戚向陽,周婷婷,曹少謙
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不同強度脈沖強光對鮮香菇保鮮效果的影響
戚向陽,周婷婷,曹少謙※
(浙江萬里學(xué)院生物與環(huán)境學(xué)院,寧波 315100)
為探討脈沖強光處理對采后食用菌保鮮效果的影響,該試驗以新鮮香菇為原料,研究了不同強度(28.8、48.0、67.2 mJ/cm2)脈沖照射后的香菇在25 ℃保藏期間感官品質(zhì)、生理指標(biāo)、衰老指標(biāo)及營養(yǎng)品質(zhì)的變化。結(jié)果表明,脈沖強光處理在一定程度上能維持香菇的色澤和風(fēng)味,顯著延緩保藏過程中香菇失質(zhì)量率與硬度的下降及褐變度和丙二醛含量的上升,促使過氧化物酶和多酚氧化酶活性降低,減少總酚、維生素C及還原糖的損失。保藏至12 d時,28.8、48.0、67.2 mJ/cm2處理組香菇總酚質(zhì)量分數(shù)比對照組分別高28.44%、42.61%、17.37%,維生素C質(zhì)量分數(shù)比對照組分別高68.56%、88.45%、63.42%,還原糖質(zhì)量分數(shù)比對照組分別高12.87%、96.39%、54.16%,可見48.8 mJ/cm2處理組保持香菇營養(yǎng)品質(zhì)的效果最佳。脈沖強光處理在控制食用菌品質(zhì)方面具有潛在的應(yīng)用前景。
農(nóng)產(chǎn)品;貯藏;品質(zhì)控制;脈沖強光;香菇;保鮮品質(zhì)
香菇是一種藥食同源真菌,含有豐富的糖類、蛋白質(zhì)、維生素和礦物質(zhì)等,具有預(yù)防骨骼和心血管疾病,抗腫瘤、抗氧化、抗衰老等多種功能活性[1-2],深受消費者喜愛。新鮮香菇含水率高、組織結(jié)構(gòu)疏松多孔,采后常溫下保存呼吸作用及代謝旺盛,營養(yǎng)物質(zhì)流失快,易開傘、失水皺縮、褐變及腐敗[3-4],造成經(jīng)濟損失。香菇已有的保鮮方法有冷藏[5]、氣調(diào)[6-7]、輻照[8]和化學(xué)方法[9]等,但經(jīng)這些方式處理后仍存在品質(zhì)下降嚴重或能耗大、設(shè)備及資金要求高或殘留安全性等問題,在實際生產(chǎn)中受到諸多限制,故采取綠色、有效的措施來延長新鮮食用菌的保質(zhì)期具有重要意義。
脈沖強光(intense pulsed light, IPL)是一種現(xiàn)代非熱處理技術(shù),它由一個動力單元和一個惰性氣體燈單元組成,動力單元給惰性氣體光源提供高電壓、高電流的能量,惰性氣體燈則釋放出最多持續(xù)0.1 s、光譜成分與太陽光相似(紫外區(qū)到紅外區(qū))[10-11],但強度相當(dāng)于太陽光到達海平面20 000倍的脈沖光[12]。因此,IPL就是利用這種瞬時、廣波譜、高強度的惰性氣體燈殺死透明液體或物料表面的微生物[13-14],具有綠色、高效、安全無殘留等優(yōu)點[15],應(yīng)用于食品加工時還能保持或提高其天然品質(zhì)。Avalos-Llano等[16]發(fā)現(xiàn)IPL處理不僅能防止鮮切蘋果褐變和氧化,還提高了酚類物質(zhì)和維生素C質(zhì)量分數(shù);Kwaw等[17]的研究結(jié)果表明,IPL處理可顯著增加乳酸發(fā)酵桑椹汁中總酚、總黃酮、總花青素質(zhì)量分數(shù)及自由基清除能力;Aguiló-Aguayo等[18]用IPL處理胡蘿卜切片,使其胡蘿卜素和可溶性糖質(zhì)量分數(shù)增加。Chien等[19]的研究表明IPL處理可促使香菇中麥角甾醇向維生素D2轉(zhuǎn)化,同時總酚質(zhì)量分數(shù)及抗氧化活性升高。目前,中國關(guān)于IPL技術(shù)控制食用菌采后品質(zhì)的報道甚少[20],故本試驗對IPL處理后香菇保鮮品質(zhì)的變化進行研究,為IPL技術(shù)在食用菌的應(yīng)用中提供科學(xué)依據(jù)。
新鮮香菇(品種為地菇-139),同批采購于寧波市農(nóng)產(chǎn)品批發(fā)市場,子實體成熟度、色澤、大小均勻,無畸形、病蟲害及機械損傷。
愈創(chuàng)木酚(化學(xué)純),上海佘山化工廠;福林酚試劑(1 N),上海源聚生物科技有限公司;過氧化氫、抗壞血酸、硫代巴比妥酸、3,5-二硝基水楊酸等試劑均為分析純,國藥集團化學(xué)試劑有限公司。
C400*8*6.5-18型IPL設(shè)備,純亮殺菌設(shè)備有限公司。參數(shù)如下:燈管總長170 mm,極距140 mm,直徑6 mm;燈能量18 J,單次脈沖強度3.2 mJ/cm2,紫外區(qū)占總能量約20%,其中C波段(220~280 nm)占8%,B波段(280~ 320 nm)占4%,A波段(320~400 nm)占8%,脈沖頻率3次/s。
CT3-4500質(zhì)構(gòu)儀,美國Brookfield公司;GL-20G-II高速冷凍離心機,上海安亭科學(xué)儀器廠;754紫外-可見分光光度計,上海菁華科技儀器公司;KC/HWHS 恒溫恒濕試驗箱,上海凱測實驗設(shè)備有限公司。
1.3.1 香菇IPL處理
將當(dāng)天運回實驗室的香菇進行去柄去泥處理,隨機分成4組,其中3組分別用IPL處理9、15、21次(相當(dāng)于低、中、高強度分別為28.8、48.0、67.2 mJ/cm2),以每10個香菇為單位進行照射,處理方式為雙面照射。將處理組和對照組香菇用聚乙烯(PE)保鮮袋分裝,25 ℃恒溫保藏,每隔3 d測定相關(guān)指標(biāo),CK為無光照處理。
1.3.2 感官指標(biāo)測定
采用文獻[21]的評定方法,如表1所示。
表1 香菇感官評定指標(biāo)[21]
1.3.3 生理指標(biāo)測定
失質(zhì)量率:采用稱量法[22],以香菇在保藏過程中質(zhì)量的變化量占保藏前質(zhì)量的百分比計。
硬度:參照Ye等[23]的方法。采用質(zhì)構(gòu)儀測定,探頭直徑5 mm,將香菇菌蓋置于樣品臺上,探頭以5 mm/s的速度下壓,以2 mm/s的速度測試,以5 mm/s的速度上升,下壓深度5 mm,記錄最大穿刺力。
褐變度(browning degree, BD):參考王清章等[24]的方法,測定香菇在保藏過程中的褐變程度。
1.3.4 衰老指標(biāo)測定
過氧化物酶(peroxidase, POD)活力:根據(jù)李合生 等[25,27]的方法,以每克鮮質(zhì)量的POD活力初始每分鐘增加的0.01個光密度值為一個酶活力單位(U/min·g)。
多酚氧化酶(polyphenol oxidase, PPO)活力:參照Augustin等[26-27]的方法,以每克鮮質(zhì)量的PPO活力初始每分鐘增加的0.001個光密度值為一個酶活力單位(U/min·g)。
丙二醛(malondialdehyde, MDA)質(zhì)量分數(shù):采用硫代巴比妥酸法[28],處理后的樣液于450、532、600 nm下比色。
1.3.5 營養(yǎng)品質(zhì)測定
總酚含量:采用福林酚法,根據(jù)閆利萍等[29]提供的方法進行提取與測定。以沒食子酸作標(biāo)準品,外標(biāo)法定量。
維生素C質(zhì)量分數(shù):根據(jù)王林霞等[30]的操作,在243 nm下比色。
還原糖質(zhì)量分數(shù):采用3,5-二硝基水楊酸比色法[31],于540 nm下比色。以葡萄糖繪制標(biāo)準曲線。
1.3.6 統(tǒng)計分析
所有試驗平行測定3次,用Graphpad Prism 6.0軟件作圖,SPSS Statistics 17.0軟件進行單因素方差分析(ANOVA)及Duncan’s多重比較,<0.05表示數(shù)據(jù)間有顯著差異。
經(jīng)IPL處理后的香菇保藏于25 ℃,感官品質(zhì)的變化見表2。不同強度的IPL處理在一定程度上能延緩香菇色澤和風(fēng)味的劣變,其中28.8和67.2 mJ/cm2處理效果較好;48.0 mJ/cm2處理組的效果最佳,保藏至第6天香菇色澤和風(fēng)味均無明顯變化,第9天時仍能較好地保持其感官品質(zhì)。對照組香菇保藏6 d后即散失食用價值,而處理組香菇可基本保藏至第9 天;當(dāng)保藏至12 d時,對照組香菇干癟皺縮嚴重、褐變嚴重,有明顯霉腐味,而處理組菌褶顏色變暗,微有酸味產(chǎn)生。
表2 IPL處理對保藏期內(nèi)香菇感官品質(zhì)的影響
由圖1a可知,隨著保藏時間的延長,香菇失質(zhì)量率增加,其中前3 d失質(zhì)量尤為明顯,這主要是因為香菇采后仍進行呼吸作用和蒸騰作用,使細胞內(nèi)的游離水和水溶性成分散失,同時以二氧化碳的形式使有機物損失,導(dǎo)致失質(zhì)量率上升[4, 32]。隨后香菇失質(zhì)量率變化較緩慢,是由子實體內(nèi)細胞代謝減緩,多糖分解速率降低引起的[7],而整個保藏過程中IPL處理組香菇失質(zhì)量率均顯著低于對照組,可能是IPL處理進一步抑制了細胞代謝,減少了糖類等有機物的分解,使得失質(zhì)量率上升減緩。保藏12 d后,對照組香菇失質(zhì)量率達9.77%,而處理組均低于5%。
在各種酶的參與下,多糖、蛋白質(zhì)、果膠等物質(zhì)的降解,會引起香菇硬度降低[33]。保藏期間香菇硬度變化如圖1b所示,香菇硬度在保藏期內(nèi)逐漸降低,保藏前6 d處理組香菇的硬度與對照組無顯著差異;第9天后,對照組硬度顯著小于48.0 mJ/cm2處理組;保藏至12 d,對照組香菇硬度小于所有處理組(<0.05),但不同處理組之間無顯著差異。表明IPL處理能延緩香菇在保藏后期硬度降低,可能是因為IPL照射使香菇在保藏后期的代謝速度顯著低于對照組,在一定程度上保持硬度。
從圖1c可以看出,IPL處理后的香菇在保藏期內(nèi)能明顯減慢褐變的速度,且中、高能量效果優(yōu)于低能量。保藏前3 d,處理組香菇BD與對照組之間差異不顯著(>0.05),此后香菇BD隨保藏時間的延長不斷增加;從第6天開始,處理組BD均低于對照組(<0.05);保藏至12 d,48.0和67.2 mJ/cm2處理組BD小于28.8 mJ/cm2處理組(<0.05),且中、高強度處理組之間無明顯差異。
香菇衰老褐變與子實體內(nèi)的PPO和POD活性密切相關(guān),PPO催化各種酚類化合物氧化聚合形成黑色素,POD通過催化過氧化物亦使酚類物質(zhì)氧化[34-35]。從圖2a和2b可知,保藏前3 d,香菇POD和PPO活性均上升,本試驗香菇因經(jīng)去柄處理,存在機械損傷,可能是為了應(yīng)激該條件而引起兩者酶活力升高,同時對照組均高于處理組(<0.05)。此后各組POD活性下降,保藏9 d后,處理組POD活性均明顯低于對照組,且不同處理組間無顯著差異(>0.05),可能是IPL處理加快了蛋白質(zhì)在保藏過程中的氧化[36],故隨著保藏時間的延長酶活性降低。而處理組PPO活性在第3天后降低,對照組升至第6天后才下降;從第6天開始,48.0和67.2 mJ/cm2處理組PPO活性顯著低于28.8 mJ/cm2處理組;保藏至12 d,28.8 mJ/cm2處理組與對照組差異不明顯。說明經(jīng)IPL處理的香菇在保藏后期可使POD活性顯著下降,而有效降低保藏過程中的PPO活性需要中、高強度。
MDA作為生物樣品和食品氧化損傷標(biāo)志物,通常用其質(zhì)量分數(shù)來表征果蔬細胞脂質(zhì)過氧化程度[32]。如圖2c所見,IPL處理能延緩保藏期間香菇MDA質(zhì)量分數(shù)上升。保藏前3 d,香菇MDA質(zhì)量分數(shù)變化不明顯,此后對照組一直升高,而處理組先下降至第6天后上升;從第6天開始,處理組MDA質(zhì)量分數(shù)均顯著低于對照組,其中第9天48.0 mJ/cm2處理組最低,而第6天和第12天處理組MDA質(zhì)量分數(shù)大小順序為67.2 mJ/cm2<48.0 mJ/cm2< 28.8 mJ/cm2。
圖2 IPL處理對保藏期內(nèi)香菇衰老指標(biāo)的影響
食用菌多酚不僅與子實體褐變有關(guān),還具有抗氧化、抗病毒、降血糖、抗腫瘤及抑菌等多種生理活性[37]。由圖3a可得,保藏前3 d,香菇總酚質(zhì)量分數(shù)呈上升趨勢,可能是由于香菇子實體細胞存在組織損傷,與蛋白質(zhì)或纖維素結(jié)合的多酚在保藏初期得到釋放,且67.2 mJ/cm2處理組高于對照組(<0.05);隨后,各組總酚質(zhì)量分數(shù)降低,但IPL處理組均明顯高于對照組;保藏至12天,28.8、48.0、67.2 mJ/cm2處理組香菇總酚質(zhì)量分數(shù)比對照組分別高28.44%、42.61%、17.37%。IPL處理能延緩保藏過程中香菇總酚質(zhì)量分數(shù)的減少。
從圖3b可知,IPL處理能有效保持保藏過程中香菇維生素C的質(zhì)量分數(shù)。IPL剛處理后香菇維生素C質(zhì)量分數(shù)明顯增加。保藏前3 d,由于分解代謝及抗氧化反應(yīng)香菇維生素C質(zhì)量分數(shù)迅速下降,隨后其質(zhì)量分數(shù)波動變化,且整個保藏期內(nèi)處理組維生素C質(zhì)量分數(shù)始終高于對照組(<0.05),保藏至12 d時,28.8、48.0、67.2 mJ/cm2處理組質(zhì)量分數(shù)比對照組分別高68.56%、88.45%、63.42%。
由圖3c可知,IPL處理有利于保持保藏過程中香菇還原糖質(zhì)量分數(shù),且中、高能量效果優(yōu)于低能量。保藏前期,香菇還原糖質(zhì)量分數(shù)不斷上升,至第6天各組質(zhì)量分數(shù)達到峰值,可能是因為香菇在呼吸過程中大分子碳水化合物分解,使小分子還原糖質(zhì)量分數(shù)上升[32],也可能是失水使還原糖濃縮;此后還原糖質(zhì)量分數(shù)降低,因為后期細胞代謝減緩,多糖分解速率降低,同時作為呼吸底物不斷消耗,且48.0 mJ/cm2處理組質(zhì)量分數(shù)始終高于對照組(<0.05),并保持質(zhì)量分數(shù)最高;保藏至12天,處理組還原糖質(zhì)量分數(shù)均顯著高于對照組,且28.8、48.0和67.2 mJ/cm2處理組比對照組分別高12.87%、96.39%、54.16%。
圖3 IPL處理對保藏期內(nèi)香菇營養(yǎng)品質(zhì)的影響
在儲藏期結(jié)束時,IPL處理組香菇的保鮮效果均優(yōu)于對照組,其中67.2 mJ/cm2處理組香菇的失質(zhì)量率最小,處理組之間的硬度和POD活性無顯著差異,48.0、67.2 mJ/cm2處理組間的BD、PPO活性及MDA質(zhì)量分數(shù)無明顯差異,且均小于28.8 mJ/cm2處理組,由此看來中、高強度處理組的效果較優(yōu),且48.0 mJ/cm2處理組的總酚、維生素C和還原糖質(zhì)量分數(shù)均高于其余各處理組(<0.05),故認為本試驗中48.0 mJ/cm2處理組香菇保鮮效果最佳。
試驗結(jié)果表明,IPL處理可延緩香菇保鮮品質(zhì)下降。香菇褐變主要由于酚類物質(zhì)氧化,保藏前3 d,香菇褐變速度緩慢,該變化與總酚質(zhì)量分數(shù)改變趨勢吻合,酚類物質(zhì)的積累使酶促褐變受到抑制,子實體褐變減輕[38]。保藏中后期,香菇腐敗程度加深,總酚質(zhì)量分數(shù)降低,褐變程度增加,而IPL處理組褐變程度低于對照組(<0.05),可能是因為處理組POD、PPO活性下降的速度大于對照組,延緩了總酚質(zhì)量分數(shù)下降,也可能是IPL處理對香菇有殺菌作用,減少了微生物對子實體的侵染而引起的腐敗,從而使香菇褐變速度減慢。
維生素C和還原糖在生物體中具有重要的代謝功能和抗氧化作用[39-40],MDA在保藏前期變化不大,可能是維生素C和還原糖質(zhì)量分數(shù)在該階段的變化使總抗氧化能力抗衡,故對香菇脂膜損傷較小。在保藏后期,維生素C質(zhì)量分數(shù)出現(xiàn)波動變化,還原糖質(zhì)量分數(shù)下降,使總抗氧化能力減弱,導(dǎo)致MDA質(zhì)量分數(shù)上升。保藏后期IPL處理組香菇MDA質(zhì)量分數(shù)一直低于對照組(<0.05),可能與其子實體內(nèi)的維生素C和還原糖質(zhì)量分數(shù)變化有關(guān),其中與維生素C的關(guān)系更為密切,試驗期后階段處理組維生素C質(zhì)量分數(shù)顯著高于對照組,故處理組的抗氧化能力更好。
IPL處理在一定程度上能控制香菇采后品質(zhì),且不同能量照射對保藏期內(nèi)香菇品質(zhì)的影響存在差異,并非能量越大,保鮮效果越好。與中等能量處理組香菇比較,高能量處理組可能對營養(yǎng)品質(zhì)等存在一定破壞作用,這在保藏中、后期有所體現(xiàn),同時也受到儀器參數(shù)設(shè)置的限制,使本試驗在參數(shù)選擇方面存在一些困難。因此后期將IPL技術(shù)應(yīng)用于食用菌的品質(zhì)控制時可通過對儀器設(shè)備的改進或聯(lián)合其它保鮮技術(shù)來實現(xiàn)。本試驗后期還可對IPL處理引起香菇子實體內(nèi)各成分的變化做微觀研究,并分析它們之間的相關(guān)性,以便全面探討IPL處理對香菇采后品質(zhì)的影響及相關(guān)機制,為IPL技術(shù)在食用菌領(lǐng)域中的應(yīng)用提供理論指導(dǎo)。
1)感官品質(zhì)評定結(jié)果表明,IPL處理能較好地保持香菇的色澤和風(fēng)味,且48.8 mJ/cm2處理組的效果最優(yōu),對照組保鮮效果最差。
2)生理指標(biāo)測定結(jié)果表明,IPL處理后的香菇在保藏期間失質(zhì)量率及BD明顯低于對照組,且48.8和67.2 mJ/cm2處理組的BD顯著低于28.8 mJ/cm2處理組;在保藏后期,處理組硬度降低速度低于對照組(<0.05)。
3)衰老指標(biāo)測定結(jié)果表明,中、高強度處理組香菇在保藏過程中PPO活性低于對照組(<0.05),而各IPL處理組POD活性保藏至后期顯著低于對照組,且MDA質(zhì)量分數(shù)第6天后明顯比對照組低。
4)營養(yǎng)品質(zhì)測定結(jié)果表明,保藏6 d后處理組香菇總酚質(zhì)量分數(shù)高于對照組(<0.05),保藏至12 d時28.8、48.8和67.2 mJ/cm2處理組的總酚質(zhì)量分數(shù)比對照組分別高28.44%、42.61%、17.37%;維生素C質(zhì)量分數(shù)在整個保藏過程中均顯著高于對照組,保藏至12 d時IPL處理組質(zhì)量分數(shù)比對照組分別高68.56%、88.45%、63.42%;還原糖質(zhì)量分數(shù)在保藏期間先上升后下降,保藏結(jié)束時處理組比對照組分別高12.87%、96.39%、54.16%。
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Effects of intense pulsed light treatment with different intensity on preservation of fresh shiitake mushrooms
Qi Xiangyang, Zhou Tingting, Cao Shaoqian※
(315100,)
There is a considerable desire to maintain the nutritional compounds and sensory properties of food products which is vulnerable to traditional processing. Intense pulsed light belonging to non-thermal technology is broadly used in sterilization, enzyme inactivation because of its instantaneous, high intensity and wide spectrum light source. And it was reported in many studies that intense pulsed light could become a suitable alternative strategy to improve the food quality, but limited information exists for edible fungi. For the sake of determining the effectiveness of intense pulsed light treatment on preservation of post-harvest shiitake mushrooms, the variability of its sensory qualities, physiology and aging indices and nutrition qualities by intense pulsed light treatment with different intensity during the storage time were evaluated in this paper. For intense pulsed light treatment, the shiitake mushrooms harvested the same batch were transported back to laboratory on the same day, then removed handles and mud. The preprocessed shiitake mushrooms were divided into four groups randomly, and each was exposed to a dose of 0, 9, 15 and 21 pulses corresponding to 0, 28.8, 48.0 and 67.2 mJ·cm-2, respectively. All samples which packed with freshness protection package were stored at 25 ℃ from 0 to 12 days, while above indices were examined every three days. The results revealed that intense pulsed light treatment could maintain the colour and flavor of shiitake mushrooms to some extent, whereas the effect of 48.0 mJ·cm-2treatment group was the best that sensory qualities could retain well until 9thday of storage. Moreover, physiology indices of shiitake mushrooms including weight loss rate, firmness and browning degree deteriorated with the prolongation of storage time. At the end of preservation period (the 12thday), however, the weight loss rate of shiitake mushrooms of intense pulsed light treatment groups was all lower than 5% but the control group attained to 9.77%. The firmness of control group was significantly lower than those of treatment groups, on the contrary, the browning degree of treatment groups were lower than control group (<0.05). The intermediate and high level of intensities were lower than 28.8 mJ·cm-2, simultaneously. In addition, peroxidase activity, polyphenol oxidase activity and malondialdehyde mass fraction were associated with aging indices. Despite the peroxidase and polyphenol oxidase activity of shiitake mushrooms increased at early stage, they decreased at later period. At the end of storage time, the malondialdehyde mass fraction and the peroxidase activity treated by intense pulsed light were obviously lower than that of untreated, while the polyphenol oxidase activity of 48.0 and 67.2 mJ·cm-2groups were lower than control group (<0.05). In fact, the nutrition qualities such as total phenol and reducing sugar mass fraction of shiitake mushroom increased at preliminary and then descended during storage, vitamin C mass fraction declined. In comparison with control, the 28.8, 48.0 and 67.2 mJ·cm-2treatment groups increased respectively 28.44%, 42.61% and 17.37% for phenol mass fraction, 68.56%, 88.45% and 63.42% for vitamin C, and 12.87%, 96.39% and 54.16% for reducing sugar after 12 days of storage. Therefore, intense pulsed light could significantly retard the decrease of weight loss rate and firmness of the shiitake mushrooms, delay the increase of browning degree and malondialdehyde mass fraction, promote the reduction of peroxidase and polyphenol oxidase activity, and reduce the loss of total phenol, vitamin C and reducing sugar during the storage time. The effects of maintaining the nutrition qualities of shiitake mushrooms in 48.8 mJ·cm-2treatment group was the best. The above results indicated intense pulsed light treatment could be available for extending the preservation shelf life of shiitake mushrooms, which has a potential application prospect in controlling the qualities of edible fungi.
agricultural products; storage; quality control; intense pulsed light; shiitake mushrooms; preservation quality
10.11975/j.issn.1002-6819.2019.03.036
TS244
A
1002-6819(2019)-03-0287-07
2018-08-22
2019-01-15
浙江省重中之重學(xué)科開放基金(KF2016004); 浙江省重中之重學(xué)科學(xué)生創(chuàng)新項目(CX2017018); 寧波市自然科學(xué)基金(2018A610335)
戚向陽,教授,主要從事農(nóng)產(chǎn)品儲藏加工研究。 Email:qixiangyang85@sina.com
曹少謙,博士,副教授,主要從事農(nóng)產(chǎn)品儲藏加工研究。 Email:shaoqiancao@sina.com
戚向陽,周婷婷,曹少謙. 不同強度脈沖強光對鮮香菇保鮮效果的影響[J]. 農(nóng)業(yè)工程學(xué)報,2019,35(3):287-293. doi:10.11975/j.issn.1002-6819.2019.03.036 http://www.tcsae.org
Qi Xiangyang, Zhou Tingting, Cao Shaoqian. Effects of intense pulsed light treatment with different intensity on preservation of fresh shiitake mushrooms[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2019, 35(3): 287-293. (in Chinese with English abstract) doi:10.11975/j.issn.1002-6819.2019.03.036 http://www.tcsae.org