蔣雪松,劉 鵬,沈 飛,周宏平,陳 青
(1.南京林業(yè)大學(xué)機(jī)械電子工程學(xué)院,江蘇 南京 210037;2.南京財(cái)經(jīng)大學(xué)食品科學(xué)與工程學(xué)院,江蘇 南京 210046)
衰減全反射-傅里葉變換紅外光譜法對(duì)花生仁霉變的分析
蔣雪松1,劉 鵬1,沈 飛2,周宏平1,陳 青1
(1.南京林業(yè)大學(xué)機(jī)械電子工程學(xué)院,江蘇 南京 210037;2.南京財(cái)經(jīng)大學(xué)食品科學(xué)與工程學(xué)院,江蘇 南京 210046)
為快速檢測(cè)貯藏花生的質(zhì)量安全,對(duì)滅菌后的新鮮花生仁樣品分別接種5 種常見的有害霉菌,并于26 ℃、相對(duì)濕度80%條件下貯藏9 d。利用衰減全反射-傅里葉變換紅外光譜(attenuated total reflectance-Fourier transform infrared spectroscopy,ATR-FTIR)采集不同貯藏階段花生樣品在4 000~600 cm-1的光譜信息,通過權(quán)重分析闡述花生中侵染霉菌后光譜特征的變化,并結(jié)合偏最小二乘回歸(partial least squares regression,PLSR)分析建立樣品有害霉菌污染的定量分析模型。結(jié)果表明,不同貯藏階段樣品的峰譜出現(xiàn)明顯波動(dòng),PLSR模型對(duì)單一菌株與多種菌株樣品菌落總數(shù)的預(yù)測(cè)精度較高,其中對(duì)赭曲霉3.6486處理組樣品預(yù)測(cè)模型相對(duì)偏優(yōu),有效決定系數(shù)(R2p)為0.915 7、交互驗(yàn)證均方根誤差(root mean-square error of cross-validation,RMSECV)為0.208 0(lg(CFU/g))、剩余預(yù)測(cè)偏差(residual predictive deviation,RPD)為2.52;對(duì)多種菌株預(yù)測(cè)結(jié)果R2p、RMSECV、RPD分別為0.780 3、0.358 0(lg(CFU/g))與1.76。應(yīng)用ATR-FTIR技術(shù)對(duì)花生受霉菌侵染的狀況進(jìn)行快速分析具有可行性。
衰減全反射-傅里葉變換紅外光譜;花生仁;有害霉菌;快速檢測(cè)
自然界中廣泛存在多種霉菌,易侵染貯藏期的農(nóng)副產(chǎn)品,從而造成嚴(yán)重的經(jīng)濟(jì)損失,帶來食品安全問題。許多學(xué)者著手對(duì)霉菌進(jìn)行研究,發(fā)現(xiàn)曲霉屬真菌易感染油類種子[1]如花生等,赭曲霉易感染貯藏期間的食物與谷物[2]。霉菌通過消耗農(nóng)副產(chǎn)品中的營(yíng)養(yǎng)并代謝產(chǎn)生霉菌毒素,從而嚴(yán)重危害人類與動(dòng)物的健康?;ㄉL(zhǎng)于地下,在豐收期過程中,它易攜帶土壤中存在的霉菌,如黃曲霉與寄生曲霉等[3]。在貯藏期間,由于溫度、濕度的改變,花生也極易發(fā)現(xiàn)霉變。食品中霉菌毒素的現(xiàn)有的檢測(cè)方法主要有生物學(xué)方法、免疫學(xué)方法[4]和化學(xué)儀器分析法。有學(xué)者采用了薄層色譜法[5-6]、高效液相色譜法[7-8]與酶聯(lián)免疫吸附法[9-10]等檢測(cè)了花生霉變。這些方法檢測(cè)精度高,但存在操作繁瑣、時(shí)效性差及成本高等不足。因此,亟需建立一種快速、準(zhǔn)確及便捷的方法檢測(cè)花生霉變程度。
衰減全反射-傅里葉紅外光譜技術(shù)(attenuated total reflectance-Fourier transform infrared spectroscopy,ATRFTIR)可快速檢測(cè)樣品中光譜指紋特征,反映整個(gè)細(xì)胞中的分子振動(dòng)特征[11]。它已成功用于檢測(cè)食用油中反式脂肪酸含量[12]、水果中蔗糖含量[13]、農(nóng)業(yè)環(huán)境中霉菌種類[14]、微生物及病毒分析[15]等多方面研究。在花生研究方面,Mirghani等[16]采用FTIR對(duì)購(gòu)買花生中黃曲霉毒素含量(黃曲霉毒素B1、B2、G1、G2)進(jìn)行分析,通過偏最小二乘回歸分析(partial least square regression,PLSR)方法進(jìn)行定量預(yù)測(cè),其預(yù)測(cè)決定系數(shù)(R2)均超過0.97。姜科聲等[17]采用FTIR對(duì)7 種不同花生種子之間及花生烘烤前后狀態(tài)進(jìn)行區(qū)分。Kaya-Celiker等[18]應(yīng)用ATR-FTIR對(duì)霉變花生進(jìn)行檢測(cè),通過對(duì)霉變花生中摻入潔凈花生,使花生呈現(xiàn)不同霉變狀態(tài),結(jié)合PLSR方法預(yù)測(cè)花生中黃曲霉毒素含量,從而判斷花生霉變程度,其有效決定系數(shù)(R2)達(dá)到0.99。綜上可知,應(yīng)用傅里葉紅外光譜技術(shù)檢測(cè)花生霉變的研究較早,但是對(duì)貯藏期間花生霉變程度以及對(duì)花生中菌落總數(shù)和霉菌感染的種類研究較少。
本實(shí)驗(yàn)采用ATR-FTIR技術(shù)對(duì)花生仁中5 種微量有害霉菌進(jìn)行鑒別,利用不同貯藏階段樣品的指紋光譜信息,結(jié)合權(quán)重分析花生中侵染霉菌后光譜特征的變化,并運(yùn)用PLSR對(duì)花生中菌落總數(shù)含量進(jìn)行預(yù)測(cè),為實(shí)現(xiàn)貯藏期間花生的質(zhì)量安全進(jìn)行監(jiān)控提供相關(guān)依據(jù)。
1.1 材料與試劑
花生仁樣品選購(gòu)于南京當(dāng)?shù)爻?,挑選表面沒有破損、發(fā)霉及發(fā)芽且大小均一的樣品,通過60Co強(qiáng)輻射(15 kGy)滅菌后,裝入無菌塑料密封袋中,置于4 ℃環(huán)境下,待用。
黃曲霉(Aspergillus flavus)3.17、黃曲霉(Aspergillus flavus)3.3950、寄生曲霉(Aspergillus parasiticus)3.395、寄生曲霉(Aspergillus parasiticus)3.0124與赭曲霉(Aspergillus ochraceus)3.64865 種霉菌均選購(gòu)于中國(guó)北京北納創(chuàng)聯(lián)研究所,于馬鈴薯葡萄糖瓊脂(potato dextrose agar,PDA)培養(yǎng)基上培養(yǎng)。使用時(shí),運(yùn)用無菌塑料接種環(huán)將霉菌分生孢子接種至PDA培養(yǎng)基上26 ℃、80%相對(duì)濕度條件下活化培養(yǎng)7 d,運(yùn)用無菌水沖洗分生孢子,通過平板計(jì)數(shù)方法調(diào)整無菌水調(diào)節(jié)孢子懸浮液濃度至105CFU/mL,待用。
1.2 儀器與設(shè)備
Tensor 27型傅里葉變換紅外光譜儀 德國(guó)Bruker公司;ZnSe衰減全反射附件 美國(guó)Pike公司;GNP_9160型隔水式恒溫培養(yǎng)箱 上海三發(fā)科學(xué)儀器有限公司;SW_ CJ_1F型單人雙面凈化工作臺(tái) 蘇州凈化設(shè)備有限公司;TP_214分析天平(精度0.0001 g) 丹佛儀器(北京)有限公司;FW_200型高速萬(wàn)能粉碎機(jī) 北京中興偉業(yè)儀器有限公司。
1.3 方法
1.3.1 樣品處理
稱取每份質(zhì)量約50 g的滅菌花生仁120 份,分成5 組,每組24 份。用移液器分別移取10 μL孢子懸浮液接種于每份花生仁表面,每組接種同一種霉菌,并在26 ℃、相對(duì)濕度80%條件下,貯藏9 d。期間,每隔3 d從每組中各取6 份樣品用于實(shí)驗(yàn)分析。其中,第0天花生樣品設(shè)為對(duì)照組,樣品裝入無菌密封袋中。為使花生中霉菌及其代謝產(chǎn)物分配更加均勻,采用高速萬(wàn)能粉碎機(jī)將花生磨成糊狀,并置于4 ℃環(huán)境下,待用。
1.3.2 樣品測(cè)定
在樣品掃描前,將冷藏花生糊置于室溫(23±1) ℃條件下2 h直至樣品達(dá)到室溫。采用FTIR及ATR附件掃描霉變花生糊樣品的光譜信息,ATR數(shù)據(jù)從配有ZnSe晶體的變角衰減全反射附件獲取,光線入射角為45°,樣品測(cè)量時(shí),將花生糊均勻涂覆在ZnSe晶體的凹槽中,即可進(jìn)行紅外掃描,測(cè)量結(jié)束后使用無菌毛巾擦拭干凈,再利用70%乙醇溶液擦洗ZnSe晶體,待ZnSe晶體表面乙醇完全揮發(fā)后進(jìn)行下一次測(cè)量,為了防止花生樣品在檢測(cè)出油而影響實(shí)驗(yàn)結(jié)果,并不使用壓力錘,同時(shí)以空氣為背景對(duì)樣品進(jìn)行檢測(cè),每測(cè)一個(gè)樣品前,均進(jìn)行一次背景掃描。掃描波數(shù)范圍為4 000~600 cm-1,分辨率4 cm-1,掃描64 次[19],每份花生糊掃描3 次,取平均值作為花生光譜數(shù)據(jù)。
1.3.3 樣品中菌落總數(shù)的測(cè)定
參照GB/T 4789.2—2010《食品微生物學(xué)檢驗(yàn) 菌落總數(shù)測(cè)定》[20]進(jìn)行操作。
1.4 數(shù)據(jù)處理
數(shù)據(jù)處理軟件采用TQ Analyst v6.2.1(Thermo Electron公司,美國(guó))軟件。PLSR是一種強(qiáng)有力多變量統(tǒng)計(jì)分析工具,對(duì)樣品中菌落總數(shù)含量進(jìn)行定量分析。將已獲取花生光譜數(shù)據(jù)作為自變量,菌落總數(shù)作為因變量,其中取2/3樣品作為建模集,1/3作為預(yù)測(cè)集。為了去除光譜中高頻隨機(jī)噪聲、基線漂移等帶來的誤差,采用標(biāo)準(zhǔn)正態(tài)變換、Savitzky-Golay[21](13 點(diǎn)與3 次多項(xiàng)式平滑過濾)的預(yù)處理方法。在模型評(píng)價(jià)方面,主要考察有效決定系數(shù)(R2)、建模集均方根誤差(root meansquared error o f calibration,RMSEC)、預(yù)測(cè)集均方根誤差(root mean-squared error of prediction,RMSEP)、交互驗(yàn)證均方根誤差(root mean-squared error of cross validation,RMSECV)和剩余預(yù)測(cè)偏差(residual predictive deviation,RPD)等統(tǒng)計(jì)量。其中RPD為標(biāo)準(zhǔn)偏差與預(yù)測(cè)均方根誤差的比值。
2.1 光譜區(qū)域選擇與分析
運(yùn)用ATR-FTIR收集霉變花生的光譜信息,貯藏期間花生中菌落總數(shù)的增加及代謝產(chǎn)物排出,引起花生光譜中分子鍵的改變。由圖1可以看出,4 000~1 800 cm-1波數(shù)范圍內(nèi)不同種類霉菌的光譜差異較小,在3 600~3 100 cm-1和1 700~1 500 cm-1波數(shù)范圍內(nèi)由霉菌中蛋白質(zhì)成分(主要為酰胺A、酰胺Ⅰ與酰胺Ⅱ)引起;在3 050~2 750 cm-1和1 500~1 300 cm-1波數(shù)范圍內(nèi)由脂肪與蛋白質(zhì)吸收鍵的形變振動(dòng)引起;在2 750~1 800 cm-1波數(shù)范圍內(nèi)的光譜變化較為平緩,但仍有部分噪聲波動(dòng),這是由于花生樣品放置于ATR附件上測(cè)量時(shí)ZnSe晶體表面反射所引起的;在900~600 cm-1波數(shù)范圍內(nèi)波動(dòng)主要由芳香環(huán)振動(dòng)引起。因此,本實(shí)驗(yàn)主要對(duì)1 800~900 cm-1指紋區(qū)域的光譜進(jìn)行研究。
圖1 5 種霉變花生的ATR-FTIR原始平均光譜圖Fig.1 Averaged raw ATR-FTIR spectra of peanuts infected with five different fungal species
圖2 5 種霉變花生前3 個(gè)主成分權(quán)重光譜Fig.2 Spectra of first three principal components for peanut samples infected with five different fungal species
表1 ATR-FTIR光譜區(qū)的功能團(tuán)特性[22-25]Table1 Functional groups identified from ATR-FTIR spectra[22-25]
為了進(jìn)一步分析樣品光譜特性,對(duì)所有樣品前3 個(gè)主成分進(jìn)行權(quán)重分析,結(jié)果如圖2所示,同時(shí)表1列出霉變花生中化學(xué)鍵變化波段及振動(dòng)方式。觀察可知,第1主成分的最高權(quán)重位于1 743 cm-1與1 460 cm-1處,由于酮類及脂肪引起。第2主成分的最高權(quán)重位于1 726、1 378、1 131 cm-1以及1 088 cm-1處,主要由于脂肪、酯類及多糖引起。第3主成分的最高權(quán)重位于1 650、1 543、1 238 cm-1及1 160 cm-1處,主要由于蛋白質(zhì)、磷酸鹽及多糖引起?;ㄉ棺兤陂g,蛋白質(zhì)、脂肪與多糖等為霉菌生長(zhǎng)提供主要營(yíng)養(yǎng)[26],在1 743 cm-1處由于花生中黃曲霉毒素G酮類的C=O基團(tuán)的伸縮振動(dòng)引起,同時(shí)花生中甘油三酸酯的羰基也出現(xiàn)伸縮振動(dòng),隨著脂肪被水解,脂肪酸含量增加,1 726 cm-1附近存在較強(qiáng)的峰譜。在1 695~1 543 cm-1光譜區(qū)由于蛋白質(zhì)(酰胺:amideⅠ和amideⅡ)中C=O、C—N基團(tuán)的伸縮振動(dòng)引起,在1 460 cm-1與1 378 cm-1處由于脂肪中甲基與亞甲基的C—H基團(tuán)出現(xiàn)振動(dòng)引起,在1 200~900 cm-1之間主要由多糖引起,隨著花生樣品霉變程度的加深,在1 131、1 088 cm-1處酯類的C=O基團(tuán)出現(xiàn)伸縮振動(dòng)。因此,隨著花生霉變侵染程度的加深,花生中營(yíng)養(yǎng)物質(zhì)逐漸被消耗,樣品的光譜信息也隨之改變。
2.2 花生霉變程度變化與霉菌菌落計(jì)數(shù)
谷物中侵染有害霉菌,并在適宜溫度、濕度條件下培養(yǎng),谷物中的毒素含量與菌落總數(shù)均會(huì)隨之增加[27]。本實(shí)驗(yàn)對(duì)無菌花生表面侵染5 種有害霉菌,并在26 ℃、相對(duì)濕度80%環(huán)境條件下貯藏9 d,對(duì)不同貯藏時(shí)間花生的菌落總數(shù)進(jìn)行測(cè)定,5 種霉變花生的菌落總數(shù)范圍均分布于在2~4.5(lg(CFU/g))之間,即樣品的霉變程度不斷加深。本實(shí)驗(yàn)依據(jù)菌落總數(shù)的變化將花生分成健康(低于2.7(lg(CFU/g)))、霉變(2.7~4(lg(CFU/g)))和重度霉變(高于4(lg(CFU/g)))[28]。圖3顯示:貯藏9 d期間5 種霉變花生中菌落總數(shù)的變化,可以發(fā)現(xiàn)隨著貯藏時(shí)間的延長(zhǎng),花生中菌落總數(shù)均逐漸增長(zhǎng)。在前3 d時(shí),除赭曲霉3.6486組已經(jīng)達(dá)到霉變狀態(tài)外,其他樣品霉菌生長(zhǎng)均較為平緩;到第6天時(shí),黃曲霉3.3950和赭曲霉3.6486組滋生相對(duì)較為緩慢,剩余3 組增長(zhǎng)速度明顯較快。其中,黃曲霉3.3950組仍處于健康狀態(tài),其余4 組均已達(dá)到霉變狀態(tài);到第9天時(shí),寄生曲霉3.395與寄生曲霉3.0124組滋生速度開始放緩,而黃曲霉3.3950組增長(zhǎng)速度加快,達(dá)到霉變狀態(tài)。黃曲霉3.17與赭曲霉3.6486組菌落總數(shù)均已超過4.0(lg(CFU/g)),已達(dá)到重度霉變。綜上,對(duì)無菌花生表面侵染5 種有害霉菌并貯藏9 d,花生中脂肪、蛋白質(zhì)與碳水化合物等相繼被消耗,菌落總數(shù)隨之增加,即花生霉變程度加深,從而引起花生的特征譜帶強(qiáng)度和位置的變化。
圖3 5 種霉變花生中菌落總數(shù)隨時(shí)間的變化Fig.3 Changes in total number of molds in contaminated peanut samples during storage
2.3 PLSR分析結(jié)果
表2 花生中侵染5 種霉菌PLSR分析結(jié)果Table2 PLSR regression statistics of five fungal species in infected peanut sammpplleess
利用PLSR對(duì)花生中菌落總數(shù)進(jìn)行預(yù)測(cè),從而判斷花生的霉變程度,結(jié)果如表2所示。對(duì)單一霉菌進(jìn)行建模時(shí),可以得到較高的有效決定系數(shù)(R2)與較低的建模RMSEC,其中赭曲霉3.6486處理組建立模型相對(duì)最優(yōu),即R2值為0.998 3,RMSEC為0.024 6(lg(CFU/g)),對(duì)單一霉菌進(jìn)行留一交互驗(yàn)證時(shí),所得到RMSECV也偏低,其中黃曲霉3.17處理組的RMSECV值最大,為0.409 0(lg(CFU/g)),赭曲霉3.6486處理組的RMSECV值偏小,為0.208 0(lg(CFU/g)),而進(jìn)行交互驗(yàn)證時(shí),RMSECV值的大小由PLS因子所決定[29]。對(duì)單一霉菌進(jìn)行預(yù)測(cè)時(shí),同樣得到較高的R2值與較低的預(yù)測(cè)RMSEP,RPD反映模型的預(yù)測(cè)分析能力,當(dāng)RPD不小于3時(shí),表明該模型的預(yù)測(cè)精度較優(yōu),魯棒性好,可用于實(shí)際分析;當(dāng)大于等于2且小于3時(shí),表明該模型的具有定性分析的潛力,該模型的魯棒性有待提高;當(dāng)大于等于1.5且小于2時(shí),表明該模型可用于定性分析[30]??梢钥闯鳇S曲霉3.3950處理組R2值相對(duì)最小,為0.723 1,而RMSEP值最低,為0.244 0(lg(CFU/g)),赭曲霉3.6486處理組的R2值相對(duì)最高,為0.915 7,RMSEP值已低于0.3,除了赭曲霉3.6486處理組RPD值為2.52,其余4組的RPD均低于2。綜上對(duì)比,對(duì)單一霉菌進(jìn)行預(yù)測(cè)時(shí),赭曲霉3.6486處理組得到結(jié)果相對(duì)最優(yōu),Rp2、RMSECV與RPD值分別為0.915 7、0.208 0(lg(CFU/g))與2.52。
對(duì)花生侵染5 種霉菌的光譜信息建立PLSR預(yù)測(cè)分析模型,如圖4所示,共有120 個(gè)樣品用于建模,通過計(jì)算光譜數(shù)據(jù)中心平均值與一階微分排除4 個(gè)異常樣品,其中79 個(gè)樣品作為建模集,37 個(gè)樣品作為預(yù)測(cè)集。所有樣品均分布于中心線兩側(cè),進(jìn)行PLSR建模時(shí),共計(jì)11 個(gè)因子用于建模計(jì)算,預(yù)測(cè)集Rp2、RMSECV與RPD值分別為0.780 3、0.358 0(lg(CFU/g))與1.76。結(jié)果表明,采用PLSR預(yù)測(cè)花生樣品菌落總數(shù)含量,從而判斷花生霉變狀態(tài)具有可行性。
圖4 多種霉菌感染花生后預(yù)測(cè)集模型Fig.4 Predictive model for total fungal species in infected peanut samples
本實(shí)驗(yàn)應(yīng)用ATR-FTIR技術(shù)對(duì)滅菌花生樣品中侵染5 種有害霉菌,并呈現(xiàn)出不同霉變程度的研究。花生與霉菌均具有復(fù)雜結(jié)構(gòu),通過權(quán)重分析發(fā)現(xiàn),花生的霉變程度在不斷加深時(shí),花生中脂肪、蛋白質(zhì)與多糖等成分的特征譜帶均呈現(xiàn)一定程度的波動(dòng)。運(yùn)用PLSR分析對(duì)花生中菌落總數(shù)進(jìn)行預(yù)測(cè),預(yù)測(cè)集結(jié)果Rp2、RMSECV與RPD值分別為0.780 3、0.358 0(lg(CFU/g))與1.76。結(jié)果表明ATR-FTIR技術(shù)作為一種快速、便捷的方式對(duì)貯藏期間的花生進(jìn)行檢測(cè),判斷花生是否發(fā)現(xiàn)霉變具有可行性。
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Analysis of Moldy Peanut Kernel by Attenuated Total Reflectance-Fourier Transform Infrared Infrared Spectroscopy
JIANG Xuesong1, LIU Peng1, SHEN Fei2, ZHOU Hongping1, CHEN Qing1
(1. College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China; 2. College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing 210046, China)
Peanut products are susceptible to changes in temperature and relative humidity (RH) during storage. Peanuts are easily infected by hazardous fungal species, producing a variety of potent mycotoxins. This study aimed to develop a method for the rapid detection of moldy peanuts. Firstly, clean and fresh peanut kernels were sterilized and inoculated individually with fi ve common hazardous fungal species. Then, the samples were stored at 26 ℃ and 80% RH for9 days. During this period, spectral information of the peanut samples in the wave number range of4 000 to 600 cm-1were collected using attenuated total re fl ectance-Fourier transform infrared spectroscopy (ATR-FTIR). The spectral changes of peanut samples infected with different fungal species were analyzed by loading analysis. A quantitative model to predict contamination levels of hazardous fungi in peanut samples was developed by partial least squares regression (PLSR). The results showed that the spectral alterations for the samples were clearly fl uctuated during different storage periods. The PLSR model could predict the total number of colonies of single and multiple strains in fungus-infected peanut samples with good accuracy. Especially, the model provided better prediction of Aspergillus ochraceus 3.6486 infection with a coef fi cient of determination for the prediction set (Rp2) of 0.915 7, a root mean-square error of cross-validation (RMSECV) of 0.208 0 (lg (CFU/g)) and a residual predictive deviation (RPD) of 2.52. The R2p, RMSECV and RPD values of the prediction model for total fungal species were 0.780 3, 0.358 0 (lg (CFU/g)) and 1.76, respectively. These fi ndings demonstrated that ATR-FTIR could be used as a reliable analytical method for rapid determination of fungal contamination levels in peanuts during storage.
attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR); peanut kernel; hazardous fungi; rapid detection
10.7506/spkx1002-6630-201712049
中圖分類號(hào):TS255.7;O657.33 文獻(xiàn)標(biāo)志碼:A 文章編號(hào):1002-6630(2017)12-0315-06
2016-07-24
南京林業(yè)大學(xué)青年科技創(chuàng)新基金項(xiàng)目(CX2015010);江蘇省高校優(yōu)秀中青年教師和校長(zhǎng)境外研修資助項(xiàng)目(蘇教辦師〔2015〕7號(hào));“十二五”國(guó)家科技支撐計(jì)劃項(xiàng)目(2014BAD08B04);江蘇高校優(yōu)勢(shì)學(xué)科建設(shè)工程資助項(xiàng)目(PAPD)
蔣雪松(1979—),男,副教授,博士,研究方向?yàn)樯飩鞲衅骷夹g(shù)。E-mail:xsjiang@126.com
蔣雪松, 劉鵬, 沈飛, 等. 衰減全反射-傅里葉變換紅外光譜法對(duì)花生仁霉變的分析[J]. 食品科學(xué), 2017, 38(12): 315-320.
10.7506/spkx1002-6630-201712049. http://www.spkx.net.cn
JIANG Xuesong, LIU Peng, SHEN Fei, et al. Analysis of moldy peanut kernel by attenuated total reflectance-Fourier transform infrared infrared spectroscopy[J]. Food Science, 2017, 38(12): 315-320. (in Chinese with English abstract) DOI:10.7506/ spkx1002-6630-201712049. http://www.spkx.net.cn