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Shelf-life of coleslaw made from cabbage treated with gaseous acetic acid
Abstract
Coleslaw containing 25% mayonnaise was formulated with untreated cabbage (control) and cabbage fumigated with two levels of gaseous acetic acid: 0.08 mL and 0.50 mL/100 g cabbage. A device consisting of a rotating barrel and vaporizing chamber was used to fumigate the shredded cabbage. Populations of aerobic microorganisms in coleslaw made from untreated cabbage reached 108 cfu/g after 15 days in storage at 5C. Growth of lactic acid bacteria was extensive and in some cases this group was chiefly responsible for spoilage. Microorganisms were not detected in coleslaw made from cabbage fumigated at higher levels of acetic acid during 22 days in storage. Mayonnaise had a lethal effect on the microflora of cabbage, and fumigation with acetic acid prior to formulation of coleslaw increased the effect. The color of coleslaw was not affected by fumigation but CO2 production during storage was reduced.
... In addition to conventional methods of application of chemical treatments (i.e., immersion and spraying), research findings demonstrate that alternative decontamination technologies also hold promise for future utilization by the food industry. Such promising decontamination technologies are vacuum infiltration, vapor-phase application, and surface pasteurization with decontamination solutions (Delaquis et al., 1997; Deumier, 2004; Sapers, 2001). Vacuum infiltration has been shown to be an effective means of decontamination of various food commodities including produce and meat/poultry products. ...
... Finally, the application of organic acids treatments on raw materials may enhance the microbiological safety and quality of further processed final products. Such examples include the reduction and growth suppression of pathogenic and spoilage bacteria in ground beef produced by organic acid-treated carcass parts or beef trim (Castillo et al., 2001; Dorsa et al., 1998b Dorsa et al., , 1998c Harris et al., 2006; Stivarius et al., 2002a Stivarius et al., , 2002b), in sausages prepared from decontaminated (with organic acids) pork meat (Wan et al., 2007), and in coleslaw made from acetic acid-treated cabbage (Delaquis et al., 1997). Salts of organic acids, known mainly for their antimicrobial activity when incorporated in the formulation of processed meat products (Barmpalia et al., 2005; Mbandi and Shelef, 2002), have also been evaluated with regard to their decontamination efficacy in meat, poultry and seafood products (Degnan et al., 1994; Gonçalves et al., 2005; Lin and Chuang, 2001; Stivarius et al., 2002a). ...
... In addition to conventional methods of application of chemical treatments (i.e., immersion and spraying), research findings demonstrate that alternative decontamination technologies also hold promise for future utilization by the food industry. Such promising decontamination technologies are vacuum infiltration, vapor-phase application, and surface pasteurization with decontamination solutions (Delaquis et al., 1997;Deumier, 2004;Sapers, 2001). Vacuum infiltration has been shown to be an effective means of decontamination of various food commodities including produce and meat/poultry products. ...
... Finally, the application of organic acids treatments on raw materials may enhance the microbiological safety and quality of further processed final products. Such examples include the reduction and growth suppression of pathogenic and spoilage bacteria in ground beef produced by organic acid-treated carcass parts or beef trim (Castillo et al., 2001;Dorsa et al., 1998bDorsa et al., , 1998cHarris et al., 2006;Stivarius et al., 2002aStivarius et al., , 2002b, in sausages prepared from decontaminated (with organic acids) pork meat (Wan et al., 2007), and in coleslaw made from acetic acid-treated cabbage (Delaquis et al., 1997). ...
Decontamination of food products using organic acids and other chemical treatments has been and continues to be one of the most important interventions for controlling their microbiological safety and quality. This chapter first covers aspects pertinent to the principles and technology of decontamination with chemical agents, and then reviews food decontamination applications of chemical treatments, with a particular emphasis on organic acids, as well as information regarding their mode of action and effectiveness against spoilage and/or pathogenic bacteria. Additional topics discussed in the chapter include potential effects of chemical decontamination on food quality, concerns and risks other than food quality associated with this type of intervention, and regulatory aspects of its implementation.
... In general, mould growth is retarded at low temperatures, low pH, and in the presence of acetic acid. Delaquis et al. (1997) obtained more than 2 log reductions of yeast and moulds in a coleslaw (cabbage mixed with 25% mayonnaise) stored at 5°C. Despite the decline at the beginning of the incubation period, mould colonies eventually (after 22 days) appeared on the surface of the coleslaw. ...
Stored pome, stone fruit and berry crops are subject to postharvest decay if they are not protected against plant pathogens such as Botrytis cinerea, Penicillium expansum, Monilinia spp., or Rhizopus stolonifer. Decay in table grapes primarily caused by B. cinerea is prevented by frequent fumigations with sulfur dioxide over the storage period. Although there are many advantages to the use of fumigation, it is used infrequently for the control of postharvest decay. Studies on a wide range of materials that can be used as fumigants has identified several that appear to be good candidates for use on berries, pome fruit, and stone fruit to prevent postharvest decay. In this review the focus is on two classes of naturally occurring chemicals used as fumigants, acetic acid and plant volatile compounds. The first that is discussed is acetic acid usually applied as a vapor of glacial acetic acid or occasionally as vinegar. Details are presented on its use for both large and small volumes of produce as well as its use as a sanitizing agent for storage rooms and bins. Results from several published studies with a wide range of crops and under various conditions of temperature and humidity are summarized. These results provide a good picture of the efficacy of AA vapor and its potential to cause phytotoxicity on certain crops. Two compounds identified as plant volatiles, hexanal and 2-trans-hexenal, are discussed in detail. In this review the emphasis is placed on their ability to inhibit postharvest pathogens and their use in an overall postharvest strategy in combination with 1-methylcyclopropene (1-MCP).
Natural antimicrobials are gaining increased interest from researchers and food manufacturers alike seeking to discover label-friendly alternatives to the widely implemented synthetic compounds. Naturally occurring antimicrobials can be applied directly to food to protect food quality, extend food shelf-life by inhibiting or inactivating spoilage microorganisms, and improve food safety by inhibiting or inactivating food-borne pathogens. There are a great number of natural antimicrobials derived from animal, plant, and microbial sources. This manuscript reviews their efficacy against spoilage and pathogenic organisms, their methods of evaluation, and their application in various foods as well as the development of novel delivery systems and incorporation with other hurdles. Expected final online publication date for the Annual Review of Food Science and Technology Volume 4 is February 28, 2013. Please see http://www.annualreviews.org/catalog/pubdates.aspx for revised estimates.
Crude extract from the herb Eleutherine americana was investigated for its antistaphylococcal activity both in vitro and in a food system. The extract activity against Staphylococcus aureus was better during incubation at 35 degrees C than at 10 and 4 degrees C. The extract exhibited excellent stability in response to heat and pH treatments. The extract was incorporated into homemade salad dressing and evaluated for its antibacterial, physical, chemical, and sensory properties. A more than 1-log reduction in S. aureus counts was observed compared with the control. Examination of lipid oxidation revealed that the extract could retard the formation of thiobarbituric acid-reactive substances in the salad dressing. The magnitude of the storage changes were minimal, and there were no significant differences in the appearance, color, taste, and overall acceptability ranking between samples supplemented with E. americana extract and the control samples. Based on all sensory attributes, the sensory evaluation from 0 to 16 days indicated that products with each extract concentration were acceptable. The extract from E. americana is a promising novel additive that can be used to improve the quality and safety of homemade salad dressing.
Food spoilage is a complex process and excessive amounts of foods are lost due to microbial spoilage even with modern day preservation techniques. Despite the heterogeneity in raw materials and processing conditions, the microflora that develops during storage and in spoiling foods can be predicted based on knowledge of the origin of the food, the substrate base and a few central preservation parameters such as temperature, atmosphere, a(w) and pH. Based on such knowledge, more detailed sensory, chemical and microbiological analysis can be carried out on the individual products to determine the actual specific spoilage organism. Whilst the chemical and physical parameters are the main determining factors for selection of spoilage microorganisms, a level of refinement may be found in some products in which the interactive behavior of microorganisms may contribute to their growth and/or spoilage activity. This review gives three such examples. We describe the competitive advantage of Pseudomonas spp. due to the production of iron-chelating siderophores, the generation of substrates for spoilage reactions by one organism from another microorganism (so-called metabiosis) and the up-regulation of phenotypes potentially involved in spoilage through cell-to-cell communication. In particular, we report for the first time the widespread occurrence of N-acyl homoserine lactones (AHL) in stored and spoiling fresh foods and we discuss the potential implications for spoilage and food preservation.
The survival of Salmonella muenster, Staphylococcus aureus and Clostridium perfringens in mayonnaise containing either acetic or citric acid as acidulant was investigated over a range of pH values. In addition, as C. perfringens sporulated so poorly that statistically meaningful data could not be obtained, spores of the related Clostridium sporogenes were used to study the survival of bacterial endospores in mayonnaise. All vegetative bacterial cells were eliminated in acetic acid mayonnaise pH<4.4 S. aureus was not eliminated from citric acid mayonnaise, in addition, at pH>5.0 both S. muenster and C. perfringens survived in this product. However, Clostridial spore numbers were virtually unaffected by any treatment. Increasing the pH and the use of citric acid to reduce the sharpness of taste inherent in acetic acid mayonnaise would not appear to give a microbiologically safe product whereas the use of acetic acid in mayonnaise at pH<4.2 should prevent survival of vegetative cells of these food poisoning bacteria in this product although spores could persist.
The effect of Modified Atmosphere Packaging (MAP) together with the addition of salad dressing and citric acid, on the storage quality of shredded cabbage and carrots, was investigated and discussed in relation to the possibility of prolonging shelf life. The advantage of MAP on Control samples was also evaluated. Microbial quality and gas analyses of the head space were determined during storage at 4°C, for periods of up to 3 weeks.
A new static-cell method for determining the gas transmission rates of packaging film is described. Unlike previous techniques, this technique is not limited to just two data points separated by a small change in gas concentration. A sample of film is pressed over the cell cavity which is then flushed with a starting gas mixture. The external side of the film is exposed to atmospheric air. Measurements of cavity gas concentration over time are used to obtain the exponential decay constant for the cell which leads directly to calculation of the gas transmission rate. Experiments were conducted with two polyethylene films and one Mylar film at temperatures ranging from 0 to 42°C. The test cells gave simultaneous values of O2 and CO2 transmission rates that were corroborated by independent tests in a MOCON apparatus. The variation of transmission rate with temperature was well described by an Arrhenius relationship. The static test cell functions reliably with no low-temperature condensation problems and permits collection of as many data points as necessary to obtain a reliable value for the decay constant.
External leaves of whole lettuce were found to have counts approximately 1 log cycle higher than subsequent inner leaf layers. A standard washing in tap water resulted in the removal of an average of 92.4% of the lettuce leaf microflora. Inclusion of 100 mg l−1 (pH c. 9) available free chlorine reduced the count by 97.8%. Adjusting the pH of hypochlorite solutions from c. 9 to 4.5–5.0 with inorganic or organic acids produced a 1.5–4.0 fold increase in the microbiocidal effect. Increasing the washing time in hypochlorite from 5 to 30 min did not decrease microbial numbers further whereas extended washing in tap water produced a reduction comparable to hypochlorite. Addition of a surfactant, Tween 80, to hypochlorite reduced microbial numbers by 99.6% but resulted in organoleptic differences. Failure of conventional water and hypochlorite washing to remove more of the microflora is ascribed to the survival of bacteria in protective hydrophobic pockets or folds in the leaf surface and some supportive electron microscopy evidence is presented.
The fate of enterohemorrhagic Escherichia coli O157:H7 was determined in three different lots of commercial mayonnaise, including four different samples from a lot implicated in an outbreak of E. coli O157:H7 infection. The initial pH of the products ranged from 3.6 to 3.9. Products were inoculated with 6.5 × 103 E. coli O157:H7/g and incubated at 5 or 20°C. Escherichia coli O157:H7 did not grow at either temperature but survived for 34 to 55 days at 5°C and for 8 to 21 days at 20°C, depending on the lot. Survival was greatest in real mayonnaise purchased at retail among six mayonnaise samples which included a reduced calorie mayonnaise. Escherichia coli O157:H7 populations decreased between 2- and 100-fold by 3 weeks at 5°C, and between 10- and 1,000-fold by 7 days at 20°C. There was little or no change in pH (<0.1 unit), aerobic plate count, mold and yeast count or Lactobacillus count (<1 log10 CFU/g) for the duration of the study. Commercial mayonnaise manufactured under good manufacturing practices is not a public health concern. Abusive handling of mayonnaise resulting in cross-contamination with E. coli O157:H7-contaminated food or contamination by an infected foodhandler is the principal basis for concern.
Within 6 h of manufacture of coleslaw, Florida, potato, Spanish and vegetable salads the concentration of acetic acid in the mayonnaise component decreased by absorption into the plant tissue, and the pH increased. Except in Spanish salad, where the concentration of acetic acid remained at an inhibitory level, these changes allowed the growth of microorganisms in salads stored at 10°C, but not at 5°C, and emphasized the need for careful control of temperature during the distribution and sale of these products.
The effect of a modified atmosphere of 20% carbon dioxide, 80% nitrogen, on the microbial development and visual shelf life of a mayonnaise-based vegetable salad is reported. The modified atmosphere delayed the spoilage of the salad at all three chosen storage temperatures. The principal organisms causing spoilage of the salads were yeasts, those spoiling the modified atmosphere packs having a fermentative ability. Modified atmosphere packaging of the vegetable salad would allow the manufacturer to increase the shelf life of the product from 40 to 54 days at 4°C storage, 12 to 22 days at 10°C storage, and 5 to 12 days at 15°C storage.
The inhibition of Salmonella enteritidis and E. coli by lactic and acetic acids, individually and as equimolar mixtures, was measured. Results confirm that the undissociated acid is the active antimicrobial species. In weakly buffered media an apparently synergistic interaction is observed between the two acids; this is ascribed to the potentiation of acetic acid in the lower pH environment created by the lactic acid. The effect could account for the stability of vegetable fermentations where no starter culture is used and asepsis is not observed.
The productivity of the standard cultural procedure for the isolation of Salmonella using preenrichment in buffered peptone water (BPW) followed by inoculation into Rappaport-Vassiliadis (RV), tetrathionate (TBG) (Difco) and selenite-cystine (SC) (Difco) enrichment broths, was compared with that using preenrichment and enrichment cultures which had been held under refrigeration (72 h at 5–10°C). Seventy-seven of 251 samples of food products were found to contain Salmonella. Refrigerated preenrichment cultures inoculated into RV medium (43°C), TBG broth (43°C) and SC broth (37°C) yielded salmonellae from 93.5, 85.7 and 54.5% contaminated samples, respectively. Refrigerated cultures in RV, TBG and SC broths, inoculated onto three selective plating media, identified 100, 87.0 and 41.6% of the contaminated samples, respectively.The selective plating medium brilliant green deoxycholate agar was at least as productive as brilliant green sulpha agar and bismuth sulphite agar, when streaked from RV and TBG broths, but was less effective when streaked from SC broth.
The death rate of Salmonella enteritidis was always faster in mayonnaise made with extra virgin olive oil than in that prepared from blended olive or sunflower oils. The acidity and the phenolic profiles of these oils differed significantly. The most acidic oils (0·5% oleic acid), the extra virgin oils, also had the most complex phenolic profiles. The acidity of sunflower and blended olive oil was 0·2% and 0·4% respectively.
Home-made mayonnaise has been associated with outbreaks of food-poisoning due mainly to Salmonella and in some cases eggs have been shown to be the principal source of infection. The survival of Salmonella spp., Clostridium perfringens and Staphylococcus aureus in mayonnaise is influenced by the pH of the mayonnaise and the choice of the acidulant used in preparation. Acetic acid (vinegar) is more germicidal than citric acid (lemon juice). It is recommended that mayonnaise is prepared with vinegar to a pH of 4·1 or less. The addition of garlic or mustard to mayonnaise at concentrations of 0·3-1·5% (w/w) results in an increase in the death rate of Salmonella enteritidis. Salt, on the other hand, has a protective effect on S. enteritidis survival at similar concentrations. The type of oil and vinegar used in mayonnaise preparation also influences the death rate. Storage of mayonnaise at refrigeration temperatures protects Salmonella spp. from acidulants and therefore a holding time of 24 h at 18-22°C is advised before refrigeration. The presence of vegetable material in the mayonnaise has the effect of reducing the toxicity of mayonnaise by absorbing acetic acid.
The risk that fermented sauce-based salads may cause microbial food poisoning is determined by a number of factors, namely contamination of the ingredients, growth and toxin production during the first stage of fermentation, and inactivation during fermentation or storage. To investigate the possible growth and persistence of spoilers and pathogens, salads were inoculated with Klebsiella pneumoniae, Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus and fermented with lactic acid bacteria. A rapid decrease of pH, in addition to a low final pH (< 4·2) were necessary to inhibit the growth and survival of Klebsiella pneumoniae. Growth or survival of B. cereus in cabbage salads fermented with different starters was not detected. In leek-cabbage-ham salads, which were inoculated with S. aureus (420 cfu g-1) and fermented at 45°C with Lactobacillus spp., S. aureus increased 5 to 6 generations, after which the numbers declined. In salads that were composed of ingredients with lower buffering capacities, less growth occurred. When L. monocytogenes Scott A was inoculated in cabbage salads, which were then fermented with different strains of Lactobacillus spp., 2 to 3 generations of growth occurred during fermentation, followed by a rapid decline to undetectable levels. Inhibition of spoilage and pathogenic bacteria was due largely to the production of organic acids and a decrease in pH. Primarily, measures should be taken to attain absence or low initial contamination with these pathogens. Proper hygienic care during processing should also be assured.
Saccharomyces dairensis and Sacch. exiguus were isolated as the spoilage flora of coleslaw stored at 5 degrees and 10 degrees C. The growth of these yeasts in mixtures of mayonnaise with vegetable was inhibited by onion. Mayonnaise alone killed the yeasts, primarily because of its content of acetic acid and this effect increased as the temperature was increased and as the pH was decreased. Addition of cabbage or carrot tissue removed the lethal effect of mayonnaise and allowed spoilage, by absorbing acetic acid and increasing the pH.
The microbiology of a common commercial type of coleslaw was investigated with the objective of extending its shelf life at refrigerator temperature by delaying microbiological spoilage. Cabbage, its principal ingredient, had a total bacterial count of about 10/g. Microbial growth in cabbage was prevented by storage at 1 C but not at 10 C or above. In coleslaw, the cabbage flora died and was replaced by the flora of the cultured sour cream contained in the dressing. At 14 C, the total count increased and the coleslaw deteriorated organoleptically. At 7 C, bacterial growth was suppressed but organoleptic deterioration occurred as rapidly as at 14 C. Thus, the deterioration was caused primarily by the physiological breakdown of plant tissue rather than by microorganisms, as was the original premise.
Discoloration and quality maintenance in Cole slaw
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Exponential decay method for determining gas transmission of films Review: fate of pathogens in home-made mayonnaise and related products
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Process and apparatus for preserving articles of food
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