abstract: Drinking vinegar is a popularly discussed remedy for relieving heartburn symptom, as can be read on many websites; however, there has been no scientific research or theory to support its efficacy. This randomized, placebo-controlled, double-blind, cross-over research study tested the efficacy of the organic apple cider vinegar, with mother, on alleviation of the heartburn symptom related to Gastro-esophageal reflux disease (GERD). A minimum of one week separated the four trial arms: chili (placebo), antacid after chili meal (positive control), vinegar added to chili, and diluted vinegar after chili meal. Twenty grams of vinegar were used in both vinegar treatments, and 10 grams of liquid antacid were used in the antacid trial. A five-point Likert scale and a 10-cm visual analogue scale (VAS) were used to assess heartburn severity during a 120 minutes testing time. Seven of 15 recruited subjects' data was usable for statistical analysis (age: 39.6 ± 12.2 y, body mass index (BMI): 29.4 ± 4.2 kg/m2, waist circumference: 36.4 ± 4.1 inch). There was no statistically significant difference among the mean and incremental area-under-the-curve (iAUC) heartburn scores among different trials (Likert scale questionnaire p= .259, VAS questionnaire p= .659, iAUC Likert scale p= .184, iAUC VAS p= .326). Seven participants were further divided into antacid responder (n=4) and antacid non-responder groups (n=3). Likert scale mean heartburn score and iAUC data in antacid responder group had significant finding (p= .034 and p= .017 respectively). The significance lay between antacid and 'vinegar added to chili' trials. Effect size was also used to interpret data due to the small sample size: Likert scale: mean heartburn score= .444, iAUC= .425; VAS mean heartburn score= .232, iAUC .611. Effect size for antacid responder group was Likert scale: mean heartburn score= .967, iAUC= .936. Future research is needed to examine whether ingesting organic vinegar benefits alleviation of heartburn symptom related to GERD for people who do not respond well to antacid. / Dissertation/Thesis / Masters Thesis Nutrition 2016

Three studies regarding Escherichia coli O157:H7 in apple cider were conducted. The objectives were: to evaluate the effectiveness of wash and sanitizers for removing E. coli O157:H7 from apples; to survey cider producer practices; and to determine the efficacy of ultraviolet light for reducing E. coli O157:H7 in cider. Apples with a five-strain acid resistant mixture of E. coli O157:H7 were treated with 200 ppm hypochlorite, a phosphoric acid-based fruit wash, 5% acetic acid, 5% acetic acid followed by 3% hydrogen peroxide, a peroxyacetic acid-based solution, and distilled water. The water wash caused insignificant reductions. All other treatments caused significant reductions. Acetic acid and peroxyacetic acid were the most effective with reductions of 3.1 and 2.6 logs, respectively. The survey determined that most producers are small, seasonal operations. Most use sound orchard management practices, clean and sanitize daily, sort and wash apples, use refrigeration, and try to prevent contamination. However, some use drop and damaged apples. Few use chemical sanitizers on apples, preservatives, pasteurize cider, or have HACCP programs. Cider inoculated with the same mixture of E. coli O157:H7 was processed using a thin- film ultraviolet disinfection unit operating at 254 nm. Dosages ranged from 9,402 to 61,005 æW- sec/cm2. Treatment significantly reduced E. coli O157:H7 (pó 0.0001) with a mean reduction of 3.81 log CFU/ml. Reduction was also affected by the level of background microflora in cider. Results indicate that ultraviolet light can reduce this pathogen in cider. However, additional reduction measures are necessary to achieve the required 5 log reduction. / Master of Science

Dissolved oxygen has previously been shown to affect the colour and sensory properties of red and white wine during storage. A number of different wines and wine based sparkling ciders are made at Kiviks Musteri AB. The aim of this work is to study the effects of dissolved oxygen and different enological treatments on sensory quality and colour of red wine and sparkling apple cider during storage at different temperatures. The effects of fermentation and fining on foaming ability of pear wine are also studied.   Samples of red wine were taken after different processing steps such as pumping, sulphuration, pasteurization and filling. To evaluate the effects of the processes on the wine, dissolved oxygen, colour and free SO2 were measured in each. Measurements were also made on samples of red wine stored at either 38°C or room temperature for different amounts of time. Sensory evaluations were also made of the wine samples. Colour was measured by measuring absorbance at 420, 520 and 620 nm. Dissolved oxygen was also measured after different processing steps during production of apple cider. To study the effects of dissolved oxygen on cider, three different batches of apple cider were produced, with different concentrations of dissolved oxygen. The samples were stored at either 38°C or room temperature for one week. Measurements of absorbance at 420 nm and free SO2, along with sensory evaluation were made on the cider samples before and after storage. Fermentation and fining of pear wine were made in small scale and the foaming ability was compared to that of large scale factory produced wine.   Pumping and filling had negative impact on the flavour of red wine. Colour intensity increased while free SO2 decreased during storage of red wine. The sensory quality decreased during storage and a higher storage temperature had a distinctive impact on this decrease. Dissolved oxygen had no noticeable effect on changes in sensory properties of neither red wine nor cider during storage. A higher concentration of dissolved oxygen was correlated to a higher increase in colour intensity of red wine though. A higher decrease was also seen in free SO2 in red wine samples with higher dissolved oxygen content when stored at 38°C. Fermentation had a large impact on foaming properties of pear wine. Small scale wine fermentation resulted in much lower foaming ability than large scale fermentation. / Syrehalten i viner har i tidigare studier visat sig kunna påverka både färg- och smakförändringar i vinerna under längre tids lagring. På Kiviks Musteri AB i Skåne produceras en mängd olika sorters vin och vinbaserade cidrar. Målet med den här studien är att studera vilken effekt syrehalten har på smak och färg i viner och cidrar från Kiviks Musteri som får lagras i olika temperaturer. Effekten av olika processteg under produktionen studeras också. Slutligen studeras även hur skumbildningen i päronvin påverkas av jäsning och klarning av vinet.   Prover av rödvin togs efter de olika processtegen vinet genomgår på Kiviks Musteri. Proverna lagrades olika länge i antingen 38°C eller rumstemperatur. Färgstyrka och smak analyserades på proverna före och efter lagringen. Syrehalten analyserades också i proverna direkt efter att de tagits och svavelhalten i proverna analyserades före och efter lagringen för att mäta hur mycket proverna oxiderades under lagringen. Mätningar av syrehalt gjordes även efter olika processteg under produktionen av äppelcider på Kiviks Musteri. Vilken effekt syrehalten har på äppelcider studerades genom att tre olika satser äppelcider med olika syrehalt tillverkades. Prover från dessa lagrades en vecka i antingen 38°C eller rumstemperatur. Därefter analyserades färgstyrka, svavelhalt och smak på proverna. Hur skumbildning i päronvin påverkas av jäsning och klarning studerades genom att päronvin fick jäsa och klarnas antingen i stor skala i musteriets tankar eller i liten skala på ett laboratorium. Skumbildningen mättes genom ett test där vinprover blandades med kolsyrat vatten.   De processer som inverkade starkast på smaken på rödvin var pumpning och tappning, vilka gav tydliga smakförsämringar. När rödvin lagrades så minskade svavelhalten medan färgstyrkan ökade. En försämring av smaken skedde också under lagringen, särskilt när vinet lagrades i 38°C. Syrehalten hade ingen tydlig påverkan på smaken av vare sig rödvin eller äppelcider. Syrehalten i rödvin hade däremot ett svagt samband med ökningen i förgstyrka i rödvin. Syrehalten hade även ett samband med minskningen av svavelhalten i de prover av rödvin som lagrades i 38°C. Skumbildningen i päronvin påverkades väldigt starkt av jäsningen, medan klarningen hade begränsad effekt. Skumbildningen var vesäntligt mycket lägre i päronvin som jäst i liten skala på laboratoriet än i det vin som jäst i musteriets tankar.

The Virginia cider industry has grown rapidly in the past decade, and demands research-based recommendations for cider fermentation. This study evaluated relationships between the unique chemistry of apples and production of hydrogen sulfide (H2S) in cider fermentations. Yeast assimilable nitrogen (YAN) concentration and composition and residual fungicides influence H2S production by yeast during fermentation, but these factors have to date only been studied in wine grape fermentations. This study surveyed 12 Virginia-grown apple cultivars and found that the majority were severely deficient in YAN. The effects of three fungicides on cider fermentation were investigated; elemental sulfur, fludioxonil and fenbuconazole. Fenbuconazole adversely impacted fermentation kinetics. Sulfur and fludioxonil marginally impacted fermentation kinetics. Sulfur increased H2S production, but fludioxonil and fenbuconazole did not affect H2S production. There was no difference in fermentation kinetics and H2S between nitrogen sources arginine (approximating grape), asparagine (approximating apple) and ammonium (YAN supplement). Supplementation with methionine resulted in increased fermentation rate and decreased H2S production. The detrimental effects of fenbuconazole and beneficial effects of methionine were diminished with increasing total YAN. Contrary to previous findings, the most H2S was formed at 153 mg/L YAN which is above the generally recommended minimum to prevent H2S formation. These results indicate that apple juice chemistry may influence yeast metabolism during cider fermentation, in ways that have not been previously studied in grape fermentation. Our findings indicate the need for and contribute to the development of targeted fermentation management practices for cidermaking. / Master of Science in Life Sciences

Hazard Analysis Critical Control Point (HACCP) regulations for juice manufacture require the application of a process that will result in a 5-log reduction (99.999%) of the pertinent pathogen in the juice being processed. The use of ultraviolet (UV) light, as an alternative to traditional thermal processing, has been adopted by some juice processors as a means of meeting the HACCP 5-log performance standard. However, little research had been performed to determine the effect of UV when used in combination with antimicrobial agents that are commonly added to juice products. Therefore, the objectives of this work were (1) to determine if chemical preservatives and ultraviolet light have a combined effect on the reduction of Escherichia coli in apple cider, and (2) to determine the influence of adding chemical preservatives at different points in the processing of juice (i.e., either prior to or after ultraviolet light processing) on the reduction of Escherichia coli in apple cider. In this study, refrigerated (4°C) pasteurized apple cider that contained no added preservatives was inoculated with E. coli ATCC 25922, a surrogate strain for E. coli O157:H7, and exposed to UV (peak output: 254 nm). The following chemical preservatives were added to apple cider either prior to or after UV exposure: dimethyl dicarbonate (75 and 150 ppm), hydrogen peroxide (75 and 150 ppm), potassium sorbate (1000 and 2000 ppm), and sodium benzoate (1000 and 2000 ppm). Following UV exposure and chemical preservative application, inoculated juices were stored at 4°C for 72 hours. Samples were collected prior to and immediately after UV exposure and at 24, 48, and 72 hours of storage. At each sampling point, juice portions (0.1 ml) were serially diluted in peptone diluent (0.1%) and surface plated onto Tryptic Soy Agar (TSA). Counts of the bacterial colonies were made 48 hours after incubating plates at 35°C. Overall, reductions of E. coli were greater in cider treated with preservatives after UV processing than when preservatives were added prior to UV processing (P < 0.05). Furthermore, dimethyl dicarbonate and hydrogen peroxide were more effective than potassium sorbate and sodium benzoate in reducing E. coli populations in conjunction with UV (P < 0.05). When added prior to UV exposure, potassium sorbate was the least effective, allowing for the greatest survival (P < 0.05). This study describes the use of UV in conjunction with hydrogen peroxide and dimethyl dicarbonate as an effective method for producing a 5-log or greater reduction of E. coli O157:H7 in apple cider. / Master of Science

Naturally occurring food antimicrobials such as plant essential oils are receiving tremendous interest as intervention systems to enhance microbiological safety and quality. Poor water solubility of essential oils makes it difficult to incorporate them in foods, impacting visual appearance, antimicrobial effectiveness, and possibly organoleptic properties. Engineered nanoscale delivery systems can principally solve these challenges, but those based on low-cost food ingredients and inexpensive and scalable processes are currently scarce. This dissertation presents a simple and scalable two-step technology to prepare nano-delivery systems. The first encapsulation step, based on emulsion-evaporation, involves preparing emulsions composed of an oil phase with thymol or eugenol, major compounds in extracts from thyme and clove respectively, in hexane and an aqueous phase with conjugates of whey protein isolate and maltodextrin, followed by evaporation of hexane by spray drying. The second step is to hydrate spray dried capsules to enable the formation of nanoscale particles. The encapsulation performance and dispersion characteristics were affected by amounts and types of conjugates (ratio of protein: maltodextrin and maltodextrin chain length), volume fraction and composition of the oil phase. The optimal conditions corresponded to 55.8 % encapsulation efficiency and 12.6 % loading for thymol and 47.9 % encapsulation efficiency and 7.9 % loading for eugenol. Dispersions prepared from the identified capsules contained particles smaller than 100 nm and were transparent at pH 3.0-7.0 and 0-50 mM before and after heating at 80°C for 15 min. Nano-dispersions and free oil were tested for antimicrobial activity against Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Salmonella typhimurium. Nano-dispersed and free antimicrobials had similar effectiveness at various pH and temperatures in tryptic soy broth and apple cider, while in 2 % reduced fat milk, nano-dispersed antimicrobials were consistently more effective than unencapsulated ones. Therefore, the commercially viable nanoscale technology presented in this study enables the delivery of lipophilic antimicrobials for enhanced microbial safety and quality, without compromising visual appearance of foods, especially clear beverages.

<i>Cryptosporidium parvum</i> is a protozoan parasite historically associated with waterborne and more recently foodborne outbreaks of diarrheal illness. Contamination of certain foods, such as unpasteurized apple cider, with infective oocysts may occur as oocysts are shed in the feces of common ruminants like cattle and deer that graze in and around orchards. Cryptosporidiosis can result in a severe illness for previously healthy individuals and a life-threatening illness in immunocompromised individuals. Disease occurs after the ingestion of small infective oocysts (4 to 5 mm in size). The relatively thick membrane of the oocysts allows them to be resistant to chlorine and many other environmental pressures, making oocysts difficult to inactivate. In this study, alternative treatments to pasteurization were evaluated for their ability to inhibit <i>C. parvum</i> oocyst viability in fruit juices. Oocyst viability was analyzed with a cell culture infectivity assay, using a human illeocecal cell line (HCT-8) that is most similar to human infection. The percent inhibition of infection by each treatment was determined along with the corresponding log reduction for the treatments found to be most effective. Infection by treated oocysts was compared to that of control untreated oocysts. Cell monolayers were infected with 10⁶ treated oocysts or a series of 10-fold dilutions. Parasitic life stages were visualized using an immunohistochemistry system and 100 microscope fields counted per monolayer. Organic acids and H₂O₂ were added on a wt/vol basis to apple cider, orange juice, and grape juices. Malic, citric, and tartaric acids at concentrations from 1%-5% inhibited <i>C. parvum</i> infectivity of HCT-8 cells by up to 88%. Concentrations ranging from 0.025%-3% H₂O₂ were evaluated where addition of 0.025% H₂O₂ to each juice resulted in a >5 log reduction of C. parvum infectivity as determined with an MPN-based cell culture infectivity assay. Treating apple cider, orange juice, and grape juice with ozone for a time period of 30 seconds up to 15 minutes at 6° and 22°C (0.9 g/L flow rate) inhibited C. parvum viability to > 90% as monitored in the cell culture assay. It is hypothesized that oocyst wall proteins that are necessary for infection are oxidized by the reactive oxygen species generated from the decomposition of the ozone and hydrogen peroxide treatments. These treatments or combinations thereof may offer potential alternatives to traditional pasteurization for fruit juices to successfully inhibit <i>C. parvum</i> viability. / Ph. D.

Les composés phénoliques sont impliqués dans les propriétés organoleptiques majeures des aliments dérivant d’une matrice végétale. Ils sont notamment responsables de l’amertume, de l’astringence et de la couleur des produits cidricoles. Le brunissement observé lors de la transformation des fruits est lié à la formation de pigments jaunes-orangés. Il est initié par l’activité d’une enzyme plastidiale, la polyphénol oxydase, qui catalyse l’oxydation des polyphénols en présence d’oxygène. Cela aboutit à la formation de quinones, espèces chimiques très réactives qui sont rapidement impliquées dans des voies réactionnelles ultérieures. Certains produits néoformés sont colorés. Un profilage des molécules colorées présentes dans quatre jus de pomme monovariétaux aux couleurs contrastées a été réalisé en CLHP-DBD-SM. Il a mis en évidence l’existence de tannins oxydés colorés et de composés jaunes-orangés non tannants. Parmi ces derniers, des produits d’oxydation de la phloridzine, dérivant de la classe des dihydrochalcones, ont été clairement identifiés (POPj, XGPOPj). Des approches couplées en milieu réel et solution modèle ont en outre permis d’identifier une nouvelle structure colorée dérivant d’un couplage oxydatif entre une dihydrochalcone et un flavanol monomère. Enfin, des déhydrotrimères d’épicatéchine ont pu être caractérisés en solution synthétique mais n’ont pas été détectés directement dans les jus. Par ailleurs, la couleur exprimée par les pigments formés peut subir des modulations en fonction de l’environnement physico-chimique. A titre d’exemple, la fermentation cidricole génère classiquement une décoloration des moûts ; or la composition du milieu fermentaire évolue sous l’influence de différents paramètres tels que le pH ou le potentiel redox. L’impact d’un milieu réducteur sur la couleur du POPj et d’une déhydrotriépicatéchine de type A, sélectionnés comme pigments modèles des jus de pomme, a été exploré par voltammétrie cyclique et spectroélectrochimie UV-visible. En outre, les changements de propriétés spectrales du POPj liés à son état de protonation ont été rationalisés par des approches de TD-DFT. / The phenolic compounds are involved in the main organoleptic properties of plant-derived foods. They are especially responsible for the bitterness, the astringency and the color of apple cider products. The browning observed during fruit processing is related to the formation of yellow-orange pigments. By its catalytic activities, the polyphenol oxidase, a plastidial enzyme, initiates the oxidation of polyphenols in the presence of oxygen. It leads to the formation of quinones, very reactive species which are quickly involved in further chemical reactions. Some of the neoformed products are colored. Four apple juices, showing contrasted colors, were analyzed by reversed-phase HPLC-DAD-MS in order to obtain their profiles in colored compounds. The presence of yellow-orange oxidized tanning and non-tanning compounds was highlighted. Within the latter compounds, some phloridzin oxidation products, deriving from dihydrochalcones, were clearly identified (POPj, XGPOPj). In parallel, coupled approaches in real media and model solutions led to the identification of a new colored structure deriving from an oxidative coupling between a dihydrochalcone and a flavanol monomer. Finally, catechin trimers were also characterized in synthetic medium but they were not detected directly in apple juices. Moreover, the color expressed by the yellow-orange pigments can suffer some variations as a function of the physical-chemical environment. For instance, the cider fermentation results generally in a loss of color in apple juices; but the composition of the fermentative medium evolves under the influence of several parameters, such as pH and redox potential. The impact of reducing conditions on the color of POPj and A-type dehydrotriepicatechin, both selected as model pigments of apple juices, was explored by cyclic voltammetry and UV-visible spectroelectrochemistry. Besides, the changes in spectral properties of POPj, related to its protonation state, were rationalized by TD-DFT calculations.