Age thickening

Age thickening is a common defect of UHT sterile milk concentrate, which has received less drastic heat treatment than conventionally sterilized evaporated milk (Harwalker 1982). Age thickening is promoted by high milk solids content, addition of alkali to raise the pH, and addition of citrate, phosphate, and other anions that lower the Ca ion activity. Conversely, addition of Ca ions improves stability of the product against age thickening. 

In addition to the flavour defects initiated or influenced by damage to the fat globule membrane, such damage also results in a variety of physical defects in milk and especially in cream. The more important of these are oiling-off , cream plug and age thickening . 

Age thickening is due essentially to a high level of free fat, especially in high-fat creams the product becomes very viscous due to interlocking of crystals of free fat. 

The gene defective in cystic fibrosis codes for CFTR (cystic fibrosis transmembrane condnctance regulator), a membrane protein that pumps CP out of cells. If this CP pump is defective, CP ions remain in cells, which then take up water from the surrounding mucus by osmosis. The mucus thickens and accumulates in various organs, including the lungs, where its presence favors infections such as pneumonia. Left untreated, children with cystic fibrosis seldom survive past the age of 5 years. 

Hypertrophic cardiomyopathy (HCM) is characterized by abnormal left ventricular thickening. The left ventricular septum is the most common site of involvement. Pathologically, the disease is characterized by myocardial fiber disarray. The myocardium may exhibit extensive scarring and disorganization of interstitial and intercellular tissue (Elstein et al., 1992). The severity of HCM depends on the age of the patient, as well as the extent of the disarray. Patients with HCM have variable... 

Phaeococcomyces exophialae forms slimy, mucoid, slow-growing, smooth colonies that are grayish black. Budding yeast cells which are at first subhyaline are abundant. With age, some of the cells become darker, with thickened cell walls. Some pseudohyphae usually are present. Hyphal development may become dominant in some isolates of this species with subsequent subculture. 

Gastro-oesophageal reflux in infants is common and tends to resolve at 12-18 months of age. Simple procedures, such as posture and thickening of foods, may help to alleviate gastro-oesophageal disease in infants. 

Children reflux symptoms in infancy generally resolve spontaneously by the age of 18 months, but may require feed thickening or the use of alginates More severe symptoms require specialist advice and may need treating with proton pump inhibitors. 

A potentially fatal lung toxicity occurs in 10 to 20% of patients receiving bleomycin. Patients particularly at risk are those who are over 70 years of age and have had radiation therapy to the chest. Rarely, bleomycin also may cause allergic pneumonitis. Bleomycin skin toxicity is manifested by hyperpigmentation, erythematosus rashes, and thickening of the skin over the dorsum of the hands and at dermal pressure points, such as the elbows. Many patients develop a low-grade transient fever within 24 hours of receiving bleomycin. Less common adverse effects include mucositis, alopecia, headache, nausea, and arteritis of the distal extremities. 

Sedimentation tests are of value particularly for rapid evaluation of the effects of aging, flocculants, vibration, and any other variables that conceivably could affect a rate of filtration. The results may suggest what kinds of equipment to exclude from further consideration and what kind is likely to be worth investigating. For instance, if sedimentation is very rapid, vertical leaves are excluded, and top feed drums or horizontal belts are indicated or it may be indicated that the slurry should be preconcentrated in a thickener before going to filtration. If the settling is very slow, the use of filter aids may be required, etc. Figure 11.1 illustrates typical sedimentation behavior. Figure 11.2 summarizes an experimental routine. 

White or cream-colored powder, or filaments, grains, or granules. Slighl odor and taste. Insoluble In water insoluble in adds, bui soluble in alkaline solutions. It is used in pharmaceutical products as a food additive as a thickening age ll and stabilizer in ice cream, cheese products, canned fruits, and sausage casings also used in synthetic fibers. 

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