【作者】 郁志芳；

【导师】 陆兆新；

【作者基本信息】 南京农业大学 ， 食品科学， 2005， 博士

【摘要】 鲜切果蔬产品的新鲜、洁净、卫生和方便等特点使其在发达国家发展迅速，引起园艺学家、食品科技家、企业家、投资者、消费者、政府官员等的高度重视和关注，已成为果蔬采后发展的新领域。鲜切果蔬因经过切分、清洗等处理，产品的品质下降快、生理生化代谢迅速、易受到微生物侵染、产品的保质期短。国内外有关鲜切果蔬研究的内容主要包括原料学（适宜的种类、品种、原料品质要求等）、生物学（呼吸、乙烯、次生物质代谢、酶促反应、水分生理和控制等，伤响应的机理）、微生物学（微生物污染源、种类、数量和预测模型等）、品质及评价（颜色、风味、芳香和质地等品质因子的客观和主观评价等）、加工工艺学（清洗、切分、保鲜处理和包装等）、安全性和质量保证（HACCP认证）等。 芦蒿作为健康、天然、绿色野生蔬菜的代表由于颜色鲜绿、组织脆嫩、气味清香、风味鲜美、营养丰富已成为南京乃至江苏特色的野生蔬菜新品种，其适合鲜切菜生产，但极易发生褐变等，造成品质的急剧下降。本研究旨在通过对鲜切芦蒿品质变化和褐变特性的探索，揭示其品质变化的规律和褐变机理。主要研究结果如下： 新鲜青杆芦蒿去除叶片、茎尖和纤维化的等不可食部分、冰水清洗、切分（2.5～3.0cm）后，测定水分、蛋白质、脂肪、可溶性固形物、灰分、Vc、膳食纤维和硒的含量。结果显示芦蒿组织的蛋白质、灰分、膳食纤维等含量丰富，且含人体必需有的硒；另外，发育程度较高的芦蒿除水分和Vc外，蛋白质、脂肪、可溶性固形物、灰分、膳食纤维和硒的含量均显著高于发育程度低（幼嫩）的芦蒿。 采用薄层层析、光谱扫描和HPLC光谱分析等方法对芦蒿酚的种类进行初步鉴定，结果表明鲜切芦蒿中的主要酚类物质是绿原酸。 鲜切芦蒿4±0.5℃贮藏期间S.S.含量逐渐增加、还原糖含量稳定下降；冷藏15天后Vc损失很少，仅为0.35mg.100g^-1FW；叶绿素含量有所减少（＜15％），叶绿素酶活力呈稳定增加趋势，两者呈显著负相关（r=-0.994）；纤维素含量贮藏15天后是入贮时的137.7％，增加明显，而纤维素酶活力贮藏结束时仅为入贮时的7％。鲜切芦蒿呼吸作用旺盛，冷藏后期显著增强，达到入贮时的两倍。MDA和O₂^-含量及BD均随贮藏时间延长而增加，O₂^-含量第9天后增加显著。 TP和FP的定量分析显示：鲜切芦蒿中TP含量较高，可达到近12ug.g^-1FW以上，提示其具有较强的褐变可能；鲜切芦蒿FP占TP的比例小于35％，表明鲜切芦蒿中更多还原

【Abstract】 Owing to the freshness, convenience and cleanness, freshcut fruit and vegetables have been developed very fast in industrial countries, and many horticulturists, food scientists and engineers, business man, investors, consumers and as well as governors have been drawn much attention into it. Freshcut has now become a new postharvest area of horticultural crops. Due to cutting and cleaning processes, freshcut fruit and vegetables lose their quality quickly, companied with rapid biological reactions, are easy to be contaminated by microbes, and therefore have only about 1 week shelf life. Worldwide researches recently worked on freshcut fruit and vegetables mainly include following aspects: raw materials requirements (species and cultivars of fruit and vegetable, minimal quality requirements and so on), biology (respiration, ethylence, secondary metabolism, enzyme activity and change, water loss, and control; mechanism of damage response, ect.), microbiology (sources of contamination, species and their quantity, prediction model, ect.), product quality and evaluation (quality indices, methods of, and son on), processing techniques (cleaning, cutting, packaging, ect.), food safety and quality control (HACCP certification). Browning mechanism and its control especially get people’s attention.As a healthy, natural and green wild vegetable, Artemisia selengensis with the characteristics of green color, crisp texture, attractive aroma, delicious flavor, and rich in nutrients has already become a representative vegetable in Nanjing and even in Jiangsu province. Although Artemisia selengensis is suitable to be processed into freshcut product, browning is such a severe problem that results in quality loss dramatically during processing. This thesis touched the quality change and browning property of Artemisia selengensis after cutting and during storage in order to obtain that how the quality of freshcut Artemisia selengensis is changed, what browning especially enzymatic browning mechanism is and how we could control it. The main research results are as following:The edible stems of Artemisia selengensis after removed leaves, sprout and fiberizated parts, cleaned in ice water were cut into the length of 2.5-3.0 cm. The contents of water, protein, fat, soluble solids (S.S.), ash, Vc, edible fiber and Se were determined. The results showed that the edible stems of Artemisia selengensis were rich in protein, ash and edible更多还原