浅谈冰荔枝酒的生产工艺

介绍了以广东省郁南县成熟荔枝为原料,将鲜荔枝破碎后,经酶解浸渍、果汁澄清、冷冻浓缩、低温发酵、陈酿、调配等工艺酿造出甘甜醇厚、酸甜协调、回味悠长,酒体丰满具有浓郁荔枝果香优质冰荔枝酒。最佳的工艺参数为：酵母加入量为1.5g/L,发酵温度13℃,酒度15%vol～16%vol,总糖260～280g/L,总酸4g/L。     

几种澄清剂对冰荔枝酒澄清效果的比较研究

研究了单一澄清皂土、蛋清粉和复合澄清剂皂土与明胶对冰荔枝酒的澄清效果,并通过正交试验及综合评比分析,结果表明复合澄清剂皂土与明胶的澄清效果明显好于单一澄清剂,经皂土与明胶处理的冰荔枝酒透光率达99.8%,组成了最佳澄清工艺条件:皂土用量0.6g/L,明胶用量0.10g/L,澄清后的冰荔枝酒澄清透明,稳定性增加。     

Effects of spontaneous and inoculated fermentation on the volatile profile of lychee (Litchi chinensis Sonn) fermented beverages

The aim of this study was to evaluate the contribution of yeast to the volatile profile of beverages obtained by the fermentation of lychee must through inoculated (Saccharomyces cerevisiae strains UFLA CA116 , UFLA CA1183 and UFLA CA1174 ) and spontaneous fermentation. Higher alcohols and esters were the primary volatiles detected by SPME/GC–MS. A Principal Component Analysis indicated similarities between UFLA CA116 and UFLA CA1183 and between UFLA CA1174 and spontaneous fermentation. Changing the yeast strain used in the fermentation process has the potential to modulate the volatile profile of fermented beverages. The beverage produced by the inoculation of yeast CA1183 showed the most complex aroma profile compared to the other beverages.     

影响干白荔枝酒发酵的因素及控制方法

干白荔枝酒发酵的主要环节是酵母将糖转化为酒精和CO2.影响干白荔枝酒发酵的主要因素是酵母菌种、适宜酵母发酵的果汁成分、SO2含量以及发酵温度、发酵条件及贮藏条件等.研究结果表明,酵母菌种采用葡萄酒酵母(S.ellipsoideus),果汁含糖量为15～17 Bx°,SO2含量为60 mg/L,发酵温度控制在16～18℃为佳.     

Effects of branched‐chain amino acid addition on chemical constituents in lychee wine fermented with Saccharomyces cerevisiae

This study investigated the impact of single branched‐chain amino acid addition (L‐valine, L‐leucine, L‐isoleucine) on nonvolatile and volatile constituents in lychee wine fermented with Saccharomyces cerevisiae MERIT.ferm. The individual addition of branched‐chain amino acids decreased the consumption of proline with significantly different rates. The lychee wine with added L‐leucine and L‐isoleucine had higher odour activity values (OAVs) of isoamyl alcohol, active amyl alcohol and isoamyl acetate. The lychee wine with added L‐valine had higher OAVs of isobutyric acid and isobutyl alcohol (5.55 and 2.98, respectively), which were lower in the wine with added L‐leucine (2.91 and 1.02, respectively) or L‐isoleucine (3.43 and 1.73, respectively) relative to the control wine (4.18 and 1.77, respectively), suggesting interactive effects among the amino acids. These findings demonstrated that lychee wine aroma can potentially be manipulated via the addition of selected branched‐chain amino acids.     

Effect of two drying methods on antioxidant activity and hypoglycemic action of polysaccharides in three cultivars of lychee pulp

Effect of air drying and freeze drying on polysaccharides of lychee with three cultivars was determined in terms of polysaccharides yield, antioxidant capacity and hypoglycemic action. The results show that Guiwei lychee pulp had the highest crude polysaccharide yield among three lychees. However, Feizixiao lychee had the lowest EC₅₀ concentration and the highest FRAP (Ferric reducing antioxidant power) value. Moreover, Guiwei lychees dried by air drying had the best effect for improving glucose tolerance of normal mice and diabetic mice. Three freeze dried lychees had no significant effect. The effect of air dried Guiwei samples on decreasing TG was the best and it was even better than dapagliflozin group. Only freeze-dried Guiwei lychee could significant decrease the TC content in blood among all lychee samples. In a word, Feizixiao lychees had the best antioxidant capacity and Guiwei lychees had the best hypoglycemic effect. Air drying was better drying method for lychee polysaccharides than freeze drying in this study.     

采前脱落酸处理对荔枝贮藏的保鲜作用

该试验以“井岗红糯”荔枝为材料,研究采前100 mg/L脱落酸（Abscisic acid,ABA）处理对常温贮藏荔枝采后品质的影响。结果表明：采前ABA处理明显延缓了果实褐变指数、病情指数和腐烂率的升高,保持较好的色度值（L*、a*和b*）,贮藏8 d ABA处理荔枝的褐变指数、病情指数、腐烂率分别为3.38、1.42和37.78%。贮藏8 d时,ABA处理荔枝果皮总酚含量、以及苯丙氨酸解氨酶（PAL）、多酚氧化酶（PPO）和过氧化物酶（POD）活性分别较对照高3.54%、1.38%、3.22%和18.39%;相对电导率（REC）、丙二醛（MDA）以及过氧化氢（H2O2）含量分别较对照低23.25%、11.85%和18.18%。此外,ABA处理荔枝果肉的可溶性固形物（TSS）、可滴定酸（TA）、维生素C（Vc）含量分别为17.70%、0.12%和30.14 mg/100 g,均高于对照。可见采前ABA处理不仅可以通过维持细胞膜完整性、减少酚类物质氧化、提高相关防御酶活性维持采后荔枝的外观品质,而且可以通过减缓TSS、TA和Vc含量的降低维持采后荔枝的营养品质。     

果香型干白荔枝酒酿造的质量控制及设备配置

要酿造好的果香型干白荔枝酒,首先要有好的荔枝原料,其次要有符合工艺要求的酿造设备,第三要有科学合理的工艺技术.原料和设备是硬件,工艺技术是软件.在硬件规定的前提下,产品质量的差异就只能取决于酿造荔枝酒的工艺技术和严格的质量控制.     

图解法优化荔枝果浆酶解澄清的工艺

为了制备荔枝澄清果汁,探讨不同的果胶酶用量(质量分数0.02％～0.06％,m/m),酶解时间(1～3h)和温度(35～55℃)等工艺参数对荔枝果汁的出汁率和澄清度的影响.结果表明果胶酶处理可以提高荔枝果汁的出汁率和澄清度.通过响应面试验设计分析和图解法优化途径,获得果胶酶制备荔枝澄清果汁的较优工艺条件,在酶用量0.045％～0.05％(m/m),温度46～50℃和时间2.0～2.5h时,荔枝果汁的出汁率和透光率的预测值分别为90.40％和91.10％.经实验验证,预测值与实验值相符.     

蜂蜡-水凝胶复合型荔枝材料的3D打印工艺

以荔枝干、食品胶(κ-卡拉胶和黄原胶)、蜂蜡和火龙果皮为原料,利用3D打印机、流变仪和扫描电镜探讨不同配比对复合型荔枝材料流变学性质与打印成型的影响,并对其微观结构进行了研究。当添加卡拉胶:黄原胶比例为1:1,蜂蜡添加量8.0 g,火龙果皮粉添加量2.0 g时,复合型荔枝油墨材料的稳定化时间为143.5 s,屈服应力为187.55 Pa,K值为1.72×105 Pa·sn,n值为0.22,制备的材料具备较好的剪切稀化性能、热可逆性和机械性能。打印出的产品精度较高,线条细腻,可叠放60层。材料的微观结构以κ-卡拉胶为骨架的网络状,黄原胶、荔枝果肉和果胶等依附在骨架上,蜂蜡以颗粒(直径10μm)附着在骨架的表层,在打印过程中与食品胶共同作用以影响材料的打印成型性。