Microbiological Survey of Tofu Sold in a Rural Illinois County

1999 ◽  
Vol 62 (9) ◽  
pp. 1050-1053 ◽  
Author(s):  
HEA-RAN ASHRAF ◽  
MARY WHITE ◽  
BRIAN KLUBEK
Keyword(s):  
Methylene Blue ◽  
North America ◽  
Analysis Of Variance ◽  
Food Product ◽  
Coliform Bacteria ◽  
Aerobic Bacteria ◽  
Grocery Stores ◽  
Bacterial Counts ◽  
Acceptable Range ◽  
Microbial Status

The purpose of this study was to determine the microbial status of tofu sold in a rural Illinois county and assess the factors contributing to the safety of tofu. Six brands of tofu from eight different stores (60 total samples) were purchased and analyzed for temperature, pH, total aerobic bacteria, and the presence of coliforms. Relationships between age, temperature, pH of tofu, and total aerobic bacteria were tested. An analysis of variance was also performed to test for differences in total bacterial counts among the brands. Mean aerobic bacterial counts ranged from 0 to 7.76 × 107 CFU/g. Fifty-five percent of the tofu tested fell within the excellent range for freshness as delineated by the standards developed by the Soyfoods Association of North America, 6.7% fell within the acceptable range, 6.7% within the marginal range, and 28% within the unacceptable range. Sixteen percent of the samples contained coliform bacteria. No significant correlation was found between variables, except pH with total aerobic bacterial counts (r = −0.51) and pH with eosin-methylene blue agar counts (r = −0.67). Most of the tofu was displayed at unsafe temperatures (>5°C) for potentially hazardous foods. This study confirmed the concerns regarding safety of tofu sold in the grocery stores. Based on these results, special training on tofu storage and handling is recommended for grocery stores selling this food product.

scholarly journals Microbial Load on Paper/Polymer Currency and Coins

1970 ◽  
Vol 9 ◽  
pp. 105-109 ◽  
Author(s):  
Tista Prasai ◽  
Kayo Devi Yami ◽  
Dev Raj Joshi
Keyword(s):  
Key Words ◽  
Heterotrophic Bacteria ◽  
Science And Technology ◽  
Microbial Load ◽  
Disease Spread ◽  
Coliform Bacteria ◽  
Aerobic Bacteria ◽  
Contamination Level

Currency notes and coins serve as an agency of transmission of microorganisms since they are passed freely from hand to hand as a medium of exchange. A research, with an objective to explore the microbial load on Nepalese paper/ polymer currency notes and coins, was carried out at the Environment Laboratory of Nepal Academy of Science and Technology, Khumaltar from November 2006 to May 2007. All together 63 samples of paper/polymer notes and coins from different professionals of different places at Kathmandu were collected and analyzed for the presence of microorganisms. Among the total tested paper/ polymer and coin samples, 98.4% were found to have heterotrophic aerobic bacteria, 87.3% were contaminated with coliform bacteria and 79.4% showed presence of Staphylococci. Contamination level was found in increasing order of coins> polymer notes>paper notes. The presence of high microbial load on currency notes and coins indicate the potentials of such currencies for possible disease spread in the human communities. Key words: currency notes; coins; heterotrophic bacteria; Coliform bacteria; Staphylococci DOI: 10.3126/njst.v9i0.3173 Nepal Journal of Science and Technology 9 (2008) 105-109

scholarly journals Bromatological and Microbiological Characterization of Andean Tubers Mashwa (Tropaeolum Tuberosum) and Oca (Oxalis Tuberosa)

2021 ◽  
Author(s):  
Cristian José Esparza Bonilla ◽  
Cesar Iván ◽  
Flores Mancheno ◽  
Tatiana Elizabeth Sánchez Herrera
Keyword(s):  
Factor Analysis ◽  
Analysis Of Variance ◽  
Aerobic Bacteria ◽  
Oxalis Tuberosa ◽  
Tropaeolum Tuberosum

The objective of this research was to analyze the bromatological and microbiological composition of Andean tubers, to determine whether their state of maturation influences their composition. Mashwa (Tropaeolum tuberosum) and oca (Oxalis tuberosa) tubers were analyzed. Different degrees of maturation (tender, ripe) were considered. In each analysis, three treatments were carried out, using 100g of sample. The data were analyzed through a two-factor analysis of variance with several samples per group. The average values obtained from the bromatological data of tender mashwa were: 12.33% protein, 0.87% fat, 5.17% ash and 6.41% moisture. The values for mature mashwa were: 15.27% protein, 1.00% fat, 6.74% ash and 5.85% moisture. For tender oca, the values were: 7.47% protein, 0.65% fat, 4.59% ash and 7.03% moisture. Finally, the values for mature oca were 8.92% protein, 0.64% fat, 5.40% ash and 6.03% moisture. In terms of the microbiological evaluation, a minimal presence of the following aerobic bacteria was observed: Stapylococus aureos, coliforms, Eschericha coli. The results showed that the microbiological values ​​for Andean tubers (mashwa and oca) were within the safe parameters, so the tubers are suitable for consumption. Keywords: bromatological, microbiological, Tropaeolum tuberosum, Oxalis tuberosa, maturation. RESUMEN El objetivo de esta investigación fue analizar la composición bromatológica, microbiológica, y determinar si el estado de maduración influye en la composición de los tubérculos andinos. Los tubérculos analizados, mashwa (Tropaeolum tuberosum) y oca (Oxalis tuberosa), donde se considero diferentes grados de maduración (tierno, maduro), en cada análisis se empleo 3 tratamientos utilizando 100g de muestra. Los datos fueron analizados mediante el programa Excel con un análisis de varianza de dos factores con varias muestras por grupo. El promedio obtenido en los datos bromatológicos de mashwa tierna son: proteína de 12,33%, grasa 0,87%, ceniza 5,17% y humedad 6,41%, mashwa madura 15,27% de proteína, 1,00% de grasa, 6,74% de ceniza y 5,85% de humedad, para la oca tierna en proteína de 7,47%, grasa 0,65%, ceniza 4,59% y humedad 7,03%, oca madura son de 8,92% de proteína, 0,64% de grasa, 5,40% de ceniza y 6,03% de humedad. En el caso de la evaluación microbiológica se observó la presencia mínima de Bacterias Aerobias, Stapylococus Áureos, Coliformes, Eschericha Coli. Determinando que los valores microbiológicos para los tubérculos andinos (mashwa, oca) se encuentran dentro de los parámetros por lo que están libres de patógenos y son aptos para el consumo. Palabras claves: bromatológico, microbiológico, Tropaeolum tuberosum, Oxalis tuberosa, maduración.

Potato-Like Odor of Retail Beef Cuts Associated with Species of Pseudomonas

1986 ◽  
Vol 49 (4) ◽  
pp. 272-273 ◽  
Author(s):  
R. L. DAISE ◽  
E. A. ZOTTOLA ◽  
R. J. EPLEY
Keyword(s):  
Coliform Bacteria ◽  
Plate Count ◽  
Aerobic Bacteria ◽  
Gram Negative ◽  
Consumer Complaints ◽  
Psychrotrophic Bacteria ◽  
Plate Count Agar ◽  
Litmus Milk ◽  
Musty Odor ◽  
Retail Cuts

Retail cuts of beef and hamburger packages from a North Dakota meat processor were examined due to consumer complaints of a strong potato-like or musty odor associated with the meat. Examination for total numbers of aerobic bacteria on plate count agar and for gram-negative psychrotrophic bacteria on crystal violet tetrazolium agar revealed numbers in excess of 108 CFU/g. Numbers of coliform bacteria on violet red bile agar were in excess of 106 CFU/g. Gram-negative rods were isolated and identified. The isolates were characterized by a positive catalase reaction, oxidase production, an oxidative O/F reaction, nonutilization of lactose, liquefication of nutrient gelatin, slight motility, production of acid in litmus milk with decoloration and clotting, nonproduction of indole, and nonreduction of nitrate. The isolate was tentatively identified as a Pseudomonas of undetermined species, probably a variant of either Pseudomonas taetrolens or Pseudomonas perolens.

A Training Course on Food Hygiene for Butchers: Measuring Its Effectiveness through Microbiological Analysis and the Use of an Inspection Checklist

2005 ◽  
Vol 68 (11) ◽  
pp. 2439-2442 ◽  
Author(s):  
MARIA LUIZA SANTOMAURO VAZ ◽  
NEIL FERREIRA NOVO ◽  
DIRCE MARIA SIGULEM ◽  
TANIA BENINGA MORAIS
Keyword(s):  
Food Safety ◽  
Storage Conditions ◽  
Coliform Bacteria ◽  
Microbiological Analysis ◽  
Food Hygiene ◽  
Flow Process ◽  
Safety Practices ◽  
Bacterial Counts ◽  
Training Course ◽  
Safety Procedures

The effectiveness of food hygiene training for a group of retail butchers was evaluated with the aim of verifying whether the butchers modified their behavior in the light of knowledge gained and whether their acquired knowledge or behavior change was sustained over a period of time. Microbiological analysis (enumeration of mesophilic and coliform bacteria and Escherichia coli) of a raw semiprocessed product (stuffed rolled beef) was conducted, and an inspection checklist was issued before the training course (T0). Initial results were later compared with results obtained 1 month (T1) and 6 months (T6) after the training. The checklist comprised 89 items classified into five categories: A, approved suppliers and product reception; B, storage conditions and temperature control; C, flow process, food handling procedures, and conditions of the window display unit; D, facility design and proper cleaning and sanitizing of equipment, utensils, and work surfaces; and E, pest control system, water supply control, and garbage disposal. The inspection results were recorded as “yes” or “no” for each item. Compliance with food safety procedures was recorded as the percentage of “yes” answers. The bacterial counts were significantly higher at T0. At T6, there was no significant increase in bacterial counts. There was a significant improvement in food safety practices at T1 and T6 compared with T0 for all categories. When comparing T0 and T1, the largest increases in the compliance scores were seen within categories C and D. No significant decrease in scores for compliance with food safety practices was observed at T6. Supervision and refresher activities may be necessary to maintain behavioral changes for a longer period of time.

A COMPARISON OF SIX METHODS OF PREPARING AND USING THE METHYLENE BLUE STAIN FOR BACTERIAL COUNTS BY THE DIRECT MICROSCOPIC METHOD*

1954 ◽  
Vol 17 (6) ◽  
pp. 179-184 ◽  
Author(s):  
Nathan Mantel ◽  
A. H. Robertson
Keyword(s):  
Methylene Blue ◽  
Federal State ◽  
Cooperative Study ◽  
Microscopic Method ◽  
Bacterial Counts ◽  
Blue Stain ◽  
Microscopic Count

A cooperative study, involving 12 federal, state, local, and private laboratories throughout the country, was conducted to evaluate six methods of preparing and using the methylene blue stain for the direct microscopic count of bacteria in milk. Three of the six methods were found superior, yielding significantly higher bacteria counts, at the same time providing greater ease in counting. These three methods are: Levine and Black's acid-and-water-free stain; North's aniline oil stain; and Anderson's polychrome stain.

scholarly journals Isolation of Food-Borne Microorganisms from Atlantic Mackerel and Disinfection of the Raw Fish by Radiation, Low Temperature and Combination Treatments

1970 ◽  
Vol 25 (2) ◽  
pp. 105-109
Author(s):  
Manik Hossain ◽  
M Kamruzzaman Munshi ◽  
Rasheda Yasmin Shilpi ◽  
Harun Or-Rashid
Keyword(s):  
Low Temperature ◽  
Frozen Storage ◽  
Bacterial Count ◽  
Total Coliform ◽  
Faecal Coliform ◽  
Coliform Bacteria ◽  
Isolation And Identification ◽  
Bacterial Counts ◽  
Coliform Count ◽  
Combination Treatments

An investigation was undertaken for the isolation and identification of fish-borne microorganisms from mackerel fish (Scomberomorus guttatus) collected from Savar Bazar. Radiation, low temperature (-20°C) and combination treatments were then applied for the decontamination of associated organisms. The ranges of total viable bacterial count, total coliform count, total faecal coliform count and total staphylococcal count varied from 6.5 x 104 to 1.04 x 105, 2 x 102 to 4.0 x 102, 0 to 1 x 102 and 4.4 x 104 to 3.8 x 104 cfu/g respectively, while the total fungal count was nil. Sixty-four bacterial isolates were identified including Staphylococcus (19%), Micrococcus (11%), Enterobacter (8%), Klebsiella (17%), Bacillus (19%), Escherichia (17%) and Pseudomonas (9%). To disinfect the microorganisms, the samples were irradiated at different doses (0-10.0 kGy) of gamma irradiation. Total coliform and total faecal coliform bacteria were inactivated below the detectable level at 2.5 kGy of irradiation. The number of total viable bacteria decreased by three logs when irradiated at 5.0 kGy and the number of Staphylococcus bacteria were eliminated completely after the irradiation dose of 5.0 kGy. During frozen storage, the total viable bacterial counts were gradually declined in all the samples. After six months of storage the bacterial counts were decreased about one log in all of the samples. It has been observed that combination treatments (irradiation and freezing) are more effective than the single treatment for eliminating the fish-borne bacteria. Keywords: Mackerel fish; Microbial contamination; Irradiation; Low temperatureDOI: http://dx.doi.org/10.3329/bjm.v25i2.4871 Bangladesh J Microbiol, Volume 25, Number 2, December 2008, pp 105-109

RAPID CALCULATION OF LOGARITHMIC AVERAGE BACTERIAL COUNTS OF MILK

1956 ◽  
Vol 19 (11) ◽  
pp. 319-322
Author(s):  
John C. Schilling
Keyword(s):  
Methylene Blue ◽  
Plate Count ◽  
Slide Rule ◽  
Bacterial Counts ◽  
Bulk Milk ◽  
Logarithmic Average ◽  
Rule Type ◽  
Rapid Calculation ◽  
Methylene Blue Test

Determination of logarithmic averages of bacterial counts is a necessary and laborious task in grading raw and pasteurized milk. As the plate count determination replaces the methylene blue test for the ever increasing number of bulk milk producers, the problem becomes greater. A slide rule type of device has been developed that may materially simplify this task. This method is explained with information relative to its principle, application, accuracy, and advantages.

EFFECT OF PASTEURIZATION ON THE DIRECT MICROSCOPIC COUNT OF EGGS

1971 ◽  
Vol 34 (4) ◽  
pp. 209-211 ◽  
Author(s):  
H. E. Hall ◽  
D. F. Brown ◽  
R. B. Read
Keyword(s):  
Methylene Blue ◽  
Bacterial Count ◽  
Bacterial Cells ◽  
Bacterial Counts ◽  
The North ◽  
Counting Chamber ◽  
Blue Stain ◽  
Microscopic Count ◽  
Whole Egg

When pasteurized whole eggs from breakers were examined by the Direct Microscopic Count (DMC) procedure, the bacterial count frequently appeared to be too low to correlate with the observed state of decomposition. The DMC of whole egg was found to decrease during pasteurization. To determine why, DMC's were done using the North Aniline Oil - Methylene Blue Stain and the Levowitz-Weber modification of the Newman-Lampert stain. Total bacterial counts also were made using the Petroff-Hausser counting chamber. Results indicated that the reduction in count resulted from lysis of some of the bacterial cells in egg rather than to loss of stainability. Crystalline lysozyme at the concentration found in egg and whole egg preparations produced similar reductions in the DMC of bacteria isolated from egg.

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