Statistical analysis. During a period of about a year, a total of 178 samples (76 from beef, 89 from pork, and 13 from chicken) were obtained from raw materials (21.3%) and final products (78.7%). Zoo Biol 31:574-585, 2012. 3. By season, the highest CC was obtained in summer, followed by autumn and then spring (p>0.001). In this review, we’ll look at significance testing, using mostly the t-test as a guide.As you read educational research, you’ll encounter t-test and ANOVA statistics frequently.Part I reviews the basics of significance testing as related to the null hypothesis and p values. The objective of this study was to compare recovery of microorganisms for various beef samples and beef contact surfaces using conventional pour plating techniques and Petrifilm methods. XPS analysis also revealed differences in the surface element compositions of the biofilm cells. Where µ 1 and µ 2 are the sample means, SD 1 and SD 2 are the corresponding sample standard deviations, and n 1 and n 2 are the corresponding sample sizes. Pearson’s Correlation Coefficient 2.2. American Public, ... A variation of the swabbing method is to use Petrifilm, known for its ease of use and rapidity of bacterial counting. Mean log10 counts on PSM were 5.86 compared to 6.11 on SMA (P<0.01) or a mean log10 difference of −0.25. These analyses indicate that the Petrifilm SM method would be a possible alternative for the aerobic plate count method. There was no apparent correlation between spore recovery and the nature of the coupon material, i.e., porous or nonporous. Events that may result in cross-contamination include inadequate hygiene practices, contaminated equipment surfaces, contamination via food handling personnel, further product processing, or storage abuse All of these niches require consistent environmental surveillance systems to monitor microbial harborage sites to prevent foodborne illnesses via cross-contamination. Blue crab (Callinectes sapidus) samples were collected from commercial processing plants in Louisiana and examined for microbiological quality. ments). The results of evaluating food-contact surfaces using Petrifilm are similar to those found by plate count for counting mesophilic aerobic bacteria. In addition, there was a positive correlation between the APC and CC (r=0.261). The surfaces of the fruit and vegetables section were the most contaminated, followed by the sections for cured meats and cheeses, fresh seafood, the aisles of the sections tested, meat, and yogurts and desserts. SPSS reports the mean and standard deviation of the difference scores for each pair of variables. These results suggested that the 3M Petrifilm plate method could replace the conventional methods in the analysis of microorganism contamination measurement in meat products. Structural basis and mechanism of enoyl reductase inhibition by triclosan. Evaluation of the skin disinfecting activity and cumulative effect of chlorhexidine and triclosan handwash preparations on hands artificially contaminated with Serratia marcescens. P value 1986. Ergebnisse bei Lebensmitteln pflanzlichen sowie gemischten (pflanzlichen und tierischen) Ursprungs, Comparison of the Real‐time Microrespirometer and Aerobic Plate Count Methods for Determination of Microbial Quality in Ground Beef, Bacteriologic and Nutritional Evaluation of a Commercial Raw Meat Diet as Part of a Raw Meat Safety Program, Comparison of Bacterial Swab Samples Given Different Storage Treatments, Comparison of a Dry Medium Culture Plate (Petrifilm SM Plates) Method to the Aerobic Plate Count Method for Enumeration of Mesophilic Aerobic Colony-Forming Units in Fresh Ground Beef, Enumeration of Aerobic Plate Count and E. coli During Blue Crab Processing by Standard Methods, Petrifilm™, and Redigel™, Compendium of methods for the microbial examination of foods, Indicator organisms in meat and poultry products, Comparison of Redigel, Petrifilm, Spiral Plate System, Isogrid, and Aerobic Plate Count for Determining the Numbers of Aerobic Bacteria in Selected Foods, Pathogen Reduction and Hazard Analysis and Critical Control Point (HACCP) systems for meat and poultry. Comparison of recoveries for microorganisms from fresh and frozen beef using a pour plate method and Petrifilm for aerobic plate count, coliform count, All figure content in this area was uploaded by Peter M Muriana, beef cuts, boxed beef, and ground beef samples. A comparison between neutralizing buffer and letheen broth for recovery of surface microorganisms was done for both the APC pour plating method and APC Petrifilm. Common applications of the paired sample t-test include case-control studies or repeated-measures designs. were taken from beef carcasses, boxed beef, and ground beef. Cells entrapped in biofilms formed in the presence of subinhibitory concentrations of dicloxacillin had significantly lower (P < 0.05, as determined by a paired t test) water contact angles, reflecting a decrease in hydrophobicity . By month, APC levels were the highest in September and the lowest in February (p>0.001). The same was observed for S. epidermidis with tetracycline but not for S. haemolyticus since cells in biofilms or planktonic cultures had significantly different susceptibilities. Individual data points are shown, with means and SEM indicated by horizontal lines; n = 13, *P < 0.05, significantly different as indicated; two‐tailed paired t‐test. The null hypothesis assumes that the true mean difference between the paired samples is zero. Typically, a paired t-test determines whether the paired differences are significantly different from zero. Hangug chugsan sigpum haghoeji = Korean journal for food science of animal resources. Performs unpaired t test, Weldh's t test (doesn't assume equal variances) and paired t test. *Indicates values that are not significantly different (P > 0.05, paired t-test). Several types of t-tests exist for different situations, but they all use a test statistic that follows a t-distribution under the null hypothesis: The paired T test (3) was used to determine whether differences in the mean colonysize andcolonycountsfor the different media werestatistically significant. The most important factor contributing to source and level of microbial contamination for ground beef and retail cuts was from incoming raw materials obtained from different suppliers of beef. Median magnesium, potassium, and sodium concentrations conformed to the approximate nutrient content. Clear results with links to extensive explanations. T-test and Analysis of Variance abbreviated as ANOVA, are two parametric statistical techniques used to test the hypothesis. Escherichia coli and total coliform bacteria were quantified using a ready-made culture medium system. Changes were considered significant at the p < 0.05 = *, p < 0.01=**, and p < 0.001 = *** level. (B) The expression of HDACs normalized to GAPDH in HCT15 and HT29 cells after treatment with 1 μΜ TSA for 24 h, Data shown are means ± SEM. BBL™ Trypticase™ Soy Agar (TSA) with Lecithin and Polysorbate 80 sterile pack plates are used for the detection and enumeration of microorganisms present on surfaces of sanitary importance. Minimizing the possibility of formula variability, the standardized … Total colony-forming units were determined in 119 fresh ground beef samples (29 extra-lean, 30 lean and 60 regular) purchased at nine different retail markets over a period of 6 wk. Paired Samples t-test: Example. The Petrifilm plate method was simpler and less time-consuming in sample preparation and, in procedures, faster than the conventional method. All samples were plated on aerobic plate count Petrifilm (for APC) andE. Environmental surveillance is achieved through routine surface sampling of the food contact surfaces and surrounding areas. Individual data points are shown, with means and SEM indicated by horizontal lines; n = 13, *P < 0.05, significantly different as indicated; two‐tailed paired t ‐test. Spearman’s Rank Correlation 2.3. Likewise, significantly higher microbiological counts were observed on painted wood than on stainless steel, plastic, and painted epoxy surfaces (p < 0.05). A large study was designed to determine the relationship of these two methods and the root cause for the deviations. This is the first report of the role of B. amyloliquefaciens in the liquefaction of Petrifilm plates and its negative impact on accuracy. At a >95% significance level, a paired t test showed statistically significant spore recoveries from all except carpet-wallboard, cinder block-wallboard, cinder block-wood, cinder block-steel, and steel-wood. Paired t test results suggested that the Petrifilm AC method produced significantly different results compared with standard APC. Because it is convenient and gave comparative results, Petrifilm offers a good alternative for environmental microbial testing and red meat product testing. The density of sucrose in TSA varied from 10% to 50%. Semantic Scholar is a free, AI-powered research tool for scientific literature, based at the Allen Institute for AI. Comparison of the antibacterial efficacy of 4% chlorhexidine gluconate and 1% triclosan handwash products in an acute clinical ward. The 3M Petrifilm LAB Count Plates have recently been launched as a time-saving and simple-to-use plate designed for detecting and quantifying LAB. Results and Discussion T ABLE 1 SUMMARIZESTHE EFFECTSOF washing and storage on survival populations of attached S. … Reduction of Bacterial Populations on Beef Heads and Tongues. Isolates were subjected to ... compared using paired t-test. 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