Food Science and Preservation
The Korean Society of Food Preservation
Research Note

Gamma irradiation and subsequent storage reduce patulin content in apple juice

Hyejeong Yun1,https://orcid.org/0000-0001-5100-7155, Dong-Ho Kim2,https://orcid.org/0009-0002-7184-9848, Jung-Ok Kim3https://orcid.org/0009-0003-5552-0396, Gee-Dong Lee4,*https://orcid.org/0000-0002-6840-1770, Joong-Ho. Kwon5,*https://orcid.org/0000-0002-3875-1438
1National Agriculture Products Quality Management Service, Gimcheon 39666, Korea
2Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 56212, Korea
3National Institute for Korean Medicine Development, Gyeongsan 38540, Korea
4Department of Biofood Science and Technology, Joongbu University, Geumsan 32713, Korea
5Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Korea
*Corresponding author Gee-Dong Lee, Tel: +82-41-750-6291, E-mail: geedlee@jbm.ac.kr, Joong-Ho Kwon, Tel: +82-53-765-2909, E-mail: jhkwon@knu.ac.kr

These authors contributed equally to this study.

These authors contributed equally to this study.

Citation: Yun H, Kim DH, Kim JO, Lee GD, Kwon JH. Gamma irradiation and subsequent storage reduce patulin content in apple juice. Food Sci. Preserv., 31(3), 499-505 (2024)

Copyright © The Korean Society of Food Preservation. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: Mar 25, 2024; Revised: Jun 06, 2024; Accepted: Jun 07, 2024

Published Online: Jun 30, 2024

Abstract

Patulin has been reported as a risk factor in various foods, especially apple juice. This study monitored residual patulin and polyphenolic content in apple juice during post-irradiation storage conditions. Response surface methodology (RSM) was applied to monitor the changes in dependent variables (Yn, patulin, and polyphenolics) as affected by independent variables, such as storage temperature (Xi, −20°C to 20°C), irradiation dose (Xii, 0-2 kGy), and storage period (Xiii, 0-20 days), which were based on a central composite design. The predicted peak point resulted in the lowest residual patulin content of 58.42 ppb with the corresponding independent parameter conditions, such as 18.19°C of storage temperature, 1.24 kGy of irradiation dose, and 13.42 days of storage period. The residual patulin content of 58.42 ppb is the minimum desirable level, representing a 91% reduction compared to the non-irradiated control (675.00 ppb). A maximum polyphenolics content (11.98 mg/g) was obtained under the predicted maximum conditions of 14.40°C, 0.78 kGy, and 3.4 days. The most influential parameter in reducing residual patulin content while maintaining polyphenolic content in apple juice was irradiation dose (p<0.01), which showed potential to be applied in controlling the patulin levels in apple juice.

Keywords: apple juice; gamma irradiation; patulin; polyphenolics; RSM

1. Introduction

Patulin, 4-hydroxy-4H-furan (3,2C)-pyran-2 (6H)-1, is an organic compound classified as a polyketide. It is a mycotoxin produced by approximately 30 fungal genera, including Aspergillus, Penicillium, and Byssochlamys (Boonzaaijer et al., 2005; Shephard and Leggott, 2000; Varga et al., 2003).

Patulin is found extensively in foods, such as fruits, apples, and grains. A typical symptom of patulin poisoning is acute digestive disease. It occurs mainly in infants (Drusch et al., 2007; Lai et al., 2000). Patulin has been known as a mutagen affecting the nervous and immune systems (Llewelly et al., 1998).

Especially it is reported that patulin contamination occurs most often in apples and apple juice. Studies have reported that patulin contamination in commercial apple juice was 10-350 μg/L (Ritieni, 2003; Sewram et al., 2000). Hence, patulin is an important safety factor in apples and apple juice (Mahfoud et al., 2002; Rychlik et al., 2004). The quarantine standard of patulin in apple juice is regulated at <50 μg/L (Bullerman, 1979; WHO, 1995).

Therefore, lowering patulin levels is necessary as a major risk factor for apple juice. WHO (1995) proposes that the standard for patulin content in apple juice be 50 ppb or less (Bullerman, 1979). Patulin contamination can be reduced through fermentation, leading to a negligible level in both vinegar and alcoholic fruit beverages from fruit juices. However, heat treatment rarely reduces patulin contamination, so the patulin present in apple juice survives pasteurization (WHO, 1990).

Aspergillus spp. on feeds could be controlled by 5 kGy gamma irradiation but detoxification of AFB1 demands a higher dose of gamma irradiation (≥10 kGy) (Nam et al., 2010). As gamma irradiation dose increases, the concentration of aflatoxin B1 decreases, especially at low concentrations (1 ng/ mL), aflatoxin B1 decreased by 50% to 0.5 ng/mL with 3 kGy irradiation. It was completely removed by irradiation of more than 5 kGy. Yun et al. (2008) reported the effect of gamma irradiation on the growth and patulin production of Penicillium griseofulvum in an apple model system. Zegota et al. (1988) also reported radiation-induced disappearance of the mycotoxin in relation to the absorbed dose. Ahn et al. (2022) reported that N-nitrosodimethylamine of the sausage irradiated at 10 kGy or above reduced in aerobic packaging, while a dose of 20 kGy was needed in vacuum packaging.

It is possible to control the patulin content to some extent in apple juice by different treatments, but the most practicable method is to remove rotted and damaged fruit by hand before producing the juice (Sydenham et al., 1995). According to the FDA, controlling patulin levels to ≤50 μg/kg using processors can be mainly achieved by removing damaged and/or spoiled raw apples from the product stream to produce apple juice. Other methods like water treatment can be useful for reducing patulin levels. Also, Sydenham et al. (1995) confirmed an apparent reduction in patulin levels in juice production by both initial water treatment and removal of rotted and damaged fruit by hand.

Response surface methodology (RSM) is a useful tool for optimizing chemical reaction conditions and industrial processes (Barros Neto et al., 2003; Gontard, 1992; Mayers and Montagomery, 1995). The main advantage of this RSM is to understand how the independent variables (process variables) affect the selected response variables and further to statistically determine the possible correlations between the independent variables in the responses of the process variables.

This study was conducted to monitor the changes in polyphenolic content and residual patulin content affected by gamma irradiation-combined subsequent storage by applying response surface methodology to evaluate the most influential parameters for reducing patulin content in apple juice.

2. Materials and methods

2.1. Chemicals and samples

Patulin standard and chemical reagents, such as acetonitrile, ethyl acetate, formic acid, toluene, and Folin-Ciocalteau reagent, were procured from Sigma Chemical Co. (St. Louis, MO, USA). The stock solution of patulin (1,000 ppb in distilled water) was prepared and diluted for the calibration curve. Apple juice (N Co., Seoul, Korea) was purchased from a supermarket in Jeongeup City, Korea.

2.2. Experimental design

To monitor the conditions for both reducing patulin content and minimizing the changes in the functional components of juice samples, RSM (Gontard et al., 1992) was used to observe the changes in the corresponding parameters (dependent variables) as affected by treatment conditions (independent variables), which were based on a central composite design (Kim et al., 2005; Lee et al., 2000) and the statistical analysis system (SAS, 1990). Independent variables, including storage temperature (X1, varying between −20°C and 20°C,), irradiation dose (X2, varying between 0 and 2 kGy), and storage period (X3, varying between 0 and 20 days), were coded at five levels (−2, −1, 0, 1, 2), and their values were chosen based on experiments for dependent variables (Yn), such as residual patulin content and polyphenolics content (Table 1). The central complete design consisted of 16 experimental points, including two points of center position (Kim et al., 2005; Lee et al., 2000).

Table 1. Central composite design for optimization of reducing residual patulin content and maintaining polyphenolic content in apple juice
Exp. No.1) Independent variables Response variables
Storage temp.
(X1, °C)
Irradiation dose
(X2, kGy)
Storage period
(X3, day)
Residual patulin content
(ppb)
Polyphenolics content
(mg/g)
1 −10 (−1) 0.5 (−1) 5 (−1) 259.972) 10.41
2 10 (1) 0.5 (−1) 5 (−1) 271.19 11.69
3 −10 (−1) 0.5 (−1) 15 (1) 190.45 10.32
4 10 (1) 0.5 (−1) 15 (1) 236.01 10.38
5 −10 (−1) 1.5 (1) 5 (−1) 172.79 11.70
6 10 (1) 1.5 (1) 5 (−1) 218.38 11.26
7 −10 (−1) 1.5 (1) 15 (1) 143.52 11.23
8 10 (1) 1.5 (1) 15 (1) 113.78 11.08
9 0 (0) 1.0 (0) 10 (0) 100.12 11.00
10 0 (0) 1.0 (0) 10 (0) 115.75 11.03
11 0 (0) 0.0 (−2) 10 (0) 673.26 10.41
12 0 (0) 2.0 (2) 10 (0) 237.47 11.40
13 0 (0) 1.0 (0) 0 (−2) 248.76 11.81
14 0 (0) 1.0 (0) 20 (2) 156.94 10.17
15 −20 (−2) 1.0 (0) 10 (0) 121.23 11.31
16 20 (2) 1.0 (0) 10 (0) 80.01 11.42

The number ofexperimental conditions by central composite design.

All values are mean±SD (n=3).

Download Excel Table
2.3. Gamma irradiation and storage conditions

Apple juice sample (50 mL) of a commercial product (N company) was bottled in a conical tube (polyethylene, PE), patulin (675 ppb) was injected and then irradiated with a cobalt-60 gamma irradiator (point source, AECL, IR-79, Nordion, Canada) at absorbed doses of 0, 0.5, 1.0, 1.5, and 2.0 kGy. The cobalt-60 source strength was approximately 100 kCi with 70 Gy/min dose rate at ambient conditions. The absorbed doses were monitored using free-radical and ceric/cerous dosimeters, and the actual dose ranges were within ±5.4% of the target doses. Apple juice samples were stored at −20, −10, 0, 10, and 20°C for 2 h before irradiation treatment, and then stored at the same temperature for 20 days after irradiation treatment and used in the experiment.

2.4. Determination of patulin content

Analysis of patulin was carried out using the AOAC method (1996). In a tube, each sample from the gamma-irradiated and control groups was extracted by adding 50 mL of ethyl acetate. The extracts were mixed with 20 g of anhydrous sodium sulfate, allowed to stand at room temperature for 30 min, and filtered using a Whatman No. 4 filter paper (Sigma-Aldrich). The filtrate was concentrated at 40°C under a nitrogen stream, cooled at room temperature, and stored at −70°C in distilled water (pH 4.0).

Quantitative analysis of patulin was performed by high-performance liquid chromatography (HPLC) using a Waters Alliance 2690 (Waters Co., Milford, MA, USA) system equipped with a photodiode array detector (PAD, Waters 996, Waters Co.) HPLC was performed using a Shiseido column (3.9 mm i.d., 300 mm length), and the extracts were separated using a distilled water–acetonitrile (95:5) solvent at a flow rate of 0.7 mL/min. The column temperature was maintained constant at 25°C. The patulin peak was identified using a patulin standard by comparing its retention time. Detection was conducted by acquiring the PAD spectra of eluted compounds (200-400 nm). Based on chromatograms obtained at 276 nm. The entire UV spectra for all positive samples were compared with those of the external patulin standard solution analyzed under the same conditions. Control samples, along with the samples and calibration standards, were analyzed for each matrix.

2.5. Determination of polyphenolic content

The polyphenolic content was determined by the Folin-Ciocalteau colorimetric method (Gao et al., 2000). The extracts (0.9 mL) were mixed with 0.1 mL of 50 units/mL of ascorbic oxidase and then incubated for 90 min at 23°C to remove ascorbic acid. Next, the ascorbic acid-free extract (0.1 mL) was mixed with 0.2 mL of Folin-Ciocalteau reagent and incubated for 1 min at 23°C. After adding 3 mL of 5% Na2CO3 and incubating for 2 h at 23°C, the absorbance of the mixtures was recorded at 765 nm. The polyphenolic content was expressed as gallic acid equivalents.

2.6. Analysis of regression and verification of predicted optimum conditions

Triplicate determinations were conducted at all design points in a randomized order. The corresponding extracts were subjected to analysis for dependent variables (responses), such as residual patulin content (Y1) and polyphenolics content (Y2). The mean values of triplicate determinations were analyzed to fit the following second-order polynomial models to all dependent Y variables. The following model was proposed for each response of Y:

Y = b 0 + b 1 X 1 + b 2 X 2 + b 3 X 3 + b 12 X 1 X 2 + b 13 X 1 X 3 + b 23 X 2 X 3 + b 11 X 1 2 + b 22 X 2 2 + b 33 X 3 2 ,

where X1, X2, and X3 correspond to independent variables, i.e., irradiation/storage temperature, irradiation dose, and storage period; b0 is the intercept; and bn represents the corresponding regression coefficients (Gontard, 1992). A statistical analysis system from the SAS Institute (Cary, NC, USA) (SAS, 1990) was applied to predict models through regression analysis and analysis of variance. Response surfaces were developed using fitted polynomial equations. When the results demonstrated a saddle point in the response surfaces, the optimal conditions were determined using ridge analysis. Four-dimensional response surfaces were obtained using the Mathematica software (Wolfram Research, Champaign, IL, USA, 17).

3. Results and discussion

3.1. Reduction of residual patulin content

Table 1 shows the residual patulin content under the 16 experimental conditions set by the central composite design. The regression equations for the response variables (Yn) are listed in Table 2. R2 for the regression equation of Y1 was 0.9163, with a significance of <5% being recognized (p<0.05). The predicted peak point resulted in the lowest residual patulin content of 58.42 ppb with the corresponding independent parameters conditions, such as 18.19°C of storage temperature, 1.24 kGy of irradiation dose, and 13.42 days of storage period (Table 3). Patulin content of 58 ppb was desirable, representing a 91% decrease compared to the prediction of 675 ppb from the nonirradiated control sample (Table 3). Four-dimensional response surfaces for residual patulin content as affected by treatment conditions are depicted in Fig. 1, indicating that the residual patulin content decreased by the irradiation dose with the most predominant effect (p<0.01), whereas the effects of storage temperature and period on its reduction were nonsignificant (Table 4).

Table 2. Polynomial equations calculated by RSM program for reducing residual patulin content and maintaining polyphenolics in apple juice
Response variables Second order polynomials1) R2 Significance
Residual patulin content Y1 = 728.088621 + 1.986810X1 − 827.846840X2 − 22.801698X3 − 0.018315X12 − 1.023421X1X2 + 347.422072X22 − 0.102468X1X3 − 1.458808X2X3 + 0.949145X32 0.9163 0.0126
Polyphenolics content Y2 = 11.333125 + 0.077562X1 + 0.40125X2 − 0.098375X3 + 0.000875X12 − 0.04825X1X2 − 0.011X22 − 0.002325X1X3 + 0.0375X2X3 − 0.0003X32 0.9026 0.0191

X1, storage temperature (°C); X2, irradiation dose (kGy); X3, storage period (day).

Download Excel Table
Table 3. Predicted levels of treatment conditions for optimum responses of variables by the ridge analysis
Responses variables Independent variables1) Estimated response Morphology
X1 X2 X3
Residual patulin content (ppb) 0.48 0.00 9.40 675.00 (Max.) Saddle point
18.19 1.24 13.42 58.42 (Min.)
Polyphenolics content (mg/g) 14.40 0.78 3.40 11.98 (Max.) Saddle point
−5.46 0.22 15.13 9.79 (Min.)

X1, storage temperature (°C); X2, irradiation dose (kGy); X3, storage period (day).

Download Excel Table
Table 4. Regression analysis for regression models of response variables in apple juice as affected by treatment conditions
Condition F-value
Residual patulin content Polyphenolics content
Storage temperature (°C) 0.03 2.46
Irradiation dose (kGy) 12.95** 6.24*
Storage period (day) 1.27 6.87*

Significant at 5% level

Significant at 1% level.

Download Excel Table
kjfp-31-3-499-g1
Fig. 1. Four-dimensional response surface for patulin content in apple juice as affected by storage temperature (°C), irradiation dose (kGy), and storage period (day).
Download Original Figure

Patulin has been detected in apples and other fruits, such as strawberries, mangoes, grapes, bananas, and tomatoes. Damage to fruit skin, rotten raw fruits, or inappropriate technological processing steps results in fungal growth and the consequent patulin production. Physicochemical methods, including clarification, washing, filtration, and chemical treatment, were reported to reduce patulin content in apple products, including apple juice, effectively. However, gamma irradiation and subsequent storage is one of the most efficient methods to reduce patulin content in apple juice because it can be applied to the final packaged products in an automatic conveyor system without further contamination during the drying and/or packaging processes of the treated products. UV radiation inactivates primary microorganisms and reduces patulin content (Kitipong et al., 2012). If the initial patulin contamination level is approximately 1,000 ppb (mg/liter), the UV exposure, ranging from 14.2 mJ/cm2 (one pass) to 99.4 mJ/cm2 (seven passes), was successful in reducing patulin levels by 72.57% to 5.14%, respectively.

3.2. Changes in polyphenolic content

Polyphenolic compounds in apples are health-beneficial ingredients with antioxidant and antibacterial functions (Gardner et al., 2000). The conditions for minimizing the changes in polyphenolic content were investigated when applying gamma irradiation and subsequent storage at various temperature conditions.

The polyphenolic content of apple juice according to the designed conditions is shown in Table 1. The changes in polyphenolic content under three different treatment conditions are illustrated in Fig. 2. The regression equation for polyphenolic content (Y2) revealed an R2 of 0.9026; its significance was confirmed within a level of 5% (Table 2). The maximum polyphenolics content of apple juice was 11.98 mg/g under irradiation/storage temperature of 14.40°C, irradiation dose of 0.78 kGy, and storage period of 3.4 days (Table 3). The polyphenolic content was reduced to 9.79 mg/g when the storage period exceeded 15.13 days, even at a low gamma irradiation dose of 0.22 kGy (Table 3). The polyphenolic content of apple juice was significantly influenced by the irradiation dose and storage period (p<0.05, Table 4).

kjfp-31-3-499-g2
Fig. 2. Four-dimensional response surfaces for polyphenolic content in apple juice as affected by storage temperature (°C), irradiation dose (kGy), and storage period (day).
Download Original Figure

Possible mechanisms of the effect of radiation processing on phenolic compounds in mature, dry seeds of cereal and legumes are proposed, and higher irradiation doses also cause the breakage of the glycosidic bonds of phenolic compounds with carbohydrates (Shi et al., 2022). However, applied doses for apples or apple juices are too low to affect the glycosidic bonds of phenolic compounds.

4. Conclusions

Residual patulin and polyphenolic contents were monitored in apple juice under gamma irradiation and subsequent storage conditions to predict the most influential parameters for reducing patulin content in apple juice while maintaining its polyphenolic content by applying RSM. Based on the response surface models, irradiation dose (kGy) was predicted to be the most influential variable, followed by storage periods. The residual patulin content of 58.42 ppb is the minimum desirable level, representing a 91% reduction compared to the non-irradiated control (675 ppb). A maximum polyphenolics content (11.98 mg/g) was obtained under the predicted maximum conditions of 14.40°C, 0.78 kGy, and 3.4 days. Although further studies are needed on the mechanisms of patulin reduction in foods upon gamma irradiation, our results suggest that gamma irradiation may have potential applications in controlling patulin levels in foods, including apple juice.

Acknowledgements

None.

Conflict of interests

The authors declare no potential conflicts of interest.

Author contributions

Conceptualization: Kim DH, Kwon JH. Methodology: Yun H, Kim DH. Formal analysis: Kim JO, Lee GD. Validation: Yun H, Kim JO, Lee GD. Writing - original draft: Yun H, Kim DH. Writing - review & editing: Lee GD, Kwon JH.

Ethics approval

This article does not require IRB/IACUC approval because there are no human and animal participants.

Funding

None.

ORCID

Hyejeong Yun (First author) https://orcid.org/0000-0001-5100-7155

Dong-Ho Kim (First author) https://orcid.org/0009-0002-7184-9848

Jung-Ok Kim https://orcid.org/0009-0003-5552-0396

Gee-Dong Lee (Corresponding author) https://orcid.org/0000-0002-6840-1770

Joong-Ho Kwon (Corresponding author) https://orcid.org/0000-0002-3875-1438

References

1.

Ahn HJ, Kim JH, Jo C, Lee CH, Byun MW. Reduction of carcinogenic N-nitrosamines and residual nitrite in model system sausage by irradiation. J Food Sci. 67:1370-1373 2022;

2.

AOAC Official Methods of Analysis. of the 15th ed, Association of Official Analytical Chemists, Washington DC, USA.:850 1997; .

3.

Boonzaaijer G, Bobeldijk I, Osenbruggen WA. Analysis of patulin in Dutch food, an evaluation of a SPE based method. Food Control. 16:587-591 2005;

4.

Bullerman LB. Significance of mycotoxins to food safety and human health. J Food Prot. 42:65-86 1979;

5.

Drusch S, Kopka S, Kaeding J. Stability of patulin in a juice-like aqueous model system in the presence of ascorbic acid. Food Chem. 100:192-197 2007;

6.

Gao X, Bjork L, Trajkovski V, Uggla M. Evaluation of antioxidant activities of rosehip ethanol extracts in different test system. J Sci Food Agric. 80:2021-2027 2000;

7.

Gardner PT, White TAC, McPhail DB, Duthie GG. The relative contributions of vitamin C, carotenoids and phenolics to the antioxidant potential of fruit juices. Food Chem. 68:471-474 2000;

8.

Gontard N, Guilbert S, Cuq JL. Edible wheat gluten films: Influence of the main process variables on film properties using response surface methodology. J Food Sci. 57:190-195 1992;

9.

Kim HK, Lee GD, Kwon JH, Kim KH. Monitoring on extraction yields and functional properties of Brassica oleracea var. capita extracts. Food Sci Biotechnol. 14:836-840 2005; .

10.

Kitipong A, John JC, David CM, Randy WW. Patulin reduction in apple juice from concentrate by UV radiation and comparison of kinetic degradation models between apple juice and apple cider. J Food Prot. 75:717-724 2012;

11.

Lai CL, Fuh YM, Shih DYC. Detection of mycotoxin patulin in apple juice. J Food Drug Anal. 8:85-96 2000;

12.

Lee GD, Lee JE, Kwon JH. Application of response surface methodology in food industry. Food Sci Ind. 33:33-45 2000; .

13.

Llewelly GC, McCay JA, Brown RD, Musgrove DL, Butterworth LF, Munson AE, White KL. Immunological evaluation of the mycotoxin patulin in female B6C3F(1) mice. Food Chem Toxicol. 36:1107-1115 1998;

14.

Mahfoud R, Maresca M, Garmy N, Fantini J. The mycotoxin patulin alters the barrier function of the intentional epithelium: Mechanism of action of the toxin and protective effects of glutathione. Toxicol Appl Pharmacol. 181:209-218 2002;

15.

In: Mayers RH, Montgomery DC, editors. Response Surface Methodology: Process And Product Optimization Using Designed Experiments.John Wiley and Sons New York. USA: 1995.

16.

Nam BR, Kim K, Ryu HJ, Nam M, Shim WB, Yoon Y, Kim JH, Lee JW, Byun MW, Chung DH. Influence of gamma-irradiation on the growth of Aspergillus spp. on feeds for ensuring feed safety. Korean J Food Sci Technol. 42:317-322 2010; .

17.

Neto BB, Scarminio IS, Bruns RE. Como Fazer Experimentos. 2nd ed, Unicamp, Brazil.:251-266 2003; .

18.

Ritieni A. Patulin in Italian commercial apple products. J Agric Food Chem. 51:6086-6090 2003;

19.

Rychlik M, Kircher F, Schusdziarra V, Lippl F. Absorption of the mycotoxin patulin from the rat stomach. Food Chem Toxicol. 42:729-735 2004;

20.

SAS SAS/STAT: User’s Guide, Version 6, Vol. 2, Chapter 37, 4th ed, SAS Institute, Cary, NC, USA.:1457-1478 1990; .

21.

Sewram V, Nair JJ, Nieuwoudt TW, Leggott NL, Shephard GS. Determination of patulin in apple juice by high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry. J Chromatogr A. 897:365-374 2000;

22.

Shephard GS, Leggott NL. Chromatographic determination of the mycotoxin patulin in fruit and fruit juices. J Chromatogr A. 882:17-22 2000;

23.

Shi Z, Liu Y, Hu Z, Liu L, Yan Q, Geng D, Wei M, Wan Y, Fan G, Yang P, Yang H. Effect of radiation processing on phenolic antioxidants in cereal and legume seeds: A review. Food Chem. 396:133661 2022;

24.

Sydenham EW, Vismer HF, Marasas WFO, Brown N, Schlechter M, Westhuizen L, Rheeder JP. Reduction of patulin in apple juice samples-influence of initial processing. Food Control. 6:195-200 1995;

25.

Varga J, Rigo K, Toth B, Teren J, Kozakiewicz Z. Evolutionary relationships among Aspergillus species producing economically important mycotoxins. Food Technol Biotechnol. 41:29-36 2003; .

26.

WHO Evaluation of certain food additives and contaminants. In: 44th Report of the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives, Technical Report Series 859, Geneva, Switzerland. :36-38 1995; .

27.

WHO Toxicological evaluation of certain food additives and contaminants, Chapter Patulin. In: The 35th Meeting of Joint FAO/WHO Expert Committee on Food Additives, WHO Food Additives Series, 26, Geneva, Switzerland. :143-165 1990; .

28.

Yun HJ, Lim SY, Yang SH, Lee WY, Kwon JH, Lim BL, Kim DH. Effect of gamma irradiation on the growth and patulin production of Penicillium griseofulvum in an apple model system. Food Sci Biotechnol. 17:723-727 2008; .

29.

Zegota H, Zegota A, Bachmann S. Effect of irradiation and storage on patulin disappearance and some chemical constituents of apple juice concentrate. Z Lebensm Unters Forsch. 187:321-324 1988;