Unpasteurized Juice Research Articles

Food safety risks and current practices regarding unpasteurized dairy products, juices, and ciders

Since pasteurization has become widely used, there has been a dramatic decline in foodborne illness associated with dairy products. In the United States dairy products are responsible for less than 1% of reported foodborne disease outbreaks, compared with 25% of all outbreaks in the early 1900s. Unpasteurized dairy products can pose a significant health risk because of their high protein and moisture content, which aids in the multiplication of pathogens. Although less reported, unpasteurized juices and ciders have also been associated with foodborne outbreaks. Health effects from ingestion of contaminated unpasteurized dairy products, juices, and ciders range from fever and gastrointestinal symptoms to organ failure and even death. With the exception of certain aged cheeses, pasteurization of dairy products is required under the Food and Drug Act in Canada. The distribution and sale of unpasteurized milk has been prohibited since 1991; however, personal consumption of raw milk is not prohibited. The sale of unpasteurized juices and ciders is legal in Canada. Microbial standards, labeling requirements, educational programs, nonthermal processing, and other strategies to address microbial hazards in unpasteurized dairy products, juices, and ciders should be explored to determine their efficacy and acceptability. Because of the lack of data regarding foodborne illness attributed to unpasteurized food products in Canada, the population health impacts and Canadian patterns of consumption is unknown. A better system of documenting associated outbreaks is necessary to develop a better understanding of the Canadian situation, so that current policies and practices can be further evaluated.

Injury and Viability Loss of Escherichia coli O157:H7, Salmonella, Listeria Monocytogenes and Aerobic Mesophilic Bacteria in Apple Juice and Cider Amended with Nisin-Edta

For health reasons, people are consuming fresh juices or minimally processed fruit and vegetable juices, thereby, exposing themselves to the risk of foodborne illness if such juices are contaminated with bacteria pathogens. Behavior of aerobic mesophilic bacteria, Escherichia coli O157:H7, L. monocytogenes and Salmonella cells at 104 CFU/ml in apple cider (pH 3.9) and apple juice (pH 3.6), amended with nisin (500 IU/ml)+ethylene diaminetetraacetic acid (EDTA, 0.02 M) combination treatment and storage at 5°C and 10°C for 10 days as well as 22oC for 16 h was investigated. Populations of aerobic mesophilic bacteria increased in untreated apple cider stored at 5°C and 10°C for 10 days while E. coli O157:H7, L. monocytogenes and Salmonella slightly declined. A slight increase for E. coli O157:H7, L. monocytogenes and Salmonella in juices stored at room temperature (22°C) was observed. Treatment of juices with nisin+EDTA led to higher inactivation of bacterial populations including inoculated populations of E. coli O157:H7, L. monocytogenes and Salmonella. The surviving populations determined within 10 to 30 min of treatment include 18% of injured cells. And leakage of UV- absorbing materials were higher in samples containing the injured bacteria. The injured populations did not recover during storage at 5 or 22°C. Waiting up to 4 h before refrigeration of treated samples and leaving treated refrigerated samples at room temperature for up to 4 h did not cause significant changes in microbial populations. Addition of nisin+EDTA combination in unpasteurized apple cider or apple juice as a natural antimicrobial will improve the microbial safety of the juices. However, treatment of juices with nisin+EDTA combination is still subject to regulatory approval by the FDA.

Unusual Occurrence of Staphylococcus warneri as Endophyte in Fresh Fruits along with Usual Bacillus spp

AbstractIn the present study, we obtained several bacterial isolates from direct plating (without enrichment) of the diluted extract of apples and oranges obtained from commercial market of major cities in Tamil Nadu, India. Based on the cultural growth characteristics in different selective media, the isolates were grouped into four groups. The 16S rRNA gene was amplified using universal primers. The expected amplified fragments were obtained in four isolates belonging to two culture groups and were sequenced. This resulted in the identification of Staphylococcus warneri and Bacillus pumilis in apples and B. flexus and B. subtilis in oranges. The different species of Bacillus are reported already as endophytes in plants and plant‐derived produce. However, the occurrence of S. warneri is unusual. The observation emphasizes the need to further our understanding of the changing ecology of bacteria, particularly human pathogenic Staphylococcus, which has adapted to inner tissues of fruits.Practical ApplicationIdentification and detection of human pathogenic bacteria like Staphylococcus in fresh fruits is applicable in creating awareness among the public about the route cause of foodborne illness because of consumption of unhealthful raw and unpasteurized juices. In addition, this study helps us to reevaluate the present production and handling practices of fruits. It also emphasizes the need for developing strategies based on a coordinated approach by the growers, distributors, retailers, importers and public health officials to eliminate or contain such human pathogenic bacteria in fresh fruits.

Characteristics of Consumers of Unpasteurized Milk in the United States

Despite considerable scientific evidence about the health risks of drinking unpasteurized (raw) milk, advocates continue to lobby for the reduction of state regulatory restrictions on the sale of unpasteurized milk. Multivariate analyses were performed on 1998–1999, 2002–2003 and 2006–2007 FoodNet Population Survey data to determine characteristics of unpasteurized milk consumers. Across all years of the survey, 3.4% of respondents reported consuming unpasteurized milk at some point in the previous seven days. Our findings indicate that unpasteurized milk drinkers in the states covered by the analysis are more likely to be Hispanic, less educated and of lower income than non‐drinkers and they are more likely to report drinking unpasteurized juice.

Qualitative Microbiological Risk Assessment of Unpasteurized Fruit Juice and Cider

Until recent decades, unpasteurized fruit juice and cider have been considered non-hazardous with respect to microbiological pathogens due to their acidic nature. However, in light of the many global foodborne illness outbreaks associated with these products, it is apparent that certain bacterial, viral and parasitic pathogens can survive these acidic conditions and remain infectious. Specifically, outbreaks of human illness have been attributed to infection with Escherichia coli O157:H7, Salmonella spp., Shigella spp., Cryptosporidium spp., Trypanosoma cruzi, and hepatitis A, and have been associated with the consumption of apple juice or cider, orange juice and various other types of unpasteurized juices. The most likely mechanisms by which juice, and the fruit it is processed from, becomes contaminated with pathogenic microorganisms are through direct contact with animal or human faeces, or indirect contact with contaminated water, soil, processing equipment, or infected food handlers. This risk assessment reviews foodborne outbreaks linked to unpasteurized fruit juice and cider, and evaluates the evidence for effectiveness of measures to control pathogens in these products.

Enhancement of bioconversion efficiency of limonin by Pseudmonas putida G7

The biocatalytic activity of periplasmic dehydrogenase of Pseudomonas putida G7 strain to catalyse limonin was enhanced when whole cells were permeabilized with EDTA (1 μM) lysozyme (100 μg/ml). The treated cells were entrapped in dialysis membranes to increase the stability. Permeabilized cells (1 g dry weight) entrapped in dialysis membrane could biotransform 73.67% of limonin in unpasteurized mandarin juices in a single-batch cycle of 3 h. Furthermore, permeabilized cells stored for 45 days in phosphate buffered saline (at 4 or 30°C) retained enzyme activity and were reusable for up to eight batch cycles of limonin reduction. The results of this study suggest a potential application of permeabilized P. putida G7 cells for reducing limonin levels in mandarin juices.

Survival and Growth Characteristics of <i>Escherichia coli </i> O157:H7 in Pomegranate-Carrot and Pomegranate-Apple Blend Juices

Unpasteurized fruit juice has been implicated in outbreaks of Escherichia coli O157:H7 (E. coli O157:H7). Meanwhile, certain fruit, such as pomegranate, contains antimicrobial components. The objective of this study was to investigate the survival and growth characteristics of E. coli O157:H7 on pomegranate juice in laboratory medium and in pomegranate-carrot and pomegranate-apple blend juices at different concentrations. Single strain of E. coli O157:H7 (E0019, H1730, and Cider) was inoculated into brain heart infusion (BHI) broth or a mixture of three strains was inoculated into the blended juices containing pomegranate juice. Our results showed that the addition of pomegranate juice inhibited the growth of tested E. coli O157:H7 in both laboratory medium and blended juices.The antimicrobial activity increased with increased concentrations of pomegranate juice (P < 0.001) and incubation times.The bacterial population was reduced by at least 2 log CFU/ml in BHI broth and juice blend samples in the presence of 20% and 40% Pomegranate juice respectively. Sensory evaluations performed using a 9 point hedonic scale showed significant satisfaction on using 40% pomegranate juice blend with carrot and apple juices. Our study suggests that pomegranate juice could be used as a natural antimicrobial in different food systems including juices to inhibit the growth of E. coli O157:H7.

Control of Pathogenic and Spoilage Microorganisms in Fresh-cut Fruits and Fruit Juices by Traditional and Alternative Natural Antimicrobials.

Traditional antimicrobials have been extensively used for many years. However, consumers are currently demanding wholesome, fresh-like, and safe foods without addition of chemically synthesized preservatives. The application of novel natural antimicrobials to assure safety of fresh-cut fruits and unpasteurized juices while preventing quality loss is a promising alternative. The effectiveness of these natural substances added to fruit derivatives has been studied by different researchers. Antimicrobials of animal (lactoperoxidase, lysozyme, and chitosan), plant (essential oils, aldehydes, esters, herbs, and spices), and microbial origin (nisin) can be used to effectively reduce pathogenic and spoilage microorganisms in fresh-cut fruits and fruit juices. Nevertheless, the use of these compounds at a commercial level is still limited due to several factors such as impact on sensory attributes or, in some cases, regulatory issues concerning their use. Therefore, extensive research on the effects of each antimicrobial on food sensory characteristics is still needed so that antimicrobial substances of natural origin can be regarded as feasible alternatives to synthetic ones.

Food consumption patterns in the Waterloo Region, Ontario, Canada: a cross-sectional telephone survey.

BackgroundThe demographics and lifestyles of Canadians are changing, thereby influencing food choices and food preparation in the home. Although different dietary practices are associated with increased risk of foodborne illness, our ability to evaluate food consumption trends and assess risks associated with foodborne illness is limited by lack of data on current eating habits and consumer food safety practices. The objective of this study was to describe, for the first time, the food consumption patterns in a Canadian-based population from a food safety perspective, in order to establish baseline data on actual food intake of individuals.MethodA cross-sectional telephone survey of 2,332 randomly selected residents of Waterloo Region, Ontario, Canada (C-EnterNet pilot site) was conducted between November 2005 and March 2006. Food intake was assessed using a 7-day dietary recall method.ResultsCertain food items were consumed more than others among the same food groups, and consumption of many food items varied by gender and age. Specific foods considered high-risk for the transmission of certain enteric pathogens were significantly more likely to be consumed by males (i.e. unpasteurized juice, bean sprouts, and undercooked meat) and elderly individuals (i.e. undercooked eggs). The majority of households prepared and consumed most meals at home, allocating an average of 44 minutes to prepare a meal.ConclusionBaseline data on actual food intake is useful to public health professionals and food safety risk assessors for developing communication messages to consumers and in foodborne outbreak investigations.

Shelf life of unpasteurized sour orange juice in Iran

Introduction . In Iran, sour orange is available between mid-October and March. Frequently, consumers store a large volume of unpasteurized juice at room or low temperatures for consumption when the fresh fruit is not available. The aim of our research was to determine the shelf life of unpasteurized sour orange juice which was stored under conditions similar to those adopted by consumers at home. Materials and methods . Sour orange juice was prepared by hand-squeezing fresh fruit; it was filtered, and then poured into clear or dark green glass bottles. Bottles were stored at room temperature [(28 ± 2) °C], in the refrigerator [(4 ± 1) °C] and in the freezer [(–12 ± 1) °C] for 12 weeks. Additional samples were prepared by supplementing juice with 2% (w/w) citric acid and they were stored in the refrigerator. Total soluble solids and pH values were measured every 2 weeks and analysis was carried out on ascorbic acid content by means of the titration method in the presence of 2,6–dichlorophenol indophenol. The study was performed for 12 weeks. Results and discussion . Total soluble solids content and pH value of the initial juice were 11.5 °Brix and 3.18, respectively. pH appeared not to be significantly influenced by storage time or conditions; however, total soluble solids content in a few samples was reduced to about 9.5 °Brix. The initial ascorbic acid content was 130 mg·100 mL–1 ; after 2 weeks, it was reduced by nearly 50% for all unfrozen samples. The final concentration of ascorbic acid in the juice was approximately 20 mg·100 mL–1 , regardless of storage conditions. The deteriorative reaction of ascorbic acid in the juice at each temperature experienced followed a first-order kinetic model with activation energy of 2.67 kJ·mol–1 .

JUICE AND CAROTENOID YIELD FROM PROCESSED WATERMELON

Most watermelon in the U.S. is consumed fresh. Development of value-added products from watermelon is desirable for new market niches, and provides alternative markets for fruit that are cosmetically undesirable for the fresh market. The objective of this experiment was to determine if different processing techniques changed the lycopene and quality aspects of juices and concentrates. Watermelon flesh was macerated, followed by holding at room temperature (no heat) or heating to 50 °C. Macerate was then placed in a hydraulic press to obtain juice. Adding heat to macerate increased juice yield by 1% to 2% and increased lycopene content by 1 to 2 mg·kg–1. The residual pomace (waste from juicing) also contained lycopene, about 110% of that found in the juice, or 10% from the original macerate. In a second experiment, juice was subjected to pasteurization, which caused a slight loss of lycopene and beta-carotene compared to the unpasteurized juice. In a third study, juice was concentrated to 42 °Brix using either 40 or 50 °C heat treatments, followed by pasteurization. Heating juice to 50 °C concentrated the lycopene by 17% compared to heating to 40 °C. Pasteurization increased the lycopene content of the 40 °C concentrate by 10% but not of the 50 °C concentrate. In summary, the addition of heat at various steps during processing and pastuerization of watermelon concentrated but did not degrade lycopene. Additionally, the residual pomace created from juice manufacturing is a concentrated source of carotenoids and may have potential use as a value added nutraceutical product.

Destruction of Escherichia coli O157:H7 by Vanillic Acid in Unpasteurized Juice from Six Apple Cultivars

The behavior of Escherichia coli O157:H7 in Granny Smith, Gala, Empire, McIntosh, Red Delicious, and Golden Delicious apple juice with or without supplementation with 5 or 10mM vanillic acid was examined over a storage period of 7 days at 4 and 15°C. The consequences of supplementation on sensory difference and preference were also determined by triangle testing. Juices made from the six apple cultivars had pH values ranging between pH 3.13 and 3.92. Vanillic acid exerted a concentration, pH, and time-dependent lethal effect toward E. coli O157:H7 in unpasteurized apple juice. Supplementation with 10mM vanillic acid led to a 5-logarithm reduction in populations after 7 days at both temperatures, but sensory analysis revealed significant differences from and preference for unsupplemented juices. Supplementation with 5mM vanillic acid accelerated death of E. coli O157:H7, but population reductions ranged from 5 log CFU/ml in low pH juices to none in high pH juices, particularly at 4°C. No sensory difference or preference was detected in two of the six juices at this level of supplementation.

Survival and Growth of Enterobacter sakazakii on Fresh-Cut Fruits and Vegetables and in Unpasteurized Juices as Affected by Storage Temperature

Enterobacter sakazakii is an emerging foodborne pathogen that has caused illnesses and deaths in infants and elderly immunocompromised adults. Outbreaks of E. sakazakii infection have been associated with infant formulas, but the documented presence of this pathogen in a wide variety of ready-to-eat foods, including lettuce and other raw vegetables, makes it important to learn more about its behavior in these environments. We investigated the survival and growth characteristics of E. sakazakii on fresh-cut apple, cantaloupe, strawberry, watermelon, cabbage, carrot, cucumber, lettuce, and tomato and in juices prepared from these fruits and vegetables. Produce and juices were inoculated with E. sakazakii at 2 to 3 log CFU/g and 1 to 2 log CFU/ml, respectively, and stored at 4, 12, or 25°C. Populations either did not change or gradually decreased in fresh-cut produce and juices stored at 4°C but grew at 12°C on fresh-cut apple, cantaloupe, watermelon, cucumber, and tomato and in all juices except apple, strawberry, cabbage, and tomato juices. All fresh-cut fruits and vegetables except strawberry supported growth of E. sakazakii at 25°C. Growth occurred in all juices except apple, strawberry, and cabbage juices, followed by decreases in population to <1 CFU/ml after 48 to 72 h, which coincided with decreases in pH and an increase in the population of lactic acid bacteria. Increases in total counts occurred in all juices except strawberry juice stored at 25°C and apple and strawberry juices stored at 12°C. Total counts increased in cantaloupe, carrot, cucumber, and lettuce juices stored at 4°C. Populations of molds and yeasts increased in apple and tomato juices stored at 25°C but decreased to <1 CFU/ml in cabbage, lettuce, and cucumber juices. Further characterization of the behavior of E. sakazakii on fresh produce and in unpasteurized juice as affected by commercial packaging and handling practices is needed.

Characterisation of volatile aroma compounds of orange juices by three dynamic and static headspace gas chromatography techniques

The influence of collection of volatiles by different headspace sampling techniques was compared for different orange juices, including one fresh unpasteurised, two reconstituted commercial juices and one juice freshly hand extracted in the laboratory. Dynamic headspace sampling from stirred juice samples (DH + S) and notably by purge and trap (PT) sampling gave the highest levels of analysed volatiles, but the composition of the isolated volatiles from the different types of juices varied depending on the volatiles collection method. Aroma sampling by dynamic headspace method without stirring (DH) gave results that reflected the equilibrium aroma composition as determined by static headspace better than that obtained by PT sampling. Totally, 67 aroma constituents were identified among all the orange juices. The largest amount of volatiles was isolated from the fresh commercial, unpasteurised juice, followed by the two reconstituted juices and the hand extracted juice. Limonene was the major constituent of all commercial juices comprising 72–93% of the total peak area of isolated volatiles, meanwhile its amount in the freshly hand extracted juices ranged from 25 to 62% depending on the method of isolation. Qualitatively, the aroma profiles of the freshly extracted oranges and the fresh, commercial unpasteurised juice were described by 62 and 55 aroma compounds, respectively, which included large proportions of esters and aldehydes. Only 41 and 34 aroma compounds, mainly terpenes, were identified in the reconstituted orange juices.

Potential for Internalization, Growth, and Survival of Salmonella and Escherichia coli O157:H7 in Oranges

Internalization potential, survival, and growth of human pathogens within oranges were investigated in a series of laboratory experiments. Submerging oranges into dye solutions at various temperature differentials was used to assess internalization potential. Conditions in which dye internalization was observed were further studied by applying Escherichia coli O157: H7 or Salmonella onto the stem scar, subjecting the oranges to a temperature differential, juicing, and measuring numbers of pathogens in the resulting juice. Pathogens for growth and survival studies were applied to or injected into simulated peel punctures. Oranges with small peel holes of selected sizes were also placed into solutions containing these pathogens. Bacterial survival was also evaluated in orange juice at 4 and 24°C. Oranges internalized pathogens at a frequency of 2.5 to 3.0%, which mirrored dye internalization frequency (3.3%). Pathogens were internalized at an uptake level of 0.1 to 0.01% of the challenge applied. Bacteria grew within oranges at 24°C, but not at 4°C. Thirty-one percent of oranges with 0.91-mm surface holes showed pathogen uptake, whereas 2% of oranges with 0.68-mm holes showed pathogen uptake. Pathogens added to fresh orange juice and incubated at 24°C declined 1 log CFU/ml within 3 days. These results suggest that internalization, survival, and growth of human bacterial pathogens can occur within oranges intended for producing unpasteurized juice.

Quality Parameters of Packaged Refrigerated Apple Cubes in Orange Juice

The quality of apple cubes (Red Delicious and Granny Smith) maintained in pasteurised or fresh orange juice with sucrose and chemical preservatives: acidulants (citric and ascorbic acids) and potassium sorbate or sodium benzoate, packaged in plastic films of different gaseous permeability (polyethylene (PE) and EVA-SARAN-EVA (ESE)), was analysed during storage at 10 °C. Surface colour, microbial growth and instrumental texture changes were measured. Microbial flora was identified, and its growth was mathematically modelled. Shelf-life values of 10d in polyethylene and higher than 25d in ESE film, maintaining acceptable quality attributes, were obtained for both apple varieties in pasteurised juices. For Red Delicious in unpasteurised orange juice with acidulants and potassium sorbate (0.125–0.250 g/kg), shelf-life values were 7.5–8.5d in PE and higher than 15 d in ESE film. For Granny Smith apples in unpasteurised juice without potassium sorbate, shelf-life values were 10 d in PE and higher than 15 d in ESE. Higher concentrations (0.375–0.50 g/kg) of potassium sorbate adversely affected colour. Sodium benzoate was discarded as preservative because it produced severe browning in both apple varieties. All the samples showed safe sanitary conditions; coliforms microorganisms did not grow in any of the tested conditions.

Jury Decisions and Awards in Personal Injury Lawsuits Involving Foodborne Pathogens

A study of food poisoning jury verdicts in 32 states (1988–1997) revealed that plaintiffs won awards in food poisoning jury trials 31% of the time, and received a median award of $25,560. Multivariate analyses were performed to examine the effects of various factors on food poisoning jury verdicts and on the size of the award. The odds of a plaintiff victory increased if a foodborne pathogen or illness was specified, and decreased if defendants had “deep pockets”or used medical expert testimony. Illnesses involving hospitalization, death, or chronic complications received higher awards than other illnesses.

Pasteurization of Fresh Orange Juice Using Gamma Irradiation: Microbiological, Flavor, and Sensory Analyses

ABSTRACTRecent concern about the presence of disease‐causing bacteria in unpasteurized juice has highlighted the need to develop alternative means of pathogen control that preserve sensory properties and nutrient content. The objectives of this study were to determine the effects of different doses of gamma irradiation on reducing the microbial pathogens L. monocytogenes and Salmonella enterica in fresh orange juice, and to determine whether significant reduction could be achieved without compromising sensory qualities. While irradiation was effective in destroying pathogens, the development of off flavors precludes its use as an alternative processing technology.

Outbreak of Salmonella Serotype Anatum Infection Associated With Unpasteurized Orange Juice

In March 1999, a patient was infected with Salmonella serotype Anatum after having consumed unpasteurized orange juice from a manufacturer in Florida. We conducted a cohort study among customers of the manufacturer, performed pulsed-field gel electrophoresis (PFGE) on isolates, and inspected the manufacturing plant. Surveillance data identified three additional patients infected with Salmonella Anatum showing indistinguishable or closely related PFGE patterns. Three of the four patients had consumed orange juice from the same manufacturer. In the cohort study, 6 of 68 persons (9%) who consumed orange juice and/or orange ice cream from the manufacturer were ill, compared with 1 of 47 (2%) who did not. A positive antigen test for Salmonella species and coliform growth in juice samples taken from the production line suggested contamination during the manufacturing process. Commercially produced orange juice should be pasteurized or otherwise processed to achieve equivalent reduction of pathogens.

Comparison of aqueous commercial cleaners for effectiveness in removing Escherichia coli O157:H7 and Salmonella muenchen from the surface of apples

Unpasteurized fruit juice and cider have been implicated in outbreaks of Escherichia coli O157:H7 and Salmonella infections, yet various processes used to clean and sanitize fruits before producing juice have not been thoroughly studied for their effectiveness in removing pathogens. The objective of this study was to evaluate cleaners used in the apple industry for their efficacy in removing E. coli O157:H7 and Salmonella from the surface of apples. E. coli O157:H7 was transformed with green fluorescent protein plasmid (pGFP). In addition to encoding for the production of GFP, the plasmid also encodes for ampicillin resistance. S. muenchen was adapted to grow in media containing 50 μg/ml nalidixic acid. The use of ampicillin and nalidixic acid resistant strains enabled enumeration of the pathogen without interference by microflora naturally present on apples. Unwaxed Red Delicious cv. apples were surface inoculated with 8.58 log 10 cfu of E. coli O157:H7 and 8.11 log 10 cfu of S. muenchen. Five commercial apple cleaners were applied at concentrations and exposure times recommended by manufacturers. Populations of E. coli O157:H7, S. muenchen, aerobic mesophiles, and yeasts and molds on apples treated with cleaners and water (control) were determined. Compared to washing with water, treatment with cleaners removed or killed up to 2.86, 3.11, 2.48, and 0.73 log 10 cfu of E. coli O157:H7, S. muenchen, aerobic mesophiles, and yeasts and molds per apple, respectively. There were differences in the effectiveness of cleaners in removing pathogens, but pH (2.0 and 12.0) and concentration (1% and 5%) of cleaner, and time of exposure (0.5–2 min) were not correlated with magnitude of reduction in population. The use of some types of cleaners commercially formulated for apples may contribute significantly in attaining target 5-log 10 reductions of pathogens on the fruit intended for unpasteurized juice production or the fresh produce market.