A method for the assessment of volatile compounds in dairy products
was developed using solvent desorption dynamic headspace sampling. The
method was first applied to assay for diacetyl and acetoin in buttermilk.
Major buttermilk volatiles recovered included diacetyl, acetic acid, and
acetoin. Normalized detector responses were linear over the range...
Heat resistant sporeforming psychrotrophic bacteria were
isolated from raw milk samples from 59 Grade A farms in Oregon.
Forty-nine of the 59 (83%) raw milk samples in this survey
contained sporeforming psychrotrophic bacteria; isolates from
twenty-four (40%) of the samples exhibited proteolytic properties. Populations of sporeforming psychrotrophic bacteria ranged
from...
A casein agar diffusion method was developed to detect and quantify pertinent
levels of proteinases produced in raw milk supplies by heat resistant Bacillus
sporeformers. In order to optimize the required heat treatment conditions of raw milk
samples, trials that involved a combination of different temperatures and times were
evaluated....
Several methods for estimation of the potential
shelf-life of pasteurized fluid milk products were evaluated
for their efficacy in this investigation. These methods
were evaluated and compared to sensory, biochemical and
bacteriological indices through a series of experiments
conducted on different brands of commercially pasteurized
fluid milk. The methods evaluated...
Phage-insensitive Streptococcus cremoris starter strains were
selected by assaying cheese whey against potential starter
strains. Six strains were selected and characterized for continual
use in cheesemaking. Upon phage-infection, strains were removed
from the blend. Cheesemaking continued with remaining strains. A
phage-insensitive, fast-acid-producing mutant of the infected
strain was isolated and...
The effect of reducing sodium chloride in Cheddar cheese was
studied. Milled curd from a split-lot was salted at selected NaCl
concentrations and analyzed through aging by sensory and rheological
tests. Estimation of differences in compositional analysis, lactic
acid populations, degree of proteolysis, water activity, and pH were
also determined....
A consumer and a trained descriptive panel was utilized to
determine liking ratings and flavor profiles, respectively, for
commercial brands of pre-stirred yogurt. Once the consumer and
descriptive panel data was collected, the data was combined to
determine the interrelationship of these two sets of data and to
determine the...
Microgard, a commercially-available pasteurized
fermented milk, was found inhibitory to gram negative
bacteria such as Pseudomonas putida, some well-known foodborne
pathogens (e.g. Salmonella, Yersinia and Aeromonas)
and some fungi as revealed by an agar incorporation assay
method. Gram positive bacteria, however, were not
inhibited. Rather, some bacteria in this group...
Published June 1975. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published October 1980. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Published December 1975. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Organoleptically, flavored yogurts appear to contain lower
levels of acetaldehyde than plain yogurt. This study was undertaken
to seek the reasons for this phenomenon by focusing on the analyses
of acetaldehyde production by yogurt culture bacteria in yogurt base
containing added sucrose and by performing other analyses such as
the...
A sample of 243 Willamette Valley households participated in
personal interviews and kept 7-day records of all foods brought into
the household but not consumed by human household members. Their
reason for discarding the foods, the amounts of discard, and their
assessment of the safety of the foods were compared...
Eight foodborne pathogenic and spoilage Gram-positive bacteria were
evaluated for their spontaneous resistance frequencies to the peptide
antimicrobial nisin. In brain heart infusion (BHI) medium, nisin resistance
frequencies were in the range of l06 to l08 when exposed to nisin at
concentrations 2 to 4 times the minimal inhibitory concentrations....
Several lactic acid bacteria (LAB) of the Lactococcus, Lactobacillus,
Leuconostoc and Pediococcus genera were screened for inhibition of
food-borne pathogens and spoilage microorganisms in raw milk and
dairy products. Listeria monocytogenes was killed by Lactococcus
lactis subsp. lactis and Pediococcus pentosaceus due to their
production of bacteriocin-type inhibitors. Staphylococcus aureus...
Lysozyme is a natural antimicrobial agent that is effective against many
food spoilage and pathogenic microorganisms by disintegrating their cell walls.
Immobilization of lysozyme has attractive applications for use in the food
industry: (1) The enzyme could be readily separated from treated foods and
beverages and re-used while the foods...
The purpose of this study was to identify antimutagens in yogurt active against the
experimental colon carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Our
initial experiments showed that acetone extracts of yogurt, or milk fermented by various
lactic acid bacteria were antimutagenic against MNNG and 3,2'-dimethyl-4-aminobiphenyl
(DMAB) in the Ames test (Salmonella typhimurium TA...
Bacteria use milk nutrients that remain on your dairy equipment to grow and multiply between milkings. The most important step in reaching top milk quality is to remove all milk residues (or “soil”) after each milking.
Published December 1973. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The tendency for certain single- and mixed-strain lactic
starter cultures to develop a fruity and/or fermented off-flavor
in ripening Cheddar cheese was traced to certain strains of
Streptococcus lactis in the starter. A very intense fruity and/or
fermented flavor developed in experimental cheeses when one particular
S. lactis strain was...
Published May 1993. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Discusses how to choose the best type of animal for your needs and briefly mentions issues related to feeding and breeding. Provides information on safely using milk, either fresh or in butter, yogurt, or animal feed.
People living in the suburbs and owning a small acreage often select dairy cattle or dairy goats as a means of harvesting and using their forage. Milk production can reduce the family grocery bill. Goats, especially, will help control brush and weeds and keep the area from becoming unsightly.
Published June 1965. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The adoption of modem agricultural technologies in Bangladesh increases
overall agricultural productivity and income primarily through the increase in cereal
crop production. It, however, impedes the productivity of several other minor crops
and fishes, widens the distribution of income between the rich and the poor, exploits
resources and obstructs the...
Three commercial sausage starter cultures were grown in
an internal-pH-controlled medium (PHASE 4) and in a soluble
phosphate-buffered medium. The cultures were tested by
comparing viable counts before and after freezing at -40 C
or freeze-drying and subsequent storage for 3 months in the
frozen or dried state. Strains varied...
The public expects and deserves
a safe food supply. This
includes food free of antibiotic
residues. Congress has empowered
the Food and Drug Administration
(FDA) to examine and
closely monitor the use of animal
drugs in dairy herds across the
nation. This regulatory agency has
the power of enforcement action.
Effects of different tillage systems on nitrate-nitrogen
accumulation in a 120 cm profile and on soil structure in the top 30 cm
of the profile were studied under a fallow-wheat rotation.
Treatment effects on nitrate-nitrogen, soil moisture and soil
aggregation were measured.
Fallow tillage treatments consisting of bare fallow, stubble-mulch...
The "cotton fur" (CF) condition in mink has been shown through
investigations at Oregon State University to have three basic causes,
viz.: 1) Feeding diets of fish comprising certain species of the cod
family, including: Pacific hake, Atlantic whiting and Alaskan pollock;
2) Inclusion of rancid fats in the diet;...
The travel cost method of deriving demand and value of recreation
does not include fixed costs of recreational durable goods purchases
or allow for supply restrictions on the number of suitable
sites available. The omission of these two real-world situations
results in derivation of demand curves which are more inelastic...
The concept of ecosystem management requires that management prescriptions account for economic and environmental goals that are measured in non-commensurate units. This study examines the economic and environmental trade-offs associated with planting a riparian buffer in trees to reduce stream temperatures in the Mohawk watershed, Oregon. The detrimental effects of...
This study was conducted to determine the relationships among the
linear type traits of rump angle, rump width, rump length, rear legs
side view, rear legs position, rear legs rear view, tailhead, vulva
angle, mobility, pasterns, foot angle, and toes with reproductive
performance (days open and times bred) in Holstein...
The yellow discoloration in canned oysters, which appeared after several months of storage, has been proven to be due to carotenoid pigments which were contained in the liver of the oyster. It was found after making carbon disulfide extractions of the liver and of the discolored tissue from canned oysters...
The Quartzburg District is seven miles north of Prairie City ineast-central Grant County, Oregon. The District is in a pre-Tertiarywindow of volcanic, plutonic, and sedimentary rocks ranging fromPermo-Triassic to Eocene-Oligocene in age. The Permo-TriassicDixie Butte volcanics consist of thick basalts and andesites with minorvolcanic breccias and intercalated argillite, chert, and...
Full Text:
, Oregon
AN ABSTRACT OF THE THESIS OF
FLOYD RAYMOND JOHNSON for the degree of MASTER OF SCIENCE
in
Seedling root fluorescence (SRF) has been used as a test in the USA since 1941 to discriminate Italian ryegrass (Lolium multiflorum Lam.) from perennial ryegrass (L. perenne L.). Generally, roots of Italian ryegrass fluorescece when exposed to ultraviolet light, while roots of perennial ryegrass do not. Presence of fluorescent seedlings...
Laboratory studies were conducted on the food consumption, growth, and bioenergetics of juvenile coho salmon (Oncoynchus kisutch) held at various swimming velocities and dissolved oxygen
concentrations at 15 C. Food consumption and growth of salmon fed to repletion on housefly larvae (Mus domesticus) were reduced by increasing activity at and...
New teaching techniques are the products of a wide
spectrum of research. The final test of all teaching
techniques, however derived, is their application to
a given classroom situation. The purpose of this study
is to determine whether the "principle approach", a
relatively new teaching method in agriculture, has been...
Out of 53 queens captured for initiating colonies in the
laboratory, 33 laid eggs (62 percent), 29 of these produced colonies
(55 percent), and 14 produced queens (26 percent). A behavioral model
depicts the activities of queens from spring emergence through colony
development. A discussion of its application to bumble...
The Chelan Valley is one of several valleys located on the eastern slope of the Cascade Mountains contributing to the leadership of Washington in apple production. Since the nature of the activity in the Chelan Valley is typical of all these producing areas,it was selected as a case study of...
A study was conducted to determine effects of year and season on diet quality of beef cattle grazing northern Great Basin rangelands from 1990 to 1993. Forage quality was high early in the growing season, then declined as seasons progressed (P<.05). Plant chemical composition was higher early in the growing...
Oakland is a quiet, peaceful little town on the Calapooya Creek surrounded by rolling hills and little valleys. This little booklet is written with the intention of preserving the history of our pioneers and contains a number of the names of the people who took doriation Land Claims and is...
This publication is a comprehensive account of major Federal
programs and policies relating to conservation and
development of water and related land resources and to water
pollution control in the years 1961 to 1970. It discusses most
relevant Federal legislation and the functioning of Federal and
federally-assisted programs involving research,...
Douglas-fir seedlings were inoculated with different species of
ectomycorrhizae-forming fungi in order to test the concept that
ectomycorrhizae enhance the drought tolerance of seedlings and to
investigate the mechanisms responsible for this effect.
Seedlings were transplanted at age 6 to 8 weeks into pots
containing pasteurized loam soil and inoculated...
Purpose: The general problem was to determine the relationship between biorhythms and injuries to college football participants representing Oregon State University. Procedures: The population consisted of one hundred and ninty two football players representing Oregon State University who participated in the intercollegiate football seasons of 1981 and 1982. Injury data...
Published September 1965. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Portland Public School District and in particular Jefferson High School are examined in a functionalist framework to determine
the extent to which they meet community needs. B. Malinowski's functionalist theory is employed to analyze desegregation and integration policies and actions of the Portland Public School District and Jefferson High School,...