發(fā)布時(shí)間：2019-03-22 07:34

【摘要】：隨著科技的進(jìn)步人民生活水平的提高,人們關(guān)于食品安全越來越重視,對于食品添加劑尤為敏感。消費(fèi)者更傾向于購買不含添加劑的"純天然食品",這種趨勢推動(dòng)著新型生物保鮮劑的發(fā)展。乳酸菌本身以及乳酸菌的某些代謝產(chǎn)物具有強(qiáng)效的抑制作用,尤其是對霉菌和酵母菌最為明顯,具有成為天然防腐劑的潛質(zhì)。本論文從腐敗的乳制品、果蔬、青貯飼料中分離乳酸菌和真菌;篩選對真菌具有抗性的乳酸菌,并對抗性乳酸菌和受抑制真菌進(jìn)行鑒定;將篩選得到的優(yōu)勢菌株作為輔助發(fā)酵劑進(jìn)行酸奶防腐實(shí)驗(yàn)。結(jié)果如下:1、從實(shí)驗(yàn)材料中共分離到乳酸菌64株、真菌14株。2、通過雙層平板法和牛津杯法篩選到14株乳酸菌對3株真菌具有抑制作用。通過生物學(xué)手段對優(yōu)勢乳酸菌和真菌進(jìn)行鑒定后發(fā)現(xiàn),乳酸菌分別為植物乳桿菌、副干酪乳桿菌、鼠李糖乳桿菌、屎腸球菌;3株真菌分別為黑曲霉、白地霉、畢赤酵母。B9對黑曲霉的最大抑菌圈為21.11mm,B9對白地霉的達(dá)到17.35 mm,B10畢赤酵母的達(dá)到17.68 mm。3、將其中13株抗性乳酸菌作為輔助發(fā)酵劑進(jìn)行牛奶發(fā)酵實(shí)驗(yàn),發(fā)現(xiàn)理化特性好具有做酸奶發(fā)酵劑的乳酸菌9株;防腐實(shí)驗(yàn)中,在4℃條件下M1、B10對噴灑白地霉實(shí)驗(yàn)組的抑制時(shí)間達(dá)到28 d,B9對黑曲霉組的抑制時(shí)間為28 d,B10對畢赤酵母組的抑制時(shí)間為27 d;在常溫條件下白地霉組、黑曲霉組于168 h出現(xiàn)霉變,畢赤酵母組于144h出現(xiàn)霉變。植物乳桿菌B9、B10、M1、P10具有長貨架期酸奶發(fā)酵劑的潛質(zhì)。
[Abstract]:With the progress of science and technology, people pay more and more attention to food safety, especially sensitive to food additives. Consumers are more likely to buy additives-free "natural foods", a trend that drives the development of new biological preservatives. Lactic acid bacteria itself and some metabolites of lactic acid bacteria have strong inhibitory effect, especially on mold and yeast, which has the potential to become a natural preservative. In this paper, lactic acid bacteria and fungi were isolated from corrupt dairy products, fruits and vegetables, and silage, and the resistant lactic acid bacteria were screened, and the resistant lactic acid bacteria and inhibited fungi were identified. The selected dominant strains were used as auxiliary starter for yoghurt preservative experiment. The results were as follows: 1. A total of 64 strains of lactic acid bacteria and 14 strains of fungi were isolated from the experimental materials. 14 strains of lactic acid bacteria were screened by double-layer plate method and Oxford cup method to inhibit 3 strains of fungi. The dominant lactic acid bacteria and fungi were identified by biological means. The lactic acid bacteria were Lactobacillus plantarum, Lactobacillus paracarum, Lactobacillus rhamnosus and Enterococcus faecium, respectively. Three fungi were Aspergillus Niger, Trichoderma albicans and Pichia pastoris. The maximum inhibition zone of B9 against Aspergillus Niger was 21.11mm, and that of B9 was 17.35 mm,B10 for Pichia pastoris and 17.68 mm.3, for Pichia pastoris. Among them, 13 strains of resistant lactic acid bacteria were used as auxiliary starter for milk fermentation, and 9 strains with good physical and chemical properties were found to have good physical and chemical properties as yoghurt starter. In the anticorrosion experiment, at 4 鈩，

本文編號：2445394