浓缩苹果汁加工链中棒曲霉素的动态分析研究

研究了浓缩苹果汁加工过程中各工序对棒曲霉素含量的影响。结果表明,喷淋、拣选、清洗是去除棒曲霉素的关键步骤,去除率为60.18％;吸附树脂对棒曲霉素去除效果显著。此外,研究了加工季节中棒曲霉素的变化规律,为果汁加工厂家建立科学完善的HACCP管理体系提供了理论依据。     

Free and bound patulin in cloudy apple juice

During validation of an HPLC-UV method for patulin analysis, a time and concentration dependent recovery of patulin was observed. Spiked cloudy apple juice was analysed on successive days, which resulted in recoveries on day 3 which were up to 20% lower than on day 1. This reduction was caused by an interaction between patulin and the solid parts of cloudy apple juice. Since these solid parts are richer in proteins compared to the liquid phase of cloudy apple juice, and the binding of patulin to proteins has been described in the literature, patulin will most probably interact with the proteins in the solid parts. As a consequence, up to 20% of the present patulin is bound and not detected during HPLC-UV analysis, which can lead to an underestimation on toxicological level.     

The effects of processing technology on the patulin content of juice during commercial apple juice concentrate production

 The effects of different treatments on the patulin content of apple juice during the production of industrial apple juice concentrate were investigated. Conventional clarification using a rotary vacuum precoat filter was found to be more effective than using ultrafiltration for the removal of patulin from apple juice. The average losses of patulin were 39% and 25% for conventional clarification and filtration, and ultrafiltration, respectively. Washing and handling appeared to be the most critical steps in removing patulin from apples since up to 54% could be removed using high-pressure water spraying. Received: 22 January 1998 / Revised version: 21 April 1998     

The effects of processing technology on the patulin content of juice during commercial apple juice concentrate production

 The effects of different treatments on the patulin content of apple juice during the production of industrial apple juice concentrate were investigated. Conventional clarification using a rotary vacuum precoat filter was found to be more effective than using ultrafiltration for the removal of patulin from apple juice. The average losses of patulin were 39% and 25% for conventional clarification and filtration, and ultrafiltration, respectively. Washing and handling appeared to be the most critical steps in removing patulin from apples since up to 54% could be removed using high-pressure water spraying. Received: 22 January 1998 / Revised version: 21 April 1998     

臭氧对苹果汁中棒曲霉素的降解效果研究

主要研究臭氧对苹果汁中棒曲霉素(Pat)的降解效果及对果汁品质的影响。研究采用臭氧对水和苹果汁中500、250、200、100、50μg/LPat浓度进行5、10、15、20、30min的降解处理。结果表明,臭氧处理对各浓度的Pat都有降解作用,浓度越低,降解效果越好。随着处理时间延长降解效果越好,15min以后降解率不再增加。臭氧处理15min,50μg/L的Pat降解效率最佳,在该条件下,臭氧对苹果汁的pH、VC含量、可溶性固形物和色值均没有明显的影响,因此,臭氧处理是高效、安全、低廉的Pat降解方法。      

陶瓷膜在苹果汁澄清中的应用研究

采用国内研制的陶瓷膜进行苹果汁的澄清实验研究.实验结果表明氧化锆陶瓷膜可有效地澄清苹果汁,澄清果汁的各项指标达到出口果汁指标;并与国外陶瓷膜设备作同期运行对比,其澄清效果、通量的稳定性等方面均达到或超过国外陶瓷膜的处理结果.同时实验还对湍流促进器强化无机膜微滤过程以及膜清洗方法进行了考察,确定了无机陶瓷膜膜过滤苹果汁合适的操作参数.     

SPE-UPLC-MS/MS测定苹果汁中展青霉素的含量

建立一套液相色谱-串联质谱法测定苹果汁中展青霉素含量的分析方法。方法:样品经水稀释后,离心,固相萃取净化处理。以甲醇-水作为流动相,C18色谱柱分离,在多反应监测负离子扫描模式下进行检测。结果表明:展青霉素标准溶液在2.0~100.0ng/m L浓度范围内,线性相关系数r=0.9991,方法检出限为2μg/kg,RSD为1.12%~2.33%,回收率在81.2%~88.5%之间。     

Factors influencing the clarification of apple juice with honey

Six apple cultivars were studied to determine the effect of pH, degree of browning and polyphenol composition on clarification of apple juice by addition of honey. The optimum pH for all apple cultivars was about 3·5. Only browned apple juices, those prepared with no ascorbic acid, flocculated with the honey and consequently clarified. The flocculation time was inversely related to the degree of browning of all apple cultivars except Golden Delicious. The clarification rate did not correlate well with the different phenolic groups present in the juices.     

Reducing patulin contamination in apple juice by using inactive yeast

The mycotoxin, patulin (4-hydroxy-4H-furo[3,2c]pyran-2[6H]-one), is a secondary metabolite produced mainly in rotten parts of fruits and vegetables, most notably apples and apple products, by a wide range of fungal species in the genera Penicillium, Aspergillus, and Byssochlamys. Due to its mutagenic and teratogenic nature and possible health risks to consumers, many countries have regulations to reduce levels of patulin in apple products. In the present study, reduction of patulin contamination in apple juice by using 10 different inactivated yeast strains was assessed. Our results indicated that nearly twofold differences in biomass existed among the 10 yeast strains. Eight of the 10 inactivated yeast strains could provide >50% patulin reduction in apple juice within 24 h, with the highest reduction rate being >72%. Furthermore, juice quality parameters, i.e., degrees Brix, total sugar, titratable acidity, color value, and clarity, of the treated apple juice were very similar to those of the untreated patulin-free juice. Potential applications of using inactivated yeast strain for patulin control are also discussed.     

Ability of inactivated yeast powder to adsorb patulin from apple juice

This study aimed to investigate the adsorption of patulin from apple juice, using two types of inactivated yeast powder: laboratory-prepared yeast powder (LYP) and commercial yeast powder (CYP). The effects of incubation time, pH, incubation temperature, adsorbent amount, and initial concentration of patulin and the stability of the yeast-mycotoxin complex were assessed. The results showed that the efficiencies of the two yeast types in adsorbing patulin were similar. The ability of the powders to remove patulin increased with longer incubation times, and patulin concentration was below detectable levels with LYP and CYP at approximately 36 and 30 h, respectively. The highest removal of patulin was achieved at pH 5.0 for both powder types, and there were no significant differences in patulin decrease at different temperatures (4, 29, and 37°C). Additionally, the adsorption percentage of patulin increased significantly with the increase of absorbent amount and decrease of initial concentration of patulin. Stability of the yeast-patulin complex was assessed, and patulin was more stable when washed in phosphate-buffered saline (pH 4.0) than in absolute ethyl alcohol. These results suggest that inactivated yeast powder has potential as a novel and promising adsorbent to bind patulin effectively.     

Long-term survey of patulin in apple juice concentrates produced in Turkey.

A liquid chromatographic method described by us elsewhere was evaluated for a long-term survey of patulin in apple juice concentrates. Patulin was separated on a reversed phase C18 LC column with water-acetonitrile (99:1) as the mobile phase and quantitated with a photodiode array (PDA) detector. Relatively low amounts of patulin (< 5 micrograms/l for single strength juice at 11.2 degrees Bx) were detected in apple juice concentrates and confirmed by PDA detector, comparing the corresponding UV spectra with that of patulin standard. Four hundred and eighty two apple juice concentrates produced through 1996-99 were analysed for their patulin contents. Year-to-year variations in patulin levels of apple juice concentrates were found out to be statistically significant. Patulin contamination levels of apple juice concentrates tended to decrease through the years and averaged 63, 43, 19 and 31 micrograms/l in 1996, 1997, 1998 and 1999, respectively. Percentages of concentrates exceeding the maximum permitted concentration of 50 micrograms/l were 52%, 34%, 8% and 8% for 1996, 1997, 1998 and 1999, respectively.     

棒曲霉素脱除树脂对苹果清汁质量指标的影响

试验对冬富士苹果清汁中棒曲霉素(Pat)脱除用的8种型号大孔吸附树脂静态吸附、解吸率进行了比较,方差分析选定LSA-900B、LS-803和XDA-600为优选树脂,检测了这3种树脂处理后苹果清汁的吸光度、色值、透光率、浊度、糖度和酸度变化。结果表明:3种型号树脂在50℃下对苹果清汁中Pat静态吸附率分别达到92.55%、90.67%和89.01%,其组间差异不显著(P<0.05);3种树脂经乙酸乙酯对Pat洗脱,静态解吸率分别达到75.91%、58.37%和75.67%,组间差异也不显著(P<0.05);经3种树脂处理后,4项正相关影响指标的波动幅度依次为浊度>吸光度>色值>透光率(α=0.01);2项负相关影响指标的波动幅度酸度>糖度(α=0.01)。     

大孔吸附树脂吸附浓缩苹果汁中棒曲霉素的研究

研究DB101 B、DM-130、AB-8、HPD-850、HPD-200L、ATF.3树脂对棒曲霉素的吸附性能及对果汁主要理化性质的影响.比较6种树脂对棒曲霉素的吸附作用,筛选出最适吸附树脂,对其进行静态和动态吸附试验,研究其吸附性能.结标明,ATF-31型树脂对棒曲霉素的吸附率为60.41%,果汁的透光率和色值分别提高4.4%和88.3%,吸附最佳操作条件为:pH 4.2,吸附流速为10 mL/min,棒曲霉素初始浓度为35.20μg/L.ATF-31型树脂是棒曲霉素的良好吸附材料,并能较好的提高浓缩苹果汁的色值与透光率.     

A quantification and confirmation method of patulin in apple juice by GC/MS

A sensitive and selective method for quantification and confirmation of patulin in apple juice by GC/MS was developed. By this method, patulin was precisely determined and confirmed down to the level of 1 and 5 microg/kg in samples, respectively. Patulin was extracted with ethyl acetate from a sample and then hexane was added to the concentrated extract solution. Significant amounts of insoluble impurities were filtered off, followed by further clean-up by solid-phase extraction with combined silica gel and Florisil cartridges. The filtration step in a low-polarity condition was very effective to remove the impurities in the sample extract solution. The eluate from the cartridges was evaporated to dryness under reduced pressure and patulin was determined and confirmed by GC/MS after derivatization with 2.5% N,O-bis(trimethylsilyl)trifluoroacetamide ethyl acetate solution. Patulin was determined in the selected ion monitoring mode (m/z 226) and confirmed in the SCAN mode (m/z 40-340). The recovery from apple juice spiked with 10-500 microg/kg ranged from 93.4 to 100%. The limits of detection and quantification were 0.1 (S/N = 3) and 1 microg/kg (S/N = 30) of patulin in samples, respectively. Levels down to 5 microg/kg of patulin in sample were readily confirmed.     

MSPD和SPE两种方法前处理苹果(汁)中棒曲霉素的比较研究

建立并比较了分别采用基质固相分散(MSPD)和氰基柱固相萃取(SPE)两种前处理技术,高效液相色谱(HPLC)检测苹果(汁)中棒曲霉素的方法.两种方法的回收率和变异系数均满足检测要求.结果表明,建立的两种方法简便、快速、准确,各有优缺点,不同的样品中棒曲霉素的前处理应采用不同的方法.