Heat pasteurization

AHP = anhydrous heat pasteurized DH = dry heat MA = moist atmosphere SD = solvent detergent SHP = solvent heat pasteurized. 

Modest doses of radiation have been shown to inactivate the few residual yeast in heat-pasteurized beer. The major problem here involves flavor and odor. Breweries in common with all branches of beverage-alcohol manufacture jealously guard these features as being of prime importance (J3). 

Microbiological tests have indicated that penicillin G is stable to heat. Pasteurization temperatures and times commonly applied to milk and milk products are inadequate for inactivation of tlie antibiotic if it is present (26-29). At 71 C, a total of 1705 min was required to inactivate completely penicillin G in milk, whereas at boiling temperatures or above, all data indicated that a portion of tire penicillin activity in milk survived boiling for 60 min or autoclaving at 15 psi steam pressure for 15-30 min (26, 29). Milk from treated cows retained some of its antimicrobial activity even after conversion to dried skim milk powder (30). 

Stability studies have shown azaperone to be quite stable upon heating. When samples of kidney, liver, bacon, and injection sites from pigs treated with azaperone were heat-pasteurized, no losses of the concentrations of the parent dmg and its main metabolite, azaperol, occurred (107). 

I thiamine) and C (ascorbic acid) are partially destroyed by heal, while Bj, and Bn, are relatively heat-stable. Vitamin B iribollavin) is heat-stable but it is quickly destroyed by light. In spite of the varying sensitivity of the w ater-soluble vitamins toward heat, pasteurized milk is a good source of all the milk vitamins except C. 

Since viral inactivation methods, such as solvent detergent and heat pasteurization, were implemented in the production process, the risks of HIV and hepatitis have virtually been ehminated. Dry heating at 60 C is insufficient to eliminate all hepatitis C virus, which requires dry heating at 80 C, pasteurization, or treatment with mixtures of solvents and detergents (14). Nevertheless, many viral inactivation methods currently used do not completely eliminate certain (non-enveloped) viruses, for example parvovirus and hepatitis A (11,15) removal of the small, non-hpid-enveloped parvovirus B19 requires 15 nm nanofiltration. HIV appears to progress more rapidly in patients co-infected with hepatitis B and cytomegalovirus (11). In addition, hepatitis C rephcated more rapidly in patients infected with HIV (11). 

Several different plasma-derived factor VEI products are avaUable (see Table 100 ). These products are derived from the plasma of thousands of donors, and therefore potentially can transmit infection. Donor screening, testing plasma pools for evidence of infection, viral reduction through purification steps, and viral inactivation procedures (e.g., dry heat, pasteurization, and solvent detergent treatment) have all resulted in a safer product. No cases of HIV transmission from factor concentrates have been reported since 1986. However, there have been isolated reports of hepatitis C infection with the use of plasma-derived products. Additionally, there have been outbreaks of hepatitis A viral infections associated with plasma-derived products, likely because solvent detergent treatment does not inactivate this nonenveloped virus. Parvovirus has also been reported to be present in both plasma-derived and recombinant factor VIII products. " Finally, there remains concern about the possibility for infection with as yet unidentified viruses that currently used methods would not inactivate. 

Yeom, H.W., Streaker, C.B., Zhang, Q.H., and Min, D.B. 2000a. Effects on the quality of orange juice and comparison with heat pasteurization. Journal of Agricultural and Food Chemistry 48 4597 605. 

Heat pasteurization is an effective means of biological stabilization, but flavor is affected. The bouquet of a good wine is highly susceptible to heat. The vintner goes to great lengths to protect his wine from oxidation, and heat accelerates it. In addition, elevated temperatures can result in precipitation of proteins to form haze. 

Osmotic dehydration has been utilized for developing intermediate moisture fruits stabilized solely by control with added antimycotic preservative, as well as SSP with higher stabilized by a combination preservation technique involving and pH control plus heat pasteurization, due to simplicity of the operations involved, economy, and low-energy inputs. 

Microbial contamination of the solution comes from different sources but its water activity 0.90-0.95 limits the growth of nonosmotolerant bacteria and yeasts. Processing of fruits and vegetables results in contamination of osmotic solution with moulds, yeasts, and lactic bacteria. Reported microbial loads of osmotic solution range from 10 to 10 cfu/mL after long-time use [158]. Mild heat pasteurization is sufficient to lower the microbial load of the solution to value as low as 102 Cfu/mL [161]. 

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