【作者】 胡新中；

【导师】 魏益民； Fregeau-Reid Judith； Zhou Jian-qiang；

【作者基本信息】 西北农林科技大学 ， 食品科学， 2007， 博士

【摘要】 【目的】解决裸燕麦食品加工中脂肪氧化酶的氧化和裸燕麦加工食品过程中脂肪酶的抑制工艺问题,【方法】本研究以影响燕麦加工的关键点(酶活性、脱皮制米、口感改良)为突破口,采用VAO-2等裸燕麦品种,对燕麦籽粒中脂肪酶的分布,红外烘烤、普通烘烤、常压蒸制、加压蒸制处理对裸燕麦、燕麦米酶活性的灭酶效果进行了比较,并在此基础上开展了燕麦食品开发研究。【结果】研究认为,红外灭酶处理的燕麦产品酶活性被完全抑制,口感得到改善,解决了制约燕麦食品开发的技术难题,为促使燕麦成为未来主粮奠定了理论基础。【结论】通过研究,得到以下结论:1.对燕麦中脂肪酶活性分布的研究表明:脂肪酶活性与燕麦籽粒长度、面积、千粒重、籽粒宽度呈极显著负相关,与单位重量籽粒面积呈极显著正相关。籽粒越大,脂肪酶活性越低。脂肪酶活性与去皮率、脂肪含量分别呈负相关(r=-0.910***、-0.650*)。去皮20s获得的燕麦米白度最佳,β-葡聚糖、蛋白质含量损失较少。所以,采用佐竹制米机去皮20s作为燕麦米制作的最佳工艺。这一结论为燕麦籽粒和燕麦米酶活性抑制提供了理论支持。2.不同灭酶处理的灭酶效果表明:普通蒸制、高压蒸制、红外烘烤能完全杀死裸燕麦脂肪酶和过氧化氢酶,普通烘烤不能杀死这些酶。红外烘烤前润麦水分十分重要,20%的润麦水分对于不同的燕麦品种均适合,18%的润麦水分不能有效杀死燕麦的脂肪酶和过氧化酶。籽粒大小对于红外灭酶也有很大影响,小籽粒(平均粒重18.4mg)比混合籽粒(平均粒重23.7mg)灭酶困难。用红外进行灭酶,需要保温6h,才能获得可靠的灭酶效果。红外烘烤处理的籽粒品质兼备蒸制和烘烤的优点,加工时间短(18s),是一种理想的燕麦加工工艺。3.燕麦米灭酶试验结果表明:常压蒸制、高压蒸制、红外烘烤能杀死酶,普通烘烤未能抑制燕麦米酶活性。润麦时间对于灭酶效果影响很大,润麦时间需要控制在3h以内,延长润麦时间导致酶不能被杀死。烘烤后需要保温6h,以获得彻底的灭酶效果。这些数据为燕麦米制品开发奠定了基础。4.对不同灭酶处理籽粒进行扫描电镜和光学显微镜观察发现:蒸制处理的燕麦淀粉颗粒开始糊化,相互形成粘连。红外烘烤的燕麦淀粉分子从颗粒中分裂出来。峰值粘度大小顺序为常压蒸制燕麦、加压蒸制燕麦、红外烘烤燕麦、普通烘烤燕麦,粘度均高于燕麦对照。β-葡聚糖是组成燕麦细胞的骨架,脂肪主要分布于籽粒皮层和胚芽。不同加工方式对于β-葡聚糖、脂肪影响不大。这为燕麦酶活性效果评价和品质变化提供了分析依据。5.燕麦食品加工特性研究结果表明:与小麦面粉相比,燕麦蛋白质组分中清蛋白、醇溶蛋白含量较低,球蛋白含量高,谷蛋白含量较低。燕麦粉峰值、最大、最终粘度均小于对照小麦面粉。加入燕麦粉后,混粉面团形成时间延长,稳定时间降低。当小麦面粉取代量大于5%时,混粉食品制作品质有显著变化。加入10%、25%、10%燕麦粉制作面条、馒头和面包是较为理想的配比。在主食原料中添加燕麦粉是解决燕麦成为未来主粮的重要食品加工方法。谷朊粉对燕麦全粉面包制作影响最大;沙蒿籽粉对燕麦全粉馒头制作影响最大;沙蒿和谷朊粉共同使用的效果大于两者单独使用;加入2.5%沙蒿和8%谷朊粉对燕麦全粉面包和馒头品质改善效果最好。对冷冻面团加工而言,冷冻时间对燕麦全粉面包体积和总评分有极显著影响;对燕麦全粉馒头体积和总评分的影响高度显著。以沙蒿籽粉和谷朊粉作为绿色品质改良剂可以显著改善燕麦全粉食品的加工品质。6.燕麦米、燕麦粉加工品质表明:以1/3的燕麦米与2/3大米混合开发燕麦米制品,以1/3燕麦粉与2/3小麦粉混合开发燕麦面制品。小麦:大米:燕麦=2/3:2/3:2/3,小麦、大米、燕麦三分天下,形成了燕麦作为未来主粮的战略框架。添加10%、20%红外烘烤燕麦全粉制作的面包体积(1175ml、1075ml)与小麦粉对照面包体积(1120ml)大小相当。加入10%、20%、30%燕麦米制作的燕麦米饭的感官评分差异不大,但燕麦米饭的口感与纯大米饭相差不大。使用红外烘烤工艺处理裸燕麦、燕麦米对于推动燕麦成为未来主粮提供了方法支持和理论依据。更多还原

【Abstract】 To solve the problems that the obstacles affected naked oats (Avena nuda) for food processing in China, this research focus on the key facors, which as enzyme activity, debranned for oat rice, mouthfeel improvement, and oat processing releated factors as breakthrough point, the naked oats varieties VAO-2 and others were used to compare the enzyme distribution, enzyme deactivation, and developed the oat-rice, oat-wheat flour for staple food processing. The purpose was to push the oats as the future staple food crops followed by rice and wheat.The results showed that micronizing was a very good method for enzyme deactivation, at the same time, the oat food mouth feel was improved, and the technology obstacle which limiting oat food development had been removed, it would be the basic knowledge for pushing the oat as the future staple food.1. The results releated with lipase enzyme distribution showed: lipase activity had positively significantly correlated with kernel length, width, areas, and one thousand kernel weight, but negatively related with ratio of kernel weight divided by area. The bigger the kernel, the lower the lipase activity was. Lipase activity was negatively correlated with oat debran ratio, and lipid content. The oat rice got after 20s debran was higher in kernel whiteness, lower loss ofβ-glucan, and proten content. 20s debran with Japan Satake mill was selected by the best technology as oat rice development. It provided the basic foundament for naked oat kernel and oat rice enzyme deactivation.2. The results from different enzyme deactivation methods showed: normal pressure steaming, autoclaving, and micronizing can kill the lipase and peroxidase of naked oats, dry roasting can’t deactivated these enzymes. The tempring content was very important for micronizing, 20% moisture was the deadline for deactivation, and 18% tempering moisture content didn’t work. Kernel size was another key factor affected micronizing results. Small kernel (average single kernel weight 18.4mg) was diffculty to get the exactly deactivation results than mixed kernel (average single kernel weight 23.7mg). The third key factor for micronizing is temperure keeping after micronzing; 6h was minimum period for totally deactivation. Micronzing was a very good technology for oat processing, it combined the roasting and steaming technology together, and work time was very short until 18s. 3. The results for oat-rice deactivation showed: normal pressure steaming, autoclaving, and micronizing can deactivate the lipase and peroxidase of naked oats, dry roasting can’t kill these enzymes. Tempering time was greatly affected the enzyme deactivation, longer than 3h will make some enzyme couldn’t be killed. Also, temperature keeping for 6h was another important index for enzyme evulation. It prepared the stong basic knowledge for oat rice food development.4. The scanning electronic microscopy and florense microscopy photo for treated oats kernel showed: The starch granule had been gelatinized and sticked together after steaming and autoclaving. The starch had been broken out from micronized oats kernel. The sequence of peak viscosity for oat kernel from high to low was normal steaming, autoclaving, micronzing, normal roasting, and then naked oats check.β-glucan was the main bidge for oat cell connection. Lipid was mostly distributed along the kernel out-bran and germ. The enzyme treatment had no significantly effect for the lipid, andβ-glucan content. It provided the evulation methods for enzyme deactivation and quality change.5. The results related oat food processing was: Compared with wheat flour, oat flour has lower albumin, gliadian content, higher globulin content, and a little lower in glutenin content. The oat flour has higher peak viscosity, maximum viscosity and final viscosity than wheat flour. The wheat flour dough mixed oat flour had longer dough development time, but shorter stability time. Substituted the oat flour with the same proportion wheat starch, the specific volume and sensory evaluation score of bread and steam bread reduced, the noodle water absorption and total evaluation score reduce but water loss increase. The starch has significantly effects for food quality index when substitution level higher than 5%.The best oat flour mixture proportion for noodle, steam bread and bread making was 10%, 25% and 10%. It would be the important method for pusing the oat as the future staple food. The effects of Artemisia sphaerocerphala kraschen (or ASK) and vital gluten for oat products processing quality was: The vital gluten was the biggest effect to bread processing. The ASK was the biggest effect to steam bread making. The combined effect of the ASK and vital gluten is greater than their single effect. The best formula of oat whole meal bread and steam bread is 2.5% ASK and 8.0% vital gluten. For frozen dough processing, freezing time has significantly effect to bread volume and sensory score, and significantly to steam-bread volume and sensory score. The quality of the frozen dough decreased gradually with the time passed, the oat whole meal processing quality of bread and steamed bread became worse 4 days later. The ASK and vital gluten can be used as the nature improver for oat whole meal food processing.6. The results related oat-rice and oat-wheat flour processing quality was: Combined 1/3 of the oat with 2/3 of rice could be used to develop oat-rice products, combined 1/3 of the oat flour with 2/3 of wheat flour for oat-wheat flour products development. The ratio between wheat: rice: oat = 2/3: 2/3: 2/3, the wheat, rice, and oat was equal and all of them came to the table as the same amout, and satisfied with our proposal of“oat as third staple food”. 10%, and 20% deactivation oat flour blended with 90% and 80% wheat flour can be processed good quality bread, and their bread volume had no significantly difference. Seneory evaluation score of oat-rice as the proportion 10%, 20%, and 30% of oat mixed with rice had no significantly difference.Naked oats and oat rice combined with the micronzing technology provided the basic principle and protocol to develop the proposal of oat as future staple food.更多还原