Milk, lactose

La.ctose, Lactose [63-42-3] (milk sugar), 20, makes up about 5% of cow s milk. Lactose is a disaccharide composed of D-glucose... 

Another common disaccharide is lactose, the sugar found in milk. Lactose is a dimer of glucose and galactose, a monosaccharide that is identical to glucose except that the positions of the H and OH groups at carbon atom 4 are switched. 

An important source of galactose in the diet is the disaccharide lactose present in milk. Lactose is hydrolyzed to galactose and glucose by lactase associated with the brush border membrane of the small intestine. Along with other monosaccharides, galactose reaches the liver through the portal blood. 

Uses Control of D, esp aft antibiotic th apy Action R laces nl intestinal flora Dose Adults Peds >3 y. 1 packet, 1-2 caps, or 4 tabs daUy-qid Caution [A, +] Contra Milk/lactose aU gy Disp Tabs, caps SE Flatulence EMS None OD Unlikely to cause life-threatening Sxs... 

Case A (f) Lactase in the intestinal mucosa hydrolyzes milk lactose to glucose and galactose, so the levels of these sugars increase transiently after milk ingestion. This increase would not occur in a person lacking lactase the patient would show symptoms of lactose toxicity. The patient should exclude lactose (milk) from the diet (treatment 3). 

Many adults are unable to metabolize the milk sugar lactose and experience gastrointestinal disturbances if they drink milk. Lactose intolerance, or hypolactasia, is most commonly caused by a deficiency of the enzyme lactase, which cleaves lactose into glucose and galactose. 

Aimar et al. [19] noted that in the UF of complex liquids, such as cheese whey, which contains proteins, salts and casein fragments, concentration polarization, and adsorption and cake formation play a role in flux behavior during crossflow filtration. They may induce osmotic pressure in the retentate side since the chemical potential of the solute-rich polarized layer is lower than that of the permeate, and therefore at equilibrium, a positive osmotic pressure develops in the retentate to equal that of the permeate. The smaller the solute, the greater is its contribution to the osmotic pressure of the liquid, so that in milk, lactose and the minerals have the biggest contribution to osmotic pressure. In skim milk or whey, the osmotic pressure is around 7 bar (700 kPa) and this must be exceeded in RO to commence permeation in UF, only the proteins contribute to the osmotic pressure, which increases exponentially with protein concentration [56]. In any case, a TMP greater than the osmotic pressure is required for solvent to flow from the retentate side to the permeate side. This leads to the reduction in the effectiveness of applied TMP as driving force to permeation. 

A variety of dietary sugars may eirhance the rate of calcium absorption, though the mechanism of this effect remains unclear (Schuettc et af., 1989). This effect has brought attention to the sugar in milk (lactose) as a nutrient that can enhance calcium absorption. This effect of lactose is not unique other sugars can produce the Same effect. 

Malabsorption of monosaccharides can also cause intestinal symptoms more commonly attributed to maldigestion of disaccharides. Glucose-galactose malabsorption is also inherited as an autosomal recessive trait. Symptoms occur in the affected neonate as soon as milk (lactose) is taken, but also follow ingestion of glucose- or galactose-containing... 

The main saccharide of milk is lactose. During heat treatment of milk, lactose is involved in Maillard reactions. Lactose is used for the production of baby formulas, low-caloric foods, bread, drugs, and microbiological media. 

Vilotte, J.-L. (2002). Lowering the milk lactose content in vivo Potential interests, strategies and physiological consequences. Reprod. Nutr. Dev. 42,127-132. 

Early refeeding as tolerated is recommended. The AAP guidelines recommend age-appropriate diet resumption as soon as dehydration is corrected. Breast milk, lactose-free soy formula, and cow s... 

The enzymes shown in Figure 13.13 participate in mammary gland in the synthesis of lactose in milk. Lactose is formed from UDP-Gal plus glucose by lactose synthase, in the presence of the protein ot-lactalbumin. The endergonic synthesis of UDP-Gal in this tissue proceeds smoothly... 

Lactose synthesis in milk Lactose synthase Galactosemia... 

Conversion to glucose-6-phosphate (phosphoglucomutase) Lactose synthesis in milk Lactose synthase Galactosemia... 

Lactose (LAK-tose) is a white, odorless, sweet-tasting solid commonly known as milk sugar because it occurs in the milk of many animals, primarily the mammals. The lactose content of milk ranges from about 2 to 8 percent in cows and 5 to 8 percent in human milk. Lactose occurs in two isomeric forms, a-lactose and P-lactose, with the latter somewhat sweeter than the former. The alpha form tends to occur as the monohydrate,... 

The study of volatile diacetyl retention (BP 88°C) in various constituents of milk (lactose, fat, proteins) during spray-drying showed the importance of amorphous/crystalline ratio in lactose for aroma retention that is in tnm linked to glass transition phenomena, temperature, and water/RH. The presence of microcrystals in drops (concentration, fast drying) may be a barrier to diffusion of volatile molecnles, therefore increasing the retention in the final spray-dried powder. 

Sharif, A., Ahmad, T., and BUal, M. Q. 2007. Estimation of milk lactose and somatie cells for the diagnosis of sub-ehnieal mastitis in dairy buffaloes. Int. J. Agric. Biol. 9 267-270. 

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