枇杷果醋及其饮料的研制

以枇杷鲜果为原料，通过对比试验和正交试验，确定生产工艺和枇杷果醋饮料的原料优化配比。结果表明，酿造工艺条件为枇杷果汁糖度调整至14％，接入0．3％酒用活化酵母，酒精发酵温度28℃～32℃，酒精发酵时间约8d；枇杷酒液酒精度调整至7％，接入10％醋酸菌，醋酸发酵温度36℃～38℃，醋酸发酵时间约10d。枇杷果醋饮料调制的优化参数为酸度5．5％的枇杷果醋8．0％，枇杷果汁15％，蜂蜜7．0％，有机酸（柠檬酸：苹果酸=2：1）0．08％，在25MPa压力下均质处理。酿制的枇杷果醋具有食醋清香和枇杷果香，酸味柔和，风味独特：调制的枇杷果醋饮料澄清透明，酸甜爽口，枇杷果香浓郁。     

低醇菠萝果酒酿造工艺的研究

用发酵法生产低醇优质菠萝果酒，对4种果酒专用的酿酒酵母进行了对比试验，确定选用最适合菠萝酒酿造的酵母菌株Y19：同时对影响菠萝果酒品质的重要工艺参数进行了探讨，确定菠萝果酒酿造最佳含糖量为20％，主发酵温度20℃，发酵时间7d，添加偏重亚硫酸钾110mg／L。经过成分调配、澄清、陈酿等工艺得到酒精含量为10％（v／v），糖含量为45g/L的优质、低醇甜型菠萝果酒。     

豆梨发酵果酒工艺研究

研究豆梨发酵酒酿造工艺和参数.以豆梨果浆为原料,经过主发酵、后发酵和澄清等工艺酿制成发酵酒.采用单因素试验和正交试验,研究适宜豆梨酒发酵的料水比、糖度、酵母接种量、发酵温度和发酵时间.结果表明,豆梨酒主发酵最佳工艺为:料水比1∶2、糖度25％、0.03％果酒专用酵母、发酵温度25℃.豆梨酒适宜的后发酵温度为15℃、发酵期为20d.成品酒呈宝石红色、酒度较高与透亮诱人,且色、香、味俱佳与具有独特的豆梨酒风格.     

杨桃果酒生产工艺研究

以香蜜杨桃为主要原料，研究杨桃果酒的生产工艺。结果表明，杨桃果酒生产工艺为采用除渣发酵，SO2添加量45～60mg／L，添加果胶酶0．6％，酶解温度15℃，接种法国酵母，主发酵温度控制20℃。     

枇杷果酒的护色工艺研究

对枇杷果酒加工过程中的护色工艺进行了研究。在发酵前添加抗坏血酸和柠檬酸，结合一定温度和一定时间的热处理等工艺，有利于枇杷果酒的护色，防止褐变。结果表明，抗坏血酸添加量为0．7g，kg，热处理温度为80℃，热处理时间为20min，柠檬酸添加量为0．5g/kg，能有效解决枇杷果酒生产过程中色泽加深问题。     

枇杷果酒的酵母菌株筛选及工艺优化

对 4个不同酵母菌株在 1 7℃、2 5℃下采用 1次和 2次加糖工艺发酵酿造枇杷果酒 ,研究了各菌株的发酵速率和产酒能力 ,并对枇杷果酒质量进行感官综合模糊评判。试验表明 ,以 2 #菌株在 2 5℃左右下 ,采用 2次加糖发酵工艺 ,酿制出的果酒质量最好。低温 ( 1 7℃ )发酵 ,以选择1 45 0 #菌株为宜 ,其发酵速率快 ,发酵能力强 ,酿制出的果酒质量较好。     

中心组合和响应面分析优化枇杷果酒发酵工艺

以浙江省余杭县塘柄枇杷为原料,研究枇杷果酒的发酵工艺.考察了果胶酶添加量对出汁率的影响,然后在糖浓度、接种晕和主酵温度对枇杷酒发酵重要指标及风味影响的单因素试验的基础上,通过中心组合试验设计和响应面分析优化获得最佳发酵工艺.最佳生产工艺:糖浓度22°Bx,接种量0.55g/L,发酵温度23.09℃,果胶酶添加量120mg/L,终产品酒精含量12.1%vol～12.8%vol,总糖6.76g/L,总酯0.73g/L,总酸8.96g/L,产品金色澄清透亮,枇杷香气浓郁.本实验的酿造工艺,能保证枇杷果酒的品质,具有中试放大的潜力.     

玫瑰茄桑葚复合果酒酿造工艺的研究

以桑葚和玫瑰茄为主要原料,研究采用控温发酵技术酿造玫瑰茄桑葚复合果酒的工艺流程,根据单因素试验结果,采用L9(34)正交组合设计,确定最佳工艺参数为:桑葚汁和1%玫瑰茄提取液质量比为2∶3,SO2添加量为60 mg/L,发酵温度为26℃,酵母接种量为0.03%,初始糖度调整为20%,主发酵时间为10 d。在此条件下酿造,可得到色泽好、风味佳、酒度适中的水果型玫瑰茄桑葚复合果酒。     

晌应面法优化沙棘果酒发酵条件的研究

以沙棘汁为原料,自选酵母菌Y23作为菌种进行发酵,通过单因素试验选取温度、SO2用量、接种量、发酵时间为主要因素,根据Box-Benhnken中心组合试验设计原理,采用响应面分析法确定沙棘果酒最优发酵工艺条件。结果表明：沙棘果酒发酵最佳工艺条件为：温度28．4℃、SO2用量88mg／L、接种量12％、发酵时间9．5d,在此条件下沙棘果酒的酒精度为（11．2±0．2）％（V：V）。     

青梅果酒酵母的筛选与发酵工艺优化

选取11株耐受性较好的果酒酵母对青梅果酒进行发酵试验,以酒精度、总酸和感官指标为考察参数,筛选出1株发酵能力强,所酿造果酒品质好的为最优菌株。通过研究果实成熟度、酵母添加量、主发酵温度对青梅果酒品质的影响,确定青梅果酒的最佳酿造工艺参数。优化后的青梅果酒发酵工艺条件为:青梅果实成熟度为8~9成;酵母接种量为0.3 g/L;主发酵温度为20℃。在此条件下进行3.5 t发酵罐的生产试验,发酵过程稳定,所得的青梅果酒酒精度为13.9%vol±0.3%vol,残糖量为0.97 g/L±0.21 g/L,总酸含量为37.42 g/L±1.48 g/L,干浸出物含量为51.36 g/L±1.24 g/L。     

Sugar metabolism in relation to chilling tolerance of loquat fruit

The relationship between chilling injury and sugar metabolism was investigated in loquat fruit stored at 1 °C for 35 days. No symptoms of chilling injury occurred in the fruit, of ‘Ninghaibai’ cultivar, during the whole storage whereas, in ‘Dahongpao’ fruit, severe chilling symptoms were observed after 20 days of storage at 1 °C. ‘Ninghaibai’ fruit had higher levels of glucose and fructose and higher activities of sucrose hydrolyzing enzymes, such as sucrose synthase-cleavage and invertase, than had ‘Dahongpao’. Furthermore, the chilling resistant ‘Ninghaibai’ fruit also showed higher activities of hexokinase and fructokinase, involved in hexose phoshorylation and sugar signal generation. These results suggest that the higher content of hexoses and activities of hexose sensors were likely part of the mechanism for chilling tolerance of loquat fruit.     

枇杷果酒酿造工艺研究

以四川成都龙泉枇杷为原料研究了枇杷果酒的加工工艺,并探讨了不同发酵温度、糖浓度对果酒质量的影响.结果表明,发酵温度和糖浓度对酒的品质有比较明显的影响.     

Some physicochemical properties and mineral contents of stirred yoghurts containing different fruit marmalades

In this study chemical properties and mineral levels of yoghurts containing different fruit marmalades were investigated. Cherry laurel, loquat fruit and kiwi marmalade were used to make the stirred yoghurts, and the calcium, phosphorus, sodium, magnesium, manganese, iron, zinc, copper, boron, lead, nickel, molybdenum, chromium, cadmium, cobalt levels were determined by an inductively coupled plasma optical emission spectrometer (ICP–OES). The total solid, fat, ash, pH, viscosity and syneresis contents of the yoghurt samples changed between 13.85–21.02%, 2.45–2.90%, 0.82–0.94%, 4.11–4.22, 2104–2454 cP and 42.0–47.0 mL/100 g, respectively. The mean concentrations in the yoghurts of these minerals were 104.66–118.94 calcium, 95.81–112.42 phosphorus and 13.47–15.04 magnesium as mg/100 g, 235.00–254.00 iron, 429.00–453.00 zinc and 70.45–122.90 copper as μg/100 g. The recommended dietary allowance (RDA) was calculated on the basis of the intake of one yoghurt portion (125 g).     

Fatty acid composition and antioxidant system in relation to susceptibility of loquat fruit to chilling injury

Two cultivars of loquat fruit with contrasting chilling resistance were stored at 1 °C for 35 days to investigate the relationship between chilling injury and fatty acid composition and its antioxidant system. No symptoms of chilling injury occurred in the fruit of ‘Qingzhong’ cultivar during the whole storage, whereas in ‘Fuyang’ fruit, chilling injury increased sharply after 21 days of storage at 1 °C. ‘Qingzhong’ fruit had lower levels of superoxide radical and H₂O₂, in addition to lower lipoxygenase activity, but higher membrane lipid unsaturation and higher activities of superoxide dismutase and catalase than ‘Fuyang’. Furthermore, the chilling resistant ‘Qingzhong’ fruit also showed higher activities of antioxidant enzymes involved in ascorbate–glutathione cycle and higher levels of ascorbate acid and reduced glutathione. These results suggest that the higher membrane lipid unsaturation and the more efficient antioxidant system were both beneficial in enhancing resistance of loquat fruit to chilling injury.     

Effect of methyl jasmonate on cell wall modification of loquat fruit in relation to chilling injury after harvest

Loquat fruit were pretreated with 10 μM methyl jasmonate (MeJA) for 24 h at 20 °C, and then stored at 1 °C for 35 days to investigate the effect of MeJA treatment on cell wall modification in relation to chilling injury. Loquat fruit developed chilling injury, manifested as increased fruit firmness and internal browning, decreased extractable juice during storage. These chilling injury symptoms were significantly reduced by MeJA treatment. MeJA also markedly delayed the increases in lignin, alcohol insoluble residues, hemicellulose and cellulose. Meanwhile, the MeJA-treated fruit exhibited significantly lower activities of phenylalanine ammonia lyase, peroxidase, polyphenol oxidase and higher polygalacturonase activity than the control during storage. The levels of water- and CDTA-soluble pectins in MeJA-treated fruit were also significantly higher than that in the control. These results suggest that the reduction in chilling injury by MeJA may be due to inhibited lignin accumulation and enhanced cell wall polysaccharides solubilisation.     

MeJA induces chilling tolerance in loquat fruit by regulating proline and γ-aminobutyric acid contents

Loquat fruit were pretreated with 10 μmol l⁻¹ methyl jasmonate (MeJA) for 24 h at 20 °C and then stored at 1 °C for 35 days to investigate the effect of MeJA treatment on chilling injury (CI) and changes in the contents of proline and γ-aminobutyric acid (GABA). The control fruit exhibited severe flesh leatheriness, a specific CI symptom, after 21 days of storage at 1 °C, but it was reduced in MeJA-treated fruit. During the development of CI in fruit, proline and GABA accumulated with the storage time, while MeJA treatment enhanced the increases in proline and GABA contents. The MeJA-treated fruit exhibited higher activities of Δ¹-pyrroline-5-carboxylate synthetase (P5CS), ornithine δ-aminotransferase (OAT) and glutamate decarboxylase (GAD), and lower proline dehydrogenase (PDH) activity than control during storage. These results suggest that the reduction in CI in loquat fruit by MeJA may be due to the increased proline and GABA contents.     

"大五星"枇杷冷藏过程中采后生理特性的研究

在4℃、8℃和12℃3种低温条件下冷藏"大五星"枇杷,检测其采后呼吸强度、硬度、细胞膜透性、丙二醛含量、PAL活性及自由基清除酶(POD、CAT和SOD)活性等指标的变化.结果表明8℃是"大五星"枇杷果实适宜的贮藏温度,4℃以下枇杷果实易发生冷害.在贮藏的过程中,枇杷果实呼吸强度一直呈递减的趋势,直到果实发生大量的腐烂也未见呼吸高峰.在8℃、12℃和常温下贮藏,果实的硬度、果皮的细胞膜透性、丙二醛(MAD)含量、苯丙氨酸解氨酶(PAL)活性和过氧化物酶(POD)活性均呈上升趋势;过氧化氢酶(CAT)活性和超氧化物歧化酶(SOD)活性呈下降趋势.果实的MAD含量与相对电导率、细胞膜透性呈显著正相关.在4℃贮藏温度条件下,从12d开始,果实硬度、果皮的细胞膜透性、MAD含量和PAL活性都明显高于其它3个温度条件下相同贮藏时间的果实,而自由基清除酶(CAT、POD及SOD)的活性相对比其它3种温度条件下贮藏的果实低.     

枇杷薄膜包装贮藏效果研究

采后大红袍枇杷果帝用０．０１￣０．０３ｍｍ厚聚乙烯薄膜密封包装结合１℃低温贮藏,可显著抑制果实失水,延缓果实可溶性固形物（ＴＳＳ）、可滴定酸（ＴＡ）和ＶＣ下降,保持果帝新鲜外观和品质,而对果实腐烂无显著影响,查实贮藏期可达２０ｄ以上,薄膜密封包装在２０℃高温下贮藏,虽可有效抑制果实伯水,但促进果实发生,这与包装袋内ＣＯ２和Ｃ２Ｈ４积累,从而促进果帝的衰老和导致果实的生理失调有关。     

枇杷果酒的工艺研究

以枇杷为主要原料,制汁后以活性干酵母发酵来制得枇杷果酒,对发酵工艺条件、澄清和调配进行了研究,结果表明,最佳发酵条件为:温度25℃、接种量0.5%、SO2添加量80mg/L、初始pH值4.0,在发酵8d后,残糖量和酒度基本不再变化,可终止发酵;添加0.10%的皂土进行澄清效果较好,生成沉淀多;发酵酒原液添加白砂糖3%、蜂蜜0.2%、苹果酸0.1%、柠檬酸0.2%进行调配后,得到的枇杷酒甜酸适口、风味较好。