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C A Genigeorgis

Publications and source records attributed to C A Genigeorgis.

10 recordsLinked to original sources
PubMed1993

Modeling lag phase of nonproteolytic Clostridium botulinum toxigenesis in cooked turkey and chicken breast as affected by temperature, sodium lactate, sodium chloride and spore inoculum.

The length of the lag phase (LP) of toxigenesis in commercially cooked turkey meat stored under vacuum was determined as affected by 0, 1.2, 2 and 3% sodium lactate (L), 0, 1 and 2% NaCl (S), spore (pool of nonproteolytic B and E strains: B2, B17, B197, B706, E211, E250, E KA-2 and E Beluga) inoculum (I) of 10(-2) to 10(4), storage temperature (T) of 4, 8, 12, 16, 20 and 30 degrees C and their interactions. The time from inoculation to the detection of first toxic sample was defined as LP. Using regression analysis the following model predictive of LP of C. botulinum toxigenesis in the cooked turkey breast was derived: Log(1/LP) = -2.2877 -0.1235(S) -0.2174(L) +0.4391(square root of T) +0.0204(square root of T) (I). The model explained 94.5% of the variation in results, in which square root of T was the most influential factor (65%), followed by L (21.2%), interaction of I and square root of T (4.9%) and S (3.4%). The model predicted LPs longer than those observed in 28.3% of the comparisons, but only in 1% of the comparisons when the lower limit of the 90% confidence interval of LP was used. Similar trends on the effect of L on C. botulinum were observed in an inoculated chicken meat study. This study demonstrated quantitatively that increasing L and S concentrations and lowering of T had a beneficial effect on delaying toxigenesis.

Analysis of Variance↗
PubMed1989

Present state of knowledge on staphylococcal intoxication.

Globally, staphylococcal intoxication remains a very common food poisoning. In this review, emphasis is being placed on epidemiological aspects of the problem and the effect of food environment on the survival and growth of staphylococci and production of enterotoxins. The high prevalence of staphylococci in raw foods of animal origin requires effective processing for safety. Man remains a major reservoir for post-process recontamination. The effect of the intrinsic characteristics of foods (pH, water activity, Eh, preservatives competing microbial flora, natural food) and extrinsic parameters of processing and storage (temperature, freezing, irradiation, dehydration, packaging, humidity) on staphylococcal survival, growth and enterotoxin production has been evaluated extensively. While staphylococci can be destroyed easily the enterotoxins can survive practically all food processing. While extreme levels of intrinsic variables can control enterotoxin production, yet the environment of most foods is conductive to staphylococcal growth. Rapid food cooling, refrigeration and consumer, food handler and processor education remain the key to staphylococcal food poisoning prevention.

Animals↗
PubMed1983

Prevalence of Campylobacter jejuni in two California chicken processing plants.

Two federally inspected California chicken processing plants participated in Campylobacter jejuni prevalence studies. Twelve sampling sites were included in each of four groups. Groups were based on bird age, scald water temperature, and plant sampled. Scald water temperatures of 60 degrees C (140 degrees F) did not contribute to a lower prevalence of C. jejuni in edible parts, as did temperatures of 53 degrees C (127 degrees F) and 49 degrees C (120 degrees F). The feather picker and chilling tank were areas of major cross-contamination. C. jejuni was isolated from 68% of the ready-for-market products. The organism was recovered from 60 to 100% of the ceca in the four groups, and some numbers in the fecal material exceeded 10(6)/g. The level of C. jejuni in intestinal tracts seemed to correlate with the presence of the organism in the edible parts.

Abattoirs↗
PubMed1983

Prevalence of Campylobacter jejuni in chicken wings.

Campylobacter jejuni was found in 82.9% of 94 chicken wing packages analyzed on the day of arrival at supermarkets and in 15.5% of 45 packages obtained from the supermarket shelves a few days later. The number of bacterial cells ranged from 10(2) to 10(3.9) per wing. The prevalence of C. jejuni in the wings varied with the brand, the day of sampling, and the age of the product.

Animals↗
PubMed1975

Deoxyribonucleic acid base composition and biochemical properties of certain coagulase-negative enterotoxigenic cocci.

Eight coagulase-negative, enterotoxigenic strains of cocci and one weakly coagulase-positive strain isolated from a number of different sources, including cases of food poisoning incidents, were evaluated for their relationship to Staphylococcus aureus on the basis of deoxyribonucleic acid (DNA) buoyant density and physiological studies. One strain of cocci produced enterotoxins A and C, two strains produced types B and C, four strains produced only type C, and one strain only type D. The enterotoxin produced by one strain of cocci was serologically untypable. None of the test organisms produced detectable amounts of enterotoxin in broth cultures. The test strains of cocci exhibited the following profile: all produced catalase; all grew anaerobically and fermented glucse; five were sensitive to lysostaphin; the percentage of guanine plus cytosine content of their DNA varied from 32.7 to 37.6; five produced acid from mannitol both aerobically and anaerobically; two formed delta-hemolysin; five produced phosphatase and acetoin; and all produced heat-stable nuclease. None of the organisms exhibited typical characteristics of S. aureus, S. epidermidis, or S. saprophyticus. On the basis of the present data and data reported elsewhere, these organisms should be considered as variants or mutants of S. aureus.

Aerobiosis↗