Metabolic Injury to Bacteria at Low Temperatures

Straka, Robert P.; Stokes, J. L.

doi:10.1128/jb.78.2.181-185.1959

Cited by 156 publications

(64 citation statements)

References 14 publications

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“…Different types of organism possess different inherent resistances and susceptibilities to stress. For instance, Gram-negative bacteria are regarded as being more sensitive to cold shock, chilling, and freezing than Gram-positive bacteria (Straka and Stokes 1959). The microbial stress responses that have been selected during evolution include reactions to many of these preservation techniques and result principally in increased resistance to the applied stress.…”

Section: Introductionmentioning

confidence: 99%

Adaptation of Microorganisms to Cold Temperatures, Weak Acid Preservatives, Low pH, and Osmotic Stress: A Review

Beales

2004

Comp Rev Food Sci Food Safe

613

361

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The application of physical stress to microorganisms is the most widely used method to induce cell inactivation and promote food stability. To survive, microorganisms have evolved both physiological and genetic mechanisms to tolerate some extreme physical conditions. This is clearly of significance to the food industry in relation to survival of pathogens or spoilage organisms in food. In some microorganisms, the "cold shock response" has been observed in response to abrupt changes to lower temperatures. This results in the production of specific sets of proteins (cold shock proteins), the continued synthesis of proteins involved in transcription and translation, and the repression of heat shock proteins. The addition of weak acid preservatives (for example, sorbates, benzoates) also induces a specific pattern of gene expression (for example, 'Acid Tolerance Response'), which is likely to be required for optimal adaptation of bacteria to weak acid preservatives and low pH. The primary mode of the antimicrobial action of low pH is to reduce the internal cell pH (pHi) below the normal physiological range tolerated by the cell, leading to growth inhibition. Survival mechanisms involve maintaining pH homeostasis, and this is achieved by a combination of passive and active mechanisms. Microorganisms adapt to osmotic stress by accumulating non-ionic or compatible solutes such as trehalose, glycerol, sucrose, and mannitol. These compatible solutes help balance the osmotic pressure and help preserve protein function inside the cells. By understanding and controlling such mechanisms of adaptation, it may be possible to prevent growth of key microorganisms in food products.2 COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY-Vol. 3, 2004 CRFSFS: Comprehensive Reviews in Food Science and Food Safety organisms will still be metabolically active and viable if transferred to favorable conditions (Busta 1978;Abbiss 1983;Ray 1986). Preservation techniques are designed to prevent microbial growth in processed foods, by disrupting the internal environment of the cell such that growth is no longer possible.Temperature, water activity, addition of preservatives, and pH are all parameters used to inhibit or destroy microorganisms and their spores and are also used as an aid for food preservation (Marechal and others 1999). Other parameters such as heat and bacteriostatic and bactericidal agents are also used in food preservation; they are not included in this review, but have been reviewed extensively (Lindquist 1986;Hendrick and Hartl 1993;Abee and Wouters 1999;Brul and Coote 1999). Some microorganisms have evolved and are capable of rapidly adapting to a continuously changing environment, thus developing tolerance or resistance to increased "doses" of particular stresses. Different types of organism possess different inherent resistances and susceptibilities to stress. For instance, Gram-negative bacteria are regarded as being more sensitive to cold shock, chilling, and freezing than Gram-positive bacteria (Straka ...

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Section: Introductionmentioning

confidence: 99%

Adaptation of Microorganisms to Cold Temperatures, Weak Acid Preservatives, Low pH, and Osmotic Stress: A Review

Beales

2004

Comp Rev Food Sci Food Safe

613

361

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“…Upadhyay and Stokes (1961) observed that elimination of oxygen decreased both rate and extent of growth of facultative psychrophiles, indicating nonlethal metabolic injury. Straka and Stokes (1959) reported that nonlethal metabolic injury caused an increase in nutritional requirements of psychrophilic bacteria. However, for vacuum-packaged samples, the observation that the actual counts on frozendefrosted poultry were at least as great, and sometimes slightly higher, than on freshly refrigerated chicken may be explained by the action described by Mossel and Ingram (1955).…”

Section: Bacterialmentioning

confidence: 99%

Effect of Freezing and Packaging Methods on Survival and Biochemical Activity of Spoilage Organisms on Chicken

Rey

Kraft

1971

Journal of Food Science

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SUMMARY— A study was conducted to determine effects of freezing, thawing, and subsequent holding at about 5°C on survival or growth of aerobic bacteria on chicken packaged with various materials. Production of fluorescent pigment, and extracellular proteinase and lipase activities were used as indices of the ability of the organisms to produce spoilage. Growth of bacteria was determined by colony counts. Assays for proteolysis were made by means of a dye binding method; lipolysis of chicken fat was determined by titration of free fatty acids. Fluorescent pigment formation was evaluated by means of a photofluorometer. The influence of availability of oxygen on proteolytic and lipoytic spoilage of poultry was studied after chicken was packaged with materials having high or low oxygen permeability and by vacuum packaging. Fluorescent pigment production, proteofytic and lipolytic spoilage of chicken stored at 5°C was directly related to the availability of oxygen provided by the packaging procedure. Bacterial numbers paralleled increases in biochemical indices of deterioration. Freezing of chicken at −29°C for 35 days followed by defrosting and refrigerated storage increased the proportion of biochemically active psychrophiles on the surface of the meat. Vacuum packaging generally limited amount of spoilage as measured by the criteria specified. When samples were analyzed after alternate freezing and thawing, total aerobic bacterial counts were only slightly different from those on chicken frozen continuously for 22‐25 days.

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“…The production of pyoverdine declined faster than did cell numbers. Nonlethal metabolic injury to several species of Pseudomonas at sub-zero temperatures has been demonstrated by Straka et al ( 1959). Apparently, freezing may affect the constitutive enzyme forming systems in some cells of the same organism, resulting in death, while other cells may be affected only in their adaptative enzyme forming systems, and remain capable of surviving frozen conditions.…”

Section: Effect Of Temperatures Below Freezing On Survival and Biochementioning

confidence: 99%

Influence of Temperature on Some Biochemical Characteristics of Pseudomonas Associated with Spoilage of Chicken

Rey

Kraft

Seals

et al. 1969

Journal of Food Science

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SUMMARY Studies were conducted with four cultures of Pseudomonas isolated from frozen chicken. The effect of temperature on some biochemical activities of the organisms was evaluated and the individual response of the cultures to temperature was determined. Growth, survival and production of the green fluorescent pigment, pyoverdine, and extra‐cellular proteinase and lipase activities were used as indices of the ability of pseudomonads to produce spoilage. The four isolates differed in their ability to perform the metabolic functions mentioned. The cultures were incubated at 15°, 5°, −18°, and −29°C. Assays for proteolysis were made by means of a dye binding method; lipolysis was determined by titration of free fatty acids released from chicken fat, and a photo‐fluorometer was used to measure fluorescent pigment. Growth was determined by colony count. At temperatures above 0°C, survival was better and growth and enzyme activity were more extensive at 5° than at 15°C. Proteinase activity increased continuously, even when viable cells were decreasing; lipase production was correlated with growth. Formation of pyoverdine declined faster than did cell numbers. Survival of the cultures was better at −18° than at −29°C, Impairment of pyoverdine secretion was observed after exposure of the organisms to freezing temperatures, but the activity of the extracellular enzymes was not affected at temperatures below 0°C. No marked differences were observed among cultures in rate of cell division, but maximum populations, survival of organisms and stability of the proteolytic, lipolytic and fluorescent activities of the isolates were inversely related to biochemical activity above 0°C.

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Metabolic Injury to Bacteria at Low Temperatures

Cited by 156 publications

References 14 publications

Adaptation of Microorganisms to Cold Temperatures, Weak Acid Preservatives, Low pH, and Osmotic Stress: A Review

Adaptation of Microorganisms to Cold Temperatures, Weak Acid Preservatives, Low pH, and Osmotic Stress: A Review

Effect of Freezing and Packaging Methods on Survival and Biochemical Activity of Spoilage Organisms on Chicken

Influence of Temperature on Some Biochemical Characteristics of Pseudomonas Associated with Spoilage of Chicken

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