Progress 01/01/12 to 12/31/16
Outputs
Target Audience:Food service personnel, Industry/commodity groups, food processors, regulatory agencies (FDA, FSIS), and consumer groups Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Interns have been placed with researchers to learn to control and study STEC bacteria throughout the entire beef system, leading to improvements in beef safety and public health. Interns [N=14] were funded by the USDA CAP grant focused on pathogenic E. coli. Outputs: The 14 interns were placed, finished their internships and reported their findings at the annual meeting of the CAP grant. How have the results been disseminated to communities of interest?Journal articles and conference papers. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
A method using isobutylchloroformate (IBCF) and gas chromatography mass-spectrometry (GC-MS) was developed to detect and quantify the possible cancer compound 4(5)-methylimidazole (4-MeI) in processed meat products. Levels of 4-MeI ranged from 0.04 to 1.01 ug/g with recovery of 94.76 to 103.94%. Formation of 4-MeI in glucose-amino acid model system was studied. D-Glucose (Glu) was mixed individually in equimolar concentrations of 0.05, 0.1, or 0.15 M and equal volume with L-Alanine (Ala), L-Arginine (Arg), Glycine (Gly), L-Lysine (Lys), and L-Serine (Ser); and the mixtures were heat treated at 60, 120, and 160°C for 1 h. Among all tested amino acids, Glu-Arg produced the highest level of 4-MeI. The, Glu-Lys model system showed higher browning and lower concentrations of 4-MeI. The effect of ascorbic acid (ASA), a strong antioxidant, was studied in the Glu-Arg model system. Four concentrations of ASA (0.0375, 0.075, 0.15, and 0.3 M) were mixed with 0.15 M equimolar of Glu-Arg and heat treated at 160°C for 1h. ASA inhibited formation of 4-MeI by 40.29, 69.94, 75.13, and 96.25% for the 0.0375, 0.075, 0.15, and 0.3 M concentrations. Ascorbic acid increased the browning in all treatments compared to controls by 10.67, 15.47, 18.4, and 28.8% for the 0.0375, 0.075, 0.15, and 0.3 M concentrations. Adding ASA to processed food may reduce formation of 4-MeI and increase the browning that is a desired attribute. Advanced glycation endproducts (AGEs) are formed in many cooked meat products via Maillard browning reactions. We determined the AGE content, as determined as N-carboxymethyllysine (CML) level, in cooked meat and fish prepared by general cooking methods recommended by U.S. Department of Agriculture, Food Safety and Inspection Service (USDA-FSIS). AGEs were detected in all the cooked samples, but the levels depended on the different cooking conditions. Broiling and frying at higher cooking temperatures produced higher levels of CML and broiled beef contained the highest CML content (21.84 ug/g). However, the baked salmon (8.59 ug/g) and baked tilapia (9.72 ug/g) contained less CML as compared to the other samples. In order to investigate the inhibitory effect of selected natural antioxidant on AGEs formation in cooked meat, four cereal brans, wheat (Jagger, JA), triticale (Spring Triticale, ST; Thundercale, TH), and Rye (RY) bran were added to beef patties before cooking. RY (42.0% inhibition), ST (27.5% inhibition), and TH (21.4% inhibition) brans significantly decreased CML formation compared with the control. Previous research showed that radio frequency dielectric heating (RFDH) (combined with subsequent hold period in a convection oven) could be used as a post-process lethality treatment for high-heat (HH) and low-heat (LH) non-fat dry milk (NDM). This information has significant impact for the food industry, especially those that produced powdered products. Nevertheless, the impact of this dry heat treatment on the chemical components in NDM was unknown, as evidence suggested that this dry heat treatment influenced protein interactions. Thus, LH-NDM or HH-NDM were heated to 75?C, 80?C, or 85?C in the RFDH and held times ranging from 125 to 11 min, reflecting 5-log reduction in pathogens. Samples were evaluated for heat stability over a pH range of 6.4 to 7.4. Results showed that the RFDH treatment of HH-NDM did not affect the HCT. However, the RFDH-treated LH-NDM exhibited increased heat stability when the pH was close to their native pH or pH 6.8. Results from the WPNI test suggested that the whey protein denaturation that occurred during the RFDH process (~ 11% for LH-75?C, 10% for LH-80?C and 6% for LH-85?C compared with non-treated LH-NDM), may improve the heat stability. Secondly, LH-NDM was heated to 80, 85, and 90°C in an RFDH unit and held for 60, 90 or 180 min. RFDH-treated LH-NDM (85°C for 90 min) exhibited improved foaming properties and heat stability, minimal color change, while maintaining solubility. Results of the SDS-PAGE and WPNI tests indicated that this heat treatment induced more whey protein denaturation and produced more aggregates that are soluble. These results combined with surface hydrophobicity and casein micelle distributions, suggest that the protein interactions induced by the dry heat treatment had different bonding mechanisms, resulting in alternations of the protein-protein structure. The process of denaturing whey proteins in a dry system (RFDH treatment) vs. liquid system (HH-NDM vs. LH-NDM) may produce different whey protein complexes that may provide protection against heat coagulation. Fresh ground beef, pork, and turkey with NaCl, KCl, CaCl2, MgCl2, sea salt, and replacement salt (2.0%) were inoculated with Listeria monocytogenes to determine growth/survival during 5 d at 4 °C to simulate a pre-blend process. Listeria monocytogenes populations significantly decreased (0.41 log CFU/g) during the storage time in beef, however no differences (P>0.05) were observed over time in pork or turkey. Salt type did not affect (P>0.05) Listeria monocytogenes populations during pre-blend storage. However, salts (MgCl2 and NaCl) showed growth (P<0.05) of aerobic populations during storage. Emulsified beef and pork products were processed with NaCl, KCl, sea salt and a NaCl/KCl blend (2%) and post-processed surface inoculated with Listeria monocytogenes (five-strain cocktail) to determine growth/survival at 4 °C for 28 d. Pork products showed greater (P<0.05) Listeria monocytogenes population growth at all sampling times than beef products; whereas salt type had no effect on Listeria monocytogenes populations. Treatments to reduce Escherichia coli O157:H7 and Escherichia coli surrogates, Salmonella spp., and Listeria monocytogenes populations on the surface of green leaf lettuce, tomatoes, and cantaloupes were evaluated to validate washing solutions in reducing pathogens on produce surfaces. Lettuce (25 ± 0.3g) and tomatoes were inoculated with E. coli O157:H7 and Salmonella spp., respectively. Samples were treated with tap water (TW) or a chemical wash treatment (CWT; containing citric acid) for 30, 60, or 120 s. Reduction of E. coli O157:H7 and Salmonella spp. populations on the surface of leaf lettuce and tomatoes, respectively, were greater (P<0.05) for CWT (ca. 3.0 logs) than for TW (ca. 2.3- 2.5 logs). Cantaloupes were washed with TW, 9% vinegar solution, or a commercial antimicrobial for fruit and vegetables treatment (CAFVT; containing lactic acid) for 2 min using a washing system. Cantaloupes were cut into wedges or cubes and stored at 4ºC for aerobic plate counts (APC) on days 0, 1, 3, and 6. APC populations of cubed and wedged cantaloupes were different over time (P=0.00052); cantaloupes washed with 9% vinegar solution showed the lowest APC populations after day 1 and 3 of storage. Salmonella spp. or L. monocytogenes inoculated cantaloupes were washed with CPW for 30, 60 or 120 s. Washing cantaloupes for 120 s with CPW showed greater (P<0.05) reductions of Salmonella spp. and L. monocytogenes populations (1.26 and 1.12 log?? CFU/cm²) than TW (ca. 0.63 log?? CFU/cm²) on cantaloupe surface. Lettuce leaves were inoculated with rifampicin-resistant E. coli surrogates and then washed with CAFVT, 5% vinegar solution or TW for 2 min with agitation (washing system) or without. Log reductions of CAFVT (2.25 log?? CFU/g) were greater (P=0.0145) than those by tap water (1.34 log?? CFU/g), but similar to 5% vinegar solution (2.09 log?? CFU/g). Washing lettuce with continuous agitation achieved higher (P=0.0072) E. coli reductions (2.26 log?? CFU/g) than without agitation (1.53 log?? CFU/g). Overall, incorporation of wash solutions or agitation (washing system) in the washing process compared to TW alone reduced greater (P<0.05) APC, pathogens, or surrogates populations from lettuce, tomato, and cantaloupe surfaces.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2016
Citation:
Lopez, K., Milke, D., Bloedow, N., and Getty, K.J.K. 2016. Efficacy of a washing system and commercial produce washes to reduce Escherichia coli surrogates on green leaf lettuce surface. Ann. Mtg. Inst. of Food Technologist Chicago, IL, July 16-19, 2016. Program Book.
- Type:
Journal Articles
Status:
Accepted
Year Published:
2016
Citation:
Faris Karim, Faris, J. Scott Smith. Formation of 4(5)-Methylimidazole in Aqueous
D-Glucose-Amino Acids Model System. 2016. J. Food Science. 81:T268-T274.
|
Progress 10/01/15 to 09/30/16
Outputs
Target Audience:Food service personnel, Industry/commodity groups, food processors, regulatory agencies (FDA, FSIS), and consumer groups Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Interns have been placed with researchers to learn to control and study STEC bacteria throughout the entire beef system, leading to improvements in beef safety and public health. Interns [N=14] were funded by the USDA CAP grant focused on pathogenic E. coli. Outputs: The 14 interns were placed, finished their internships and reported their findings at the annual meeting of the CAP grant. How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Previous research showed that radio frequency dielectric heating (RFDH) (combined with subsequent hold period in a convection oven) could be used as a post-process lethality treatment for high-heat (HH) and low-heat (LH) non-fat dry milk (NDM). However this impact of this heat treatment on NDM is not fully understood. Thus, in project 1, LH-NDM and HH-NDM were heated to various temperatures in the RFDH (75°C, 80°C, or 85°C) and held at that temperatures for a period of time (125 to 11 min). Results showed that the RFDH treatment of HH-NDM did not affect the HCT. However, the RFDH treatment caused the LH-NDM samples to exhibit increased HCT when the pH was close to their native pH or pH 6.8. Results from the WPNI test suggested that the whey protein denaturation that occurred during the RFDH process (~ 11% for LH-75°C, 10% for LH-80°C and 6% for LH-85°C compared with non-treated LH-NDM), may improve the heat stability. LH-NDM was heated to 80, 85, and 90°C in an RFDH unit and then held at that temperature for 60 or 90 min. Results showed that LH-NDM heated to 85°C and held for 90 minutes exhibited improved foaming properties and heat stability, minimal color change, while maintaining solubility. Results of the SDS-PAGE and WPNI tests, indicated that this heat treatment induced more whey protein denaturation, which would explain the foaming results. Different heat treatments could cause specific protein structure alterations that in turn provide improved functionality in food systems. The process of denaturing whey proteins in a dry system (RFDH treatment) vs. liquid system (HH-NDM vs. LH-NDM) may produce different whey protein complexes that may provide protection against heat coagulation. Milk fouling and biofilms are common problems in the dairy industry across many types of processing equipment. One way to achieve a reduction in milk fouling and biofilms is to modify the surface characteristics of milk contact surfaces. This study examines the potential viability of using ThermolonTM, a sol-gel-based surface modification on stainless steel (SS), during thermal processing of milk. SS 316 L as control and sol-gel-modified coupons were used in this study to evaluate the fouling behavior and bacterial adhesion. The modified surface also had a lower surface energy (32.4±1.4 mN/m) compared to the control (41.36±2.7 mN/m) and a significant reduction in the amount of fouled layer on modified surfaces. Overall, ThermolonTM modified surface showed potential in thermal processing of milk, offering significantly lower fouling and bacterial attachment as compared to SS control surface. A survey was conducted with school food service personnel to validate washing solutions and techniques in reducing pathogens on produce surfaces. Information about cantaloupes and leaf lettuce were used to develop a validation study. Cantaloupes were washed with tap water (TW), 9% vinegar solution, or a commercial antimicrobial containing lactic acid (CA) for 2 min using a washing system. Cantaloupes washed with 9% vinegar solution showed the lowest aerobic plate count (APC) populations after day 1 and 3 of storage. Lettuce leaves were inoculated with rifampicin-resistant Escherichia coli surrogates and then washed with CA, 5% vinegar solution or TW for 2 min with agitation (washing system) or without. Log reductions of CA (2.25 log CFU/g) were greater (P=0.015) than those by TW (1.34 log CFU/g), but similar to 5% vinegar solution (2.09 log CFU/g). Overall, incorporation of wash solution or agitation (washing system) in the produce washing process compared to TW alone reduce greater (P<0.05) APC or surrogates populations. Shiga toxin-producing E. coli (STEC) are frequently associated with foodborne illness outbreaks, especially attributable to beef. Intervention methods, such as water washes and organic acid application, are widely implemented across the beef industry to combat this risk. This research evaluates the efficacy of intervention methods applied to chilled beef subprimal pieces and pre-rigor beef carcasses to reduce STEC contamination. Beef strip loins were inoculated (ca. 5 log CFU/cm2) with a 7-serotype STEC cocktail and sprayed with increasing concentrations of peracetic acid (200-1800 ppm), lactic acid (3-10%), or a water control before being vacuum-packaged and stored for 24 h at 4°C. Meat surface excision samples and color readings (L*, a*, and b*) were obtained from each subprimal at three sampling points: post-inoculation, 5 min post chemical spray, and post-24 h vacuum packaged chilling. Peracetic acid spray and lactic acid spray reduced STEC populations by 0.5 -1.3 log CFU/cm2 and 0.2 - 0.7 log CFU/cm2, respectively. All concentrations of peracetic acid and lactic acid concentrations =3.5% reduced (P = 0.05) STEC populations compared to their respective control. Carcass intervention methods were evaluated using a three-stage commercial carcass washing cabinet (Chad Equipment). Four pre-rigor carcass sides were inoculated by electrostatic spraying with a 7-serogroup STEC cocktail (ca. 6.5 log CFU/100 cm2). Three treatments were applied, in order, to each side: ambient water wash, hot water wash, and antimicrobial mist. Meat surface excision samples were taken from the bottom, middle, and top section of each carcass side at five sampling points: 30 min post-inoculation, post-ambient water wash, post-hot water wash, post-antimicrobial spray, and after 18 h spray chilling. The combination of the ambient water stage and subsequent hot water stage reduced STEC population on sides by 3.5, 4.7, and 4.8 log CFU/100 cm2 at the bottom, middle, and top of the carcass, respectively. Due to STEC populations reaching very low or undetectable levels after the hot water stage, minimal additional STEC reductions were observed after chemical spray application and chilling. Maillard model systems containing glucose, creatinine, and phenylalanine were used to investigate the inhibitory effects of amino acids on the formation of 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP), a know carcinogen formed in the grilling/frying of muscle food products. HPLC analysis showed that amino acids were able to reduce PhIP levels in a dose-dependent response, ranking as: Trp > Lys > Pro > Leu > Met > Val > Ile > Thr > Phe > Asp. Browning development (420 nm) in model systems was shown to be retarded by most amino acids, except for Trp. Furthermore, phenylacetaldehyde (PheAce) which is one of the Maillard intermediates was proportionally reduced. A high correlation between the PhIP inhibition and amino acids' PheAce-scavenging activity was observed when PheAce and amino acids were directly heated at 180 °C for 1 h, and was further confirmed by linear regression models. Results obtained by this study suggested that in addition to using plant-based extracts/antioxidants, amino acids can be used to inhibit PhIP formation. The formation of 4-MeI, a suspected carcinogen produced during Maillard browning color formation, was evaluated in a D-glucose (Glu) amino acids (AA) model system. Several amino acids such as L-Alanine (Ala), L-Arginine (Arg), Glycine (Gly), L-Lysine (Lys), and L-Serine (Ser) were mixed individually with Glu at 3 concentrations (0.05, 0.1, and 0.15 M). The Glu-AA mixtures were reacted at 60, 120, and 160 °C for 1 h. No 4-MeI was formed at 60 °C for any treatment combination; however, at 120 °C and 0.05 M, Glu-Arg and Glu-Lys produced 0.13 and 0.14 mg/kg of 4-MeI. At 160 °C and 0.05 M all treatment combinations formed 4-MeI. At 160 °C and 0.15 M, the observed levels of Glu-Ala, Glu-Arg, Glu-Gly, Glu-Lys, and Glu-Ser were 0.21, 1.00, 0.15, 0.22, and 0.16 mg/kg. Glu-Lys treatment in all combinations produced the most browning, but Glu-Arg produced the most 4-MeI. This method showed that foods processed using low temperatures may have reduced levels of 4-MeI.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2016
Citation:
Balasubramanian, S., J. K. Amamcharla, and J.E. Shin. 2016. Possible Application of Electronic Nose Systems for Meat Safety: An Overview. Pages 59-72 in The Electronic Nose and Tongue in Food Science. Mendez, M.R. and V. Preedy, ed. Academic Press, London, UK.
Channaiah, L.H., E.S. Holmgren, M. Michael, N.J. Sevart, D. Milke, C.L. Schwan, M. Krug, A. Wilder, R.K. Phebus, H. Thippareddi, and G. Milliken. 2016. Validation of baking to control Salmonella Serovars in hamburger bun manufacturing, and evaluation of Enterococcus faecium ATCC 8459 and Saccharomyces cerevisiae as nonpathogenic surrogate indicators. J. Food Prot. 79:544-552.
Faris Karim, J. Scott Smith. 2016. Formation of 4(5)-Methylimidazole in Aqueous D-Glucose-Amino Acids Model System. J. food. Sci. 81(1):268-274.
Hauser, M. and J.K. Amamcharla. 2016. Novel methods to study the effect of protein content and dissolution temperature on the solubility of milk protein concentrate: Focused beam reflectance and ultrasonic flaw detector-based methods. J. Dairy Sci. 99. 3334-3344.
Hauser, M. and J.K. Amamcharla. 2016. Development of a Method to Characterize High-Protein Diary Powders Using an Ultrasonic Flaw Detector. J. Dairy Sci. 99 (2), 10561064. (Editor's Choice)
Jindal, S., S. Anand, K. Huang, J. Goddard, L. Metzger, and J. K. Amamcharla. 2016. Evaluation of modified surface plate heat exchanger targeted to reduce biofilm formation by common milk spore formers. J. Dairy Sci. 99: 9502-9513. (Editor's Choice)
Kane, D., Getty, K., Mayer, B., and Mazzotta, A. 2016. Sanitizing in dry-processing environments using isopropyl alcohol quaternary ammonium formula. J. Food Protect. 79:112-116. Doi:10.4315/0362-028X.JFP-15-257.
Kyle, C. and J. K. Amamcharla. 2016. Value Addition of Greek Yogurt Whey Using Magnetic Fluid and Sepiolite Treatments. Food and Bioprocess Tech. 9: 553-563.
Lopez, K., Phalen, K., Vahl,C.I., Roberts, K.R., and Getty, K.J.K.. 2016. Investigation of handling practices for fresh produce and the efficacy of commercially available produce washes on removal of pathogens and natural microflora on whole cantaloupe surfaces. Food Control. 68:251-259. Available at: http://dx.doi.org/10.1016/j.foodcont.2016.03.050
Pandalaneni, K. and J.K. Amamcharla. 2016. Focused Beam Reflectance Measurement (FBRM) as a Tool for in situ Monitoring of Lactose Crystallization Process. J. Dairy Sci. 99: 52445253. (Editor's Choice)
Sevart, N.J., N. Baumann, H. Thippareddi, T.A. Houser, J.B. Luchansky, A.C.S. Porto-Fett, D.B. Marx, G.R. Acuff, and R.K. Phebus. 2016. Evaluating the efficacy of three USDA-approved antimicrobial sprays for reducing Shiga toxin-producing Escherichia coli (STEC) surrogate populations on bob veal carcasses. J. Food Prot. 79:956-962.
|
Progress 10/01/14 to 09/30/15
Outputs
Target Audience:Food service personnel, Industry/commodity groups, food processors, regulatory agencies (FDA, FSIS), and consumer groups Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
4(5)-methylimidazole (4-MeI) is a nitrogen-containing heterocyclic compound found in class III and IV ammoniated caramel colors, a group of additives widely used in the food industry. A suspected carcinogen and neurotoxin and efforts are underway to limit its presence in foods. Several methods have been developed to detect and quantitate 4-MeI in different food matrices, including roasted coffee, beer, soft drinks, and soy sauce; however, no methods are available to measure 4-MeI in cooked meat and meat products containing lipids and high levels of interfering nitrogen compounds such as amino acids and peptides. A rapid method using 0.1 M sodium acetate buffer (pH 5) as an extraction solvent followed by derivatization with isobutylchloroformate (IBCF) and gas chromatograph mass-spectrometry (GC-MS) was developed to quantify 4-MeI in cooked meat products with added caramel colors containing 4-MeI. Selected Ion Monitoring mode (SIM) was used to monitor 4-MeI ions fragments. In the eight commercial meat products tested, 4-MeI levels ranged from 0.041-1.015 mg/kg, with recovery of 94.76-103.94%. In addition, a matrix-matched calibration performed by analyzing a spiked cooked meat sample indicated no significant difference (P > 0.05), which means the meat matrix had no effect on the developed method. This method proved useful in analyzing 4-MeI in meat products with added caramel color containing 4-MeI. Four essential Maillard variables (precursors molar concentrations, water amount, sugar type, and sugar amounts) were evaluated to optimize a model system for the study of four HCAs: 2-amino-3-methlimidazo-[4,5-f]quinoline (IQ), 2-amino-3-methylimidazo[4,5-f]quinoxaline (IQx), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-3,4,8-trimethyl-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx). Model systems were dissolved in diethylene glycol, heated at 175 oC for 40 min, and separated using reversed-phase liquid chromatography. To define the model system, precursor amounts (threonine and creatinine) were adjusted in molar increments (0.2/0.2, 0.4/0.4, 0.6/0.6, and 0.8/0.8 mmol) and water amounts by percentage (0, 5, 10, and 15%). Sugars (lactose, glucose, galactose, and fructose) were evaluated in several molar amounts proportional to threonine and creatinine (quarter, half, equi, and double). The precursor levels and amounts of sugar were significantly different (p < 0.05) in regards to total HCA formation, with 0.6/0.6/1.2 mmol producing higher levels. Water concentration and sugar type also had a significant effect (p < 0.05), with 5% water and lactose producing higher total HCA amounts. A model system containing threonine (0.6 mmol), creatinine (0.6 mmol), and glucose (1.2 mmol), with 15% water was determined to be the optimal model system with glucose and 15% water being a better representation of meat systems. High-protein dairy powders are added to a variety of products to improve nutritional, functional, and sensory properties. The powder must be soluble in order to achieve the intended properties. The solubility is effected by processing, storage, and dissolution conditions, as well as the composition of powder. For this study, an ultrasonic flaw detector based method was developed to characterize the solubility of high protein dairy powders. To evaluate the method, commercially available milk protein concentrate (MPC) was obtained and stored at 25°C and 40°C and stored for four weeks to produce powders with different dissolution properties. To test the powders, a 5% (w/w) concentration of powder was added to water. A focused beam reflectance measurement (FBRM) and solubility index were used as a reference method. After powder addition, data was collected at regular intervals for 1800s. The FBRM and solubility index showed that the powders lost solubility as the storage time and temperature increased. From the ultrasound data, one parameter was extracted from the relative velocity and three parameters were extracted from the attenuation data. The ultrasonic flaw detector detected differences in solubility before the solubility index. Overall, the ultrasonic flaw detector based method can characterize the solubility of high-protein dairy powder. Radio frequency dielectric heating of whey protein powders impacted functional properties. When using low-heat and high-heat NDM as samples, RFDH did induce whey protein denaturation, however, the extent was dependent upon the RF conditions. This provides evidence that an alternative processing technology may be considered for the powdered dairy protein industries. Producing products that have multiple uses, may allow for elimination of some ingredients in formulations. This can appeal to consumer seeking "clean labels" on their processed foods. The aim of this research was to validate washing solutions and techniques in reducing pathogens on produce surfaces. Cantaloupes were washed with tap water (TW), 9% vinegar solution, or a commercial antimicrobial containing lactic acid (CA) for 2 min using a washing system. Cantaloupes washed with 9% vinegar solution showed the lowest aerobic plate count (APC) populations after day 1 and 3 of storage. Salmonella spp. or L. monocytogenes inoculated cantaloupes were washed with chemical treatment containing citric acid (CW) or TW. Washing cantaloupes for 120 s with CW showed greater (P<0.05) reductions of Salmonella spp. and L. monocytogenes populations (1.26 and 1.12 log CFU/cm2) than TW (ca. 0.63 log CFU/cm2) on cantaloupe surfaces. Lettuce leaves were inoculated with rifampicin-resistant Escherichia coli surrogates and then washed with CA, 5% vinegar solution or TW for 2 min with agitation (washing system) or without. Log reductions of CA (2.25 log CFU/g) were greater (P=0.015) than those by TW (1.34 log CFU/g), but similar to 5% vinegar solution (2.09 log CFU/g). Overall, incorporation of wash solution or agitation (washing system) in the produce washing process compared to TW alone reduce greater (P<0.05) APC, pathogens, or surrogates populations from lettuce, tomato, and cantaloupe surfaces. All goals of the first round of Education Modules of the STEC Student Training and Education Program (STEC-STEP) were met including posting the work on the project website. A second round of planning and capturing modules is in progress. Results have been communicated to a large number of audiences including scientific, media, government, food handlers, and consumer groups. Specifically, those audiences have received the food safety practices messages resulting from the grant and the messages have been assessed as effective in changing behavior. The STEC-STEP program as well as guidelines, appropriate forms, and evaluation are posted at the website. A call for proposals was issued and 27 projects were approved for interns since the last annual report and 19 students from Minority Serving Institutions (MSI) applied for internships. Dr. Jeff Witte (New Mexico State University) continues to solicit student participants from Minority Serving Institutions. The student poster session at the 2015 STEC CAP Meeting was successful with the 27 interns presenting posters. Overall 25 interns have joined the Frontier Field Trips.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2015
Citation:
Evaluation of Maillard Reaction Variables and Their Effect on Heterocyclic Amine Formation in Chemical Model Systems. 2015. Cara Dennis, Faris Karim, J. Scott Smith. J. Food Science. . 80:T472-T478.
Detection and Quantification of 4(5)-Methylimidazole in Cooked Meat. 2015. Faris Karim, J. Scott Smith. J. Food Science. 80:T465-T471.
Lopez, K., Getty, K. J. K., & Vahl, C.I. 2015. Validation of washing treatments to reduce Escherichia coli O157:H7 and Salmonella spp. on the surface of green leaf lettuce and tomatoes. Food Protection Trends, 35(5), 377-384.
Wei T, Morgan R, Menard, S, Michael M, Schmidt KA. 2015. Radio Frequency Dielectric Heating of Whey Protein Powders Impact Functionality. IFT Annual Meeting of Abstracts (abstract 116-05), July 10- 15, Chicago, IL
Elizabeth Kelly and J. Scott Smith. Inhibition of the heterocyclic amine 2-amino-1-methyl-6-phenylinidazo[4,5-b]pyridine (PhIP) in a closed model system with black pepper extracts. 2015 IFT Annual Meeting, July 10-15, Chicago, Il.
Faris Hussain, Ziyi Linghu, and J. Scott Smith. Formation of 4-methylimidazole in glucose-amino acids model systems. 2015 IFT Annual Meeting, July 10-15, Chicago, Il.
Gengjun Chen, Ron Madl, and J. Scott Smith Inhibitory effect of cereal bran extracts on advanced glycation endproducts in model system. 2015 IFT Annual Meeting, July 10-15, Chicago, Il.
|
Progress 10/01/13 to 09/30/14
Outputs
Target Audience: Food service personnel, Industry/commodity groups, food processors, regulatory agencies (FDA, FSIS), and consumer groups. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Interns continue to be placed with researchers to study microbial detection and elimination as well as interdisciplinary approaches to food safety and security. Interns [N=27] were funded by the USDA CAP grant focused on pathogenic E. Coli. Outputs: The 27 interns were placed, finished their internships, and reported their findings at the annual meeting of the CAP grant. How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Non-Technical Summary This project is a comprehensive approach to address food safety challenges including development of methods for chemical and biological hazard detection; intervention strategies to control those hazards; information transfer of technologies to the scientific community, the federal government, the food industries, and consumers; and related economic, policy, and trade implications. The primary focus of this work will continue methods development for the isolation, detection, and quantification of microbial and chemical hazards and the elimination of those hazards. The research will also resulted in significant information and technology transfer as well as risk assessment, economic, policy, and trade information and will lay the foundation for reaping additional insights in those areas. Furthermore, our food safety work will allowed us to address food security that may be a result of bioterrorism and/or natural disasters. Studies were performed to measure the levels of 2-dodecylcyclobutanone (2-DCB) in chicken jerky treats irradiated at different doses (0 control, 5, 10, 15, and 25 kGy) and soaked in glycerin at different times (0 control, 20 min and 24 h). 2-DCB is a common 2-acylcyclobutanones (2-ACB) found in irradiated muscle containing palmitic acid. Samples were prepared from store bought chicken breast tenderloins, stored in Whirl-Pak bags, and then irradiated with a Cesium-137 source, at 20 °C. Dosimeters were used to verify exposure time for the appropriate absorbed dose. Three replicate experiments were performed. Samples were measured for total fat by the Soxhlet procedure using hexane extraction solvent. Moisture was measured by a microwave gravimetric method. For 2-DCB extraction, a portion sample of ground chicken jerky was mixed with acetonitrile and shaken using a wrist action shaker. The acetonitrile extract was collected and evaporated to dryness using nitrogen and injected into a gas chromatography-mass spectrometer (HP 5890 GC and 5972 detector) fitted with an HP-5MS column operated in the single ion mode monitoring ions mz 98 and 112. The concentration of 2-DCB increased linearly with the doses and had a linear correlation of R2 = 0.9874. The levels of 2-DCB corresponding to the irradiation doses were 0.024 ± 0.003, 0.030± 0.007, 0.033± 0.007, and 0.041 ± 0.008 ppm for 5, 10, 15, and 25 kGy. This study showed that 2-DCB could be used to monitor the absorbed treatment dose and that soaking the chicken in glycerin at different times did not affect the detection of 2-DCB. Heterocyclic amines (HCAs) are highly mutagenic and potentially carcinogenic by-products formed during the Maillard browning reaction, specifically during cooking of muscle-rich foods. Chemical model systems are used to examine the in vitro formation of HCAs while eliminating complex matrices found in meat. Little research has been done on the effects of Maillard reaction parameters on HCA formation. Therefore, in this project, four essential Maillard variables were evaluated to optimize a model system for the study of five HCAs: IQ, MeIQ, IQx, MeIQx, and 4,8-DiMeIQx. Model systems were dissolved in diethylene glycol, heated at 175 oC for 40 minutes, and separated using reversed-phase liquid chromatography (TSKgel ODS-80T, 4.6 mm x 25 cm x 5 µm, column). The Maillard parameters studied were: precursor molar amounts, water concentration, sugar type, and sugar amounts. To define the model system, precursor amounts (threonine and creatinine) were adjusted in molar increments (0.2/0.2, 0.4/0.4, 0.6/0.6 and 0.8/0.8 mmols) and water amounts by percentage (0, 5, 10, and 15%). Sugars (lactose, glucose, galactose, and fructose) were evaluated in several molar amounts proportional to threonine and creatinine (quarter, half, equi, and double). Examined precursor levels and amounts of sugar were significantly different (p<0.05) for total HCA formation, with 0.6/0.6/1.2 mmol producing the highest levels. Water concentration and sugar type had no effect on total HCAs formed in the model system, though 15% water and lactose produced higher total HCA amounts. A model system containing threonine (0.6 mmol), creatinine (0.6 mmol), and glucose (1.2 mmol), with 15% water was determined to be the optimal model system for the five HCAs, with glucose being a better representation of meat systems. Focused Beam Reflectance Measurement as a Tool for in situ monitoring of Lactose Crystallization - Lactose is the most abundant carbohydrate present in milk. It is one of the major ingredients in infant formulations, dried milk, and whey products. Commercial production of lactose involves concentration of whey or whey permeate or milk permeate by evaporation followed by a batch crystallization. Crystallization of lactose was monitored at supersaturated concentrations 50%, 55%, and 60% (w/w) at temperatures 20ºC and 30ºC using an in situ focused beam reflectance measurement (FBRM) system and a refractometer. Chord length distributions obtained from FBRM in the ranges of <50 µm (fine crystals) and 50-300 µm (coarse crystals) were recorded and evaluated in relation to the extent of crystallization and rate constant deduced from the refractometer measurements. The measured fine crystal counts increased with supersaturated concentration and temperature during isothermal crystallization. On the other hand, coarse counts were observed to increase with decreasing supersaturated concentration and temperature. Square weighted chord length distribution obtained from FBRM explains that as concentration increased there was a decrease in chord lengths at 20ºC. The robustness of FBRM in understanding isothermal lactose crystallization at various concentrations and temperatures was successfully evaluated in the study. Overall, FBRM technique shows potential to be a part of process analytical technology to monitor and control of lactose crystallization process. Beverage viscosity could be enhanced by the thermal-induced interactions of whey proteins with casein proteins; however, not to the point that could be used for people suffering from dysphagia. Using the concept of these protein interactions as well as lactalbumin - xanthan gum interaction, beverages were produced that the criteria of nectar-like and could have implications for dysphagia patients. Radio frequency dielectric heating of whey protein powders impacted foaming functionality as well as emulsifying properties when rehydrated. More work needs to be done to determine if this technology can induce alternative functionality in whey protein products, that might contribute to cleaner labels. Producing stable, sufficiently viscous, and nutritious beverages for dysphagia patients could help address a need that would allow a faster recovery rate for those suffering from swallowing disorders. Producing products that have multiple uses, may allow for elimination of some ingredients in formulations. This can appeal to consumer seeking "clean labels" on their processed foods.
Publications
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2014
Citation:
Jianteng Xu, Xiaoyu Su, Soyoung Lim, Jason Griffin, Edward Carey, Benjamin Katz, John Tomich, J. Scott Smith, Weiqun Wang. Characterization and Stability of Anthocyanins in Purple-fleshed Sweet Potato P40. 2014. Food Chemistry. 168 :(in press).
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Kanithaporn Vangnai, Terry A. Houser, Melvin C. Hunt, J. Scott Smith. Effect of Enhancement on the Formation of Heterocyclic Amines in Cooked Pork Loins. 2014. Meat Science 98:88-93.
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Gengjun Chen, J. Scott Smith. Determination of Advanced Glycation Endproducts in Cooked Meat Products. 2014. Food Chemistry. 168:190-195.
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Michael M, Phebus RK, Schmidt KA. 2014. Plant extract enhances the viability of Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus in probiotic nonfat yogurt. Food Sci and Nutr doi: 10.1002/fsn3.189
- Type:
Journal Articles
Status:
Published
Year Published:
2014
Citation:
Michael M, Phebus RK, Thippareddi H, Subbiah J, Birla SL, Schmidt KA. 2014. Validation of radio frequency dielectric heating system for destruction of Cronobacter sakazakii and Salmonella spp. in nonfat dry milk J Dairy Sci 97(12): 7316-24 doi:10.3168/jds.2013-7862
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2014
Citation:
Cara Dennis; J. Scott Smith. Evaluation of Maillard Reaction Variables and Their Effect on Heterocyclic Amine Formation in Chemical Model Systems. 2014 IFT Annual Meeting, June 22-24, New Orleans, LA # 074-03.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2014
Citation:
Gengjun Chen, J. Scott Smith, Ron Madl. Inhibitory effect of cereal bran addition on advanced glycation endproducts in cooked beef patties. 2014 IFT Annual Meeting, June 22-24, New Orleans, LA #074-04.
- Type:
Other
Status:
Published
Year Published:
2014
Citation:
Menard, S, Amamcharla, J, Schmidt, KA. 2014. Electromagnetic Fluid Conditioning Processing Capabilities on the Processing of Skim Milk and the Physical Changes that Occur IFT Annual Meeting of Abstracts (abstract 171-05), June 21-24 New Orleans, LA.
- Type:
Other
Status:
Published
Year Published:
2014
Citation:
Wei, T, Schmidt, KA. 2014. Dairy-based beverage for dysphagia patient prepared by lactalbumin)/lactoglobulin ratio adjustment IFT Annual Meeting of Abstracts (abstract 116-05), June 21- 24 New Orleans, LA
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Progress 01/01/13 to 09/30/13
Outputs
Target Audience: Food service personnel, Industry/commodity groups, food processors, regulatory agencies (FDA, FSIS), and consumer groups Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Interns have been placed with researchers to study microbial detection and elimination as well interdisciplinary approaches to food safety and security. These interns are being funded by the USDA CAP grant focused on pathogenic E. coli. Outputs: To date 20 interns have been placed and finished their internships. Those interns have reported their findings at the annual meeting for the CAP grant. How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Carboxymethyllysine (CML) is a Maillard browning product that can have an inflammatory effect in the body. Spices and their antioxidants may decrease the levels of CML in foods. The purpose of this study was to determine the effect of black pepper, cinnamon, rosemary, onion, and garlic at 0.5%, 1% and 2% levels on CML in quick bread biscuits. Biscuits were baked using each spice and spice level, as well as a control. The data show that CML was significantly inhibited (P<0.05) by all spices at each spice level. Future work could look at the effect of lower levels of spice, or combinations of spices on CML levels. Heterocyclic Amines (HCAs) are a risk factor for human cancers that form in meats cooked at high temperatures. Seven spices were evaluated in this study: black pepper, turmeric, cinnamon, rosemary, thyme, ginger, and oregano. The spices’ ability to inhibit PhIP formation was evaluated in beef patties cooked at 400°C (204°F) for 5 min on each side. Black pepper was studied at 0.25, 0.50, and 1% concentrations while the other spices were evaluated at the 0.25% concentration. Combinations of 0.25% black pepper and 0.25% of each spice were also evaluated. Control patties had a concentration of 2.56 ng/g PhIP content (P<0.05) while in the 0.25% black pepper treated patties, an 81.77% decrease in PhIP was observed. All the spices individually inhibited HCA by 55-82%. Black pepper in combination with turmeric was the best combination, showing a 94.74% inhibition of HCA. Cysteine is considered a conditional amino acid and research has shown that greater cysteine contents (50%) could be sustained in yogurt throughout its shelf life (60 days) by ingredient and process adjustment. This could have health implications for certain sub-populations. Consumer acceptance results showed that consumers had similar overall liking of yogurt with enhanced cysteine to a “conventional-produced product”, when flavored similarly. Beverage viscosity could be enhanced by the thermal-induced interactions of whey proteins with casein proteins. Using the concept of these interactions, beverages that met the criteria of nectar-like and stability were developed that may have applications for dysphagia patients. The main purpose of the study was to determine the efficacy of a tap water and a commercial wash solution for reducing pathogens on the surface of green leaf lettuce, tomatoes, and cantaloupes. Another focus was to develop recommendations on how school food service personnel can improve best practices for washing fresh produce. The commercial wash solution showed to be more effective than cold tap water in reducing Escherichia coli O157:H7 populations on the surface of lettuce and Salmonella spp. on the surface of tomatoes. Both cold tap water and commercial wash solution were minimally effective in reducing Salmonella spp. and Listeria monocytogenes on the surface of cantaloupes to safe levels for consumption. Overall, washing produce with the commercial wash solution was more effective than tap water and should be applied for 2 minutes to reduce the risk of pathogens on the surface of produce. Interns have been placed with researchers to study microbial detection and elimination as well interdisciplinary approaches to food safety and security. These interns are being funded by the USDA CAP grant focused on pathogenic E. coli. Outputs: To date 20 interns have been placed and finished their internships. Those interns have reported their findings at the annual meeting for the CAP grant.
Publications
- Type:
Other
Status:
Accepted
Year Published:
2013
Citation:
Chen, C., M. Michael, R. K. Phebus, H. Thippareddi, J. Subbiah, S. L. Birla and K. A. Schmidt. 2013. Short Communication: Radio frequency dielectric heating of nonfat dry milk affects solubility and whey protein nitrogen index. J. Dairy Sci. 96:1471-1476.
- Type:
Other
Status:
Published
Year Published:
2013
Citation:
Keeping Foods Safe - The Synergistic Role of Black Pepper with other Herbs and Spices for Reduction of Heterocyclic Amine Formation in Grilled Meat. 2013. Symposium - Healthy Eating Made Flavorful, - IFT Meeting 2013 - # 050-02 (Invited presentation).
Hilary Peterson, Phil Ward, J. Scott Smith. The use of non-alkalized cocoa powder as a natural preservative in peanut systems. 2013 IFT Annual Meeting, July 13 - 16, 2013, Chicago Illinois, # 255-141.
Faris Hussain, Scott Smith. Detection and Quantification of 4(5)-Methylimidazole in Cooked Meat. 2013 IFT Annual Meeting, July 13 - 16, 2013, Chicago Illinois, #078-03.
Gengjun Chen, J. Scott Smith. Occurrence of Advanced Glycation Endproducts in Cooked Meat Products. 2013 IFT Annual Meeting, July 13 - 16, 2013, Chicago Illinois, #078-02.
Michael, M., Phebus, R.K., Thippareddi, H., Subbiah, J., Birla, S.L. Schmidt, K.A. Validation of radio frequency dielectric heating (RFDH) system for the destruction of Cronobacter sakazakii and Salmonella spp. in nonfat dry milk. IAFP, July, 2013
Michael, M., Phebus, R.K., Thippareddi, H., Subbiah, J., Birla, S.L. Schmidt, K.A. Thermal inactivation of 5-strain cocktail of Cronobacter sakazakii and Salmonella spp. in nonfat dry milk. IFT, July, 2013.
Bala, S., Schmidt, K.A. Schmidt. Sustaining enhanced cysteine content and gel quality in yogurt during storage IFT, July 2013.
Wei, T., Schmidt, K.A. Heat-induced interactions between casein micelles and whey proteins at varying ?-lactalbumin (?-la) and ?-lactoglobulin (?-lg) ratios. IFT, July 2013. Menard, S., Bala, S., Amamcharla, J., Schmidt, K.A. Preliminary studies on the use of a novel electromagnetic fluid conditioner to modify the functional properties of nonfat yogurt. ADSA, 2013
Bala, S, Schmidt, K.A. 2013. Consumer Acceptance of Cysteine-Enhanced Yogurt Dairy Days. Lopez, K. and Getty, K.J.K., and Vahl, C.I. 2013.Validation of commercial washing treatments to reduce pathogens in green leaf lettuce and tomatoes. Ann. Mtg. International Assoc. Food Protection, Charlotte, NC July 28 31.
Lopez, K. and Getty, K.J.K., and Vahl, C.I. 2013.Validation of commercial washing treatments to reduce pathogens in green leaf lettuce and tomatoes. Ann. Mtg. International Assoc. Food Protection, Charlotte, NC July 28 31.
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Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: The outputs of the project have been disseminated to not only scientific audiences, but to the popular press and government agencies. A poster examining trends in meat recalls was presented at graduate student competition, and later to the Kansas Board of Regents and at a state level conference. A factsheet was prepared and published on the subject of food irradiation, and we are currently collaborating with FDA-CVM on possible toxic effects of irradiation on pet treats. Work has begun on collecting data on plant level interventions to control bacterial pathogens on beef carcasses, and analyzing potential market impacts of plant or firm level trade restrictions. Heterocyclic amines (HCAs), potent mutagens and a risk factor for human cancers, are produced in meats cooked at high temperature. The aim of current studies was to determine the HCA content in cooked meat products (beef, chicken, pork, fish) prepared by various cooking methods (pan frying, oven broiling, and oven baking at 170 to 230 degrees C) that are preferred by U.S. meat consumers. The primary HCAs in these samples were PhIP (2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine), and DiMeIQx (2-amino-3,4,8-trimethyl-imidazo [4,5-f]quinoxaline. Type and content of HCAs in cooked meat samples were highly dependent on cooking conditions. The total HCA content in well-done meat was 3.5 times higher than that of medium-rare meat. Fried pork (13.91 ng/g) had higher levels of total HCAs than fried beef (8.92 ng/g) and fried chicken (7.00 ng/g). Among the samples, fried bacon contained the highest total HCA content (17.59 ng/g). Radio frequency dielectric heating (RFDH) of nonfat dry milk (NDM) impacted whey protein nitrogen index and solubility of NDM, but results were dependent on NDM classification. This technology provided similar lethality treatments as conventional heating and showed that thermal resistance of pathogens was greater in the powdered vs. liquid systems; however, additional work needs to be done on equipment design and optimization to fully understand its impact. As cysteine is considered a conditionally essential amino acid, research results have shown that greater cysteine contents (50%) could be sustained in yogurt throughout its shelf life (60 days) by ingredient and process adjustment. This could have health implications for certain sub-populations. PARTICIPANTS: J. S. Smith, R. Phebus, K. Schmidt, S. Fox, J.D. Ellis, C. Kastner. TARGET AUDIENCES: Food companies, processing industry, governmental agencies and the scientific community. PROJECT MODIFICATIONS: No significant changes.
Impacts
The frequency of meat recalls was found have increased from an average of 19 each year in the 1980s to 68 each year during the 2000s, while the median size of recalls declined from 15,000 lbs in the 1980's to 6,400 lbs in the 2000s. Recall frequency peaked in 2002. Regression analysis indicated that recovery rates for recalls due to E.coli were about 10% lower than those for non bacterial recalls, while those associated with Listeria were about 10% higher. In other work related to food safety, plant level export restrictions were found not to have any significant impacts on US beef prices. Our data that can help food safety professionals recommend cooking methods to be used at home or in the food industry to reduce HCA formation in cooked meat products, will provide important information for use in estimating HCA exposure, and will facilitate investigation of the role of HCAs in the etiology of cancer of population in the United States. Recent research on formation of HCAs in meat products has been shared with major meat producing organizations and with the popular press. The research was also presented at the Institute of Food Technologists annual meetings. This year we have worked to advance the development of Kansas State's Food Systems Window website, a place showcasing all aspects of food systems teaching, research and outreach at KSU. A pilot site has been developed and shared with food systems faculty members. Enhancements and a launch are planned for 2013. We also have continued publishing with a grant team from Iowa State University, determining best ways to train and motivate food service employees to conduct safe food practices on the job. RFDH has the potential to be a post-process lethality treatment for dried NDM, its use in the powdered ingredient industry should be further studied to understand its full potential as a food safety intervention strategy. Consuming yogurt with greater cysteine contents may be a strategy in improving overall health and reducing cataract development. However, further work should be conducted in animal models to verify this theory.
Publications
- Puangsombat, K. P. Gadgil, T. A. Houser , M. C. Hunt and J. S. Smith. 2012. Occurrence of Heterocyclic Amines in Cooked Meat Products. Meat Science 90:739-746.
- Boland, M., and J. Fox. Food Irradiation and Public Health. Food Policy Research Center, University of Minnesota. November 2012.
- Arendt, S.W., Roberts, K.R., Strohbehn, C.H., Ellis, J.D., Paez, P., and Meyer, J. 2012. Use of qualitative research in foodservice organizations: A review of challenges, strategies, and applications. International Journal of Contemporary Hospitality Management 24:1-20.
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