Stable retorted whey protein beverages with 5% protein concentration were prepared. The effect of protein concentration, fat concentration and homogenization pressure on the heat stability and the stability of emulsions of sterilized whey protein beverages was determined. Beverages containing >1% protein formed aggregates during the heat treatment. Food grade additives were added to the beverages with >1% protein to determine if the heat stability could be improved. Lecithins and polyphosphates improved the heat stability while hydrocolloids decreased the heat stability. Lecithins improved the heat stability of emulsions better than polyphosphates but polyphosphates were more effective in beverages without fat. Lecithins modified by acetylation or hydrolysis provided more protection against heat denaturation of proteins than regular lecithin. Acetylated lecithin created the emulsions most stable against creaming. Improvement in the emulsion stability by the use of phospholipids was associated with a more negative charge at the interface of the fat droplets. The effect of polyphosphates on the heat stability was related to the chain length of the polyphosphates. Short chain polyphosphates (dp~4) were more effective than other polyphosphates. Polyphosphates probably improved the heat stability of the systems by changing the structure of water and this prevented aggregation of whey proteins. Hydrocolloids decreased heat stability most probably through thermodynamic incompatibility that locally increased the concentration of proteins and promoted aggregation during the heat treatment.The effect of homogenization pressure, concentration of acetylated lecithin, and the concentration of short chain polyphosphate on the storage stability of retorted whey protein beverages containing 5% protein and 3% fat was determined. The creaming index and particle size index changed over 28 d of storage and indicated creaming of the emulsions. The use of homogenization pressures of 55 and 90 MPa compared to 20 MPa reduced the magnitude of the change of the particle size index and creaming index during storage. Inclusion of polyphosphates reduced the storage stability of the emulsions. Optimization of parameters showed that emulsions formulated with 5% protein, 3% fat and 0.3% lecithin without polyphosphates and homogenized at 90 MPa had the best stability after 28 d of storage.

Thesis--Harvard, 1944. / Includes bibliographical references (p. 355-363).

Thesis--Helsinki. / Summary in English. Includes bibliographical references.

Thesis--PlanA (M.S.)--University of Wisconsin--Stout, 2003. / Includes bibliographical references.

Thesis (M.A.)--York University, 1999. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 99-114). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ56176

<p>&quot / Traditionally brewed beers are of cultural and economic importance to many African nations. The presence of mycotoxins in African beer is a topic that needs to be addressed, since most African countries have a climate of high humidity and temperature that favours the growth of moulds. Mycotoxins challenge not only the health of animals and humans, but also the economy, especially in underdeveloped countries where contamination is most likely. Literature proves that mycotoxins depict various effects on the immune system including immunotoxicity. Beer analysis is therefore of utmost importance in order to evaluate organoleptic characteristics, quality, nutritional value as well as safety. The aims of this study involve the analysis and comparison of traditional and commercial beer in terms of physical characteristics, mycotoxin concentrations as well as effects on specific immune pathway biomarkers in order to elucidate possible immunotoxicity...&quot / </p>

The corrosion behaviour of pure copper, zinc and aluminum in selected commercial beverages was studied. Experiments were also conducted in the presence of citric and phosphoric acid to investigate their role in the corrosion process in these beverages. Two experimental approaches were used to investigate the corrosion behavior: a chemical method in which the dissolved metal concentration was measured after immersion of a sample in a beverage and an electrochemical method using the Tafel extrapolation technique. The metal surfaces were also examined by SEM/EDX after the immersion tests and electrochemical polarization. Among the important conclusions from this research are that the order in which the various beverages affect the corrosion rate as evaluated by Tafel extrapolation of the polarization curves did not agree with the order based on measurement of the dissolved metal concentration as determined by the immersion tests except when a 1- day immersion test was used for Al. The dissolved Al, Zn and Cu concentrations obtained from short-term immersion tests differed from those measured in long-term tests, although the same ranking of the corrosiveness of the seven soft drinks was obtained after 1- and 3- day immersion tests. These discrepancies likely stem from the complicated dynamics of the corrosion of these metals and the various physical, chemical and electrochemical processes that take place in these beverages. No simple correlation was found between the beverage properties and composition and the dissolved copper, zinc and aluminum concentrations after immersion, whether based on short-term or long-term tests. However, the corrosion rate of copper in the 7 soft drinks as determined by the Tafel extrapolation method was found to depend on the pH. Uniform corrosion was observed in all iv cases except for Al immersed in Gatorade. Pitting cavities were observed on the surface of Al after both the 5-day immersion test and Tafel polarization measurements. Of the beverages considered in this study, Gatorade was consistently found to be the most corrosive for the three test metals.

The processing parameters of and processing procedures for sweetened blueberry flavored carbonated milk beverages were developed in this study. Foam formation of the milk after carbonation was controlled by a precharging of the vessel headspace. A combination of heat treatment (85°C, 30 minutes) and CMC addition was conducted to minimize the acid coagulation of casein with added fruit concentrate. Both carbonated and noncarbonated, sweetened blueberry flavored milk were evaluated by a trained panel. The effect of carbonation and sweetener source on taste properties in a blueberry flavored milk beverage system were discussed. Carbonation enhanced the sensory rating of overall intensity, sweetness and blueberry flavor. There was no significant carbonation effect on perceived viscosity. The sweetener source (sucrose, HFCS, pear concentrate and aspartame) caused a significant effect on the sensory rating of viscosity, but a nonsignificant effect on that of overall intensity, sweetness and blueberry flavor. Two consumer panels evaluated the carbonated, sweetened blueberry flavored milk beverages. The percentage of panelists who liked the products was approximately 50%. The results from the distributions of responses on a "just right" scale indicated that the carbonation and sweetness level probably were optimum formulations, and the level of blueberry flavor was too low. The results also implied that sucrose and HFCS were more appropriate sweeteners in flavored carbonated milk beverages than aspartame and pear concentrate. Two obstacles for consumer potential were the rapid separation phenomenon and the unattractive color of the products. / Graduation date: 1988

Bibliography: leaves 247-274 / xi, 274 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1985

Thesis (Ph. D.)--University of Adelaide, 1985. / Includes bibliographical references (leaves 247-274).