Low-Dose Irradiation Improves Microbial Quality and Shelf Life of Fresh Mint (Mentha piperita L.) without Compromising Visual Quality

ABSTRACT: The effects of low-dose irradiation (0.25 to 2 kGy) and postirradiation storage (at 4 °C) on microbial and visual quality, color values (L*, a*, b*, chroma, and hue [°]), and chlorophyll content (Chl a, Chl b, and total Chl) of fresh mint were evaluated. Samples inoculated with E. coli O157:H7, Salmonella, and MS2 bacteriophage were irradiated and evaluated. E. coli O157:H7 and Salmonella populations were reduced by 2 to 2.4, 3.5, and 5.8 log CFU/g, respectively, 1 d after treatment with 0.25, 0.60, and 1 kGy, respectively, and were completely eliminated at 2 kGy. None of the irradiation doses (P < 0.0001) reduced MS2 bacteriophage populations by more than 0.60 log PFU/g. Irradiation doses did not affect visual quality and samples remained of excellent to good quality (score 7.75 to 9) for up to 9 d of storage. Irradiation at 0.60, 1, and 2 kGy increased (P < 0.0001) Chl a, Chl b, and total Chl. Both total Chl and Chl a decreased significantly after 3 d of storage. Significant decreases in Chl b were not observed until day 12 of storage. Color values (L*, b*, and chroma) were not significantly different until day 6 of storage and hue (°) remained unchanged (179°) for the entire storage period of 12 d. Overall, irradiation did not change L*, a*, b*, or chroma. These results demonstrate that irradiation of fresh mint at 2 kGy has the potential to improve its microbial quality and extend its shelf life without compromising its visual quality and color. Practical Application: Mints and other raw fresh herbs are widely used for flavoring as well as garnish in a variety of dishes without further cooking. However, mint is one considered as one of the high-risk herbs when it comes to microbial contamination. We have evaluated the use of gamma irradiation treatment at very low doses ranging from 0 to 2 kGy to eliminate seeded Salmonella spp, E. coli O157:H7, and MS2 bacteriophage, a surrogate of hepatitis A virus. We found that low-dose irradiation (1.0 to 2.0 kGy) appears to be a promising method for improving the microbiological quality of fresh mint without compromising its visual and color attributes. This method may be applied to many popular fresh culinary herbs that are commonly used as garnishes in Asian cuisine.     

High pressure processing of garlic paste: effect on the quality attributes

The effect of high pressure treatment and conventional thermal processing on the various quality attributes of garlic paste was evaluated in terms of physicochemical, enzymatic, sensory and microbiological parameters. Thermal treatment inactivated the polyphenol oxidase and peroxidase enzymes, whereas an enhanced activity was noted at 200 MPa which reduced significantly (P < 0.05) when treated with 400 and 600 MPa. Total phenolics, flavonoids and antioxidant activities showed an increasing trend with increase in pressure, whereas thermal processing was found to significantly (P < 0.05) decrease these phytocompounds. The CIE (L*, a*, b*) values were found to be better retained in high pressure‐processed pastes compared with thermally treated one. The microbial counts in terms of total plate count, yeast and mould count as well as total coliform counts were reduced significantly (P < 0.05) in both the treatments. Sensory attributes were found to be better in the case of high pressure‐processed samples as compared to the thermally treated one.     

Survival of Lactobacillus casei and functional characteristics of reduced sugar red beetroot yoghurt with natural sugar substitutes

In this study, probiotic gel fermentation and functional characteristics of reduced sugar yoghurt with red beetroot bioactive components and steviol glycosides from Stevia rebaudiana extracts as natural source of noncaloric sweeteners were investigated. A significant increase in Lactobacillus casei viability and fermented gel network and a decrease in syneresis were determined in yoghurt sweetened with steviol glycosides and high content of red beetroot bioactive components such as total phenolics, anthocyanins and total antioxidant capacity (DPPH and FRAP). The survival of L. casei was maintained within probiotic and therapeutic levels (>9 log₁₀ CFU/g), due to the possible prebiotic effect of steviol glycosides and fermentable fibres and phenolic compounds of red beetroot during 28 days of cold storage of the probiotic yoghurts. Colour properties (L*, a*, b*, ΔE*, C*, h*) and such sensory properties as smoothness, sweetness astringency were significantly affected. The highest organic acid content was found in red beetroot enriched yoghurt with stevia, while the most dominant organic acids were butyric, lactic, malic and citric. As a result, it was determined that fermented milk products, which are supported by phytochemical and steviol glycoside interactions, have adequate nutritional effects, high probiotic viability and acceptable sensory properties     

The effect of pumpkin fibre on quality and storage stability of reduced‐fat set‐type yogurt

In this study, the effect of pumpkin fibre (PF) on physicochemical, microbiological, rheological and microstructural characteristics of reduced‐fat yogurt samples was investigated during storage. PF was added at three different concentrations (0.5%, 1.0% and 1.5%) to standardised (1.55% fat ratio) cow's milk. Plain yogurt (PF‐free) was used for comparison. The addition of PF significantly affected total solid content, synaeresis, water‐holding capacity, apparent viscosity and colour parameters (L*, a*, b*) of yogurt samples for all sampling time. The addition of PF caused a reduction in L* values (from 94.89 to 88.67), but caused an increase in a* (from ?2.10 to +4.22) and b* (from 10.79 to 25.88) values. Yogurts with PF exhibited lower synaeresis and more viscous structure than PF‐free sample during storage. SEM images showed that distinctive microstructure profile was present between samples with or without PF. More filamentous structures and denser network were observed in the SEM images and these increased with increasing level of PF. Yogurt containing 1.0% PF showed a higher storage (G′) (3687.87 at 21 day) and loss (G″) (543.10 at 21 day) moduli in comparison with other samples. In conclusion, the results revealed that PF improved the physical quality and contributed textural properties of half‐fat yogurt.     

Effects of ultrasound-assisted frying on the physiochemical properties and microstructure of fried meatballs

The aim of this study was to investigate the effects of power ultrasound (0, 200, 400, 600 and 800 W, 20 kHz) on the quality of fried meatballs. The frying time and frying temperature were also considered as fixed factors. The meatballs were fried for 8, 12 and 16 min at 120, 140 and 160 °C. Results showed that the ultrasonic groups saved about 1 to 3 min than the control group to 80 °C. Hardness, springiness, cohesiveness and chewiness of fried meatballs were significantly different among different ultrasonic treatments (P < 0.05). As for colour, the ultrasonic treatments could significantly increase the L*values. Cooking yield was from 82.58% to 85.50% in ultrasonic treatments at 120 °C for 8 min. High moisture retention and cooking yield were shown in fried-assisted ultrasound treatments and were consistent with the microstructure of scanning electron microscopy (SEM). Our data show that ultrasound-assisted frying could improve the quality of meatballs.     

Quality of fresh‐cut purple‐fleshed sweet potatoes after X‐ray irradiation treatment and refrigerated storage

The effect of X‐ray irradiation on the quality of fresh‐cut, refrigerated purple‐fleshed sweet potato (PFSP) cubes was investigated. Packaged sweet potato cubes were treated with 0, 250, 500, 750 or 1000 Gy X‐ray irradiation and stored at 4 ± 1 °C for 14 days. After 14 days, total aerobic bacteria counts were 4.1 and 3.2 log₁₀ CFU g^?1, and mould–yeast counts were 3.3 and 3.0 log₁₀ CFU g^?1 in 750 and 1000 Gy treated samples, respectively. Doses up to 1000 Gy did not affect the firmness, moisture content and anthocyanin content of PFSP cubes throughout storage. PFSP cubes' flesh colour did not change during the first week of storage, but lightness (L*) increased after 14 days. Also, irradiation doses at 750 and 1000 Gy decreased saturation (C*) significantly, producing duller flesh colour than controls. Results indicate that X‐ray irradiation treatment at doses up to 1000 Gy can reduce microbial populations while maintaining the physical quality and anthocyanin content of PFSP cubes up to 14 days of storage.     

Selected Quality Characteristics of Fresh‐Cut Sweet Potatoes Coated with Chitosan during 17‐Day Refrigerated Storage

ABSTRACT: Selected quality characteristics of fresh‐cut sweet potatoes (FCSP) coated with chitosan were evaluated during 17‐d refrigerated storage. The FCSP cubes were coated with a solution (1%, w/v) of chitosan having 470 or 1110 kDa. Color (L*, a*, b*) values of uncoated and chitosan‐coated FCSP during storage were generally affected by storage time as well as coating treatments (P < 0.05). No significant changes in color lightness (L*) of 470 kDa‐coated FCSP were observed during the 17‐d storage. During days 3 to 17, 470 kDa‐coated FCSP had significantly higher redness (a*) and yellowness (b*) values than did uncoated and 1110 kDa‐coated FCSP. Texture firmness of uncoated and chitosan‐coated FCSP exhibited minimal changes during the 17‐d storage. Although actual weight loss values (%) of uncoated and chitosan‐coated FCSP were not significantly different at day 17, the weight loss difference (%) between day 3 and day 17 for uncoated FCSP (3.02%) was slightly higher compared to those (2.24% to 2.26%) of chitosan‐coated FCSP. The initial total aerobic count was 4.7 log₁₀ CFU/g which then gradually increased to 8.54 and 9.67 log₁₀ CFU/g after 17 d of storage for 470 kDa‐coated and uncoated FCSP, respectively. After day 6, the total aerobic counts of uncoated FCSP were higher than those of 470 kDa‐coated FCSP. The yeast and mold count of chitosan‐coated FCSP was about 2.5 log₁₀ CFU/g at day 17. Overall, consumers could not differentiate between 470 kDa‐coated FCSP at day 17 and uncoated FCSP at day 0.     

Modified Atmosphere Packaging of “Napoleon” Cherry: Effect of Packaging Material and Storage Time on Physical,Chemical, and Sensory Quality

Effects of modified atmosphere and polymeric packaging material on the physical (mass loss, color, firmness), chemical (pH, total titratable acidity, total soluble solid, total phenolic content, total anthocyanin content), and sensory quality of “Napoleon” cherry (Prunus avium L. “Napoleon”) were studied. While lightness (L*) remained fairly unchanged, redness (a*), yellowness (b*), and chroma (C*) decreased during a 42-day storage period, resulting in darker fruit. Firmness did not differ significantly from the initial values (P ≤ 0.05) after 42 days of storage at 0°C. pH increased for all treatments over the storage period. In general, total titratable acidity increased during the first 2 weeks, and then decreased afterwards. Packaging significantly reduced mass losses, which were 24.08%, 0.50%, 0.39%, and 0.81% for control (unpackaged), polypropylene tray/biaxially oriented polypropylene film (PP/BOPP), polypropylene tray/cast polypropylene film, and polyvinyl chloride-polyethylene tray/polyethylene terephthalate-polyethylene films, respectively. Modified atmosphere packaging was found beneficial on extending the shelf life of fruit during storage. The shelf life of “Napoleon” cherries was suggested as 28 days for packaged samples and 14 days for unpackaged samples at 0°C. Samples packaged with PP/BOPP under 21% O₂ 79% N₂ preserved their physical, chemical, and sensory quality better than other treatments.     

Impact of pulsed electric fields and post‐mortem vacuum ageing on beef longissimus thoracis muscles

The impact of pulsed electric field (PEF) processing (0.2–0.6 kV cm^?1, 1–50 Hz, 20 μs) followed by vacuum ageing (1 and 3 days) on the quality traits of beef longissimus thoracis (LT) was assessed. The results show that pH, colour stability (L*, a* and R630/580 values) and cooking loss were unaffected by PEF treatments, whilst moisture content significantly (P < 0.05) decreased by 0.7–3.6%. No significant (P > 0.05) difference was found in shear force between PEF treated and untreated samples. However, the shear force values significantly reduced in response to ageing times regardless of the PEF treatments. After 3 days post‐treatment ageing, the shear force decreased by 20–22% compared to 1 day ageing for all samples. Furthermore, Cryo‐SEM results suggest that PEF treatments have led to more porous tissue structure leading to more water loss. Protein profile was unchanged by PEF treatments applied.     

Effects of gamma irradiation and electron beam irradiation on quality,sensory, and bacterial populations in beef sausage patties

This study compared effects of gamma ray (GR) and electron beam (EB) irradiation on quality (TBARS value, hardness, color), sensory characteristics, and total bacterial populations in beef sausage patties during accelerated storage at 30 °C for 10 days. Beef sausage patties were vacuum-packaged and irradiated by GR and EB at 0, 5, 10, 15, and 20 kGy at room temperature. The results of quality evaluation showed that the effects of GR irradiation were similar (p ? 0.05) to EB irradiation on lipid oxidation, hardness, color and sensory scores of the beef sausage patties. However, GR-irradiated samples had lower (p < 0.05) total bacterial counts than EB-irradiated samples after irradiation, and during storage regardless of irradiation dose. The results indicate that use of GR irradiation up to 10 kGy on patties should be useful in reducing bacterial populations with no adverse effect on quality and most of sensory characteristics (color, chewiness, and taste).     

Comparative study on quality characteristics of pickled and fermented sturgeon (Acipenser sinensis) meat in retort cooking

Sturgeon (Acipenser sinensis) meat has not been fully utilised due to quality defects which were raised by Chinese sturgeon processing industry. This study was aimed to develop a high-quality sturgeon meat product and the effect of fermentation on qualities was studied. Results showed that fermentation with Saccharomyces cerevisiae could enhance ‘mushroom’, ‘fruity’ and ‘chocolate’ flavour by 1-octen-3-ol, ethyl acetate and 3-methyl-butanal; and enrich flavour through mild lipid oxidation and hydrolysis. In addition, fermentation could give an attractive colour with higher a*, b* and L* value. Texture properties were also improved with higher hardness, springiness, gumminess and chewiness. Higher free amino acids, TCA-soluble peptides and taste score in fermented sturgeon meat indicated better flavour and taste. The organoleptic evaluation suggested an overall satisfactory of wine-aroma sturgeon meat by fermentation with S. cerevisiae.     

Using spray-dried sugar beet molasses in ice cream as a novel bulking agent

In this study, it is aimed to investigate and evaluate the use of molasses which is a by-product of sugar production as a novel bulking agent in ice cream as a sugar replacer. Sugar beet molasses (75%) and 12 DE maltodextrin (25%) were converted into powder form by spray drying. Spray-dried sugar beet molasses (SDSM) was then used as a substitute of sugar in different ratios (0:100, 25:75, 50:50, 75:25 and 100:0) in the ice cream products. The increased amount of SDSM decreased the overrun, L*, whiteness index (WI) and melting behaviours and increased a*, b*, total phenolic content, consistency and viscosity. Meanwhile, thermal properties have not been affected by the use of SDSM (P < 0.05). The sensory findings have been particularly interesting especially when replacing above 50% sugar with SDSM, aroma, flavour and general acceptability decrease. According to the results of this study, substituting 25% of total sugar with SDSM as a bulking agent can decrease cost of the product and improve total phenolic content and some quality parameters without compromising sensorial properties.     

Effects of exogenous 24‐epibrassinolide to control grey mould and maintain postharvest quality of table grapes

The potential of various concentrations of 24‐epibrassinolide (EBR) treatments on the control of grey mould in artificial Botrytis cinerea inoculation test and on the maintenance of postharvest quality of table grapes without inoculation in cold storage were researched. In the cold storage, clusters of grapes with exogenous EBR application (EBR1, 0.1 mg L^?1 EBR; EBR2, 0.4 mg L^?1 EBR; EBR3, 0.8 mg L^?1 EBR) were stored at 0 ± 1 °C. Fruits’ quality attributes including berry firmness, weight loss, berry drop, decay berry percentages, total sugar and titratable acidity were measured at 15, 30 and 60 days. The results showed that EBR treatments exhibited a higher berry firmness and a lower percentage of weight loss, berry drop and decay berry. In the artificial inoculation trial, single berries were immersed in EBR1, EBR2 and EBR3, then inoculated by spraying with a B. cinerea spore suspension and stored at 25 ± 2 °C and 95% relative humidity. Disease severity (DS), lipid peroxidation and defence‐related enzymes of these berries were analysed every 2 days. EBR‐treated berries resulted in an increase in activities of defence‐related enzymes including superoxide dismutase, peroxidase, catalase and phenylalanine ammonia‐lyase compared with control berries inoculated by B. cinerea. Simultaneously, significant decreases in DS and production of superoxide anion radical and malondialdehyde were observed. These results suggested that exogenous application of EBR could play a protective role in controlling the grey mould of postharvest grapes and maintaining the postharvest quality during cold storage.     

Orange juices enriched with chitosan: Optimisation for extending the shelf-life

Optimisation of the incorporation of chitosan in orange juice was accomplished by the evaluation of quality and nutritional markers. Response surface methodology was applied to obtain quadratic and second degree response surface model equations. The analyses showed that increases in chitosan concentration extended the quality of the orange juice significantly (p < 0.05), reducing enzymatic and non-enzymatic browning and controlling the spoilage during the storage time; however, concentrations > 1 g L^− 1 produced a significant (p > 0.05) reduction in the concentrations of ascorbic acid and carotenoids associated with the positive charge of chitosan and its ability to flocculate and coagulate negatively charged substances. Also, concentrations > 1 g L^− 1 were scored as unacceptable for the sensory panel due to an increase in bitterness. The study recommends the use of chitosan at concentrations up to 1 g L^− 1 to extend quality and preserve ascorbic acid and carotenoids during storage time of fresh orange juice, thus avoiding the use of standard thermal treatments which produces a negative impact on the nutritional value.

Industrial relevance

One of the major problems of fresh orange juice is its limited shelf-life. Spoilage and quick degradation of vitamins are two of the most important causes of quality loss during the shelf-life of this product. Moreover, the U. S. Food and Drug Administration issued a warning to consumers against drinking unpasteurised orange juice products because of the potential contamination with Salmonella typhimurium and its association with an outbreak of human disease caused by this organism [FDA issues nationwide health alert on Orchid Island unpasteurised orange juice. Products Recalls, Market Withdrawals and Safety Alerts.]. The main objective of this study was the study of chitosan as a natural preservative for extending the shelf-life of orange juice and as an alternative to pasteurisation.     

Extending the quality of fresh strawberries by equilibrium modified atmosphere packaging

The impact of equilibrium-modified atmosphere packaging (EMAP) technology on extension quality [pH, acidity, brix, color (L, a, Chroma, hue)] and texture profile analyses of fresh strawberries was studied and compared during storage. Cast polypropylene (CPP), linear low density polyethylene (LLDPE) and polyethylene-terephthalate (PET)/Ethylene vinyl alcohol (EVOH)/Polyetlene-low-acetyl fractions (LAF) were used as heat-sealed lid and polyvinyl chloride (PVC/PE) tray with the purpose of obtaining equilibrium atmospheres. Among the various films used, pH of fresh strawberry was 3.275 at initial days, and increased to 3.39- for LLDPE; 3.42 for CPP and 3.44 PET/EVOH-LAF at the end of 10 days’ storage. Acidity values were 0.609 mg ml⁻¹ and decreased to 0.56 mg ml⁻¹ for LLDPE; 0.47 mg ml⁻¹ for CPP and 0.49 mg ml⁻¹ for PET/EVOH-LAF at end of storage. The strawberry brix had evolved from the initial 7.125 and reduced to about from 5.6 to 6.07 at the end of the storage. At the end of the storage, the strawberry L values had not significantly changed from the initial from 29.10 (L) to 28.9–26.46. Initial values of the firmness were 1,089 gf and reduced with ranged from 769 gf to 527 gf at end of the 10-day storage period. All the parameters in texture profile analyses showed a decline, except adhesiveness and springiness and used potential indicators of fresh strawberries. The overall results expressed that strawberry quality can be maintained effectively at least for 10 days using various polymeric lid films. PET/EVOH-LAF and CPP were much more effective then LLDPE due to barrier properties during storage periods. Quality of strawberry packaged with suitable high-barrier lid films have been prolonged significantly.     

Image analysis of changes in surface color of chocolate

Blooming or the migration of fat to the surface of chocolate results in color changes and development of non-uniform color patterns. These phenomena were assessed during storage of milk chocolate tablets (cycling temp. between 16 and 28 °C for 52 days) by a computer vision system and image analysis. Eight features were extracted from images (L*, a* and b* values, whiteness index, chroma, hue, % bloom and energy of Fourier). Major changes occurred after day 36 of storage, coincidental with visual perception. Initially, white specks emerged on the brown background but were superseded by the development of a whitish color extending over most of the surface. L*, whiteness index, a* and chroma correlated well with values taken with a commercial colorimeter (R² > 0.70). Changes in image texture (energy of Fourier) followed a similar trend as color changes. The sequential forward selection strategy allowed correct classification of 97.8% of samples into four classes with only five features. The computer vision system has the capability to quantify overall changes as well as particular features over the whole chocolate surface thus enabling customization and standardization for quality assessment.     

Delayed harvest and cold storage period influence ethylene production,fruit firmness and quality of ‘Cripps Pink’ apple

The effects of harvest date and cold storage period on ethylene production, fruit firmness and quality of ‘Cripps Pink’ apple were investigated. Fruit were harvested from Perth Hills and Donnybrook (Western Australia) at commercial maturity (CM), 2, 4 and 6 weeks after CM prior to 0, 45, 90 and 135 days cold storage in 2003 and 2004. Delayed harvest significantly increased ethylene production, CIE values a* and C* at both locations in 2 years. Delayed harvest and extended cold storage period increased the internal ethylene production and reduced fruit firmness, soluble solids concentration: titratable acidity (SSC:TA) ratio and reduced CIE values L*, b*, h° during both years and locations. Fruit harvested 2 weeks after CM can be cold‐stored for 90 days with acceptable fruit quality. If the fruit is intended to be sold fresh immediately in local markets, the harvest can be delayed up to 6 weeks after CM to harness substantially improved fruit colour with acceptable fruit quality.     

Degradation Kinetics of Anthocyanin of Traditional and Low-Sugar Blackberry Jam

The objective of this study was to monitor the stability of anthocyanin and phenolic compounds contained in two formulations of blackberry jam (traditional and low-sugar) during storage. For that purpose, jams were prepared with varying amounts of hydrocolloids and investigated as to pH, total soluble solids, water activity, total acidity, total anthocyanins and total polyphenols. In order to accompany and assess the levels of phenolic compounds and colour (L*, a* and b*) changes, the samples were stored for 180 days at two different temperatures (10 and 25 °C). The Arrhenius model was used to determine the relationship between the reaction rate (k) at the different storage temperatures, yielding activation energy values of 19 and 12 kcal/mol and Q ₁₀ values of 3.0 and 2.0 for traditional and low-sugar jams, respectively. The results show that by the end of the storage time investigated, the anthocyanin compounds had been partially degraded, with the greatest loss being observed in traditional jam stored at 25 °C. Colour stability was also lower in traditional jam as compared to the low-sugar product.     

Effect of y‐radiation on chives safety and quality

The effect of γ‐irradiation on the quality of chives was evaluated. The samples were irradiated at 1.0 and 2.0 kGy, stored at 4 °C for 10 days and used for microbiological (aerobic mesophilic, moulds and yeasts, E. coli and Salmonella sp), biochemical (vitamin C and lipoperoxide (MDA) contents and superoxide dismutase (SOD) and guaiacol peroxidase (POX) activity) and sensorial evaluation. For irradiated samples, the total counts of aerobic mesophilic and moulds and yeasts showed a reduction of 6 log cycles during storage, and colour analysis showed no significant difference (P > 0.05) for the b*‐value. The contents of vitamin C were not significantly affected by irradiation and storage time. The MDA contents and SOD activity changed insignificantly at both γ‐irradiation levels after storage, while POX was significantly increased (P ≤ 0.05) at 1 kGy. Samples irradiated at 2.0 kGy presented sensorial acceptance after the storage. These results show that γ‐irradiation increases the shelf life of chives without significant changes in their quality.     

Changes in the colour and the acidity number of egg yolk upon irradiation

Eggs from laying hens were irradiated using radioactive Co-60 at a dose of 1 kGy, 2.5 kGy, and 5 kGy, with a dose input of 3.21 kGy h^–1. Parameters describing the colour of egg yolk such as L*, a*, and b*, were determined spectrophotometrically using the CIELAB system with the help of the portable spectrophotometer Superchroma S-Spex without gloss. The levels of all three parameters dropped upon ionizing radiation. While at a dose of 1 kGy the difference in the parameters was not statistically conclusive, after irradiation using doses of 2.5 kGy and 5 kGy, the levels of the parameters L*, a*, and b* showed a statistically conclusive decrease which was also accompanied with changes in sensorial properties such as decolouration and decreased colour. The colour of the yolk was evaluated according to the Roche scale, showing that more significant changes occurred upon irradiation at doses of 2.5 and 5 kGy (the value decreased from 6 to 5). The number of acidity estimated in egg yolk (mg KOH/g of fat) increased with the increasing dose, being conclusively higher only for doses of 2.5 kGy and 5 kGy.