Darkening resulting from ascorbic acid (AA) degradation during storage of diced peaches packed in flexible retortable pouches was identified as an area of concern in meal ready-to-eat individual military rations. First, we tested the replacement of AA by L-ascorbyl-2-phosphate (A2P) and the potential antibrowning effect of Pycnogenol, a blend of plant-derived flavonoids, in peach systems packed in retortable pouches. Neither A2P nor Pycnogenol significantly improved color or AA stability. Although significant statistical differences were observed in color variation, they were not so apparent visually. Next, we investigated the effects of fruit sources, calcium chloride, and alpha-glucosyl rutin (alpha-GR) on browning reactions. After storage at 40 degrees C for 270 days, pouches that were made of individually quick frozen (IQF) peaches and syrup with alpha-GR had a lower rate of browning and loss of AA than other treatments. Thus, alpha-GR is suggested to prevent color deterioration and improve shelf life of diced peaches. Novelty impact statement Color deterioration can limit shelf life of processed fruits. This study shows that alpha-glucosyl rutin successfully reduced color deterioration and loss of ascorbic acid in diced peaches in syrup packed in flexible retortable pouches. Therefore, the application of this water-soluble flavonoid is suggested to improve quality and shelf life of processed peach.

BACKGROUND: Listeria monocytogenes represents high risk for consumers, since it can grow under refrigeration and acidic environments by developing acid tolerance response (ATR).OBJECTIVE: The aim of this work was to study the growth and survival of ATR L. monocytogenes strain Scott A in media acidified with malic acid, lactic acid, or blueberry extract.METHODS: Bacterial growthwas evaluated using tryptic soy broth with yeast extract (TSB+ YE) combined with the different acid solutions and incubated at 25 degrees C for 24 h. An optical density system measured growth every 15 minutes for 24 h.RESULTS: Complete inhibition of L. monocytogenes occurred in presence of treatments including malic acid pH 2.0 and 3.0; lactic acid pH 2.0, 3.0, and 4.0; and with blueberry extract pH 2.0 in the mixture. No growth was observed in treatments under pH 4.5. Turbidity values of media mixed with blueberry extract at pH 3.0, 4.0, and 5.0 showed no statistical difference at 18 h and growth media had pH of 6.13, 6.53, and 6.78, respectively.CONCLUSIONS: Lactic acid was more effective inhibiting bacterial growth compared to malic acid. Blueberry extract was not effective acidifying the final pH of the TSB+ YE solutions, therefore L. monocytogenes survived in media acidified with low pH blueberry extract. Treatments with blueberry extract had the least antibacterial effect in this study.

This study addresses the development, dissemination, and assessment of a Food Safety System Management (FSSM) curriculum offered to college-aged, agribusiness students in Yerevan, Armenia. Prior to beginning the program, demographic data were collected and a paper-based pretest was administered to access the food safety knowledge, behavior, and attitude of participants (n = 29). For assessment of a skill, participants' handwashing techniques were videotaped and scored before the program commenced. Immediately after completion of the entire curriculum, a paper-based post-test with identical questions for food safety knowledge, behavior, and attitude was administered and handwashing skills were assessed. ANOVA with repeated measures was used to evaluate significant differences (alpha = 0.05) for food safety knowledge using a pretest, post-test, and a 3-mo follow-up. A paired t-test was used to evaluate handwashing skills before and after the curriculum was presented. The pretest score (44.93%, +/- 2.87) for food safety knowledge (n = 29) differed significantly (P < 0.0001) when compared with the post-test score (73.21%, +/- 3.28) and the 3-mo follow-up (n = 23) score (67.76%, +/- 3.93). Participants' (n = 9) handwashing skills prior to delivery of the FSSM curriculum differed significantly (P < 0.0001), when compared to handwashing skills after completion of the curriculum. Students' food safety attitudes and behavior assessed using a five-point Likert scale, also improved significantly as a result of the FSSM program. The 3-mo follow-up survey on food safety attitude and behavior was consistent with the post-test survey results. The information from this project may be of interest to education experts, Extension professionals, food industry personnel, or regulatory agencies, in the development and dissemination of an international food safety program.

The purpose of this study was to determine how commercial and designed packaging performed in the conditions of a retail dairy case with fluorescent and light-emitting diode (LED) lighting. Commercial retail cases in the Tennessee and Virginia area and the retail case used in this study were tested for light intensity (lux) within various locations on the shelf units with a hand-held light meter. Freshly processed milk (2%) was filled in high-density polyethylene (HDPE) packages with varying light protective additives (LPA). Treatments included yellow, low titanium dioxide (TiO2; 1.3%) and high (4.9%) TiO2; controls included translucent HDPE (0% TiO2; light exposed [LE]) and translucent HDPE with foil overwrap (light protected [LP]). All packages were stored for 4, 8, 16, 24, 48, and 72 h under fluorescent and LED light. Riboflavin (Rb) retention and thiobarbituric reactive substances (TBARS) were measured (2 replications) as indicators of initiation and secondary oxidation products. Means were compared using ANOVA and Tukey's HSD (α = 0.05). The polymer conducting electronic nose (eNose) analyzed headspace volatiles for milk quality for all packages under light treatments for 8 and 24 h (canonical distribution α = 0.05) for one replication. Commercial retail cases varied from 50 to 4,700 lux, with fluorescent light having a greater variability than LED lights. The retail case used in this study fell within the light intensity range of commercial retail cases. Mean light intensity within fluorescent (1,617 ± 505 lux) and LED (929 ± 97 lux) cases were significantly different, but this difference did not affect Rb and TBARS analysis based on analysis of covariance. Light protected performed most effectively under both lights whereas LE provided inadequate protection (P < 0.05). Milk in yellow and high TiO2 packages retained the highest concentration of Rb (61 and 55% retention, respectively) among LPA packages under LED through 72 h. Under fluorescent light, interactions with package and light were different from LED, suggesting light spectra and light transmittance interactions occur between light source and LPA packaging. Milk stored in the two lighting conditions each had unique volatile chemistry based on (eNose) canonical distribution. Under fluorescent light, eNose effectively separated controls from LPA packages but not under LED light, suggesting that LED does not have as much effect on volatile profile as does fluorescent light. High-density polyethylene packaging with pigments performs better under LED lights than under fluorescent lights at low lux conditions. Effective packaging should protect milk quality regardless of light and intensity.

A recent shift to more energy efficient light-emitting diode (LED) lights in retail dairy cases has occurred, but the effects of LED light on fluid milk in retail conditions are not known. Our objective was to determine the efficacy of polyethylene terephthalate (PET) packaging at preventing light-induced oxidation in 2% milk under LED and fluorescent retail light. Light interference effects were studied in combination with the oxygen barrier effects of PET. The extent of oxidation in 2% milk packaged in PET bottles (2 L; average wall thickness: 0.33 mm; treatments: clear with UV barrier and 2.1, 4.0, and 6.6% titanium dioxide [TiO2]) under fluorescent and LED retail light up to 72 h was studied. Two control packages (clear PET = full light exposure and PET wrapped with foil and plastic = no light exposure) were used for comparison, creating a total of six packaging experimental treatments. Chemical measures of oxidation (α = 0.05; ANOVA) included formation of secondary lipid oxidation products, riboflavin degradation, and headspace volatiles analysis by an electronic nose. Volatile analysis compared electronic nose smell-prints by canonical discrimination analysis. Sensory evaluation of milk (triangle test, 3 replications) compared milk from experimental packages to light-protected control milk for similarity (β = 0.05) and to light-exposed control milk for differences (α = 0.05). Polyethylene terephthalate with 6.6% TiO2 was an effective package for protecting fluid milk sensory quality for up to 8 h under LED light (936 ± 136 lux) but only for 4 h under fluorescent light (1,447 ± 1,072 lux). Polyethylene terephthalate with 4% or less TiO2 could not effectively protect milk flavor from light-induced changes through 4 h fluorescent or LED light exposure. Milk stored in PET packages retained 0.90 mg/L or higher riboflavin content over 72 h retail light exposure. Electronic nose technology differentiated (P < 0.05) volatile profiles among fresh milk with no light exposure and milk that remained under retail lights for 8 h or more, indirectly supporting the changes in sensory quality. The results conclude that LED light is less detrimental to milk quality than fluorescent light and higher levels of TiO2 in PET packages were more effective at preventing light-induced oxidation in 2% milk.

Five different packaging treatments were studied over a 36-day period to determine if they protected soymilk from photo-oxidation. Soymilk was packaged in high-density polyethylene (HDPE) bottles with and without light protective additives (LPA). Two controls [(1) no LPA (translucent appearance); (2) a light-protected control (foil overwrap over no LPA control)] and three LPA-containing treatments, Low (0.6% TiO2), Medium (1.3% TiO2), High (4.3% TiO2) were studied. Bottles were stored in a lighted refrigerated display case (average light intensity between 800 to 2200 lux; 3°C) for 36 days and evaluated weekly. Soymilk packaged in high LPA bottles was protected from developing light-oxidized off-flavors and odors for a minimum of 15 days. High LPA bottles provided protection for riboflavin and controlled development of photooxidative products for approximately 29 days.

Fresh blueberries are commonly stored and transported by refrigeration in controlled atmospheres to protect shelf life for long periods of storage. Ozone is an antimicrobial gas that can extend shelf life and protect fruit from microbial contamination. Shelf life of fresh highbush blueberries was determined over 10-day storage in isolated cabinets at 4°C or 12°C under different atmosphere conditions, including air (control); 5% O2 : 15% CO2 : 80% N2(controlled atmosphere storage (CAS)); and ozone gas (O3) 4 ppm at 4°C or 2.5 ppm at 12°C, at high relative humidity (90–95%). Samples were evaluated for yeast and molds growth, weight loss, and firmness. CAS and O3did not delay or inhibit yeast and molds growth in blueberries after 10 days at both temperatures. Fruit stored at 4°C showed lower weight loss values compared with 12°C. Blueberries stored under O3atmosphere showed reduced weight loss at 12°C by day 10 and loss of firmness when compared to the other treatments. Low concentrations of ozone gas together with proper refrigeration temperature can help protect fresh blueberries quality during storage.

Listeria monocytogenes is a foodborne pathogen that represents a high risk for consumers because it can grow under refrigeration conditions and can also develop acid tolerance. Fresh blueberries are hand-picked, packed, and transported under refrigeration without receiving a microbial inactivation treatment. The aim of this work was to study the survival of L. monocytogenes in fresh highbush blueberries stored at 4 or 12 °C under different controlled atmosphere conditions, including air (control); 5% O2, 15% CO2, 80% N2 (controlled atmosphere storage [CAS]); or ozone gas (O3), 4 ppm at 4 °C or 2.5 ppm at 12 °C, at high relative humidity (90 to 95%) for a total of 10 days. Fresh blueberries inside a plastic clamshell were spot inoculated with the bacteria and were stored at 4 or 12 °C in isolated cabinets under air, CAS, and O3 atmospheric conditions. Samples were evaluated on days 0, 1, 4, 7, and 10 for microbial growth using modified Oxford agar. CAS did not delay or inhibit L. monocytogenes growth in fresh blueberries after 10 days. O3 achieved 3- and 2-log reductions when compared with air treatment at 4 and 12 °C, respectively. Low concentrations of O3 together with proper refrigeration temperature can ensure product safety throughout transportation. O3 is a strong antimicrobial that safely decomposes to oxygen and water without leaving residues and can be used as an alternative method to prevent bacterial growth during a long transport period.

Long-duration space missions require the development of improved foods and novel packages that do not represent a significant disposal issue. In addition, it would also be desirable if rapid heating technologies could be used on Earth as well, to improve food quality during a sterilization process. For this purpose, a package equipped with electrodes was developed that will enable rapid reheating of contents via ohmic heating to serving temperature during space vehicle transit. Further, the package is designed with a resealing feature, which enables the package, once used, to contain and sterilize waste, including human waste for storage prior to jettison during a long-duration mission. Ohmic heating is a technology that has been investigated on and off for over a century. Literature indicates that foods processed by ohmic heating are of superior quality to their conventionally processed counterparts. This is due to the speed and uniformity of ohmic heating, which minimizes exposure of sensitive materials to high temperatures. In principle, the material may be heated rapidly to sterilization conditions, cooled rapidly, and stored. The ohmic heating device herein is incorporated within a package. While this by itself is not novel, a reusable feature also was developed with the intent that waste may be stored and re-sterilized within the packages. These would then serve a useful function after their use in food processing and storage. The enclosure should be designed to minimize mass (and for NASA's purposes, Equivalent System Mass, or ESM), while enabling the sterilization function. It should also be electrically insulating. For this reason, Ultem high-strength, machinable electrical insulator was used.

ABSTRACTPostprocessing contamination of the products in a processing plant has been identified as one of the major reasons for food contamination with Listeria; brining is one such postprocessing area. Our previous study has shown that the combinations of UV and antimicrobials reduces the number of this organism significantly in fresh brine, but brine is usually recycled from days to weeks depending on its use. Therefore, this study is focused on the reduction of L. monocytogenes in recycled chill brine (obtained from a frankfurter processor) using the combinations of UV and antimicrobial agents, such as citric acid (CA), hydrogen peroxide (HP) and dimethyl dicarbonate (DMDC). Results show that the combinations of UV and 2000 ppm and 4000 ppm HP were the most effective treatments in reducing the Listeria population with the total processing time of 120 min. Both of these treatments were found to be more effective than UV or HP alone. Additionally, all other treatments, such as the combinations of UV and CA (0.2 and 0.5%) and UV and DMDC (250 and 500 ppm) were comparatively less effective. This may be due to the presence of organic matter in spent brine, which may have reduced the penetration of UV and availability of antimicrobials for microbial interaction.PRACTICAL APPLICATIONSThe brine solutions are generally recycled in industries for up to 4 weeks as per United States Department of Agriculture (USDA) guide. Thus, it is very important to study various treatments to process recycled brine that was used to process ready‐to‐eat (RTE) meat products to prevent foodborne diseases or outbreaks. The use of UV light and antimicrobial agents to control L. monocytogenes in recycled brines to product cooling in the RTE meat industry is described. The study provides information on exposure time to UV light and level of antimicrobial agent that result in inactivation of the pathogen. Industry may benefit from our research in their validation efforts to control L. monocytogenes for recycled brine in recirculating chill brine systems through the use of UV light and antimicrobial agents.

Chill brine used during ready-to-eat meat processing is an important source of post-processing contamination by Listeria monocytogenes. The efficacy of UV in combination with citric acid (CA; 0.2 and 0.5%), dimethyl dicarbonate (DMDC; 250 and 500 ppm) or hydrogen peroxide (2,000 and 4,000 ppm) was determined to reduce L. monocytogenes in chill brine to below detectable levels after enrichment. Fresh brine solution was inoculated with L. monocytogenes and exposed to UV and/or antimicrobial agent at - 1C in a recirculating UV treatment unit. When L. monocytogenes was no longer detectable via direct plating on MOX, enrichment in brain-heart infusion broth was performed, and suspect colonies were confirmed using API Listeria. The combinations of UV + 0.5% CA and UV + 500-ppm DMDC were found to be the most effective, where L. monocytogenes was undetectable via enrichment at 45 and 60 min of treatment, respectively. CA (0.5%) when used in the absence of UV resulted in nondetection of L. monocytogenes. However, the reduction rate was higher when UV was used concurrent with CA. This work indicates that combinations of UV and antimicrobials may be more effective than either of the treatments alone for the reduction of L. monocytogenes in fresh brines.

Ultra high temperature treated milk (2%), exposed for 7 h at 10 degrees C to light of 200-400, 395, 463, 516, 567, 610 nm, or full light, was tested for volatile and odor-active compounds using gas chromatography and gas chromatography olfactometry. Exposure to ultraviolet wavelengths (200-400 and 395 nm) and full light produced the highest concentrations of volatile compounds. Exposure to 610 nm produced pentanal and an unidentified compound in high concentrations. Aroma-active compounds produced upon exposure to 516, 567, or 610 nm had relatively short retention times and low aroma intensities. Aroma-active compounds produced upon exposure to 200-400, 395, or 463 nm had relatively long retention times and slight to medium aroma intensities. (c) 2010 Published by Elsevier Ltd.

ABSTRACT The effects of packaging treatments, postharvest cooling delay and storage duration on color, texture, ascorbic acid content, weight loss and glucosinolate retention in crown‐cut heads of broccoli were studied. Broccoli stored in shrink wrap film lost 3.7% of its original weight, whereas ice packaging resulted in 17.4% weight loss during storage. Long postharvest cooling delay and storage duration negatively affected broccoli color. Broccoli heads stored in shrink wrap packaging retained firmness longer than broccoli stored in ice. Ascorbic acid retention was improved in shrink wrapped broccoli, but retention decreased as postharvest cooling delay and storage duration lengthened. Shrink wrapped broccoli exhibited improved retention of the glucosinolate, glucoraphanin. During storage, “Gypsy” broccoli maintained better quality than “Everest” with respect to color, ascorbic acid retention and weight loss. However, “Everest” retained texture (firmness) better after 35 days of storage. Shrink wrap packaging and shorter postharvest cooling delays preserve broccoli quality and increase shelf life. PRACTICAL APPLICATIONSBroccoli has the potential to be a high value crop if the shrink wrap packaging technology can be disseminated to the broccoli growers. Typically, farmers use ice for cooling broccoli heads after harvest, which is an expensive and difficult practice. Without icing requirement, broccoli marketing will be easy and opens up significant potential for broccoli producers who can afford relatively inexpensive film wrapping machines (as compared with ice equipment) in conjunction with onsite cooling. Sometimes onsite cooling is not possible and delays may be involved before the harvested produce is cooled. The conclusions reached in this study shows that shrink wrap packaging can be used to improve quality, retain phytochemical content and prolong the shelf life of crown‐cut broccoli.

Natural antioxidant additives were compounded into linear low-density polyethylene (LLDPE) using a twin-screw counter-rotating mixer and compression molded into films. Manufactured LLDPE films contained 2715 mg kg−1 α-tocopherol in its free and β-cyclodextrin complexed form and 1950 mg kg−1 quercetin in its free and γ-cyclodextrin complexed form. Both cyclodextrin complexes were loaded into films at 1.5% by weight. These natural antioxidants were incorporated into LLDPE resins with two different catalyst types, Ziegler-Natta and metallocene. Films were characterized by optical microscopy, oxidation induction time (OIT), oxygen transmission rate, contact angle analysis, and atomic force microscopy (AFM). All antioxidant additives increased the oxidative stability of LLDPE as measured by increased OIT, particularly quercetin. Natural antioxidants and their cyclodextrin inclusion complexes may provide a dual function in packaging to protect the polymer from oxidative degradation during melt processing and to delay the onset of oxidation of the packaged food during storage. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Sodium benzoate has been shown to produce benzene in combination with ascorbic acid. This has led to research for safe alternatives from plant essential oils and parabens that have shown some antimicrobial activity, but many of these compounds exhibit poor solubility in aqueous solutions. Cyclodextrins can increase the solubility of many compounds. This work aimed to investigate the solubility of 23 plant essential oils and 4 parabens in water and an apple juice medium. Four of these compounds were chosen for their low aqueous solubility to determine if complexing the compound with α- and β-cyclodextrin would increase solubility. Three of the complexes were dissolved in an acidified aqueous solution and then studied in glass and polyethylene terephthalate (PET) to determine if storage material would affect the stability. Solubility of the 27 compounds in distilled water ranged from 1.6 mg/L to 2460.6 mg/L and the solubility of 18 of the compounds decreased from 2.5 to 84.7% in apple juice medium (pH = 3.4, 12-13 °Brix). Complexation with cyclodextrin dramatically increased the solubility of the compounds, up to 10-fold. Packaging material had no effect on concentration of compounds present over 7 days. Cyclodextrins were able to increase solubility of these compounds to more suitable concentrations, and may lead to viable natural alternatives to sodium benzoate.

Polymer additive migration into a food product is dependent upon numerous factors including the original concentration of the additive in the polymer, its solubility in the food, its diffusion coefficient in the polymer, its partition coefficient between the polymer and food, temperature, and time. The limited solubility of quercetin in linear low-density polyethylene (LLDPE) did not allow release from the film due to phase segregation of the quercetin in the bulk polymer. Increasing the molecular weight of -tocopherol by -cyclodextrin inclusion complexation can greatly reduce its diffusion coefficient in LLDPE. Ziegler-Natta and metallocene LLDPE contain different crystalline structure morphologies and diffusion path networking arrangements that allow for differences in additive release rates. Effective controlled-release packaging should combine -cyclodextrin complexation of additives and polymer morphology control to target delivery of an optimal antioxidant concentration to achieve prolonged activity, resulting in extended shelf life foods.

Milk packaged in glass bottles overwrapped with iridescent films (treatments blocked either a single visible riboflavin [Rb] excitation wavelength or all visible Rb excitation wavelengths; all treatments blocked UV Rb excitation wavelengths) was exposed to fluorescent lighting at 4 degrees C for up to 21 d and evaluated for light-oxidized flavor. Controls consisted of bottles with no overwrap (light-exposed treatment; represents the light barrier properties of the glass packaging) and bottles overwrapped with aluminum foil (light-protected treatment). A balanced incomplete block multi-sample difference test, using a ranking system and a trained panel, was used for evaluation of light oxidation flavor intensity. Volatiles were evaluated by gas chromatography and Rb degradation was evaluated by fluorescence spectroscopy. Packaging overwraps limited production of light oxidation flavor over time but not to the same degree as the complete light block. Blocking all visible and UV Rb excitation wavelengths reduced light oxidation flavor better than blocking only a single visible excitation wavelength plus all UV excitation wavelengths. Rb degraded over time in all treatments except the light-protected control treatment and only minor differences in the amount of degradation among treatments was observed. Hexanal production was significantly higher in the light-exposed control treatment compared to the light-protected control treatment from day 7; it was only sporadically significantly higher in the 570 nm and 400 nm block treatments. Pentanal, heptanal, and an unidentified volatile compound also increased in concentration over time, but there were no significant differences in concentration among the packaging overwrap treatments for these compounds.

Cyclodextrin (CD) complexation procedures are relatively simple processes, but these techniques often require very specific conditions for each individual guest molecule. Variations of the coprecipitation from aqueous solution technique were optimized for the CD complexation of the natural antioxidants alpha-tocopherol and quercetin. Solid inclusion complex products of alpha-tocopherol/beta-CD and quercetin/gamma-CD had molar ratios of 1.7:1, which were equivalent to 18.1% (w/w) alpha-tocopherol and 13.0% (w/w) quercetin. The molar reactant ratios of CD/antioxidant were optimized at 8:1 to improve the yield of complexation. The product yields of alpha-tocopherol/beta-CD and quercetin/gamma-CD complexes from their individual reactants were calculated as 24 and 21% (w/w), respectively. ATR/FT-IR, 13C CP/MAS NMR, TGA, and DSC provided evidence of antioxidant interaction with CD at the molecular level, which indicated true CD inclusion complexation in the solid state. Natural antioxidant/CD inclusion complexes may serve as novel additives in controlled-release active packaging to extend the oxidative stability of foods.

The effect of high pressure processing in conjunction with the chemical antimicrobials, dimethyl dicarbonate (DMDC), hydrogen peroxide, cinnamic acid, potassium sorbate, and sodium benzoate (NaB) on E. coli O157:H7 strain E009 and Salmonella enterica serovar Agona was investigated in apple juice and orange juice, respectively. Juices were inoculated with approximately 10(6) CFU/ml and subjected to pressures of 550 MPa (E. coli O157:H7 samples) and 400 MPa (Salmonella Agona samples) for 2 min at 6 degrees C (initial temperature). Populations of each pathogen were determined before pressurization, immediately after pressurization, and after samples had been held after treatment for 24 h at 4 degrees C. The most effective treatment for E. coli O157:H7, as determined by plating immediately after pressurization, was 125 ppm of DMDC, which caused a >4.98-log reduction. Other treatments that were significantly different from the sample with no added antimicrobial were 62.5 ppm of DMDC, 300 ppm of hydrogen peroxide, and 500 ppm of NaB, which produced 4.97-, 5.79-, and 3.91-log total reductions, respectively. After 24 h at 4 degrees C, E. coli O157:H7 was undetectable in all treatment groups (and controls). In samples inoculated with Salmonella, the most effective treatment was 62.5 ppm of DMDC, which produced a 5.96-log decrease immediately after pressure treatment. The results for 1,000 ppm of NaB, which produced a 3.26-log decrease, also were significantly different from those for the sample containing no antimicrobials. After 24 h at 4 degrees C, all samples with added antimicrobials had near or more than a 5-log total reduction of Salmonella Agona.