Utilization of a low-lactose milk

This study was undertaken to determine if a milk containing prehydrolyzed lactose, yet affording full nutritional benefits, could be ingested by a milk intolerant (MI) population without the symptoms of lactose intolerance. MI was defined by the failure of serum glucose to rise greater than 20 mg/100 ml after ingestion of 50 gm of lactose as well as by subjective and objective symptoms and signs after consumption of both 12.5 gm of lactose in water and 250 ml of skim milk. Lactose tolerance (LT) was evidenced by both lack of symptoms and a concomitant rise in serum glucose of greater than 20 mg/100 ml after ingestion of 50 gm lactose in water. A series of four, two hr tolerance tests were given to 12 MI patients and 12 LT controls. The following solutions were employed: 12.5 gm lactose, 250 ml skim milk. 250 ml low-lactose skim milk, and 6 gm glucose plus 6 gm galactose. In the MI group, significant differences were apparent between the tolerance test utilizing skim milk and that using low-lactose skim milk; no such differences were observed in the LT group. These observations indicate that in the MI population the lactose in skim milk was poorly absorbed or tolerated, but after hydrolysis the low-lactose skim milk was well tolerated. A MI individual then, appears able to absorb the monosaccharides of the prehydrolyzed milk and can, furthermore, tolerate the low-lactose skim milk without suffering from symptoms normally associated with lactose intolerance.     

Ureteral obstruction secondary to inflammatory iliac aneurysm]

BACKGROUND: The aim of the current study was to evaluate the prevalence of lactose malabsorption (LM) in Galicia (NW Spain) in order to design nutritional intervention and/or public education strategies for high risk groups. METHODS: We conducted a study of LM by breath-hydrogen carbohydrate absorption test (BH2 test) in 850 healthy subjects. All subjects underwent BH2 tests following ingestion of a aqueous solution of 2 g lactose/kg body weight up to a maximum of 50 g. Subjects with LM were retested after ingesting 250 ml of milk and/or 250 ml of yogurt. RESULTS: The frequency of LM in the subjects who ingested 2 g lactose/kg body weight was 32.5%. This percentage decreased significantly with a decrease in the quantity of administered lactose and the vehicle was milk or yogurt-only 13.7% was LM after 250 ml of milk and 3.8% after 250 ml of yogurt. Gastrointestinal symptoms also depend on dosage of lactose and vehicle, decreasing from 54.3% after 2 g lactose/kg to 18.5% after milk and to 0% after yogurt. The frequency and number of gastrointestinal symptoms were significantly higher (p < 0.001) in LM than in lactose absorption (LA). CONCLUSIONS: Lactose malabsorption is prevalent in the population of Galicia. An important number of subjects identified as LM with usual clinical testing become LA when the ingestion of dairy products is limited so that the amount of lactose consumed is similar to that contained in a usual serving. Our results suggest the importance of BH2 testing following ingestion of usual consumed amounts of lactose per serving.     

Effect of milks inoculated with Lactobacillus acidophilus or a yogurt starter culture in lactose-maldigesting children

Dairy products containing live bacteria that possess lactase activity are used for dietary management of lactose maldigestion. The efficacy of acidophilus milk and the effect of consuming unfermented milk that had been inoculated with yogurt bacteria have not been examined in children. We compared scores for breath H2 excretion and symptoms of 20 lactose-maldigesting children following ingestion of 250 ml of uninoculated milk with two identical milks inoculated with 10(10) cells of Lactobacillus acidophilus or with a commercial yogurt starter culture containing 10(8) cells of Lactobacillus lactis and 10(10) cells of Streptococcus thermophilus. Nine of 10 subjects who were symptomatic following ingestion of uninoculated milk experienced a reduction in symptoms following ingestion of milk inoculated with L. acidophilus, without a decline in H2 excretion. Five of 6 subjects who were symptomatic following uninoculated milk had decreased symptoms and a significant reduction in H2 excretion following milk inoculated with the yogurt culture. For lactose-maldigesting children, milks inoculated with L. acidophilus or with a yogurt culture were associated with decreased symptoms compared with those with uninoculated milk.     

Tolerance to the daily ingestion of two cups of milk by individuals claiming lactose intolerance

We reported previously that consumption of one cup of milk (240 mL) per day produced negligible symptoms in lactase-nonpersistent (LNP) individuals self-described as being severely lactose intolerant. We hypothesized that such LNP individuals could also tolerate two cups of milk per day if taken in two widely divided doses with food, and that psychologic factors play a role in perceptions of lactose intolerance. The Minnesota Multiphasic Personality Inventory 2 (MMPI-2) was administered to 19 LNP subjects self-described as markedly lactose intolerant (S-LNP), 13 LNP subjects who denied lactose intolerance (A-LNP), and 10 lactase-persistent individuals who believed they were lactose intolerant (S-LP). Symptoms were recorded when LNP subjects ingested 240 mL regular or lactose-hydrolyzed milk twice daily for 7 d in a double-blind crossover study. The results showed that neither LNP group had a significant increase in symptoms (P < 0.05) during the regular compared with the lactose-hydrolyzed milk periods. However, S-LNP subjects reported significantly greater gaseous symptoms than did the A-LNP subjects during both treatment periods. The MMPI-2 showed a high score on the "lie" validity scale for S-LNP subjects. We conclude that LNP subjects tolerate two cups of milk per day without appreciable symptoms. S-LNP subjects have underlying flatulence that is misattributed to lactose intolerance. MMPI-2 results were of questionable validity because of the high rate of dissimulation by LNP subjects.     

Significance of human cytomegalovirus DNA detection in immunocompromised heart transplant patients

Fifteen lactose malabsorbers were studied to evaluate the effects of consumption of milk containing different strains of Bifidobacterium longum on lactose digestion. Influences of different growth substrates, bile sensitivity, and lactose transport on lactose digestion by bifidobacteria were also investigated. Lactose malabsorption was determined by measuring breath hydrogen excretion of subjects fed four different test milks (three of which contained 5 x 10(8) cfu/ml of B. longum) on 4 different d using a randomized, double-blinded trial. Test milks included 1) 400 ml of lowfat milk (control), 2) 400 ml of milk containing B. longum B6 that had been grown with lactose, 3) 400 ml of milk containing B. longum B6 grown with lactose plus glucose, or 4) 400 ml of milk containing B. longum ATCC 15708 grown with lactose. beta-Galactosidase activity was highest in milk containing B6 grown with lactose but was extremely low in milk containing B6 grown with lactose and glucose. Consumption of milk containing B6 grown with lactose resulted in significantly less hydrogen production and flatulence than occurring after consumption of control milk or the milk containing B6 grown with both lactose and glucose. Hydrogen production after ingestion of 15708 was also significantly lower than hydrogen production after ingestion of the control milk. We concluded that milks containing B. longum might reduce breath hydrogen response and symptoms from lactose malabsorption when the culture is grown in a medium containing only lactose to induce a higher beta-galactosidase level and increase rate of lactose uptake.     

Raising milk energy content retards gastric emptying of lactose in lactose-intolerant humans with little effect on lactose digestion

Lactose digestion improves when the energy content of a meal is raised, perhaps due to delayed gastric emptying; however, this has not been demonstrated directly. It is not known whether lactose-intolerant subjects should consume full-fat or high energy milk instead of half-skimmed milk. In this study, breath 13CO2 and hydrogen (H2) measurements were combined to assess simultaneously the effect of increasing milk energy content on gastric emptying, digestion, and tolerance of lactose. On two separate days, 11 adult lactose maldigesters ingested, in the fasting state, a single dose of 710 kJ half-skimmed milk or 1970 kJ high energy milk. Both contained 18 g lactose and were supplemented with 100 mg 13C-glycine for breath 13CO2 measurement. For 6 h after milk ingestion, samples of expired breath were collected, and subjects scored their symptoms on a four-grade questionnaire. Gastric emptying was measured from excretion of breath 13CO2. The mean gastric emptying half-time was significantly longer after ingestion of high energy milk than after half-skimmed milk (84 +/- 4 vs. 64 +/- 4 min, P = 0.004). The mean area under the breath H2 excretion curve measured for 6 h was 330 +/- 61 microL/L after subjects consumed high energy milk vs. 470 +/- 82 microL/L after they consumed half-skimmed milk (P = 0.07). Mean symptom scores did not differ after ingestion of the two milks, but only two subjects experienced disturbing symptoms after high energy milk ingestion compared with five subjects after ingestion of half-skimmed milk (P = 0.56). Although ingestion of high energy milk delayed the gastric emptying of lactose for significantly longer than the ingestion of half-skimmed milk (P < 0.01), it did not lead to significant improvement in symptoms and reflected only a trend toward improved lactose digestion (P = 0.07), as measured by the area under the breath H2 excretion curve. These results indicate that it is not beneficial for most lactose-intolerant subjects to replace consumption of half-skimmed milk by milk with a higher energy content.     

Factors that influence milk cholesterol and lipid phosphorus: content and distribution

Average cholesterol content of 356 raw milk samples was 152.2 mug/ml and upon centrifugation (3000 X g for 8 min), 16.9% was distributed in the skim milk phase. Lipid phosphorus averaged 19.0 mug/ml and was partitioned 50:50 between cream and skim milk phases. Weight ratios of cholesterol to lipid phosphorus for milk and skim milk were 8.30:1 and 2.94:1. When variation due to milk yield, fat percent, and somatic cell numbers (deoxyribonucleic acid percent reflectance) was accounted for by least squares, cholesterol content and distribution did not differ among breeds (Holstein, Jersey, and Guernsey). Breed differences in lipid phosphorus content of whole milk could not be detected. However, Holsteins had a significantly lower content of lipid phosphorus and a higher weight ratio for skim milk. Milk yield, fat content, and somatic cells affected responses of cholesterol and lipid phosphorus. This supports a multiple origin concept for membrane material in skim milk.     

Adenosine triphosphate in milk

Freshly secreted goat's milk contains a number of viable metabolic pathways including those for the synthesis of triglycerides and phospholipids. Toward understanding this matter, amounts of the fundamentally important energy substrate, adenosine triphosphate, in goat's milk were evaluated. Milk left in the goat udder overnight had less adenosine triphosphate (12.4 muM) than fresh secreted milk (37.6 muM). In similar experiments the skim milk derived from whole accumulating in the udder overnight was lower in adenosine triphosphate (14.2 muM) than skim milk from freshly secreted milk (26.0 muM). To determine changes in quantities of adenosine triphosphate after milking, milks were divided into two parts, one containing only milk and the other milk plus 2,4-dinitrophenol and sodium arsenate, inhibitors of oxidative and substrate level phosphorylation. Adenosine triphosphate in milk decreased during 4-h in vitro incubations, and the rate of decline was markedly greater in the presence of the inhibitors. Thus, freshly secreted goat's milk contains significant amounts of adenosine triphosphate, and more can be synthesized therein after removal from the udder. In limited samples human and bovine milks contained much lower concentrations of the compound than those in goat's milk.     

Lactose maldigestion is not an impediment to the intake of 1500 mg calcium daily as dairy products

BACKGROUND: A National Institutes of Health consensus conference concluded that a daily calcium intake of 1500 mg reduces the severity of osteoporosis. Because dairy products are the main natural source of dietary calcium, a diet providing 1500 mg Ca must contain large quantities of dairy products. However, it is widely believed that the lactose content of these products will not be tolerated by persons with lactose maldigestion (approximately 30% of the adult US population). OBJECTIVE: We evaluated the symptoms of lactose maldigestion and digestion when the diet was supplemented with dairy products providing 1300 mg Ca/d. DESIGN: Sixty-two women (31 with lactose maldigestion and 31 without) were studied in a double-blind, randomized protocol. Symptoms were compared during 1-wk periods when the diet was supplemented with 480 mL (2 cups) milk, 56 g cheese, and 240 mL yogurt provided as conventional products (34 g lactose/d) or as lactose-hydrolyzed products (2 g lactose/d). RESULTS: Women who digested lactose reported no significant difference in symptoms between the 2 treatment periods. Women with lactose maldigestion reported significantly increased flatus frequency and subjective impression of rectal gas during the period of high lactose intake; however, bloating, abdominal pain, diarrhea, and the global perception of overall symptom severity were not significantly different between the 2 treatment periods. CONCLUSION: The symptoms resulting from lactose maldigestion are not a major impediment to the ingestion of a dairy-rich diet supplying approximately 1500 mg Ca/d.     

Use of enzyme substitutes in hypolactasia

The paper presents the results of clinical and laboratory studies of lactrase, a drug containing lactase. This agent is recommended for splitting lactic sugar in subjects with appreciably decreased production of endogenous lactase (hypolactasia). Twenty-eight patients with this condition were examined. Manifest clinical symptoms of the condition were observed after loading with 50 g of lactose in all examinees. Addition of 250 mg of lactrase to lactose led to complete clinical compensation of the deficit of endogenous lactase in 75% examinees, and if 500 mg of lactrase was administered, hypolactasia was compensated in virtually all patients. A single intake of 50 g of lactose with lactrase causes a statistically reliable increase of glycemia in such patients. Moreover, a reliable effect of lactrase was observed when measuring galactose in the urine following the lactose test with 250 and 500 mg of lactrase. Our results indicate a high efficacy of lactrase in the treatment of patients with hypolactasia.     

Disturbed galactose metabolism in elderly and diabetic humans is associated with cataract formation

Lactose consumption has been associated with a high incidence of cataract in northern Indian and southern Italian populations. Galactose absorbed after hydrolysis of lactose from milk in individuals with normal lactase activity is considered responsible. However, lactase-deficient subjects who often avoid drinking milk are able to digest lactose and absorb free galactose in fermented milk and yogurt. This study was conducted to evaluate the relationships between milk and yogurt consumption, galactose metabolism and cataract risk. Milk ingestion was dose-related with cataract risk in lactose digesters (particularly in diabetics) but not in lactose maldigesters. Conversely, yogurt intake had a protective dose-effect on cataract formation for the whole population. Maximal galactose concentrations after an oral galactose test increased exponentially with age. Red blood cell galactokinase activity was significantly lower in elderly subjects (> 60 y) than in young individuals (P < 0.05), and galactose-1-phosphate uridyl-transferase activity was significantly lower in institutionalized subjects and in home-living elderly with cataract than in healthy elderly subjects (P < 0.05). We conclude that the cataractogenic action of milk lactose is dependent on the disturbance of galactose metabolism in elderly subjects and that yogurt is not cataractogenic, although the mechanism of the protective effect of yogurt remains unknown.     

The outbreak of an epidemic of tick-borne encephalitis in Kielec province induced by milk ingestion

New liquid UHT milks supplemented with iron (0.9-1.4 mg/100 ml), vitamin C (1-7 mg/100 ml), lactose (2-4 g/100 ml) and linoleic acid (200-400 mg/100 ml), named growth milks, have recently become available to satisfy the specific nutritional needs of children aged 1-3 years. But the iron-vitamin C mixture could activate the lactose-induced Maillard reaction and tryptophan (Trp) oxidation in proteins. We have therefore examined the Amadori product and Trp concentrations of these milks. Forty-two commercial growth milks from five firms were analysed for the Maillard reaction and the soluble protein Trp content and compared with 64 UHT milks. The furosine concentration of total proteins was two to four times higher in 'growth' milks than in standard UHT milks, indicating a proportional loss of available lysine. The Trp fluorescence of undenatured proteins soluble at pH 4.6 was almost three times lower in 'growth' than in standard milks and Trp concentration 36% lower suggesting destruction of this oxidation-sensitive amino-acid. The mechanism of Trp destruction remains to be elucidated, and the roles of iron and Amadori products determined.     

Estimation of the bioavailability of zinc and calcium from human, cow's, goat, and sheep milk by an in vitro method

The availability of zinc and calcium from human, cow's, goat, and sheep milk is evaluated by an in vitro method that involves a simulated human gastrointestinal digestion followed by measurement of dialyzability of zinc and calcium. Zinc availability of milk showed the highest value for human milk (15.0%) and the lowest for sheep milk (1.0%), in both whole and skim milk. Calcium availability of the different types of milk did not differ significantly and ranged between 18 and 23%. No significant differences in availability between whole and skim milk were found for both elements, except for zinc in cow's milk.     

Induction of SLPI (ALP/HUSI-I) in epidermal keratinocytes

The hypothesis that consumption of bifidobacteria by humans would increase colonic bifidobacteria and decrease breath hydrogen excretion was examined. A commercially available strain of bifidobacteria was tracked through the gastrointestinal tract. We determined that a 12-d feeding period of 10(10) cells of exogenous bifidobacteria daily was adequate to achieve a stable number of exogenous bifidobacteria in the colon. A 12-d washout period was chosen because the exogenous bifidobacteria could no longer be detected at that time. A double-blind crossover study used both male and female subjects. The order of treatment with skim milk alone or skim milk + bifidobacteria was randomized. Breath hydrogen excretion (micromol/L) and fecal counts of total bifidobacteria [log colony forming units (CFU)/g feces] were not significantly different between males and females and were not affected by consumption of exogenous bifidobacteria. Calculations based on the numbers of exogenous bifidobacteria consumed and the fecal numbers of exogenous bifidobacteria excreted suggested that numbers of the exogenous strain increased within the gastrointestinal tract. These data suggest that it is difficult to permanently alter total colonic bifidobacteria and affect physiologic function (net hydrogen in the colon as reflected by breath hydrogen) by feeding bifidobacteria, although the percentage of the total bifidobacteria represented by the exogenous strain can be affected.     

A longitudinal study of the protein, nitrogen, and lactose contents of human milk from Swedish well-nourished mothers

The contents of total nitrogen, nonprotein nitrogen, lactose, and individual milk proteins have been determined in human milk from well-nourished Swedish mothers. Breast milk samples from 50 mothers at different stages of lactation (up to 170 days) were collected. Furthermore, three mothers gave samples repeatedly throughout the whole lactation period. The protein content in mature milk was found to be 0.8 to 0.9% by amino acid analysis. The nitrogen content and the contents of the major human milk whey proteins, alpha-lactalbumin and lactoferrin, are very high for the first few days, then decrease rapidly and reach, thereafter, the more slowly declining level of mature milk. Nonprotein nitrogen and the nonspecific milk protein serum albumin are present in constant concentrations throughout lactation. The daily milk volumes were determined and found to be 500 to 600 ml in the very early part and 700 to 800 ml in the later part of the lactation period.     

Lactose in human nutrition

The disaccharide lactose is naturally present as a component of foods in milk and dairy products. In the gastrointestinal tract, lactose is hydrolysed by the enzyme beta-galactosidase (lactase) into glucose and galactose. These components are absorbed. In most people lactase activity decreases at the age of approximately 2 years of age. After this lactose intake can cause symptoms of bloating, flatulence, abdominal pain and diarrhoea due to the lactose reaching the large intestine. This phenomenon is called lactose intolerance. It is generally recommended that these people abandon the consumption of milk and dairy products. However, most lactose-intolerant people are able to digest small amounts of milk (approximately 200 ml). They can also consume cheese without (hard and semi-hard cheese) or only low lactose content (only present in 10% of soft cheese). These products are a very important source of calcium.     

Mechanisms of secretion: effects of colchicine and vincristine on composition and flow of milk in the goat

Colchicine, the plant alkaloid, produced a dramatic decrease in milk flow when infused into the udder of the goat. The compound (1 to 5 mg) dissolved in 5 ml of water was inserted into one side of the under via the teat canal. Such treatments consistently caused a depression in milk yield from the infused side with maximum at 36 h and substantial reversal by 72 to 96 h. Milks from both the infused and uninfused sides of the udder were essentially normal in composition (fat, protein, and lactose). However, globulins and riboflavin were elevated in milks from the infused side. The plant alkaloid, vincristine, produced effects on milk secretion similar to those of colchicine but at dosages roughly one-tenth the latter. The two substances had no effect on the amount of milk from the uninfused side of the udder. Experiments employing [carbon-14] colchicine revealed that less than 20% of the infused colchicine is secreted in the milk. Both the secretion of fat globules and the emptying of secretory vesicles by the lactating cell are inhibited by colchicine indicating that a portion of the cell population is turned off from secretion. Plant substances such as colchicine and vincristine may at times limit yields of milk, especially in grazing ruminants.     

Routine analysis of proteins by Kjeldahl and Dumas methods: review and interlaboratory study using dairy products

The Kjeldahl and Dumas (combustion) methods were compared in 11 laboratories analyzing samples of milk, skim milk powder, whole milk powder, whey protein concentrate, infant formula, casein, caseinate, 2 reference compounds (glycine and EDTA), and a secondary reference skim milk powder. The comparison was conducted by using international standards where applicable. Overall means were 8.818 g N/100 g by the Kjeldahl method and 8.810 g N/100 g by the Dumas method. No evidence was found for a consistent bias between methods that may be of concern in the trading of dairy produce. A review of more than 10 related trials revealed a lack of consensus in the bias between the 2 methods, suggesting that differences in methodology and sources of systematic error may be contributors. For samples containing > 2 g N/100 g, the Dumas relative repeatability and reproducibility standard deviations were consistently about 0.35 and 0.75%, respectively, whereas the corresponding Kjeldahl values declined generally with N content and were significantly larger. The Dumas precision characteristics may be due to the dominance of Leco analyzers in this trials, and in most other recent trials, rather than an inherent method attribute. Protein determination methods for dairy products need to be reviewed and updated. The Dumas method needs Codex Alimentarius status as a recognized test method.     

Intestinal barrier function and cow's milk sensitization in guinea pigs fed milk or fermented milk

BACKGROUND: The respective effect of milk and fermented milks on intestinal barrier capacity and on sensitization to beta-lactoglobulin was studied using a guinea pig model of cow's milk allergy. METHODS: Guinea pigs were fed a control diet or the same diet supplemented with milk, fermented milk (Streptococcus thermophilus and Bifidobacterium breve), or dehydrated fermented milk. Intestinal barrier capacity to macromolecules was assessed in an Ussing chamber, and sensitization to cow's milk proteins was measured by systemic anti-beta-lactoglobulin immunoglobulin G1 titers and by intestinal anaphylaxis, the latter assessed by the beta-lactoglobulin-induced increase in short-circuit current of jejunal fragments (deltaIsc(beta-LG)). RESULTS: The electrical resistance of jejunum was similar in the four groups (approximately 80 omega/cm2) suggesting the same paracellular permeability. The transport of 14C-beta-lactoglobulin from mucosa to serosa was significantly decreased in the animals fed dehydrated fermented milk (403+/-131 ng / hr x cm2) compared with that in control animals or animals fed milk (767+/-250 ng / hr x cm2 and 749+/-475 ng / hr x cm2, respectively; p < 0.05). Milk fermentation did not modify native beta-lactoglobulin concentration but anti-beta-lactoglobulin immunoglobulin G1 titers were higher in fermented milk and dehydrated fermented milk (log10 titer = 2.86 and 2.79, respectively) than in guinea pigs fed milk (log10 titer = 2.5; p < 0.007). However, beta-lactoglobulin-induced intestinal anaphylaxis remained the same in the three groups (deltaIsc(beta-LG), 9.6+/-4.1 microA/cm2, 8.5+/-4.3 microA/cm2, and 8.5+/-3.4 microA/cm2 in milk-fed, fermented milk-fed, and dehydrated fermented milk-fed guinea pigs, respectively). CONCLUSIONS: The intestinal barrier capacity to milk proteins seems to be reinforced by dehydrated fermented milk, but milk and fermented milks are equally efficient in inducing cow's milk allergy in guinea pigs.     

Calcium absorption by the rat from various milks in relation to their total phosphorus and lactose contents

The absorption of calcium corresponds to a strictly determined mechanism inhibited by phosphates and activited by carbohydrates. We investigate in what extent the absorption of milk calcium from various species has the same proceeding. 4 months old rats are given orally solutions of CaCl2 alone or in combination with sodium dihydrogen phosphate or lactose or these both compounds. We compare calcium absorption of these solutions to that of milk from woman, cow or sow, or to dilutions of these two latter milks. All these fluids are dosed so that they correspond each other by their respective content in total calcium, total phosphorus and lactose. Each solution contains 45Ca. Blood samples 1,30, 4, 6 and 24 hours after ingestion allow establishing the variations of plasma radioactivity. Rats are sacrified after 24 hours. In certain cases, samples from digestive tube contents and feces provide a coefficient of calcium absorption. The osseous retention is obtained from femur radioactivity. In breif, we may consider that milks from cow and sow provide calcium the absorption of which is settled after their respective content of total phosphorus and lactose. Opposed effects of these inhibitors and activators of calcium absorption compensate so that calcium from these milks is just a little better utilized by adult rat than calcium from an isocalcic solution of CaCl2. Calcium from woman milk, rich in carbohydrates, poor in total phosphorus is better absorbed than that from the two latters, however less than we might expect from its high lactose content. We may wonder that calcium utilization from cow milk is as moderate as that of a solution of CaCl2. But skeleton mineralization which may be fulfilled by milk is made better because of that: it is not chloride but calcium phosphate which ensures this mineralization, a phosphate which alone would impair this mineralization without the compensative role of lactose.