを直接比較することによつて明らかであるが,その理由については検討中である.牛乳中のKは,冬から春にかけて低くなり,夏と秋は高い.これは,この時期に末期乳が多くなるためである.5頭の乳牛の総計8泌乳期について調べたところ,泌乳停止の前月から,急激にKが減少することが認められた.Naは逆に,泌乳末期に向かつて増加するが,その変化は緩徐であるため,季節的差異も,Kほどには認められない.また牛乳中のKとNa量は,5%レベルで負の相関を示した.すなわち,KとNa量の高低は,相反する傾向がある.地域および個体による差は,Naではきわめて大きいが,Kでば小さくて,その量は比較的一定している.

Dental Caries and Growth in Rats Fed Whole-Milk Powders with Increasing Lysine Deterioration

Dental Caries and Growth in Rats Fed Whole-Milk Powders with Increasing Lysine Deterioration

405. The composition of the soluble and insoluble portions of reconstituted milk powders

1. The mode of distribution of the constituents of centrifuged reconstituted whole-milk powder manufactured by different processes has been determined at 20 and 50° C.2. Where considerable ‘insolubility’ exists, protein is carried into the fat layer and fat into the sediment layer in quantities directly related to the degree of ‘insolubility’. The fat in the sediment of roller powders appears to be associated almost entirely with the protein which remains insoluble at 50° C.3. The sediments from reconstituted whole- and separated-milk powders made by different manufacturing processes have been obtained in bulk by vigorous centrifuging (14,500 ×g). Analysis of these sediments reveals considerable similarity between them, and it is concluded that a well-washed sediment would consist mainly of denatured calcium caseinate together with calcium and phosphorus in the same proportions as in normal tricalcium phosphate, Ca3(PO4)2, the calcium caseinate and most of the calcium phosphate probably being in the form of a casein-phosphate complex.4. The accuracy of some published methods of measuring milk powder solubility has been considered, and the inaccuracies arising from the non-homogeneity of the fat and sediment layers are stressed.

Liver Damage and Growth in the Rabbit

A diet of whole-milk powder (fortified with manganese, copper, iron, and iodine) is inadequate for the rabbit in at least two respects. Growth is subnormal and the livers are fatty and cirrhotic. Large amounts (50%) of dehydrated alfalfa meal are needed to prevent liver injury, while only small amounts (1%) are needed to stimulate the growth rate. Experiments involving 23 diets and 177 animals indicate that milk does not contain a toxic factor responsible for these results, and that the results are not due to the lack of roughage or of any of the known fat- and water-soluble vitamins or of the labile methyl groups. Preliminary attempts to extract the growth-promoting factor from alfalfa with water were unsuccessful. Purified diets when supplemented with a complete vitamin mixture offered no protection against liver damage, but when supplemented with yeast offered partial protection. In these diets crude casein produced better growth than purified casein, indicating the need of the rabbit for a third factor, possibly similar to the “animal-protein factor” of Cary et al. ('46) and Coombs ('47).

358. The effect of a high pre-heating temperature with and without ethyl gallate on the storage life of whole-milk powder spray-dried on a Gray-Jensen drier

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.

338. The ferric thiocyanate method of estimating peroxide in the fat of butter, milk and dried milk

The ferric thiocyanate method of estimating peroxide in fats has been modified to give greater sensitivity and greater stability of the reagent. As the 96% acetone used by Chapman & McFarlane (3)and Lips et al.(4) only dissolves about 0.5% butterfat, the sensitivity of the test was increased by using, as solvent, the mixture of benzene and methanol used by Bolland et al. (6) in the determination of rubber peroxides, which dissolves at least 10% butterfat. Instead of using a prepared reagent which gradually deteriorates, the ferrous salt and thiocyanate are added in aqueous solution during the test, and, moreover, ferrous salts appear to be more stable in this solvent than in acetone. The modified method is sufficiently sensitive to measure the peroxide value of the fat of freshly drawn milk and has been applied to the study of the first stages of oxidation in milk, butter and whole-milk powder.

326. The effect of temperature of pre-heating, of clarification and of bacteriological quality of the raw milk on the keeping properties of whole-milk powder dried by the Kestner Spray Process

(1) Increasing the pre-heating temperature of the milk from 165 to 190° F. before spray-drying greatly improved the resistance of the powder to the development of tallowy ‘off’-flavours on storage. From the results of accelerated tests at 47 and 37° C. a storage life (in air) of the order of 2 years could safely be predicted for the powders from milk pre-heated at the higher temperature. Confirmation has now been obtained by storage of the powders for 2½ years at 15° C. and at room temperature.(2) Improvement in the bacteriological quality of the milk supply, and more careful control during its passage through the plant, produced some improvement in the keeping properties of powders prepared from milk pre-heated at the lower temperature, but had relatively little effect on the keeping properties of the powder when the higher preheating temperature was used.(3) The shapes of the deterioration curves for the various powders showed that the effect of the higher pre-heating temperature and of improvement in the milk supply was to extend the induction period which precedes rapid deterioration. The protective effect of both factors was greater when measured at the ‘slightly tallowy’ or ‘fairly good’ stage than when comparison was made at a more advanced stage of decomposition.

328. Experiments on the use of antioxidants in spray-dried whole-milk powder

1. Of a number of substances tested for antioxidant activity in laboratory-made spray-dried milk powder, ascorbic acid and ethyl gallate proved most promising. Both of these substances materially increased the resistance of the powder to the development of tallowiness without producing any foreign flavour in the milk.2. The actitivy of both substances has been confirmed in factory-made spray-dried powder, ethyl gallate being much the more powerful of the two. Ethyl gallate at a concentration of 0·07% increased the storage life of powder in the accelerated tests 2½–3-fold.3. Ethyl gallate remained unchanged during storage of the powder, but the concentration of ascorbic acid decreased, rapidly at first and then more slowly.

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

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.

The Influence of Insufficient Diets Upon Tumor Recurrence and Growth in Rats and Mice

Several investigators have already reported the effects of especially limited diets upon the growth of neoplasms. In such studies diets have been employed which were deficient in some specific vitamin or in fat, protein, or carbohydrate. In the present paper we wish to report the effect of diets which were adequate in every respect except quantity, upon spontaneous and transplantable cancer. In the present experiments our animals were given a food mixture containing every requirement, but the quantity fed was greatly restricted. EXPERIMENTAL Transplanted Tumors. —In the transplantation experiments we used the Flexner-Jobling rat carcinoma. The method of inoculation and of recording the progress of the transplanted tumors was identical with the technic fully described by us in a previous article (1). The basic diet consisted of a uniform mixture of 32.1 parts by weight of cracker meal (National Biscuit Co.) and 7.7 parts by weight of whole milk powder (Klim, Merrell-Soule Co.). A dough was prepared with 50 parts of the basic diet and an equal amount of water, and a weighed amount of the food was given daily to each animal. This diet has been shown repeatedly to be adequate for the growth, maintenance, reproduction, and perfect milk production of the rats and mice (2, 3). Throughout the present experiments the rats were maintained upon the designated ration from seven to fourteen days previous to tumor inoculation.

Antiscorbutic Potency of Whole-Milk Powder.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAntiscorbutic Potency of Whole-Milk Powder.G. W. Cavanaugh, R. A. Dutcher, and J. S. HallCite this: Ind. Eng. Chem. 1924, 16, 10, 1070–1073Publication Date (Print):October 1, 1924Publication History Published online1 May 2002Published inissue 1 October 1924https://doi.org/10.1021/ie50178a030RIGHTS & PERMISSIONSArticle Views17Altmetric-Citations4LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (626 KB) Get e-Alerts