The objectives of this project were to determine the effects of harvest maturity, packaging, and storage conditions on subsequent fruit quality of Actinidia arguta ‘Ananasnaya’ and to investigate the use of edible coatings to improve fruit quality and storage life. The influences of harvest maturity (6.0, 8.7, 9.1, and 15.1%...
The primary purpose of this study was to try to (1) provide information on the chemical nature, including turbidity formation, of polygalacturonic acid in different concentrations of NaCl solution. (2) use turbidity formation characteristics to develop an assay for determining the activities polygalacturonic acid depolymerases by using a polyelectrolyte. (3)...
In 2003 and 2004 vigor zones were delineated in two commercial vineyard
sites based on vine growth variation to assess fruit and wine phenolic chemistry. In
2004, the effects of shading on the accumulation of phenolic compounds were also
investigated. Model extractions were done from the shading experiment and the...
Hop derived bitter compounds, including alpha-acids, reduced and non-reduced iso-alpha-acids, were evaluated for their contribution to peak bitter intensity in lager beer. Alpha-acids are the precursors to the major bittering components in beer (iso-alpha-acids). Typically, alpha-acids do not survive the brewing process, but if a product is dry-hopped, they may...
The thermal denaturation of proteins has been extensively studied using several methods including differential scanning calorimetry (DSC). A custom-built optical system was used to study thermal effects on protein as an alternative method to DSC measurements. It was used to investigate the thermal stability of bovine serum albumin (BSA) with...
Representing the most common flavonoid consumed in the American diet, the flavanols and their polymeric condensation products, the proanthocyanidins, are regarded as functional ingredients in various beverages, whole and processed foods, herbal remedies and supplements. Their presence in food affects food quality parameters including astringency, bitterness, sourness, sweetness, salivary viscosity,...
Raspberries have been popular since the time of the ancient Greeks. Red raspberries are cultivated throughout the world, particularly in the Pacific Northwest region of the United States and Canada. The raspberry bushy dwarf virus (RBDV) causes significant reduction in yield and crumbly fruit in raspberries, blackberries and raspberry-blackberry hybrids....
The objectives of this project were to evaluate the efficacies of electrolyzed oxidizing (EO) and ozonated waters as antimicrobial agents for enhancing the microbiological safety of fresh strawberries (Fragaria x ananassa). The influence of sodium chloride (NaCl) concentrations used for preparing EO water was evaluated on their bactericidal activities against...
Oysters are filter-feeding bivalves, which filter water for nutrients and often accumulate contaminants and human pathogens such as Vibrio parahaemolyticus and Vibrio vulnificus naturally occurring in the marine environment. These naturally occurring pathogens have been frequently isolated from raw shellfish, particularly oyster, in the United States and are recognized as...
The literature available on the silica content of herbaceous biomass, and its relative mobility in leaching/extraction systems, includes studies that have employed several different methods for silica quantification. This makes comparison of the data difficult. The objective of this thesis research was to determine the quantitative relationships between the measured...
Proanthocyanidins are a grape-derived phenolic class of compound that provide wine with bitterness and astringency. Because of this, proanthocyanidins are considered to be essential components of wine quality. Proanthocyanidins are localized in the seed, skin and stem tissue of the grape berry and the composition of proanthocyanidins will vary depending...
The effects of the residual salt of surimi on biochemical and physical properties as affected by various freeze and thaw cycles were examined. Fresh Alaska pollock (Theragra chalcogramma) surimi was mixed with 4.0% sugar, and 5.0% sorbitol, along with eight combinations of salt (0.4, 0.6, 0.8, and 1.0 % NaCl)...
Cereal and commercial grass-seed straws are abundant plant biomass materials that are currently being considered for application in industrial processes aimed at the production of biofuels, biomaterials, and biochemicals. The carbohydrate fraction of these straws is of particular interest in this context due to its chemical functionality and relative ease...
Many climatic factors influence grape berry composition including nutrient status, water availability, biotic stress, sun exposure and temperature. Previous research examined the effects of many factors listed above and much progress has been made. It is often difficult, however, to separate effects that typically confound each other, such as sun...
The phenolic profile of pineapple juice was analyzed by reverse-phase HPLC/Diode Array Detector, and 9 major peaks accounting for 70% of total peak area were characterized. None of these peaks are represented by the pineapple phenolics reported to be present by previous workers. Most of the major peaks are not...
English sole (Parophrys vetulus) is a flatfish found in abundance in the Pacific Ocean and is part of the Pacific Northwest's and California's commercial trawl fishery. Stock levels of this fish are at all time highs but there are decreased landings due to low demand and acceptability. With new regulations...
Scombroid poisoning, caused by histamine intoxication, is one of the most prevalent illnesses associated with seafood consumption in the United States. The illness is usually accompanied with a variety of symptoms, such as rash, nausea, diarrhea, flushing, sweating, and headache. Incidence of scombroid poisoning has been consistently reported in the...
The following two projects have been carried out to clarify the impact of these foam stabilizers, and to compare their foam stabilizing power to one another as well as the cling ability. The first project investigated the impacts of four commercially available hop- derived foam stabilizers; iso-alpha-acid (Iso), rho(dyhydro)-iso-alpha-acid (Rho),...
High hydrostatic pressure (HHP) affects the pH of weak acids due to an increased degree of acid dissociation while under pressure. The temporary pH reduction by high pressure in such a case may influence the barotolerance of microorganisms. The objective of this study was to determine the impact of weak...
Myoglobin (Mb) was extracted from Pacific sardine and added to Pacific whiting surimi to measure its effects on protein gelation. The purity of Mb extract was determined by SDS-PAGE. Mb extracted using ethanol showed higher purity than Mb extract using ammonium sulfate. The addition of 0.2% Mb significantly reduced breaking...
Flavonols and ellagic acid compounds were characterized and measured in 55
experimental and commercial red raspberry juices by high performance liquid chromatography (HPLC) and diode array spectral techniques. Samples were prepared
using Polyamide-6; a fraction eluted with methanol contained <_ 8 quercetin-glycosides,
quercetin and kaempferol. Another fraction, eluted subsequently with...
Thermal stabilization of chlorophyll and anthocyanin on pear peels during thermal process was investigated in this study. The green color of peels-on thermally processed (canned) pears was successfully retained by complexation of magnesium-free chlorophyll with zinc ions, and the red pigments were stabilized through anthocyanin-stannous complexation and polymerization of pear...
Yeast mannoproteins released during the process of aging wine on the yeast lees have been reported to make important contributions to wine quality. However, few mannoproteins have been identified in wine and their lifespan during aging is unknown. As a first step towards better understanding the contributions of yeast mannoproteins...
The milk fat globule membrane, a major component in buttermilk, contains many complex lipids known to be involved in a variety of biological processes. Phospholipids, including sphingolipids, exhibit antioxidative, anticarcinogenic, and antiatherogenic properties and have essential roles in numerous cell functions. Filtration coupled with supercritical fluid extraction (SFE) may provide...
A low, but significant, fraction of the carbohydrate portion of herbaceous biomass may be composed of fructose/fructosyl-containing components (“fructose equivalents”); such carbohydrates include sucrose, fructo-oligosaccharides, and fructans. Standard methods used for the quantification of structural-carbohydrate-derived neutral monosaccharide-equivalents in biomass are not particularly well suited for the quantification of fructose equivalents...
Alpha acids are found in the lupulin glands of hops cones. These acids have no bitterness of their own, but can be isomerized and subsequently hydrogenated to form bitter iso-α-acids and tetrahydroiso-α-acids respectively. Current literature values for the detection thresholds of iso-α-acid and tetrahydroiso-α-acid in lager beer have been reported...
To satisfy the desires of consumers in global markets for new products, it is essential that the cross-cultural differences in product acceptance are understood. An important aspect in cross-cultural research is the measurement tool of product acceptance. The most common scale for acceptance testing is the 9-point hedonic scale that...
Frozen blueberries were pilot-plant-processed into juice and concentrate by 2 treatments (heat and SO2), and a control. Qualitative, and quantitative anthocyanin and polyphenolic content were monitored after each processing step. Major losses occurred after the initial processing steps. Juice processing by-product contained a substantial amount of anthocyanins and polyphenolics (>42%...
The study of carbonation perception is limited, even though carbonated beverages are very popular. A series of experiments
were conducted to determine the sensory properties of carbonation itself and its interaction with other sensory modalities.
First, the power functions of carbonation in carbonated spring water were developed by a trained...
Vibrio parahaemolyticus is a seafood-borne pathogen that can cause gastroenteritis in humans. This study investigated the effectiveness of refrigerated seawater (5°C) depuration on reducing V. parahaemolyticus in raw Pacific oysters (Crassostrea gigas). Raw Pacific oysters were inoculated with a mixed culture of five clinical strains of V. parahaemolyticus and depurated...
The objective of this project was to investigate the effects of refrigeration storage and processing technologies on the quality and nutraceutical benefit of blackberries. 'Marion' and 'Evergreen', the two major blackberry varieties in Oregon, were evaluated in this study. For refrigeration storage, fresh fruit were packed in clam-shell containers right...
Albacore tuna (Thunnus alalunga) rolls were developed using two albacore meat levels and three different treatment combinations. Albacore meat levels of 82 and 88% (Alb82 and Alb88) of the total weight formulation were examined. The different treatments consisted of 0.3% sodium tripolyphosphate (STPP), 0.3% STPP plus nitrites (150 ppm), and...
Seven red raspberry (Rubus Ideaus L.) samples from Oregon, Washington, British Columbia and New Zealand were processed into juice. These, along with three juice samples supplied from West Germany were analyzed by high performance liquid chromatography, (HPLC), for nonvolatile acid, sugar, anthocyanin and anthocyanidin composition. In
order to quantitate the...
Acids contribute important flavor characteristics to
many foods and beverages. They occur naturally in these
products, arise from fermentation processes, or can be
added. Most acids taste sour. However, little is known
about their time-intensity characteristics of sourness.
This project was set forth to see if selected acids could be...
Clostridium perfringens is the causative agent of a wide variety of diseases in animals and humans. C. perfringens can produce more than 15 toxins. However, individual strains produce a subset of these toxins. Although a small percentage of C. perfringens isolates (mostly belonging to type A) produce C. perfringens enterotoxin...
New research has identified flavonols as a class of phenolic compounds which can be manipulated by both vineyard and winery practices. These phenolic compounds are key quality components of wine, affecting sensory characteristics, wine color, and wine stability. Modification of the phenolic precursors in grapes occur during fermentation and aging...
Malolactic fermentation (MLF) is important in the production of wines as it reduces acidity through the conversion of malic acid to lactic acid. However, successful MLF can be difficult to achieve due to yeast antagonism of the bacterium responsible for
the secondary fermentation, Oenococcus oeni. In particular, yeast produced sulfur...
The objectives of this study are to 1) qualitatively and quantitatively measure the odor-active compounds in ‘Marion’ blackberry; 2) compare the aroma profiles of advanced selections and new cultivars of thornless blackberry cultivars with ‘Marion’; 3) study the development of furaneol in ‘Marion’ during ripening and; 4) investigate the distribution...
High proteolytic activity Pacific whiting muscle causes hydrolysis of myofibrillar protein and lowers surimi gel quality. Although food grade proteinase inhibitors can be used to prevent autolytic activity in surimi, their usage is limited due to their adverse effects on the organoleptic quality of surimi. Cystatins however can be used...
The impact of yeast on the aroma and flavor of Vitis vinifera L. cv. 'Pinot Noir' wine was investigated. Due to the presence of naturally occurring yeast and bacteria on grapes and wine equipment, and the influence these microorganisms have on wine, a means of eliminating microorganisms from grape must...
The pigments of blackberry fruit were investigated by analytical and preparative high performance liquid chromatography (HPLC) to characterize anthocyanin patterns in commercially important blackberry (Rubus eubatus) cultivars and selections. Five anthocyanin pigments were detected in Evergreen blackberry and they were identified as cyanidin-3-glucoside, cyanidin-3-rutinoside, pentosecyanidin derivative and two acylated cyanidin...
There are seven commercially important species of salmon and trout (genera Oncorhynchus and Salmo) in North America, many of which are closely related but command markedly different prices. The purpose of this research was to provide improved and novel methods for the detection of salmon species substitution on the commercial...
Quantitative procedures were developed to determine the effect of variability in the model parameters required for the estimation of microbial shelflife and thermal processing time. Monte Carlo simulations combined with these predictive models were implemented in Microsoft Excel™. In the first study,
predictive models were used for shelf-life predictions based...
Grapes (e.g. Vitis vinifera L.) are one of the more important fruit crops from an economic standpoint with world market values over 550 million US dollars in 2007 and 2008, second to apples (United States Department of Agriculture). While a satisfactory level of ripeness is of primary concern, the quality...
Methods are described for making the following determinations in fruits and processed fruit products: anthocyanin pigment content, color density, polymeric color, browning, turbidity, and anthocyanin degradation index. Tables list the anthocyanins of common fruits, their molecular weights, molar absorbances, and wavelengths of maximum absorption. Thirty-one references are given.
Proanthocyanidins (PACs) containing A-type linkages, like those found in cranberry, have been implicated as beneficial phenolic compounds in human health, but much research is still required to better understand their activity fully. One major impediment to progress has been the existence of effective analytical methods for A-type PAC quantification. This...
A number of methods to isolate and quantify protein in Pinot noir wines were evaluated. The combination of precipitation by acetone containing 10% w/v trichloroacetic acid followed by quantification with the Bradford assay, reported in yeast invertase equivalents yielded the most accurate results when compared to micro-Kjeldahl analysis. The technique...
There is considerable interest in developing environmentally friendly processes for the economical conversion of biomass plant material to biofuels, bioproducts and biomaterials. One approach to such a conversion process is to make use of enzymes for the conversion of plant polysaccharides to simple sugars; the simple sugars could then be...
The purpose of this research was to examine the feasibility of carbon dioxide (CO2) laser perforation and its potential utilization as a novel skin pretreatment for the sugar infusion process of IQF (individually quick frozen) blueberries. In the first study, IQF blueberries were treated with varying degrees of laser perforation...