Publications by authors named "Philip G Crandall"

47 Publications

Further Evidence of How Unbuffered Starvation at 4°C Influences Listeria monocytogenes EGD-e, HCC23, F2365, and Scott A.

J Food Prot 2017 10;80(10):1749-1759

1 Department of Food Science and Center for Food Safety and.

The soilborne pathogen Listeria monocytogenes frequently contaminates food products and food processing environments and is able to survive desiccation, high osmotic pressures, and starvation. However, little is known about how this pathogen survives starvation at 4°C. This study provides evidence that L. monocytogenes is able to survive total nutrient starvation for 4 weeks. L. monocytogenes strains EGD-e, Scott A, F2365, and HCC23 were starved individually in sterile water. Colony counts declined over 4 weeks, with Scott A declining the most rapidly. Transmission electron microscopy images revealed degradation of starving cell membranes and altered cytosols. Starving cells were subjected to the metabolic inhibitors fluoride, arsenite, 2,4-dinitrophenol, iodoacetate, and cyanide individually. Iodoacetate, which inhibits glyceraldehyde-3-phosphate dehydrogenase, completely reduced cultivable counts below the level of detection compared with the control starving cells; 2,4-dinitrophenol, which dissipates proton motive force, almost completely reduced cultivable counts. These results suggest that L. monocytogenes strains EGD-e, Scott A, F2365, and HCC23 are actively using part of the glycolysis pathway while starving. These results suggest that starving L. monocytogenes cells retain aspects of active metabolism.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4315/0362-028X.JFP-17-041DOI Listing
October 2017

Impact of the Global Food Safety Initiative on Food Safety Worldwide: Statistical Analysis of a Survey of International Food Processors.

J Food Prot 2017 10;80(10):1613-1622

4 Diversey Consulting, Sealed Air, Paris, France.

In 2000, the Consumer Goods Forum established the Global Food Safety Initiative (GFSI) to increase the safety of the world's food supply and to harmonize food safety regulations worldwide. In 2013, a university research team in conjunction with Diversey Consulting (Sealed Air), the Consumer Goods Forum, and officers of GFSI solicited input from more than 15,000 GFSI-certified food producers worldwide to determine whether GFSI certification had lived up to these expectations. A total of 828 usable questionnaires were analyzed, representing about 2,300 food manufacturing facilities and food suppliers in 21 countries, mainly across Western Europe, Australia, New Zealand, and North America. Nearly 90% of these certified suppliers perceived GFSI as being beneficial for addressing their food safety concerns, and respondents were eight times more likely to repeat the certification process knowing what it entailed. Nearly three-quarters (74%) of these food manufacturers would choose to go through the certification process again even if certification were not required by one of their current retail customers. Important drivers for becoming GFSI certified included continuing to do business with an existing customer, starting to do business with new customer, reducing the number of third-party food safety audits, and continuing improvement of their food safety program. Although 50% or fewer respondents stated that they saw actual increases in sales, customers, suppliers, or employees, significantly more companies agreed than disagreed that there was an increase in these key performance indicators in the year following GFSI certification. A majority of respondents (81%) agreed that there was a substantial investment in staff time since certification, and 50% agreed there was a significant capital investment. This survey is the largest and most representative of global food manufacturers conducted to date.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4315/0362-028X.JFP-16-481DOI Listing
October 2017

The Potential Link between Thermal Resistance and Virulence in : A Review.

Front Vet Sci 2017 14;4:93. Epub 2017 Jun 14.

Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, United States.

In some animals, the typical body temperature can be higher than humans, for example, 42°C in poultry and 40°C in rabbits which can be a potential thermal stress challenge for pathogens. Even in animals with lower body temperatures, when infection occurs, the immune system may increase body temperature to reduce the chance of survival for pathogens. However, some pathogens can still easily overcome higher body temperatures and/or rise in body temperatures through expression of stress response mechanisms. is the causative agent of one of the most prevalent foodborne illnesses, salmonellosis, and can readily survive over a wide range of temperatures due to the efficient expression of the heat (thermal) stress response. Therefore, thermal resistance mechanisms can provide cross protection against other stresses including the non-specific host defenses found within the human body thus increasing pathogenic potential. Understanding the molecular mechanisms associated with thermal responses in is crucial in designing and developing more effective or new treatments for reducing and eliminating infection caused by that have survived heat stress. In this review, thermal resistance is assessed followed by an overview of the thermal stress responses with a focus on gene regulation by sigma factors, heat shock proteins, along with the corresponding thermosensors and their association with virulence expression including a focus on a potential link between heat resistance and potential for infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fvets.2017.00093DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5469892PMC
June 2017

Correction for Gibson et al., Removal and Transfer of Viruses on Food Contact Surfaces by Cleaning Cloths.

Appl Environ Microbiol 2017 02 1;83(4). Epub 2017 Feb 1.

University of Arkansas, Division of Agriculture, Department of Food Science, and Center for Food Safety, Fayetteville, Arkansas, USA.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.03373-16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5288822PMC
February 2017

Effects of smoking and marination on the sensory characteristics of cold-cut chicken breast filets: A pilot study.

Food Sci Biotechnol 2016 31;25(6):1619-1625. Epub 2016 Dec 31.

1Department of Food Science, University of Arkansas, Fayetteville, AR 72704 USA.

This study aimed to determine individual and combined effects of smoking and marination on the sensory characteristics of boneless, skinless chicken breast meat. Four types of cooked, cold-cut chicken breast meat, i.e., marinated cooked, marinated smoked, and controls of non-marinated cooked and non-marinated smoked chicken, were evaluated for 28 sensory characteristics. Marination significantly increased saltiness, sweetness, roasted flavor, smoked flavor, and moistness of the cold-cut chicken breast meat. In addition, smoking significantly enhanced the saltiness, bitterness, roasted flavor, smoked flavor, and moistness of mass. Interestingly, a combination of smoking and marination processes resulted in a synergistic increase in the perceived moistness of mass compared to their individual treatments. In conclusion, this study demonstrates individual and combined influences of smoking and marination on the sensory characteristics of cold-cut chicken breast meat.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10068-016-0249-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6049239PMC
December 2016

An observational study of handwashing compliance in a child care facility.

Am J Infect Control 2016 12;44(12):1469-1474

Department of Food Science, University of Arkansas, Fayetteville, AR.

Background: Handwashing (HW) compliance, although an effective means of limiting childhood illness, remains low among personnel in early childhood centers (ECCs). Our study determined HW compliance and efficacy of ECC personnel.

Methods: Surveillance cameras were used to determine HW opportunities, compliance, occurrences, and effectiveness based on child-care oriented criteria.

Results: We observed 349 HW triggering events, with 14 events per hour; a median of 2 personnel (caregivers, paraprofessional aides, or parents) were present at any given time period. Compliance was 30% (caregivers), 11% (paraprofessional aides), and 4% (parents), with an overall compliance of 22%. Between-room and between-age groups of children being cared for and compliance of caregivers and paraprofessional aides were not found to be significantly different (P < .05). For all personnel between the 10 different rooms, the median compliance was 20.2% (95% confidence interval, 8%-35%). Only 7% of personnel taking care of 2- to 3-year-old children washed their hands, the lowest compliance per age group. Of all steps in HW, paper towel usage had the highest compliance, with a 97% adherence, whereas turning off the faucet with a paper towel was the lowest at 17%.

Conclusions: Methods and strategies need to be developed to increase compliance. Current technology provides an effective means of gathering data for determining HW compliance in ECCs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ajic.2016.08.006DOI Listing
December 2016

Using Olfaction and Unpleasant Reminders to Reduce the Intention-behavior Gap in Hand Washing.

Sci Rep 2016 Jan 6;6:18890. Epub 2016 Jan 6.

Department of Food Science, University of Arkansas, Fayetteville, AR 72704.

Lack of hand washing is a leading cause of food borne illnesses. To successfully increase hand hygiene compliance, interventions must have continual engagement with employees. This study used a real-time prospective memory (PM) scenario to measure the effectiveness of a control and sensory reminders of disgust to influence hand washing behavior and performance. First, a model of hand washing performance was built by having six participants' hands contaminated with GermGlo (a florescent micro-particle) and then washed their hands using predetermined protocols while monitored by an electronic hand hygiene verification (HHV) system. Next, eighty Hispanic/Latino participants, in a between-group experimental design, performed a PM experiment while one of four reminders were present (hand washing poster, disgusting image, disgusting sound, and disgusting odor) as the HHV recorded their hand washing performance. Visual cues, typical of hand washing campaigns, were not as effective at increasing hand hygiene compliance as disgust-induced sensory cues. Furthermore, olfactory disgust showed a significantly higher probability that individuals would engage in hand washing behaviors than all other conditions. This study provides new insight into the effectiveness of different senses and emotion to reduce the intention-behavior gap associated with modifying behaviors, and broadens current PM research to a real-time application.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/srep18890DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4702082PMC
January 2016

Potential of Plant Essential Oils and Their Components in Animal Agriculture - in vitro Studies on Antibacterial Mode of Action.

Front Vet Sci 2015 14;2:35. Epub 2015 Sep 14.

Department of Food Science, Center for Food Safety, University of Arkansas , Fayetteville, AR , USA.

The antimicrobial activity of essential oils and their components has been recognized for several years. Essential oils are produced as secondary metabolites by many plants and can be distilled from all different portions of plants. The recent emergence of bacteria resistant to multiple antibiotics has spurred research into the use of essential oils as alternatives. Recent research has demonstrated that many of these essential oils have beneficial effects for livestock, including reduction of foodborne pathogens in these animals. Numerous studies have been made into the mode of action of essential oils, and the resulting elucidation of bacterial cell targets has contributed to new perspectives on countering antimicrobial resistance and pathogenicity of these bacteria. In this review, an overview of the current knowledge about the antibacterial mode of action of essential oils and their constituents is provided.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fvets.2015.00035DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4672195PMC
December 2015

The Elimination of Listeria Monocytogenes Attached to Stainless Steel or Aluminum Using Multiple Hurdles.

J Food Sci 2015 Jul 29;80(7):M1557-62. Epub 2015 May 29.

Authors Mertz, O'Bryan, Crandall, Ricke, and Morawicki are with Dept. of Food Science, Univ. of Arkansas, Fayetteville, AR, 72704, U.S.A.

Unlabelled: Ready-to-eat luncheon meats sliced in retail delis have been found to pose the greatest risk of foodborne illness from Listeria monocytogenes among all ready-to-eat foods. Slicers used in delis have many removable parts that are connected with seals and gaskets, with spaces, cracks and crevices that are difficult to clean adequately and may provide a niche for L. monocytogenes survival. Standard cleaning and sanitizing practices used by deli employees may not eliminate Listeria in these niches. Moist heat is known to be more effective against L. monocytogenes than dry heat at the same temperature and time. The study reported here investigated the effects of moist heat combined with quaternary ammonium compounds (5 or 10 ppm), chlorine (10 or 25 ppm) or peracetic acid (10 or 25 ppm) on inactivating L. monocytogenes attached to stainless steel or aluminum coupons cut from commercial deli meat slicer components. All sanitizers when used alone resulted in a 2- to 3-log reduction of L. monocytogenes on stainless steel or aluminum surfaces, while moist heat alone resulted in a 3- to 4-log reduction. When combined with heat the quaternary ammonium was used at 5 ppm, peracetic acid at 10 ppm and chlorine at 10 ppm. When the 2 lethal treatments were combined there was a 5- to7-log reduction as compared to initial inoculation.

Practical Application: The results of this study will provide a better understanding and potential methods for the sanitization of industrial deli meat slicers. In turn, the knowledge gained from this study can reduce the risk of contamination and outbreaks of L. monocytogenes and other food-borne pathogens for consumers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1750-3841.12926DOI Listing
July 2015

Sensory impact of chemical and natural antimicrobials on poultry products: a review.

Poult Sci 2015 Jul 25;94(7):1699-710. Epub 2015 May 25.

Department of Food Science, University of Arkansas, 2650 North Young Avenue, Fayetteville, AR 72704, U.S.A

Antimicrobial agents are added to poultry products after slaughter to prevent the growth of pathogenic and spoilage microorganisms and to extend the shelf-life of these products. Antimicrobials can be either natural or chemical, which may affect the sensory attributes at elevated concentrations, such as surface color, odor, flavor, taste, and texture of the poultry products. Thus, when selecting antimicrobials for use in poultry processing, it is vital to consider the antimicrobial-induced changes in sensory aspects from the consumers' perspectives. In spite of its importance, there has been no systematic review on the influences of antimicrobials on sensory aspects of poultry products. This paper reviews the major antimicrobial agents used in the poultry processing industry and their effects on sensory aspects of the poultry products.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3382/ps/pev134DOI Listing
July 2015

Sweetgum: An ancient source of beneficial compounds with modern benefits.

Pharmacogn Rev 2015 Jan-Jun;9(17):1-11

Sea Star International LLC, Fayetteville, Arkansas, USA ; Department of Food Science and Center for Food Safety, University of Arkansas, Fayetteville, Arkansas, USA.

Sweetgum trees are large, deciduous trees found in Asia and North America. Sweetgum trees are important resources for medicinal and other beneficial compounds. Many of the medicinal properties of sweetgum are derived from the resinous sap that exudes when the outer bark of the tree has been damaged. The sap, known as storax, has been used for centuries to treat common ailments such as skin problems, coughs, and ulcers. More recently, storax has proven to be a strong antimicrobial agent even against multidrug resistant bacteria such as methicillin-resistant Staphylococcus aureus. In addition to the sap, the leaves, bark, and seeds of sweetgum also possess beneficial compounds such as shikimic acid, a precursor to the production of oseltamivir phosphate, the active ingredient in Tamiflu®-an antiviral drug effective against several influenza viruses. Other extracts derived from sweetgum trees have shown potential as antioxidants, anti-inflammatory agents, and chemopreventive agents. The compounds found in the extracts derived from sweetgum sap suppress hypertension in mice. Extracts from sweetgum seeds have anticonvulsant effects, which may make them suitable in the treatment of epilepsy. In addition to the potential medicinal uses of sweetgum extracts, the extracts of the sap possess antifungal activity against various phytopathogenic fungi and have been effective treatments for reducing nematodes and the yellow mosquito, Aedes aegypti, populations thus highlighting the potential of these extracts as environment-friendly pesticides and antifungal agents. The list of value-added products derived from sweetgum trees can be increased by continued research of this abundantly occurring tree.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/0973-7847.156307DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4441155PMC
May 2015

The functionality of plum ingredients in meat products: a review.

Meat Sci 2015 Apr 8;102:41-8. Epub 2014 Dec 8.

Department of Food Science, University of Arkansas, Fayetteville, AR, United States; Center for Food Safety, University of Arkansas, Fayetteville, AR, United States. Electronic address:

Dried plums (prunes) have been marketed to consumers for consumption directly from the package as a convenient snack and have been reported to have broad health benefits. Only recently have fractionated, dried plum ingredients been investigated for their functionality in food and feed products. Dried plum puree, dried plum fiber, dried plum powder, dried plum concentrate, and fresh plum concentrate have been investigated to date. They have been evaluated as fat replacers in baked goods, antioxidants in meat formulations, phosphate replacers in chicken marinades, and antimicrobials in food systems. Overall, dried plum products have been shown to be effective at reducing lipid oxidation and show promise as antimicrobials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.meatsci.2014.12.002DOI Listing
April 2015

Temperature effects on the antimicrobial efficacy of condensed smoke and lauric arginate against Listeria and Salmonella.

J Food Prot 2014 Jun;77(6):934-40

Sea Star International LLC, 2138 East Revere Place, Fayetteville, Arkansas 72701, USA; Department of Food Science and Center for Food Safety, University of Arkansas, Fayetteville, Arkansas 72704, USA.

Condensed smoke or liquid smoke (LS) and lauric arginate (LAE) are antimicrobials used in food preservation. They have demonstrated abilities to reduce or inhibit pathogenic and spoilage organisms. Few studies, however, have reported on the effectiveness of LS or LAE over the range of temperatures typically encountered in food marketing channels. Therefore, the effects of temperature on the antimicrobial properties of two commercial LS fractions, an LS derived from pecan shells, and LAE against two common foodborne pathogens, Listeria and Salmonella, were investigated. The MICs of the three LS samples and LAE were measured at 4, 10, and 37°C for Listeria monocytogenes strains 2045 (Scott A, serotype 4b) and 10403S (serotype 1/2a) and two strains of Listeria innocua, a well-established surrogate, and at 10, 25, and 37°C for Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Heidelberg. The MICs for LS against Listeria ranged from 3 to 48% (vol/vol), with higher MICs seen with lower temperatures. The MICs for LS on Salmonella ranged from 3 to 24%. Values for LAE ranged between 0.004 and 0.07% for both pathogens, and like LS, higher MICs were always associated with lower incubation temperatures. Understanding how storage temperature affects the efficacy of antimicrobials is an important factor that can contribute to lowering the hurdles of use levels and costs of antimicrobials and ultimately improve food safety for the consumer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4315/0362-028X.JFP-13-459DOI Listing
June 2014

Functionality of liquid smoke as an all-natural antimicrobial in food preservation.

Meat Sci 2014 Jun 9;97(2):197-206. Epub 2014 Feb 9.

Sea Star International LLC., 2138 East Revere Place, Fayetteville, AR 72701, USA; Department of Food Science and Center for Food Safety, University of Arkansas, 2650 Young Ave., Fayetteville, AR 72704, USA. Electronic address:

The smoking of foods, especially meats, has been used as a preservation technique for centuries. Today, smoking methods often involve the use of wood smoke condensates, commonly known as liquid smoke. Liquid smoke is produced by condensing wood smoke created by the pyrolysis of sawdust or wood chips followed by removal of the carcinogenic polyaromatic hydrocarbons. The main products of wood pyrolysis are phenols, carbonyls and organic acids which are responsible for the flavor, color and antimicrobial properties of liquid smoke. Several common food-borne pathogens such as Listeria monocytogenes, Salmonella, pathogenic Escherichia coli and Staphylococcus have shown sensitivity to liquid smoke in vitro and in food systems. Therefore liquid smoke has potential for use as an all-natural antimicrobial in commercial applications where smoke flavor is desired. This review will cover the application and effectiveness of liquid smoke and fractions of liquid smoke as an all-natural food preservative. This review will be valuable for the industrial and research communities in the food science and technology areas.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.meatsci.2014.02.003DOI Listing
June 2014

Identification and methionine analog tolerance of environmental bacterial isolates selected on methionine analog containing medium.

J Environ Sci Health B 2014 ;49(4):290-8

a Center for Food Safety, and Department of Food Science , University of Arkansas , Fayetteville , Arkansas , USA.

Methionine is the first limiting amino acid in poultry feed. Currently, methionine supplement is synthesized from an expensive chemical process requiring hazardous chemicals. Therefore, the objectives of this study were isolation of methionine producing bacteria from environmental samples and quantification of methionine production in these isolated bacteria. MCGC medium was selected as the isolation medium for methionine-producing bacteria by using Corynebacterium glutamicum ATCC13032 and Escherichia coli ATCC23798 as the positive and negative controls, respectively. Thirty-nine bacterial strains were obtained from environmental samples. Only strains A121, A122, A151 and A181 were able to tolerate up to 0.1% (w/v) of ethionine or norleucine. These isolated strains were identified by sequencing small subunit rRNA genes. The results revealed that bacterial strains A121, A122, A151and A181 were Klebsiella species, Acinetobacter baumannii, A. baumannii and Pseudomonas aeruginosa, respectively. When methionine production in strains A121 and A181 was quantitated, strains A121 and A181 generated methionine up to 31.1 and 124.6 μg/ml, respectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/03601234.2014.868668DOI Listing
September 2014

Efficacy of antimicrobials extracted from organic pecan shell for inhibiting the growth of Listeria spp.

J Food Sci 2013 Dec 26;78(12):M1899-903. Epub 2013 Nov 26.

Dept. of Food Science and the Center for Food Safety, Univ. of Arkansas, Fayetteville, AR, 72704, U.S.A; Sea Star Intl, LLC, 2138 E. Revere Place, Fayetteville, AR, 72701, U.S.A.

Growers and processors of USDA certified organic foods are in need of suitable organic antimicrobials. The purpose of the research reported here was to develop and test natural antimicrobials derived from an all-natural by-product, organic pecan shells. Unroasted and roasted organic pecan shells were subjected to solvent free extraction to produce antimicrobials that were tested against Listeria spp. and L. monocytogenes serotypes to determine the minimum inhibitory concentrations (MIC) of antimicrobials. The effectiveness of pecan shell extracts were further tested using a poultry skin model system and the growth inhibition of the Listeria cells adhered onto the skin model were quantified. The solvent free extracts of pecan shells inhibited Listeria strains at MICs as low as 0.38%. The antimicrobial effectiveness tests on a poultry skin model exhibited nearly a 2 log reduction of the inoculated cocktail mix of Listeria strains when extracts of pecan shell powder were used. The extracts also produced greater than a 4 log reduction of the indigenous spoilage bacteria on the chicken skin. Thus, the pecan shell extracts may prove to be very effective alternative antimicrobials against food pathogens and supplement the demand for effective natural antimicrobials for use in organic meat processing.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1750-3841.12311DOI Listing
December 2013

Characterization of isolated yeast growth response to methionine analogs.

J Environ Sci Health B 2013 ;48(12):1112-20

Center for Food Safety, and Department of Food Science, University of Arkansas, Fayetteville, AR 72704-5690, USA.

Methionine is one of the first limiting amino acids in poultry nutrition. The use of methionine-rich natural feed ingredients, such as soybean meal or rapeseed meal may lead to negative environmental consequences. Amino acid supplementation leads to reduced use of protein-rich ingredients. The objectives of this study were isolation of potentially high content methionine-containing yeasts, quantification of methionine content in yeasts and their respective growth response to methionine analogs. Minimal medium was used as the selection medium and the isolation medium of methionine-producing yeasts from yeast collection and environmental samples, respectively. Two yeasts previously collected along with six additional strains isolated from Caucasian kefir grains, air-trapped, cantaloupe, and three soil samples could grow on minimal medium. Only two of the newly isolated strains, K1 and C1, grew in minimal medium supplied with either methionine analogs ethionine or norleucine at 0.5% (w/v). Based on large subunit rRNA sequences, these isolated strains were identified as Pichia udriavzevii/Issatchenkia orientalis. P. kudriavzevii/I. orentalis is a generally recognized as a safe organism. In addition, methionine produced by K1 and C1 yeast hydrolysate yielded 1.3 ± 0.01 and 1.1 ± 0.01 mg g(-1) dry cell. Yeast strain K1 may be suitable as a potential source of methionine for dietary supplements in organic poultry feed but may require growth conditions to further increase their methionine content.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/03601234.2013.824305DOI Listing
April 2014

Whole-chain traceability, is it possible to trace your hamburger to a particular steer, a U. S. perspective.

Meat Sci 2013 Oct 16;95(2):137-44. Epub 2013 Apr 16.

Center for Food Safety and Department of Food Science, University of Arkansas, Fayetteville, AR 72704, United States.

Traceability through the entire food supply chain from conception to consumption is a pressing need for the food industry, consumers and government regulators. A robust, whole-chain traceability system is needed that will effectively address food quality, food safety and food defense issues by providing real-time, transparent and reliable information from beef production through slaughter and distribution to the consumer. Traceability is an expanding part of the food safety continuum that minimizes the risk of foodborne diseases, assures quality and cold-chain integrity. Traceability can be a positive competitive marketing edge for beef producers who can verify specific quality attributes such as humane production or grass fed or Certified Organic. In this review we address the benefits as well as the remaining issues for whole-chain traceability in the beef industry, with particular focus on ground beef for the markets in the United States.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.meatsci.2013.04.022DOI Listing
October 2013

Acridine orange as an alternative to optical density to study growth kinetics of Lactobacillus bulgaricus ATCC 7517.

J Environ Sci Health B 2013 ;48(6):512-5

Center for Food Safety, Dept. of Food Science, University of Arkansas, Fayetteville, Arkansas, USA.

In this study we assessed the use of acridine orange as an alternative to optical density to quantify the growth of Lactobacillus bulgaricus ATCC 7517. The growth of bacteria in Lactobacillus de Man Rogosa Sharpe (MRS) medium was measured by both acridine orange (AO) and optical density (OD) measurements for 24 h. The relationship between both methods was compared via correlation analysis. The doubling time of bacteria based on the values of OD600 and AO obtained during 24 h growth were also calculated. The result shows strong correlation of cell growth between OD600 and AO during the first 10 hours of growth, but the correlation was less strong when analyzing the data from 0 to 24 hours. Growth rates, generation time and lag time were also similar. This study indicates that AO could be used in place of OD to prepare growth curves of Lactobacillus bulgaricus during the exponential phase of growth, and to compare growth rates, generation times or lag times.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/03601234.2013.761919DOI Listing
August 2013

Physicochemical analysis of wheat flour fortified with vitamin A and three types of iron source and sensory analysis of bread using these flours.

J Sci Food Agric 2013 Jul 1;93(9):2299-307. Epub 2013 Feb 1.

Department of Food Science, University of Arkansas, 2650 North Young Avenue, Fayetteville, AR 72704, USA.

Background: Wheat flour is increasingly being fortified worldwide with vitamin A and iron. Research on high levels of fortification is limited; therefore, in this study, wheat flour was made under controlled conditions fortified with vitamin A at 30 000 or 70 000 retinol equivalents (RE) kg⁻¹ and three types of iron source at 66 mg kg⁻¹.

Results: Milling produced a uniform distribution of fortificants with no significant separation during packaging or transportation. Chemical and physical analyses demonstrated that the dual fortified flours had acceptable physicochemical properties of mixing tolerance, pasting curves, damaged starch and falling numbers. The level of vitamin A fortification compensated for initial loss caused during wheat processing. Overall, white breads baked from seven treatments of fortified flour had only 22% (eight out of 36) of the sensory attributes as being significantly different. However, the type of iron source may play a key role in modulating the sensory attributes of bread baked from the dual fortified flour with vitamin A and iron.

Conclusion: The findings suggest that dual fortified flour with high or even lower levels of vitamin A and iron could be considered for food fortification programmes to reduce the prevalence of micronutrient undernutrition of vitamin A and iron in developing countries.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jsfa.6043DOI Listing
July 2013

Antimicrobial properties of three lactic acid bacterial cultures and their cell free supernatants against Listeria monocytogenes.

J Environ Sci Health B 2013 ;48(1):63-8

Center for Food Safety, University of Arkansas, Fayetteville, Arkansas, USA.

Control of Listeria monocytogenes in ready-to-eat (RTE) food products is a significant challenge and improved means for control are needed. In this study, the anti-listerial effects of three lactic acid bacteria (LAB) were investigated. Spot-on-lawn assays demonstrated the largest zones of inhibition against L. monocytogenes were produced by the Pediococcus acidilactici strain, with zone diameters ranging from 13 to 18 mm. Minimum inhibitory concentration (MIC) experiments using cell free supernatant (CFS) from the LAB revealed that while two of the strains were effective at inhibiting L. monocytogenes growth only up to a 1:4 dilution, P. acidilactici was able to inhibit growth up to a 1:256 dilution. Survival assays performed at 7°C determined that the P. acidilactici strain was capable of producing a 4.5 log reduction in L. monocytogenes counts and maintaining the reduction for 21 days. The effectiveness of P. acidilactici was reduced under log phase growth, autoclaving for longer than 15 min (121°C and 15 psi), and treatment with proteinase K (25 mg/mL).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/03601234.2012.716732DOI Listing
February 2013

Application of orange essential oil as an antistaphylococcal agent in a dressing model.

BMC Complement Altern Med 2012 Aug 16;12:125. Epub 2012 Aug 16.

Center for Food Safety and Department of Food Science, University of Arkansas, Fayetteville, AR 72701, USA.

Background: Staphylococcus aureus is the pathogen most often and prevalently involved in skin and soft tissue infections. In recent decades outbreaks of methicillin-resistant S. aureus (MRSA) have created major problems for skin therapy, and burn and wound care units. Topical antimicrobials are most important component of wound infection therapy. Alternative therapies are being sought for treatment of MRSA and one area of interest is the use of essential oils. With the increasing interest in the use and application of natural products, we screened the potential application of terpeneless cold pressed Valencia orange oil (CPV) for topical therapy against MRSA using an in vitro dressing model and skin keratinocyte cell culture model.

Methods: The inhibitory effect of CPV was determined by disc diffusion vapor assay for MRSA and vancomycin intermediate-resistant S. aureus (VISA) strains. Antistaphylococcal effect of CPV in an in vitro dressing model was tested on S. aureus inoculated tryptic soya agar plate. Bactericidal effect of CPV on MRSA and VISA infected keratinocyte cells was examined by enumeration of extra- and intra-cellular bacterial cells at different treatment time points. Cytotoxic effects on human skin cells was tested by adding CPV to the keratinocyte (HEK001) cells grown in serum free KSFM media, and observed by phase-contrast microscope.

Results: CPV vapour effectively inhibited the MRSA and VISA strains in both disc diffusion vapour assay and in vitro dressing model. Compared to untreated control addition of 0.1% CPV to MRSA infected keratinocyte decreased the viable MRSA cells by 2 log CFU/mL in 1 h and in VISA strain 3 log CFU/mL reduction was observed in 1 h. After 3 h viable S. aureus cells were not detected in the 0.2% CPV treatment. Bactericidal concentration of CPV did not show any cytotoxic effect on the human skin keratinocyte cells in vitro.

Conclusions: At lower concentration addition of CPV to keratinocytes infected with MRSA and VISA rapidly killed the bacterial cells without causing any toxic effect to the keratinocytes. Therefore, the results of this study warrant further in vivo study to evaluate the potential of CPV as a topical antistaphylococcal agent.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/1472-6882-12-125DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3522527PMC
August 2012

Role of lactic acid bacteria as a biosanitizer to prevent attachment of Listeria monocytogenes F6900 on deli slicer contact surfaces.

J Food Prot 2012 Aug;75(8):1429-36

Center for Food Safety, Department of Food Science, University of Arkansas, Fayetteville, AR 72704, USA.

The study was conducted to evaluate the attachment of three lactic acid bacteria (LAB) strains and their combination in a cocktail, to stainless steel coupons from a deli slicer, and their ability to inhibit the attachment of Listeria monocytogenes. In a previous study, three LAB strains, Pediococcus acidilactici, Lactobacillus amylovorus, and Lactobacillus animalis, were isolated from ready-to-eat meat and exhibited antilisterial effect. In the study reported here, hydrophobicity tests were determined according to the method of microbial adhesion to solvent. The attachment of the cells was evaluated on stainless steel coupons from deli slicers. Extracellular carbohydrates were determined with a colorimetric method. Based on these tests, L. animalis exhibited the greatest hydrophobicity (26.3%), and its adherence increased sharply from 24 to 72 h, whereas L. amylovorus yielded the lowest hydrophobicity (3.86%) and was weakly adherent. Although P. acidilactici had moderate hydrophobicity (10.1%), it adhered strongly. The attached LAB strains produced significantly (P < 0.05) higher total carbohydrates than their planktonic counterparts did, which is an important characteristic for attachment. Three conditions were simulated to evaluate the ability of the LAB cocktail (10(8) CFU/ml) to competitively exclude L. monocytogenes (10(3) CFU/ml) on the surface of the coupons. The coupons were pretreated with the LAB cocktail for 24 h prior to the addition of L. monocytogenes, simultaneously treated with the LAB cocktail and L. monocytogenes, or pretreated with L. monocytogenes 24 h prior to the addition of the LAB cocktail. The LAB cocktail was able to reduce the attachment L. monocytogenes significantly (P < 0.05). The LAB cocktail indicated potential attachment on stainless steel and bacteriostatic activity toward L. monocytogenes attached on stainless steel, which indicates a possible role for LAB as a biosanitizer in the food industry.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4315/0362-028X.JFP-12-072DOI Listing
August 2012

Antimicrobial activity of lactic acid bacteria against Listeria monocytogenes on frankfurters formulated with and without lactate/diacetate.

Meat Sci 2012 Dec 28;92(4):533-7. Epub 2012 May 28.

Center for Food Safety, Dept. of Food Science, University of Arkansas, Fayetteville, AR 72704, USA.

Contamination by Listeria monocytogenes has been a constant public health threat for the ready-to-eat (RTE) meat industry due to the potential for high mortalities from listeriosis. Lactic acid bacteria (LAB) have shown protective action against various pathogenic bacteria. The aim of this study was to evaluate the antilisterial activity of a combination of three LAB strains (Lactiguard®) on L. monocytogenes. The combination of the LAB was inhibitory to L. monocytogenes inoculated onto frankfurters not containing lactate/diacetate after 8weeks of refrigerated storage (0.6 log reduction compared to L. monocytogenes only control), and when a cell free extract (CFS) of the LAB was added with LAB even more inhibition was obtained (1.2 log reduction compared with L. monocytogenes only). In frankfurters containing lactate/diacetate the LAB and the LAB plus CFS were more effective in reducing growth of L. monocytogenes after 8 weeks of refrigerated storage (2 and 3.3 log reductions respectively).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.meatsci.2012.05.023DOI Listing
December 2012

Screening of commercial and pecan shell-extracted liquid smoke agents as natural antimicrobials against foodborne pathogens.

J Food Prot 2012 Jun;75(6):1148-52

Department of Food Science and Center for Food Safety, University of Arkansas, Fayetteville, Arkansas 72704, USA.

Liquid smoke extracts have traditionally been used as flavoring agents, are known to possess antioxidant properties, and serve as natural alternatives to conventional antimicrobials. The antimicrobial efficacies of commercial liquid smoke samples may vary depending on their source and composition and the methods used to extract and concentrate the smoke. We investigated the MICs of eight commercial liquid smoke samples against Salmonella Enteritidis, Staphylococcus aureus, and Escherichia coli . The commercial liquid smoke samples purchased were supplied by the manufacturer as water-based or concentrated extracts of smoke from different wood sources. The MICs of the commercial smokes to inhibit the growth of foodborne pathogens ranged from 0.5 to 6.0% for E. coli, 0.5 to 8.0% for Salmonella, and 0.38 to 6% for S. aureus. The MIC for each liquid smoke sample was similar in its effect on both E. coli and Salmonella. Solvent-extracted antimicrobials prepared using pecan shells displayed significant differences between their inhibitory concentrations depending on the type of solvent used for extraction. The results indicated that the liquid smoke samples tested in this study could serve as effective natural antimicrobials and that their inhibitory effects depended more on the solvents used for extraction than the wood source.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4315/0362-028X.JFP-11-543DOI Listing
June 2012

Dried plum products as a substitute for phosphate in chicken marinade.

J Food Sci 2012 Jun;77(6):S253-7

Dept. of Food Science and Center for Food Safety, Univ of Arkansas, Fayetteville, AR 72704, USA.

Unlabelled: In order to address the growing demand for more natural poultry products, alkaline phosphates commonly used in chicken breast meat marinades were replaced with plum ingredients and evaluated. For initial sensory evaluation, 200 consumers of chicken were served a small portion of the chicken breast on a plate and were asked to evaluate the product for overall impression, flavor, and texture on a 9-point hedonic scale with 1 = "dislike extremely" and 9 = "like extremely." Also, a 5-point just-about-right (JAR) scale was used on questions about tenderness, juiciness, overall flavor, and saltiness. Both hedonic and JAR demonstrated that the marinades of plum concentrate and the blend of plum fiber and powder were not distinguishable from the control (P > 0.05). Using two different percentages of fiber/powder blend, two different percentages of concentrate, sodium tripolyphosphate (STPP), and no marinade, measurements were made for marinade per cent pickup, thaw loss, and cook loss. Plum concentrate at 1.1% was most similar to STPP in marinade per cent pickup, thaw loss, drip loss, and cook loss. These results show that plum ingredients can potentially be used as a substitute in standard phosphate marinades.

Practical Application: Consumers are increasingly demanding more natural foods with less artificial additives. This research presents the results of experiments using dried plum ingredients as a substitute for phosphates commonly used in marinades for chicken. Results indicate that dried plum ingredients may be a suitable substitute for phosphates in marinades.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1750-3841.2012.02737.xDOI Listing
June 2012

A review of the ecology, genomics, and stress response of Listeria innocua and Listeria monocytogenes.

Crit Rev Food Sci Nutr 2012 ;52(8):712-25

Center for Food Safety IFSE and Department of Food Science, University of Arkansas, Fayetteville, AR 72704, USA.

Listeria monocytogenes is a Gram-positive foodborne pathogen responsible for a severe disease occurring in immuno-compromised populations. Foodborne illness caused by L. monocytogenes is a serious public health concern because of the high associated mortality. Study of the closely related, but nonpathogenic Listeria innocua has accounted for a better understanding of the behavior of L. monocytogenes in environments beyond the laboratory. Traditionally, the ecological co-habitation, genomic synteny, and physiological similarity of the two species have supported use of L. innocua for predicting the behavior of L. monocytogenes in farm and food processing environments. However, a careful review of the current literature indicates that in a given situation it may not be prudent to use L. innocua as a surrogate for L. monocytogenes without prior confirmation of their similar phenotypes, as an increasing number of studies have arisen demonstrating differences in L. monocytogenes and L. innocua stress response, and furthermore, there are differences among the L. monocytogenes subgroups. Future research should take into consideration that multiple surrogates might be required to accurately model even a single condition depending on the L. monocytogenes subgroup of interest.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/10408398.2010.507909DOI Listing
September 2012

Inhibition of beef isolates of E. coli O157:H7 by orange oil at various temperatures.

J Food Sci 2012 Jun 14;77(6):M308-11. Epub 2012 May 14.

Center for Food Safety-IFSE and Food Science Dept, 2650 Young Ave, Univ of Arkansas, Fayetteville, AR 72704, USA.

Unlabelled: Plant essential oils have previously been shown to exhibit antimicrobial activities against various microorganisms. In this study, cold pressed terpeneless Valencia orange oil (CPTVO) was examined at various temperatures (37, 10, and 4 °C) to determine its antimicrobial activity against 3 strains of E. coli O157:H7 recovered from beef products. A micro broth dilution method using 96 well microtiter plates was used with trypticase soy broth with 0.15% agar and 2,3,5 tetrazolium chloride as a growth indicator as the medium. Serial dilutions of CPTVO were made, resulting in final concentrations of oil ranging from 0.2% to 25% or 0.1% to 10%. Plates were incubated statically at 4, 10, or 37 °C, and sampled hourly. After 6 h at 37 °C, all strains were inhibited at concentrations ranging from 0.2% to 0.6%, with a mean of 0.4 ± 0.01%. At 10 °C, all strains were inhibited at concentrations ranging from 0.8% to 6.3%, with a mean of 1.1% ± 0.2%, after 6 h. At 4 °C, all strains were inhibited after 6 h at concentrations ranging from 2.3% to 4.6%, with a mean of 3.5% ± 2.1%. After 24 h at 4 °C the strains were inhibited at concentrations ranging from 0.7% to 1% with a mean of 0.8% ± 0.3%. The ranges appear to be the result of effects from the variable nature of a complex media and an antimicrobial that presents potential multiple mechanisms for inhibition. It appears CPTVO is a viable option to inhibit E. coli O157:H7 growth at refrigeration temperatures.

Practical Application: Beef products are often the source of foodborne illness from the organism E. coli O157:H7. Orange essential oils have been in the human diet for centuries, and the research reported here indicates that some of these oils may be used as surface applications during cold temperatures to inhibit the foodborne pathogen E. coli O157:H7.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1750-3841.2012.02689.xDOI Listing
June 2012

In vitro effects of citrus oils against Mycobacterium tuberculosis and non-tuberculous Mycobacteria of clinical importance.

J Environ Sci Health B 2012 ;47(7):736-41

Center for Food Safety and Department of Food Science, University of Arkansas, Fayetteville, Arkansas, USA.

We evaluated the in vitro activity of citrus oils against Mycobacterium tuberculosis and other non-tuberculous Mycobacterium species. Citrus essential oils were tested against a variety of Mycobacterium species and strains using the BACTEC radiometric growth system. Cold pressed terpeneless Valencia oil (CPT) was further tested using the Wayne model of in vitro latency. Exposure of M. tuberculosis and M. bovis BCG to 0.025 % cold pressed terpeneless Valencia orange oil (CPT) resulted in a 3-log decrease in viable counts versus corresponding controls. Inhibition of various clinical isolates of the M. avium complex and M. abscessus ranged from 2.5 to 5.2-logs. Some species/strains were completely inhibited in the presence of CPT including one isolate each of the following: the M. avium complex, M. chelonae and M. avium subsp. paratuberculosis. CPT also inhibited the growth of BCG more than 99 % in an in vitro model of latency which mimics anaerobic dormancy thought to occur in vivo. The activity of CPT against drug-resistant strains of the M. avium complex and M. abscessus suggest that the mechanism of action for CPT is different than that of currently available drugs. Inhibition of latently adapted bacilli offers promise for treatment of latent infections of MTB. These results suggest that the antimycobacterial properties of CPT warrant further study to elucidate the specific mechanism of action and clarify the spectrum of activity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/03601234.2012.669331DOI Listing
August 2012

Comparison of nitroethane, 2-nitro-1-propanol, lauric acid, Lauricidin® and the Hawaiian marine algae, Chaetoceros, for potential broad-spectrum control of anaerobically grown lactic acid bacteria.

J Environ Sci Health B 2012 ;47(4):269-74

Department of Animal Science, Faculty of Agriculture, University of Novi Sad, Republic of Serbia.

The gastrointestinal tract of bovines often contains bacteria that contribute to disorders of the rumen, and may also contain foodborne or opportunistic human pathogens as well as bacteria capable of causing mastitis in cows. Thus there is a need to develop broad-spectrum therapies that are effective while not leading to unacceptably long antibiotic withdrawal times. The effects of the CH(4)-inhibitors nitroethane (2 mg/mL), 2-nitro-1-propanol (2 mg/mL), lauric acid (5 mg/mL), the commercial product Lauricidin® (5 mg/mL), and a finely ground product of the Hawaiian marine algae, Chaetoceros (10 mg/mL), were compared in pure cultures of Streptococcus agalactia, Enterococcus faecium, Streptococcus bovis, and in a mixed lactic acid rumen bacterial culture. Lauricidin® and lauric acid exhibited the most bactericidal acidity against all bacteria. These results suggest potential animal health benefits from supplementing cattle diets with lauric acid or Lauricidin® to improve the health of the rumen and help prevent shedding of human pathogens.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/03601234.2012.638883DOI Listing
July 2012
-->