Property Characterization of Peanut Kernels Subjected to Gamma Irradiation and Its Effect on the Outgrowth and Aflatoxin Production by Aspergillus parasiticus

Peanut kernels inoculated with Aspergillus parasiticus conidia and uninoculated kernels were gamma irradiated with 0 to 15 kGy using ⁶⁰Co. Levels of 2.5 and 5.0 KGy were effective in retarding the outgrowth of A. parasiticus and reducing the population of natural mold contaminants. However, elimination of these molds was not achieved. When irradiated with doses higher than 10 KGy, seed germinations were inhibited, changes in proteins were observed and oil stabilities decreased. After 4 wk incubation of the inoculated kernels in a humidified condition, aflatoxins produced by surviving A. parasiticus ranged from 69.12 to 13.48 μg/g depending upon the original irradiation dose.     

Assessment of hot peppers for aflatoxin and mold proliferation during storage

Aflatoxin contamination and mold proliferation in three hot pepper hybrids (Sky Red, Maha, and Wonder King) were studied during 5 months of storage at three temperatures (20, 25, and 30°C) and under different packaging conditions (low-density polyethylene bags and jute bags). The presence of aflatoxins in hot pepper samples was determined by high-performance liquid chromatography with a UV-Vis detector. Sampling for analysis of aflatoxins, total mold counts, and Aspergillus counts was carried out at 0, 50, 100, and 150 days of storage. Hot peppers packed in jute bags were more susceptible to aflatoxin contamination than those packed in polyethylene bags; aflatoxin concentrations were 75% higher in peppers stored in jute bags. The effect of storage temperature resulted in aflatoxin concentrations that were 61% higher in hot peppers stored at 25 and 30°C than in those stored at 20°C. Of the three pepper hybrids, Wonder King was more susceptible to aflatoxin contamination, with a maximum of 1.50 μg/kg when packed in jute bags and stored at 25°C for 150 days. However, no sample exceeded the maximum permitted level for total aflatoxins in spices established by European Union regulations (10 μg/kg). Total mold counts and Aspergillus counts increased with storage duration, but all counts were significantly lower in peppers stored in polyethylene bags. A gradual increase in temperature during prolonged storage of hot peppers in combination with aeration may be the main reasons for increases in fungal biomass and Aspergillus proliferation with the subsequent aflatoxin production.     

Effect of gamma irradiation on microbial load and quality characteristics of minced camel meat

The effect of gamma irradiation on microbial load, chemical and sensory characteristics of camel meat has been evaluated. Camel meat was irradiated at doses of 0, 2, 4 and 6 kGy of gamma irradiation. Irradiated and non-irradiated meat was kept in a refrigerator (1–4 °C). General composition and sensory evaluation of camel meat was done two days after irradiation, whereas, microbiological and chemical analysis was done immediately after irradiation and throughout the storage periods. The results indicated that all doses of gamma irradiation reduced the total mesophilic aerobic plate counts (TPCs) and total coliforms of camel meat. Thus, the microbiological shelf-life of camel meat was significantly extended from less than 2 weeks (control) to more than 6 weeks (samples irradiated with 2, 4 or 6 kGy). No significant differences in moisture, protein, fat, thiobarbituric acid (TBA) values, total acidity and fatty acids of camel meat were observed due to irradiation. There were slight effects of gamma irradiation in both total volatile basic nitrogen (VBN) and lipid oxidation values in camel meat. Sensory evaluation showed no significant differences between irradiated and non-irradiated camel meats.     

Changes in quality, liking, and purchase intent of irradiated fresh-cut spinach during storage

The use of ionizing radiation to enhance microbial safety of fresh spinach at a maximum dose of 4 kGy has been approved by the U.S. Food and Drug Administration (FDA). However, whether spinach can tolerate those high doses of radiation is unclear. Therefore, this study was conducted to investigate the effects of irradiation and storage on quality, liking, and purchase intent of fresh-cut spinach. The oxygen radical absorbance capacity values and total phenolic content were not consistently affected by irradiation. However, the ascorbic acid content of irradiated sample decreased rapidly during storage, resulting in these samples being lower in ascorbic acid content than controls after 7 and 14 d of storage at 4 °C. Sensory evaluation by a 50-member panel revealed that purchase intent and ratings for liking of appearance, aroma, texture, flavor, and overall were not affected by irradiation at doses up to 2 kGy. Therefore, irradiation at doses up to 2 kGy may be used to enhance microbial safety without affecting consumer acceptance or overall antioxidant values of irradiated spinach.     

Sensorial and chemical quality of gamma-irradiated fresh-cut iceberg lettuce in modified atmosphere packages

A study was conducted to investigate the effects of various doses of irradiation on the quality of fresh-cut iceberg lettuce and to determine a suitable maximum dose. Fresh-cut iceberg lettuce packaged in film bags was exposed to 0, 1, 2, 3, and 4 kGy of gamma radiation and stored at 3 degrees C for 14 days. CO2 levels were higher and O2 levels were lower in packages containing irradiated lettuce than in those containing nonirradiated lettuce for most of the storage period. Comparison with nonirradiated lettuce indicated that total ascorbic acid (ascorbic acid plus dehydroascorbic acid) content and firmness were not significantly influenced by irradiation at 1 or 2 kGy. The overall visual appearance was best for lettuce irradiated at 1 or 2 kGy. This improved quality may be related to the high CO2 and low O2 levels observed for the irradiated samples. Electrolyte leakage for lettuce increased with higher radiation doses and was correlated (R2 = 0.99) with a soggy appearance. The leakage for lettuce irradiated at > or = 2 kGy was significantly more extensive than that for nonirradiated lettuce. The irradiation of fresh-cut lettuce in modified atmosphere packages at doses of 1 kGy and perhaps 2 kGy for safety enhancement and quality improvement is feasible.     

EFFECT OF GAMMA IRRADIATION ON SOME CHARACTERISTICS OF SHELL EGGS AND MAYONNAISE PREPARED FROM IRRADIATED EGGS

Shell eggs were irradiated at doses of 0.0, 0.5, 1.0 and 1.5 kGy of gamma irradiation. Immediately after irradiation, bacterial, physical and chemical analyses of eggs and sensory evaluation of the mayonnaise prepared from irradiated egg yolk were performed. Results indicated that all doses of gamma irradiation reduced the total counts of mesophilic bacteria and total coliforms of eggs. The radiation dose required to reduce the Salmonella load one log cycle (D₁₀) in eggs was 448 Gy. Eggs irradiated with 1.5 kGy may be suitable microbiologically to prepare safe mayonnaise. There were no significant differences in saturated fatty acids (C14:0; C16:0; C18:0) and thiobarbituric acidvalues between the yolk lipid extracted from irradiated eggs and that of nonirradiated ones. Gamma irradiation reduced the viscosity of egg whites. Sensory evaluation showed no significant differences between mayonnaises prepared from irradiated and nonirradiated egg yolks.     

Effects of electron-beam irradiation on the shelf life, microbial populations and sensory characteristics of summer truffles (Tuber aestivum) packaged under modified atmospheres

The effects of two doses of electron-beam irradiation (1.5 kGy and 2.5 kGy) on the microbial populations (total mesophilic aerobes, Pseudomonas genus, Enterobacteriaceae family, molds and yeasts) and sensory characteristics of Tuber aestivum packaged under modified atmospheres were monitored immediately after treatment, and weekly during 42 days of storage at 4 °C. Treatment with 1.5 and 2.5 kGy reduced the pseudomonads populations by 4.3 and 5.5 logs, respectively. Enterobacteriaceae counts decreased by 5.4 logs with the 1.5 kGy dose and counts below the detection limit (<1.0 log cfu/g) were obtained with the 2.5 kGy dose. Lactic acid bacteria and yeasts were less affected by the ionizing radiation treatments and they became the dominant microbial populations throughout storage with microbial counts up to 7.1 log cfu/g. The carbon dioxide levels inside the packages containing irradiated truffles were lower than those of the non-irradiated ones, suggesting a decrease in the respiration rate of the treated ascocarps. The treatments with 1.5 and 2.5 kGy e-beam did not negatively affect the sensory characteristics of truffles, but a visible superficial yeast growth was detected in truffles irradiated with 1.5 kGy at the end of their shelf life (day 28). Treatment with 2.5 kGy e-beam has prolonged the shelf life to 42 days, compared with 21 days for the untreated samples.     

Improvement of shelf-life and wholesomeness of ground beef by irradiation 1. Microbial aspects

Various doses of ionizing radiation (cobalt-60) were used to improve the microbiological quality of commercial ground beef. The study included the isolation and identification of the natural microbial flora. The radioresistance of the individual strains was investigated. D(10) values, obtained in a saline solution, showed values ranging from 0·035 to 1·827 kGy. Treatment of ground beef with gamma radiation at doses of 1·0, 2·5 and 5·0 kGy resulted in extended shelf-life at 4°C of 4, 10 and 15 days, respectively while the control samples already exceeded 10(7) colony forming units (CFU)/g on day 0. Dominant groups of bacteria shifted from Gram-negative bacilli to Gram-positive cocci as the irradiation dose increased. Gram-negative cocci as well as yeasts and moulds also developed in greater proportion during storage of the irradiated samples.     

Control of the potential health hazards of smoked fish by gamma irradiation

This study aims to control the presence of Listeria monocytogenes and Vibrio parahaemolyticus and the formation of biogenic amines in cold-smoked salmon by gamma irradiation. Irradiation at doses of 3 and 1 kGy inactivated 6.59 and 6.05 log cfu/g of L. monocytogenes and V. parahaemolyticus in the inoculated samples, respectively. Furthermore, irradiation of the un-inoculated samples significantly decreased their microbial populations of mesophilic aerobic bacteria, anaerobic bacteria, psychrophilic bacteria, lactic acid bacteria, and molds and yeasts. The Enterobacteriaceae were almost undetectable in samples irradiated at 2 kGy dose. The concentrations of biogenic amines significantly decreased in the irradiated samples due to microbial inactivation. However, irradiation of samples had no significant effects on their moisture and salt contents as well as on their pH values, total volatile base nitrogen, and trimethylamine nitrogen contents, but significantly decreased their amounts of phenolic compounds and increased their levels of thiobarbituric acid reactive substances. Moreover, irradiation treatments at doses up to 3 kGy showed no significant effect on the sensory acceptability of samples. Therefore, gamma irradiation at dose of 3 kGy can be successfully applied to provide significant improvement in the safety of cold smoked salmon with respect to L. monocytogenes, V. parahaemolyticus, and biogenic amines without adverse effects on chemical or sensory quality attributes of the product.     

Effects of gamma irradiation on aflatoxins

The effects of gamma irradiation on a mixture of aflatoxins B1, B2, G1, G2 were studied. Standard solutions of A and B were irradiated at 5, 10, and 20 kGy in a solution of water/DMSO (9 + 1, v/v) by using a 137Cs source. The control (0 kGy) and irradiated samples were subjected to RP-HPLC analyses with methanol/water (4 + 5, v/v) as the mobile phase. Aflatoxin B1 (AFB1) was the most radio-sensitive of the four compounds. The radiosensitivity of the other aflatoxins, was in increasing order: G2, B2, G1. Only about 5% of AFB1 remained after irradiation of solution A at 5 kGy. When the concentration of solution B was increased two-fold, trace amounts of AFB1 remained after irradiation doses of 10 and 20 kGy. Irradiation was found to be suitable for the destruction of aflatoxins in solution.     

The potential use of irradiation to extend the shelf-life of clams (Ruditapes decussatus) during live storage: effect on bacterial and biochemical profiles

Changes in microbiological and biochemical quality of clams ( Ruditapes decussatus ) subjected to low doses of gamma irradiation (0.5 and 1 kGy) were investigated during alive storage, at 5 °C. The mortality rate was significantly lower for irradiated clams compared with the control. In the same way, ammonia content was lower for irradiated clams (especially 1 kGy irradiated group). Considerable levels of total mesophiles, coliforms, staphylococcus, faecal streptococcus and Escherichia coli were detected in the control and irradiation had immediately reduced these charges; all bacteria studied experienced a 1- to 3-log reduction following 1 kGy irradiation. At the last day of storage, irradiated groups showed a noticeable reduction in the bacterial counts, whereas the mesophiles, staphylococcus and coliform germs were abundant in the control group (6.3, 2 and 1.7 log CFU g⁻¹, respectively). Irradiation doses up to 1 kGy had not an immediate effect on fatty acids composition ( P  > 0.05) and lipid profile was better in irradiated samples, where polyunsaturated fatty acid fraction was maintained throughout storage using irradiation. Also, sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed minor changes in proteins bands between different samples. These results demonstrated that 1 kGy irradiation appeared to be the optimum dose for treating alive clams ( R. decussatus ), through improving the microbial quality and alleviating biochemical changes during refrigerated storage.     

Effects of low dose gamma irradiation on microbial inactivation and physicochemical properties of fried shrimp (Penaeus vannamei)

Changes in microbiological, physicochemical and sensory properties of shrimp gamma irradiated with ⁶⁰Co at doses of 0, 1, 3, 6, 9 kGy were investigated. Irradiation at 6 kGy eliminated most of the spoilage microorganisms and did not affect sensory quality. The L* value increased as irradiation dose increased, while a* value decreased as irradiation dose increased. Irradiation had no significant effect on the texture of shrimp samples; however, increasing the dose up to 9 kGy significantly increased the amount of volatile compounds, such as, alcohols, ketones, aldehydes, furans, and oxides. According to the total sensory points, the appearance and flavour of the shrimp product was considered as acceptable by sensory evaluation when irradiated at doses of 0–6 kGy. These results showed that gamma irradiation processing (<6 kGy) had the potential to extend the shelf life of fried shrimp.     

Einfluß der Gamma-Bestrahlung auf die Lipidkomponente von Sojaproteinprodukten

Effect of gamma irradiation on lipid components of soya protein products. The study deals with the effects of gamma irradiation at doses of 1,3 and 5 kGy on lipid components of soya protein products. Though the above irradiation doses do not induce changes in lipid and phospholipid content, they effect significant changes in the relationship among fatty acids. Compared with untreated samples, irradiation doses of 3 and 5 kGy caused significant changes (p ≦ 0,05 and p ≦ 0,01) in the correlation between fatty acids. The 1 kGy dosis did not produce significant changes in the correlation between fatty acids. The degree of lipid oxydation heightened with the increase in the dose of irradiation. Compared with controls, the content of total carotenoid pigments decreased in the irradiated samples; the mean decrease ranged from 6,0% to 16,8%. The irradiation treatment applied significantly reduced total germinating bacteria count and those of aerobic sporogenic bacteria and mold spores.     

Effect of low dose gamma irradiation on beef quality and fatty acid composition of beef intramuscular lipid

Eight Chinese Yellow Cattle semitendinous muscles were irradiated using a (60)Co irradiation source (with the dose of 1.13, 2.09, or 3.17kGy) and stored (0 day or 10 days at 7°C) to estimate fatty acids change of neutral lipid (NL), polar lipid (PL) and total lipid (TL) fractions, and the beef quality change. Total saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) increased with irradiation, ratios of MUFA to SFA did not change in TL. Whilst, total polyunsaturated fatty acid (PUFA) reduced with irradiation, which resulted in PUFA to SFA ratio decreased in TL (0 day or 10 days). Purge loss and 2-thiobarbituric acid reactive substances values increased with irradiation (from 0 to 3.17kGy) at 0 day, but these values were lower with irradiation at 10 days. Total bacterial counts decreased proportionally with irradiation dose increasing from 0 to 3.17kGy. It can be concluded that fatty acid profiles in beef changed with irradiation; however, fatty acid profiles did not change much at 3.17kGy compared with 1.13 or 2.09kGy, and the beef quality were most acceptable at the dose of 3.17kGy, thus, low dose of about 3kGy gamma irradiation was recommended to apply in fresh beef preparation.     

Shelf Life and Sensory Characteristics of Baby Spinach Subjected to Electron Beam Irradiation

Abstract: The use of ionizing radiation for the control of foodborne pathogens and extending the shelf life of fresh iceberg lettuce and fresh spinach has recently been approved by the U.S. Food and Drug Administration. The efficacy of electron beam irradiation for controlling foodborne pathogens has been reported. For this experiment, the effectiveness of electron beam irradiation on the microbiological and sensory characteristics of fresh spinach was studied. Total aerobic plate counts were reduced by 2.6 and 3.2 log CFU/g at 0.7 and 1.4 kGy, respectively. Lactic acid bacteria were reduced at both doses of e-beam but grew slowly over the 35 d of the experiment. Yeasts and molds were not reduced in samples exposed to 0.7 kGy whereas 1.4 kGy significantly reduced microbial counts. Gas compositions (O₂ and CO₂) were significantly different than controls. Oxygen levels inside the spinach sample bags decreased over time; however, O₂ levels did not drop below 1% that can induce anaerobic fermentation. CO₂ levels for all treatments increased through day 4; yet 7 d after irradiation, CO₂ level differences were not significant in both control and irradiated samples. Irradiation dose did not affect the basic tastes, aromatics, or mouth feels of fresh spinach, however; hardness attributes decreased as irradiated dose increased and slimy attributes of fresh spinach were higher in control samples compared to irradiated samples.     

Use of irradiation to control foodborne pathogens and extend the refrigerated market life of rabbit meat

This study set out to evaluate the microbiological status of rabbit meat and the possibility of using irradiation to control foodborne pathogenic bacteria and extend the refrigerated storage life of meat. Rabbit meat samples were γ irradiated at doses of 0, 1.5 and 3 kGy. The samples were stored at refrigeration temperature, then the effects of irradiation and storage on their microbiological, chemical and sensory properties were studied. Irradiation at 1.5 kGy significantly reduced the counts of Staphylococcus aureus, Listeria monocytogenes, Enterococcus faecalis and enterobacteriaceae but was not enough for complete elimination of Salmonella. However, 3 kGy dose reduced the counts of S. aureus, L. monocytogenes, E. faecalis and enterobacteriaceae by more than 3, 3, 1.4 and 4 log units, respectively, while Salmonella was not detected. On the other hand, irradiation at 1.5 and 3 kGy significantly reduced the counts of aerobic mesophilic bacteria, psychrophilic bacteria and molds and yeasts and prolonged the refrigerated shelf-life of samples to 12 and 21 days, respectively, compared to 6 days for non-irradiated controls. Irradiation of samples significantly increased their amounts of thiobarbituric acid reactive substances (TBARS) but had no significant effects on their total volatile nitrogen (TVN) contents, while storage significantly increased the TBARS and TVN for irradiated and non-irradiated samples. γ irradiation showed no significant effects on the sensory properties of raw meat. Moreover, fried burgers prepared from irradiated rabbit meat showed high sensory acceptability similar to those prepared from non-irradiated meat.     

电子束辐照进口冷冻牛腩的剂量分布及感官特性研究

目的 确认电子束辐照冷冻牛腩的剂量分布特性,研究不同剂量电子束辐照对冷冻牛腩的杀菌效果及辐照后产品色泽、风味、质构等感官指标的变化,为冷冻牛腩辐照杀菌的工艺设定和质量控制提供技术参考依据。方法 对不同厚度的冷冻牛腩块分别用8 kGy进行单面及双面电子束辐照,检测其内部剂量分布,确定辐照适宜的产品厚度,在此基础上用0 kGy、2 kGy、4 kGy不同剂量对商品包装（1 kg/袋,最大厚度不超过8 cm）的冷冻牛腩进行电子束双面辐照,检测菌落总数、霉菌和酵母、大肠菌群,同时利用色差仪、电子鼻、质构仪检测冷冻牛腩及其熟制品的色泽、风味、质构等感官指标。结果 单面电子束辐照冷冻牛腩的内部剂量呈先上升后下降趋势,快速下降发生在3.5~5 cm深度区域,产品厚度3.5 cm时剂量不均匀度为1.57。双面辐照可增加电子束穿透深度,8.1cm厚度双面辐照的剂量不均匀度为1.62。冷冻牛腩中菌落总数、霉菌和酵母、大肠菌群均有检出,电子束辐照可显著降低冷冻牛腩微生物水平,商品包装的冷冻牛腩经2 kGy电子束双面辐照后无大肠菌群检出,菌落总数、霉菌和酵母分别较未辐照处理降低98.8%和89.2%。电子束辐照对冷冻牛腩及其熟制品风味、质构无不良影响,4 kGy处理显著还提高了冷冻牛腩回复性,但电子束辐照导致冷冻牛腩色泽参数a值和b值显著下降,且剂量越高下降幅度越大。电子束辐照对色泽的影响程度在冷冻牛腩熟制后降低,2 kGy处理的b值显著高于未辐照处理,其它各处理的a值、b值与未辐照处理均无显著差异。结论 8.1cm厚度冷冻牛腩电子束双面辐照的剂量不均匀度为1.62,冷冻牛腩2 kGy双面辐照后无大肠菌群检出,菌落总数显著降低,风味、质构无不良变化,但色泽参数a、b值显著下降,产品红色消退,熟制可以降低辐照对色泽的不良影响。     

Influence of competitive microbial flora and inoculum size of Penicillium purpurogenum on the production of rubratoxin-B in corn medium before and after exposure to gamma radiation

The influence of inoculum size on the production of rubratoxin-B by P. purpurogenum was estimated on unirradiated and irradiated corn stored for prolonged periods at 28 °C and at a moisture content of 25%. Irradiation at doses of 1.0–3.0 kGy reduced the level of mould growth greatly relative to unirradiated controls. Rubratoxin-B production in corn grains at all doses after 40 days was less than the unirradiated control level and was below the detection limit above 4.0 kGy. Non-sterile corn that was inoculated with conidia of the fungus and then irradiated with 2.0 kGy gamma rays, produced lower rubratoxin-B levels compared with unirradiated controls. When corn was inoculated with 10⁵ spores per gram after irradiation, the spore count and rubratoxin-B level were higher than the unirradiated control after 60 days. The total viable counts of endogenous fungal flora in the corn were reduced by the 2-kGy radiation dose, but after 20 days of incubation the numbers of P. purpurogenum increased with greater enhancement of rubratoxin-B production.     

Effects of electron-beam and gamma irradiation treatments on the microbial populations, respiratory activity and sensory characteristics of Tuber melanosporum truffles packaged under modified atmospheres

The effects of electron-beam or gamma irradiation (doses of 1.5 kGy and 2.5 kGy of either one) on the microbial populations, respiratory activity and sensory characteristics of Tuber melanosporum packaged under modified atmospheres were monitored immediately after treatment, and subsequently every seven days during 35 days of storage at 4 °C. Treatments with 1.5 and 2.5 kGy reduced the total mesophilic aerobes counts respectively by 4.3 and 5.6 log cfu/g for electron-beam treatment, and by 6.4 and 6.6 log cfu/g for gamma irradiation. Other microbial groups studied (Pseudomonas genus, Enterobacteriaceae family, lactic acid bacteria, mesophilic aerobic spores, molds and yeasts) were not detected after the treatments. A decrease in the respiratory activity was detected in all the irradiated batches, indicating that the carbon dioxide levels were lower and the oxygen levels higher than those of the non-irradiated ones. Two species of yeasts, Candida sake and Candida membranifaciens var. santamariae, survived the irradiation treatments and became the dominant microbial populations with counts of up to 7.0 log cfu/g. The growth of these microorganisms was visible on the surface of irradiated truffles from day 21 onwards, affecting the flavor and the general acceptability of the ascocarps. Moreover, a watery exudate was detected in the treated truffles from the third week onwards, so the application of irradiation treatments in doses equal to or above 1.5 kGy did not preserve the quality characteristics of T. melanosporum truffles beyond 28 days.     

Shelf life extension of minimally processed cabbage and cucumber through gamma irradiation

The influence of irradiation of minimally processed cabbage and cucumber on microbial safety, texture, and sensory quality was investigated. Minimally processed, polyethylene-packed, and irradiated cabbage and cucumber were stored at refrigeration temperature (5 degrees C) for 2 weeks. The firmness values ranged from 3.23 kg (control) to 2.82 kg (3.0-kGy irradiated samples) for cucumbers, with a gradual decrease in firmness with increasing radiation dose (0 to 3 kGy). Cucumbers softened just after irradiation with a dose of 3.0 kGy and after 14 days storage, whereas the texture remained within acceptable limits up to a radiation dose of 2.5 kGy. The radiation treatment had no effect on the appearance scores of cabbage; however, scores decreased from 7.0 to 6.7 during storage. The appearance and flavor scores of cucumbers decreased with increasing radiation dose, and overall acceptability was better after radiation doses of 2.5 and 3.0 kGy. The aerobic plate counts per gram for cabbage increased from 3 to 5 log CFU (control), from 1.85 to 2.93 log CFU (2.5 kGy), and from a few colonies to 2.6 log CFU (3.0 kGy) after 14 days of storage at 5 degrees C. A similar trend was noted for cucumber samples. No coliform bacteria were detected at radiation doses greater than 2.0 kGy in either cabbage or cucumber samples. Total fungal counts per gram of sample were within acceptable limits for cucumbers irradiated at 3.0 kGy, and for cabbage no fungi were detected after 2.0-kGy irradiation. The D-values for Escherichia coli in cucumber and cabbage were 0.19 and 0.17 kGy, and those for Salmonella Paratyphi A were 0.25 and 0.29 kGy for cucumber and cabbage, respectively.