Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: Titus O. Awokuse, Dept. of Food & Resource Economics. Includes bibliographical references.

Background: Type 2 diabetes mellitus is one of the most prevalent chronic diseases worldwide, currently affecting about 3 million global populations. The incidence of Type 2 diabetes has been increasing particularly in recently developed Asian settings including Hong Kong. Dairy product, as a part of dietary guidelines, has been hypothesized to help reduce risks of Type 2 diabetes. However different types of dairy product might have different effects on Type 2 diabetes given their varying content in fat, sugar and vitamins. Objective: To review literature on the examination of the association between consumption of different types of dairy products (total dairy, high-fat dairy, low-fat dairy and fermented dairy) and the risk of type 2 diabetes Methods Relevant studies were searched and identified through database of PubMed and Google Scholar using combination of keywords. Studies examining the association between consumption of total dairy and subtypes of dairy products and the risk of type 2 diabetes were included. Results: Of the 163 papers identified, 10 studies were finally included in this systematic review. All studies were prospective cohort study from Western countries. Findings for different kinds of dairy products varied. For high-fat dairy products consumption, nine out of the ten studies found there was no association with type 2 diabetes risks. For low-fat dairy products, six out of ten studies found an inverse association after adjusted for confounders like age, sex and total energy intake; among these six studies, three still reported an inverse association after further adjusted for confounders like education level, smoking status and alcohol intake, physical activities and family history of type 2 diabetes. For fermented dairy products (mainly yoghurt), among seven studies which examined this, three studies found an inverse association between yogurt consumption and Type 2 diabetes risk before and after adjusted for multivariate confounders (age ,sex, total energy drink, education level, social class, physical activities, smoking status, alcohol intake and family history of type 2 diabetes, etc) . One of the three studies also found that, other than yogurt, there was an inverse association between low-fat fermented dairy and total fermented dairy consumption and type 2 diabetes risks after adjusted for age and sex. However, after further adjustment, the association became null for total fermented dairy products while it remained for low-fat fermented dairy products. All of the 10 studies that examined subtypes of dairy product also reported total dairy product consumption. For total dairy product, six out of ten studies found an inverse association. Conclusion: Overall, total dairy consumption might be associated with lower risks of type 2 diabetes, but the associations may be varied by subtypes of dairy products. Across different types of dairy products, low-fat dairy consumption was associated with lower risk of type 2 diabetes while high-fat dairy consumption was clearly not associated with type 2 diabetes risk. Results for subtypes of fermented dairy consumption remain unclear. Further prospective cohort study in other non-Western populations may provide are required. / published_or_final_version / Public Health / Master / Master of Public Health

The development of synthetic culture flavors for use in dairy products such as sour cream, cottage cheese, butter, and buttermilk has created the need for a rapid quantitative analysis for the synthetic flavor concentrates. An internal standard gas chromatographic method has been developed which is capable of +10% accuracy for each flavor compound in single sample analyses. The separation of water, acetaldehyde, dimethyl sulfide, acetic acid, diacetyl, propylene glycol, and acetone (the internal standard) was performed with a column consisting of a 1/8 inch OD section of stainless steel tubing 10 feet in length packed with 120-150 mesh Porapak Q plus a stainless steel precolumn 1/8 inch OD and 10 inches in length packed with 120-150 mesh Porapak R. The column was operated isothermally at 155°C with a flow rate of 44 ml per min of nitrogen carrier gas. A flame ionization detector was used. In the course of the investigation, Porapak Q (available from Waters Associates Inc., Framingham, Mass.) was evaluated. The optimum mesh size under the conditions employed was the 120-150 mesh range. The efficiency of Porapak Q columns, as reflected by the number of theoretical plates per foot for n-propanol and the resolution of n-propanol and iso-propanol, was found to increase when the column diameter was increased from 1/16 inch OD to 1/8 inch OD to 1/4 inch OD. / Graduation date: 1967

Acetaldehyde is known to be responsible for the green or yogurt-like flavor defect of lactic cultures. This study was undertaken to extend the knowledge of acetaldehyde production and utilization by microorganisms normally found in mixed-strain butter cultures. It is anticipated that the resulting information will contribute to a more thorough understanding of the development of a green flavor defect; hence, to methods of avoiding and overcoming this defect. Acetaldehyde production by single-strain cultures of S. lactis, S. cremoris, and S. diacetilactis was found to parallel the increase in microbial population. S. lactis and S. cremoris were found to remove some of the acetaldehyde produced on continued incubation at 21°C. S. diacetilactis did not remove any of the acetaldehyde produced. The ratio of diacetyl to acetaldehyde in the strains of S. diacetilactis studied was found to be unfavorable for a good culture flavor at all times up to 22-24 hr incubation. All of the cultures studied produced a distinct green flavor when grown in milk media. All of the lactic streptococci studied produced both ethanol and acetone when grown in a boiled milk medium. No evidence of acetone utilization by S. diacetilactis was observed. A tentative mechanism for the formation of acetone from pyruvate via acetoacetate was proposed. Single-strain cultures of Leuconostoc dextranicum and Leuconostoc mesenteroides were shown to be capable of utilizing added acetaldehyde under a variety of culturing conditions. These two organisms, along with L. citrovorum were combined into two-strain mixtures with various lactic streptococci. The production and utilization of acetaldehyde varied widely among different two-strain mixtures. The ratio of different lactic organisms comprising the flora of a desirably flavored commercial mixed-strain butter culture was determined. The microbial shift occurring when this culture developed a green flavor defect was found to be an overgrowth of the homo-fermentative lactic streptococci by the S. diacetilactis population. It was found that the concentration of acetaldehyde in a ripened single-strain lactic culture could be significantly reduced by adding a large inoculum of a culture of L. citrovorum and continuing incubation at 21°C or by cooling and holding the culture at 5°C after the addition of L. citrovorum. / Graduation date: 1966

Graduation date: 1962

Thesis (Ph. D.)--University of Wisconsin, 1930. / Without thesis note.

Thesis (Ph. D.)--University of Wisconsin, 1930. / Without thesis note.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xii, 113 p.; also includes graphics. Includes bibliographical references (p. 99-113).

Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.A. in economics)--Washington State University, August 2009. / Title from PDF title page (viewed on Sept. 15, 2009). "School of Economic Sciences." Includes bibliographical references (p. 18-20).