Aubrey Mendonca

Iowa State University | ISU · Department of Food Science and Human Nutrition

Pathogens that adapt to environmental stress can develop an increased tolerance to some physical or chemical antimicrobial treatments. The main objective of this study was to determine if acid adaptation increased the tolerance of Escherichia coli O157:H7 to high voltage atmospheric cold plasma (HVACP) in raw pineapple juice. Samples (10 mL) of jui...

Pathogens that adapt to environmental stress can develop an increased tolerance to some physical or chemical antimicrobial treatments. The main objective of this study was to determine if acid adaptation increased the tolerance of Escherichia coli O157:H7 to high voltage atmospheric cold plasma (HVACP) in raw pineapple juice. Samples (10 ml) of jui...

The main objective of the present study was to determine the efficacy of dielectric barrier discharge (DBD) high voltage atmospheric cold plasma (HVACP) at 70 kV for inactivating Salmonella enterica and shiga-toxin-producing Escherichia coli (STEC) on desiccated shredded coconut. Additional objectives were to evaluate sub-lethal injury in pathogen...

As essential oils (EOs) possess GRAS status, there is a strong interest in their application to food preservation. Trends in the food industry suggest consumers are drawn to environmentally friendly alternatives, and less synthetic chemical preservatives. Although use of EOs has increased over the years, adverse effects have limited their use. This...

The antibacterial effect of oregano oil and tannic acid (TA) on the aerobic plate count (APC), Enterobacteriaceae (ENT), Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica in raw ground chicken breast meat (RGCBM) held at 4 °C and 10 °C was studied. Five treatments including i) control (no antimicrobial), ii) 200 ppm oregano...

Reformulation of food products with natural antimicrobials is a potential solution for several food-related problems: the growing consumers' request for natural products, the negative health impact due to the presence in foods of artificial antimicrobials, and the risk of emergence of new antimicrobial resistant pathogens. The assessment of minimum...

Reformulation of food products with natural antimicrobials is a potential solution for several food-related problems: the growing consumers’ request for natural products, the negative health impact due to the presence in foods of artificial antimicrobials, and the risk of emergence of new antimicrobial resistant pathogens. The assessment of minimum...

The effect of oregano oil and tannic acid (TA) on the aerobic plate count, Staphylococcus aureus growth, and staphylococcal enterotoxin A (SEA) production in cooked chicken breast meat held at abusive temperatures were evaluated. Five treatments, namely, control, 200 ppm oregano essential oil, 10 ppm TA, 200 ppm oregano oil + 10 ppm TA, and 5 ppm b...

Enteric pathogens such as Salmonella enterica can survive in low pH conditions and pose a food safety threat during marinating of raw poultry meat. A study was conducted to investigate the effectiveness of thyme oil for killing S. enterica on raw chicken during marination in lemon juice containing yucca extract. Samples of raw chicken breast were i...

The extent of chlorine inactivation and sublethal injury of stationary-phase (STAT) and long-term survival-phase (LTS) cells of Shiga toxin-producing Escherichia coli (STEC) in vitro and in a lettuce postharvest wash model was investigated. Four STEC strains were cultured in tryptic soy broth supplemented with 0.6% (w/v) yeast extract (TSBYE; 35°C)...

Cold plasma technology is an advanced oxidation process (AOP), which has shown significant potential for pesticide degradation. The aim of this study was to determine the degradation efficacy and transformation products for cold plasma treated carbamates in water. The dissipation of three carbamates, namely, carbaryl, methiocarb and aminocarb were...

Frankfurters formulated with or without sodium lactate [SL; 2% (w/w)] and surface-treated by with lactic acid [LA; 0 and 5% (v/v)] and sodium lauryl sulfate [SLS; 0, 0.5 and 1% (w/v)] alone or combined, were evaluated as an USDA-FSIS Alternative 1 post-lethality intervention against Listeria monocytogenes (LM). Post-peeling dipping of frankfurtersi...

Atmospheric cold plasma (ACP) is a promising non-thermal technology for controlling food spoilage. In this study, ACP treatment at 100 kV for 1, 3 and 5 min was applied to chicken breast samples. Approximately 2 log CFU/g reduction in natural microflora of chicken was achieved within 5 min of treatment and 24 h of storage. The observed reduction wa...

This chapter examines the microbiological considerations for the production, domestic sale and export of a wide range of food products from developing countries in a wide range of categories. It provides an overview of microorganisms of concern for food safety and product quality in meats, seafood, poultry, dairy products, beverages, prepared foods...

Two novel biosurfactants – surfactin and its variant fatty acyl glutamic acid (FA-glu) – were compared with two commercial emulsifiers – lecithin, and a mixture of Tween 80 and lauric „arginate (TLA) – for formation and stability of emulsions and nano„emulsions containing cinnamaldehyde (CM). The nano„emulsions’/emulsions’ antimicrobial performance...

Abstract The antimicrobial effectiveness of isoeugenol against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in refrigerated (4 °C) pineapple juice (PJ) with added 0.5% (w/v) yucca extract (YEX) was investigated. Sub-lethal injury of pathogen survivors and sensory characteristics of PJ were also evaluated. Samples of PJ...

Bacterial foodborne disease outbreaks implicating raw wheat products have focused much attention on decontaminating wheat grains used for manufacturing flour and other milled products. The present study investigated the effectiveness of atmospheric cold plasma (ACP) for destroying Shiga-toxin-producing Escherichia coli, Salmonella enterica and natu...

The effectiveness of selected antimicrobial solutions for killing Salmonella enterica and Escherichia coli O157:H7 on artificially inoculated parsley and green onions has been tested. Samples (25 g) of green onions and parsley were artificially inoculated with a 5 strain-cocktail of each pathogen and held at 23 ± 1 °C (16 to 18 hours) before immers...

Shelf-life is defined as the time a food product retains its desired sensory, chemical, and physical characteristics while also remaining safe for consumption. Bacteria associated with meat spoilage produce off-odors and flavors, tissue discoloration, gas, and slime. The objectives of this study were, 1) to determine the effect of refrigerated-disp...

Nonendospore-forming pathogenic bacteria in the long-term survival (LTS) phase can remain viable for months or years and may show reduced susceptibility to various antimicrobial interventions. In the present study, we investigated the response of LTS phase Salmonella enterica serovar Typhimurium (ATCC 14028) to ultraviolet (UV) radiation in 0.85% (...

The standard plate count is one of the most common of the microbiological methods used to assess the overall quality of foods. The major drawbacks of this method are that it is time consuming, labor intensive, and expensive when a large number of samples are to be analyzed. Moreover, it is of little value to food processors when total microbial cou...

The growing interest in using plant-derived extracts, including essential oils (EOs), as natural antimicrobials in foods is fueled by the need to reduce the use of synthetic food additives. In recent years, research on applications of EOs and their components in various food groups has intensified. Optimal food applications of EOs are limited by fa...

In this chapter, methods of meat preservation that discourage microbial growth through the creation of unfavorable environments in the meat are considered. These involve action more directly inhibitory or lethal to molds and bacteria. This chapter discusses the principles, physical and biochemical aspects, antimicrobial aspects, quality aspects, an...

The antioxidant effects of oregano essential oil and tannic acid combinations on ground chicken breast and thigh meats were studied. Six treatments, including: 1) control (none added), 2) 100 ppm oregano essential oil + 5 ppm tannic acid, 3) 100 ppm oregano essential oil + 10 ppm tannic acid, 4) 200 ppm oregano essential oil + 5 ppm tannic acid, 5)...

In this chapter, methods of meat preservation that discourage microbial growth through the creation of unfavorable environments in the meat are considered. These involve action more directly inhibitory or lethal to molds and bacteria. This chapter discusses the principles, physical and biochemical aspects, antimicrobial aspects, quality aspects, an...

The effectiveness of cinnamaldehyde for inactivating Salmonella enterica and Escherichia coli O157:H7 in carrot juice (CRJ) and mixed berry juice (MBJ) was investigated. Brain heart infusion broth (BHI), CRJ, and MBJ, with concentrations of added cinnamaldehyde ranging from 0.15 to 1.5 μL/mL, 0.25 to 2.0 μL/mL, and 0.25 to 1.5 μL/mL, respectively,...

Our research objective was to evaluate the ability of produce washes to maintain the texture and color quality attributes of watermelon and cantaloupe while reducing the levels of natural fungi population on the melon surface. Melons were submerged for 2 min into either water control or water containing quaternary ammonium chloride (300 ppm) or an...

The objective of this study was to determine the effect of tannic acid (TA) on the oxidative stability and the quality characteristics of ground chicken breast meat. Five treatments including (1) control (none added), (2) 2.5 ppm TA, (3) 5 ppm TA, (4) 10 ppm TA, and (5) 5 ppm butylated hydroxyanisole (BHA) were added to boneless, skinless ground ch...

A study was conducted to investigate the effect of oregano essential oil on the oxidative stability and color of raw and cooked chicken breast meats. Five treatments, including (1) control (none added); (2) 100 ppm oregano essential oil; (3) 300 ppm oregano essential oil; (4) 400 ppm oregano essential oil; and (5) 5 ppm butylated hydroxyanisole (BH...

Over the past few years, foodborne disease outbreaks linked to enteric pathogens present on cantaloupe and watermelon surfaces have raised concerns in the melon industry. This research evaluated the effectiveness of commercially available produce sanitizers against selected foodborne pathogens, both in cell suspensions and on the outer rind surface...

The growing demand and expectations of health conscious consumers for foods that are safe, nutritious, fresh-like, and synthetic preservative-free, are major drivers of technological change and innovation in the food industry. In past decades, food manufacturers enjoyed abundant sales of their products while presenting erroneous or deceptive food l...

Hazard Analysis Critical Control Points (HACCP) is a systematic approach to food safety education for the food industry. To receive a HACCP certificate, participants must receive an 80% or higher on the final examination. Language barriers, educational levels, and age have been noted as primary reasoning's for not passing the final examination. Cli...

Strawberries are soft fruit that are not recommended to have a post-harvest wash due to quality concerns. Escherichia coli O157:H7 has been linked to outbreaks with strawberries but little is known about the survival of E. coli during the growth cycle of strawberries. The survival of E. coli on strawberry plants during growing under greenhouses con...

Abstract This study evaluated the influence of starvation on the radiation resistance and injury in Escherichia coli O157:H7, following electron beam irradiation in 0.85% (wt/vol) saline and in apple juice. Washed exponential-phase cells of E. coli O157:H7 that were grown in tryptic soy broth (TSB) at 35°C were starved in 0.85% saline (25°C) for 10...

The objective of this study was to investigate natural antimicrobials including cranberry powder, dried vinegar and lemon juice/vinegar concentrate, and post-lethality interventions (lauric arginate, octanoic acid, thermal treatment and high hydrostatic pressure) for the control of Listeria monocytogenes on alternatively-cured frankfurters. Lauric...

Abstract Ready-to-eat (RTE) meat and poultry products manufactured with natural or organic methods are at greater risk for Listeria monocytogenes growth, if contaminated, than their conventional counterparts due to the required absence of preservatives and antimicrobials. Thus, the objective of this study was to investigate the use of commercially...

Sodium nitrite exerts an inhibitory effect on the growth of Listeria monocytogenes. The objective of this study was to investigate the effects of various nitrite concentrations from a vegetable source with and without high hydrostatic pressure (HHP) on the recovery and growth of L. monocytogenes on ready-to-eat restructured ham. A preconverted cele...

A sublethally injured bacterial cell has been defined as a cell that survives a stress such as heating, freezing, acid treatment, or other antimicrobial intervention but can repair the cellular damage exerted by the stressor and later regain its original ability to grow. Consequently, sublethally injured cells are not likely to be included in conve...

The standard plate count is one of the most common of the microbiological methods used to assess the overall quality of foods. The major drawbacks of this method are that it is time consuming, labor intensive, and expensive when a large number of samples are to be analyzed. Moreover, it is of little value to food processors when total microbial cou...

Types of irradiation with wavelengths of 2000 Å or less are highly energetic and generate ions as they pass through materials. Ionizing radiation typically is produced by Gamma radiators or electron accelerators and can kill microorganisms without increasing the temperature of irradiated material. Irradiation damages microbial cell components, incl...

With the knowledge that retail pork products may be contaminated with methicillin-resistant Staphylococcus aureus (MRSA), the risk of consumers contracting a MRSA infection or foodborne illness from processed meats, especially bacon, is uncertain. Therefore, a study was designed to investigate the survival of MRSA during heat treatment of slab baco...

Abstract Infections from antibiotic-resistant bacteria are a major concern for human health professionals around the world. Methicillin-resistant Staphylococcus aureus (MRSA) is just one of the resistant organisms of concern. MRSA prevalence has also been recently reported in retail meat products at rates higher than originally thought. Although th...

Campylobacter is one of the leading causes of human foodborne illnesses originating from meat and poultry products. Cross-contamination of this organism occurs in many poultry processing plants, and can occur in the kitchens and refrigerators of consumers. Therefore, new intervention strategies are needed for meat and poultry products to better pro...

This study was conducted to investigate the efficacy of controlling Listeria monocytogenes on frankfurters and cooked pork chops with irradiation and modified atmosphere packaging (MAP) containing a high concentration of CO(2). Frankfurters and cooked pork chops were inoculated with a five-strain cocktail of L. monocytogenes and packaged in vacuum...

The efficacy of controlling Escherichia coli O157:H7 in ground beef patties by combining irradiation with vacuum packaging or modified atmosphere packaging (MAP) was investigated. Fresh ground beef patties were inoculated with a five-strain cocktail of E. coli O157:H7 at 5 log CFU/g. Single patties, packaged with vacuum or high-CO(2) MAP (99.6% CO(...

The objective of this study was to determine the effect of nisin and selected meat additives (salt, lactate, lactate–diacetate combination, and polyphosphate) on the antimicrobial activities of ovotransferrin (OTF) against the growth of Listeria monocytogenes. A Bioscreen C turbidometer (Oy Growth Curves AB Ltd., Helsinki, Finland) was used to eval...

Salmonella is one of the leading causes of human foodborne illnesses originating from meat and poultry products. Cross-contamination of Salmonella from raw to cooked products continues to be problematic in the food industry. Therefore, new intervention strategies are needed for meat and poultry products. Vacuum or modified atmosphere packaging (MAP...

The antimicrobial effects of the natural flavonoids kaempferol, quercetin, apigenin, and naringenin as well as a novel flavonoid 7-O-butyl naringenin against the growth of four meat-born Staphylococcus aureus strains were evaluated. First, the flavonoids were screened for inhibitory effects against the growth of each strain using the paper disc dif...

Salt concentration, vegetable juice powder (VJP) concentration and temperature were investigated to determine necessary conditions for incubation of curing brines including VJP and a starter culture containing Staphylococcus carnosus prior to production of naturally cured, no-nitrate/nitrite-added meat products. Subsequently, incubated brines were...

Enterobacter sakazakii ATCC 12868 (ES) is a very dangerous opportunistic organism likely to contaminate post-pasteurised dry milk products with a high mortality rate (40-80%). This study evaluated the antimicrobial efficacy of probiotics against ES in reconstituted dried infant formula. Initial study at 30C showed that Enterococcus faecium M-74 (EF...

There is an increasing global trend towards the use of more environmentally friendly antimicrobials in the food industry. For the present study, tomatoes and Serrano peppers, inoculated with a 5-serotype mixture of S. enterica (7.0 log 10 CFU/tomato or pepper) were immersed (for 2.0 or 4.0 min) in water (control), chlorine (150 ppm), PRO-SAN, and P...

Flavonoids have biofunctional effects as antioxidant and antimicrobial agents. The objective of this study was to evaluate the bactericidal activity and antilipopolysaccharide (LPS) effects of flavonoids on Escherichia coli O157:H7. The effects of flavonoids on the growth of E. coli O157:H7 were bacteriostatic rather than bactericidal at concentrat...

Grape seed extract (GSE) is a rich source of proanthocyanidins, a class of natural antioxidants reported to have wide-ranging bioactivity as anti-inflammatory, anticarcinogenic, and antimicrobial agents. The ability of GSE to rapidly inactivate Listeria monocytogenes in vitro and the generally recognized as safe status of GSE make this extract an a...

Numerous epidemiological studies revealed that the catering units are the most frequent incriminated in food-borne outbreak cases, the food processed in these establishments being considered, in some cases, a real threat to public health. Investigation of the outbreaks underlined serious mistakes associated with the technology and the steps followe...

The aim of the present study was to evaluate bacterial transglutaminase effect on the gelification properties of the myofibrillar proteins concentrates obtained from mechanically deboned poultry meat, breast and legs. Bacterial transglutaminase determined the formation of intra- and intermolecular cross-links between myofibrillar proteins, improvin...

The effects of pressure (400, 500 and 600 MPa), dwell time (1 and 5 min) and temperature (25 and 75 degrees C) on microbial quality and protein stability of soymilk during 28 days of storage (4 degrees C) were evaluated under aerobic and anaerobic conditions. After processing and during storage, there were significant differences in total bacterial...

A Swiss cheese curd slurry model system was used as a preliminary screening method to determine the feasibility of the incorporation of probiotic bacteria (Bifidobacterium breve R0070, Bifidobacterium infantis R0033, Bifidobacterium longum R0175, and Pediococcus acidilactici R1001) into Swiss cheese. The cheese curd was inoculated with probiotic ba...

IntroductionSources of Microorganisms in Raw MeatEffect of Cooking on Microorganisms in MeatSources of Microorganisms in Cooked MeatsFactors Affecting Microbial Growth in Cooked MeatsMicrobial Spoilage of Cooked MeatsPerishable Cooked Uncured MeatsPerishable Cooked Cured MeatsShelf-Stable Canned Uncured Meat ProductsShelf-Stable Canned Cured Meat P...

The objective of this study was to determine the effect of antimicrobials on the survival and proliferation of Listeria monocytogenes in turkey breast rolls following electron-beam irradiation. Six antimicrobial additive treatments that include no preservatives (control), 0.1% potassium benzoate (PB), 2% sodium lactate (SL), 0.1% potassium benzoate...

The aim of this study was to evaluate the effect of EDTA, lysozyme, or the combination of EDTA and lysozyme on the antibacterial activity of ovotransferrin against Escherichia coli O157:H7. Ovotransferrin solutions (20 mg/mL) containing 100 mM NaHCO3 (OS) with added EDTA (2.0 or 2.5 mg/mL), lysozyme (1.0, 1.5, or 2.0 mg/mL), or both were prepared....

The influence of NaHCO(3) and citric acid on the antibacterial activity of apo-ovotransferrin in model systems and ham was investigated. The antibacterial activity of 20 mg/mL of ovotransferrin solution with added NaHCO(3) (0, 25, 50, or 100 mM) or citric acid (0.25 or 0.5%) was evaluated against Escherichia coli O157:H7 and Listeria monocytogenes...

The effect of electron beam irradiation on the survival and growth of Listeria monocytogenes and natural microflora in oven-roasted turkey breast rolls and turkey hams was evaluated. Slices of turkey breast rolls and hams were inoculated with a 5-strain mixture of L. monocytogenes to achieve 10(6) to 10(7) cfu/cm(2); vacuum-packaged; irradiated at...

This study evaluated the effect of EDTA and lysozyme on the antibacterial activities of activated ovotransferrin against 5 strains of Listeria monocytogenes. First, a disc test was performed to screen the concentrations of EDTA or lysozyme that showed antibacterial activities in ovotransferrin (O) or ovotransferrin in 100 mM NaHCO3 (OS) solution. T...

The effects of continuous high hydrostatic water pressure treatments (414 and 483 MPa with a holding time of 6 min) on the viability of two strains of Salmonella enterica serovar Enteritidis (PT 9c and PT 30) inoculated onto raw almonds were evaluated at 25 degrees C. The concentrations of both Salmonella Enteritidis isolates were reduced to undete...

Frankfurters were surfaced-inoculated with a 5-strain mixture of Listeria monocytogenes (3.40 or 5.20 log CFU/g) and vacuum-packaged (as one link, 5 links or 10 links per package) after treatments with 3,000 AU or 6,000 AU of pediocin (in ALTATM2341) per link. Treatments were evaluated for L. monocytogenes counts initially and during storage (4C, 1...

The effects of selected organic acids and salts on microbial numbers, pH, exudate, and color were studied for vacuum-packaged, fresh pork chops. Pork chops were dipped for 2 min in (v/v) 1% acetic acid, 1% acetic/1% lactic acid, 1.5% acetic/1.5% sodium acetate, 3% acetic/3% sodium ascorbate, 3% acetic/2% NaCl or sterile, distilled water before bein...

Microbiological and some physical and chemical effects of treating pork chop surfaces with sodium acid pyrophosphate, a commercial phosphate blend, potassium sorbate and phosphate/sorbate/sodium acetate solutions, with or without sodium chloride, before packaging were studied in pork chops vacuum-packaged and stored at 2–4°C for 10 weeks. All treat...

The technical feasibility of using organic acid salts for surface treatment of frankfurters to determine their sensory and other quality characteristics and their ability to inhibit bacterial growth was investigated. To be practically effective, such treatments for frankfurters should have no adverse effects on meat quality attributes, including se...

Meat is one of the major sources of pathogens that cause foodborne illness in humans. The intervention strategies for pathogens in meat can be divided into preharvest reduction of microorganisms in livestock and postharvest decontamination on carcass and meat. The reduction of bacteria in animal is achieved by priming their immune system via the us...