Survival of Listeria monocytogenes in apple, orange, red grape, and white grape juice was evaluated. A six-strain cocktail of L. monocytogenes was used to inoculate (approx. 7 log cfu/ml) fruit juices, which were stored at 4, 10 and 24°C for up to 61 days. Inoculated red grape juice was stored for up to 5 hours only. Samples were withdrawn at appropriate intervals, neutralized with 1.0 N NaOH, serially diluted in 0.1% peptone water, and surface plated onto Tryptic Soy Agar + 0.6% Yeast Extract (TSAYE) and Modified Oxford Agar (MOX), followed by incubation at 32°C for 48 hours. When L. monocytogenes was no longer detected by direct plating, samples were enriched for L. monocytogenes using Listeria Enrichment Broth (LEB), followed by isolation on MOX. L. monocytogenes remained viable in white grape, apple, and orange juices for up to 12, 24 and 61 days, respectively. Over time, recovery of Listeria on TSAYE versus MOX was not significantly different (P>0.05), indicating that limited acid-injury developed during storage. The results of this study demonstrate the ability of L. monocytogenes to survive in apple, orange, and white grape juices during refrigerated and abusive storage conditions. Therefore, measures to prevent or eliminate L. monocytogenes in the fruit juice-processing environment are necessary to ensure the safety of juice products for public consumption. / Master of Science

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

In the theoretical part of my thesis I am dealing with marketing planning, segmentation, targeting and positioning of a product in general. Further the marketing tools such as price, product, distribution and communication are introduced. The new chosen product cider is described together with its history, production and all famous cider brands around the world. The analytical part is introduced by the market survey, by the choice of a suitable supplier (cider making company located abroad) and by the analysis of the competitors. Finally the target group is presented together with the creation of the marketing mix for this particular product.

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

No description available.

Hard cider is an alcoholic drink made from fermented crushed fruit, typically apples. The popularity of this fermented alcoholic beverage has been on the rise within the last decade. Historically, hard cider has been deemed safe due to the presence of ethanol and the low pH. Although there is lack of scientific evidence to prove that hard cider will and can be safe from foodborne pathogens. Escherichia coli O157:H7, Salmonella spp., and Listeria monocytogenes are three predominate foodborne bacterial pathogens of concern in the food and beverage industry. Escherichia coli O157:H7 in particular has been associated with fresh produce and more specifically apples, and apple products such as apple juice. The purpose of this study was to determine the bactericidal effects of pH, ethanol, and malic acid on Escherichia coli O157:H7, Salmonella spp., and Listeria monocytogenes to evaluate the safety parameters for safe hard cider production and storage. The fate of foodborne pathogens in cider was determined during hard cider fermentation, in a cider model system, and in commercial cider. Escherichia coli O157:H7, Salmonella spp, and Listeria monocytogenes did not survive a 5-day fermentation period resulting in a > 7 log CFU/mL reduction of each pathogen with no significant change in pH. The final ABV of the cider at the end of the 5-day fermentation was 4.4%. In the cider model system, the lower the pH and higher the ABV the quicker die off was observed, at pH 2.8, 3.0, 3.2, and 3.4 with 7, 8, and 9% ethanol concentration there was a 6.6 log reduction in E. coli O157:H7 population after 1 day. By the 7-day incubation period, no pathogens were detected at all pH and ABV combinations except for at pH 3.6 and 3.8 with 4% ethanol having ≤0.6 log CFU/mL of the population surviving. Similar E. coli O157:H7 inactivation patterns were observed in the model system and in the commercial ciders. The six commercial ciders observed had varying pH, ABV (%), and malic acid concentrations but successfully resulted in a > 6 log CFU/mL reduction in population of E. coli O157:H7 within 4 days of incubation. The ciders with the highest ABV’s, 8.7 and 9.6% observed a > 6 log reduction by 1 day. It was observed that at some point in time pH plays a bigger role in the presence of less ethanol, but it is clear that ethanol and pH work synergistically to kill of pathogens present in cider fermentation, a cider model, and commercial cider.

Phenolics are critical to the sensory attributes and health benefits of hard cider due to their contribution to the flavor, mouthfeel, and antioxidant activity. With the increase in demand for cider, the use of dessert apple varieties has become more common leaving ciders lacking in phenolics. However, a promising method to increase their phenolic content is through maceration with apple pomace. This study evaluated the effect maceration with apple pomace during cider fermentation on the extraction of phenolic compounds, as well as its effect on the sensory properties of the final product. For this study, ciders were fermented with 0% (control), 20%, 35%, and 50% of the average pomace created during production of the apple must. After fermentation, the ciders were analyzed for acid content, total phenolic content (TPC), alcohol by volume (ABV), color, volatile profile, and sensory properties. The ciders fermented with apple pomace went through malolactic fermentation. During the maceration phenolics were extracted which resulted in an increase in phenolic content in cider. Compared to the control, the treatment ciders were also seen to have higher ABV and TPC, lower acidity, and a different aromatic profile: decreased acetaldehyde and increased ethyl acetate, isoamyl alcohol, and phenylethyl alcohol. The color measurements suggests that treatment ciders were lighter, with a higher red and yellow color compared to the control cider. The sensory analysis revealed the treatment ciders were perceived as less acidic and astringent, but more bitter than the controls. This study shows the addition of apple pomace in its native state increases total phenolic content and could be favorable to produce well rounded ciders. This study shows maceration is a promising technique for increasing phenolic content in ciders.

Though the cidermaking process is very similar to that of winemaking, there is a lack of scientific knowledge as to how orchard management practices and fruit storage affect the quality of the resulting cider. This research examined how both varying harvest maturities and post-harvest storage temperatures and durations in apple cultivars Dabinett, Brown Snout, and York impacted fruit quality as well as the chemistry of the juice and cider. Harvest intervals of two weeks before maturity, at maturity, and 2 weeks after maturity resulted in significant differences in fruit quality and juice chemistry, but few of these differences persisted in cider chemistry. Nonetheless, differences in concentration of some individual polyphenols determined by UPLC-MS were observed in ciders made from fruit harvested at different stages. For example, cider made from optimally mature Dabinett had over 250% the concentration of procyanidin B5 that was found in cider made from fruit harvested earlier or later. The storage treatments also resulted in substantial differences in fruit and juice chemistry, but fewer differences in cider chemistry. As with the harvest maturity experiment, differences in individual polyphenols were detected, with ciders made from cv. York having 20% higher epicatechin concentration when stored for 6 weeks at 1°C rather than 10°C. Finally, the accuracy of the Folin-Ciocalteu (FC) assay, commonly used for quantification of total polyphenols in fruit juices and fermented fruit beverages was critically evaluated. Reducing sugars in the sample matrix did not affect the results of the FC assay, whereas the presence of the amino acid tyrosine resulted in significant overestimation of total polyphenols in fruit juice by the FC assay. / Master of Science in Life Sciences

Cider production volume has increased over 800% in the past 5 years in North America. This rapid growth of the cider industry coupled with traditional craft approach to cider making necessitates increased research on apple chemistry, processing, and fermentation strategies for cider production. A common problem in cider is the sulfur off-aromas production by yeast during fermentation. Fermentation of cloudy juice is often associated with sulfur off-aromas in white wine production; therefore, pre-fermentation juice clarification is an important and routine step in white winemaking practice. However, cider makers are often reluctant to clarify juice pre-fermentation due to beliefs that pre-fermentation juice clarification will reduce the concentration of yeast assimilable nitrogen (YAN) and polyphenols; thus, negatively impacting cider quality. In this study, different clarification methods were applied on York apple juice, and both raw and clarified juices were fermented into cider. The impact of pre-fermentation juice clarification treatments on the juice and finished cider chemistry was assessed by comparing the primary juice and cider chemistry, YAN concentration and amino acid composition in juice, polyphenol concentration and composition in juice and cider. Different clarification treatments affected the YAN concentration and amino acid composition differently. Polyphenol concentration in juice was decreased and individual polyphenol composition was different after the clarification (p<0.05), but these changes did not persist into the finished cider. The effect of pre-fermentation juice clarification on sensory properties of cider warrants further investigation. Future research should also include the development of appropriate analysis for polyphenol measurement in apple juice and cider. / Master of Science in Life Sciences

The US cider market has expanded in recent years, but limited research-based information is available on fermentation management. This study investigates how apple cultivar and yeast inoculation affect the chemical and sensory properties of cider. Four ciders were produced in triplicate using combinations of two different apple cultivars - Harrison, a cider cultivar and GoldRush, a dessert cultivar - and two fermentation strategies - inoculated with dry active yeast EC1118 or Pied de Cuvé ambient fermentation. Ciders were analyzed for alcohol content, free/total SO2, titratable acidity, volatile acidity, malic acid, pH, and residual sugar. Sensory evaluation was conducted using Descriptive Analysis with trained panelists. Results were analyzed via ANOVA and Principal Component Analysis. Apple cultivar and fermentation method resulted in significant differences for chemistry and sensory parameters. Malic acid concentration was greater in the control ciders while concentrations of both residual sugar and volatile acidity were higher in the PDC ciders. The interactions effect of cultivar*fermentation method influenced both malic acid and residual sugar concentrations, where concentration differences between control and ambient ciders is smaller for GoldRush than for Harrison, showing that fermentation style produces different results across cultivars. Volatile acidity produced opposite interaction effects as differences between fermentation styles was larger for GoldRush. For sensory attributes, Harrison ciders produced high intensities for multiple attributes, but also higher variability. Multiple sensory descriptors displayed interaction effects as the fermentation method produced different results in different cultivars. This study demonstrates that increasingly popular practices in the industry can produce significantly different ciders. / Master of Science in Life Sciences / The US cider market has grown rapidly in recent years, with many new products entering the market. However, there is limited research-based information available on cider fermentation management. This study investigates how production variables, namely apple cultivar and yeast inoculation, affect the chemical and sensory properties of the cider created. The overall goal of this project is to assess the chemical and sensory characteristics that come from cider production treatments. In this study, four experimental ciders were produced using combinations of two different apple cultivars – Harrison, a cider cultivar and GoldRush, a dessert/fresh market cultivar – and two fermentation management strategies – inoculated with dry active yeast strain EC1118 or indirect inoculation through a natural fermentation method. Ciders were analyzed for alcohol content, free and total SO2, titratable acidity, volatile acidity, malic acid, pH and residual sugar. Sensory evaluation was conducted by a trained panel providing descriptive terms and intensities for each sample. Both chemical and sensory results were analyzed to reveal significant differences in samples based on not only apple type and inoculation method, but also the interactions between those two variables. This study demonstrates that increasingly popular practices in the cider industry – like natural fermentation or the use of cider-apple varieties – can produce significantly different ciders. This highlights the idea that producers need to treat each apple cultivar differently, as they behave differently throughout production.