Changes in Pigments and Volatiles of Saffron ( Crocus sativusL) During Processing and Storage

Significant variations were observed in the concentration of pigments (10·0–17·0%, moisture-free basis) and flavour components during different post-harvest processing conditions of saffron (stigmas ex Crocus sativus L). The crocin pigments concentration was highest (15–17%) in the saffron samples dried between 35°C and 50°C either in a solar dryer or in an oven dryer and this also resulted in considerable reduction of normal drying time. Under these conditions the main flavouring component, safranal, was at its peak value of 60% in the oil in almost all the samples except the vacuum oven dried samples which interestingly contained 4-β-hydroxysafranal in major amounts. Studies indicated that 4-β-hydroxysafranal may be an intermediate in the formation of safranal. It was observed that prolonged storage affected the pigments and flavour concentration to a great extent, but proper packaging and storage with 5% moisture in the saffron reduced the deterioration, thereby increasing the shelflife of the product.     

番红花球茎的快速高频诱导

以体外培养的脱毒番红花芽为材料,考察了外源激素及活性炭对球茎诱导的作用. 外源激素水平对球茎诱导有重要影响,较低的激素浓度下球茎诱导时间较短,较高的激素浓度下诱导出的球茎较大,但诱导时间延长. 培养基中添加活性炭后,由于活性炭的吸附作用降低了游离激素水平,显著缩短了球茎诱导时间,后期激素的缓慢释放提高了球茎质量. 在优化的1/2 MS+5 mg/L NAA+5 mg/L 6-BA+0.5 g/L AC培养基中,5周球茎诱导率高达85.7%,球茎均重0.53 g,满足移栽要求.     

利用大孔吸附树脂吸附分离藏红花细胞培养液中藏红花素和藏红花苦素

目的:研究大孔树脂提取藏红花细胞培养液中藏红花素和藏红花苦素的工艺。方法:对4种大孔树脂提取藏红花素和藏红花苦素的效果进行比较,考察HPD-100A大孔树脂提取藏红花素和藏红花苦素的最佳工艺条件。结果:HPD-100A树脂提取藏红花素和藏红花苦素效果最佳,其最适工艺条件为25℃、色素液pH6、藏红花素和藏红花苦素上样质量浓度分别为1.0mg/mL和24.6mg/mL、溶液处理量1.5BV、吸附流速1.5mL/min、洗脱剂为体积分数40%乙醇溶液、洗脱剂体积1.7BV、洗脱流速1.0mL/min。藏红花素和藏红花苦素的吸附率分别达到94.4%和75.5%,解吸率分别为99.9%和87.5%。结论:采用大孔吸附树脂吸附分离藏红花培养液中藏红花素和藏红花苦素方法可行,前景广阔。     

Equilibrium moisture content and heat of desorption of saffron

The equilibrium moisture contents of saffron (Crocus sativus L.) stigmas were determined experimentally using the standard gravimetric method at temperatures 30, 45 and 60 °C and water activity ranging from 11% to 83%. The sorption isotherm curves of saffron were sigmoidal in shape and decreased with increased temperature at constant relative humidity. Five selected isotherm models GAB, modified Henderson, modified Chung‐Pfost, modified Halsaey and modified Oswin were tested to fit the experimental isotherm data. Modified Oswin and modified Henderson models were found acceptable for predicting desorption moisture isotherms and fitting to the experimental data, respectively. The isosteric heats of desorption, determined from equilibrium data using the Clausius‐Clapeyron equation, were found to be a function of moisture content. The net isosteric heat of desorption of saffron varied between 1.38 and 5.38 kJ mol^?1 at moisture content varying between 2% and 20% (d.b).     

Sensory Threshold Studies of Picrocrocin,the Major Bitter Compound of Saffron

This study is part of a wider project on the bitter taste of saffron and its preparations. A deeper knowledge on the taste perception of picrocrocin is necessary in order to develop products that satisfy consumer senses and provide them with adequate amounts of saffron major constituents, also appreciated for bioactivity. A systematic approach on the bitterness of picrocrocin, the major responsible compound, was conducted. A panel was trained specifically for the determination of taste detection and recognition thresholds of picrocrocin, which were found to be 5.34 and 7.26 mg/L, respectively, using the Ascending Forced Choice of Limits methodology. The threshold values were examined in water in absence and presence of other saffron constituents and ethanol and were found to decrease when served hot (61 ± 4 °C). Bitterness was enhanced in 40% (v/v) aqueous ethanol. In both aqueous and ethanol extracts, the presence of saffron volatiles improved bitterness perception. The usefulness of the study was tested in the case of commercial saffron based infusions.     

Effect of mother corm dimension and sowing time on stigma yield,daughter corms and qualitative aspects of saffron (Crocus sativus L.) in a Mediterranean environment

BACKGROUND: Saffron is one of the most appreciated and expensive spices known and has been used from the oldest times as a dye for fabrics, a condiment to enrich food and for medicinal purposes. The aim of this study was to evaluate the effect of crop management methods on the quantitative and qualitative characteristics of the spice in southern Italy. Two sowing times (end of July and end of August) and two corm dimensions (4 and 3 cm horizontal diameter) were evaluated. RESULTS: Flowering period and duration were not influenced by the studied factors, while early sowing time and greater corm dimension resulted in a greater number of flowers per m², increased stigma yield and a greater total yield of replacement corms. Early sowing time also showed a significant positive influence on stigma quality measured as apocarotenoid content according to ISO guidelines. CONCLUSION: The results show that, in a Mediterranean environment, appropriate crop techniques and selection of corms can result in economic levels of production and improve the quantitative and qualitative characteristics of saffron. In fact, according to their apocarotenoid contents, samples from the early (July) and late (August) sowing times belonged to the first and second ISO categories respectively. Copyright © 2008 Society of Chemical Industry     

植物乳杆菌L-YL发酵藏红花芦笋复合饮品的研制

以含多种活性成分的藏红花、芦笋为主要原料,采用植物乳杆菌（Lactobacillus plantarum）L-YL进行发酵,研制了一款益生乳酸菌发酵的藏红花、芦笋活菌型复合饮品。通过单因素试验、最陡爬坡试验、响应面试验对发酵复合饮品配方进行优化并验证,得出最佳配方为：藏红花、芦笋粉含量2.50%,酵母粉20.8 g/L,葡萄糖10.0 g/L,乙酸钠1.5 g/L;同时测得复合饮品中植物乳杆菌L-YL活菌数可达7.50×108 CFU/mL,多糖含量23.36 mg/mL,总黄酮含量为0.24 mg/mL,研制出了一款具有开发潜力的益生菌发酵复合饮品。