Investigation of technological approaches for reduction of methanol formation in plum wines

Methanol is natural ingredient of alcoholic beverages and soft drinks; however, the products of its metabolic transformations (formaldehyde and formic acid) are toxic to humans. The aim of this research was to assess the application of different physico‐chemical treatments of pomace in order to find the most efficient method for reducing the methanol during fermentation with the least effect on the sensory properties of the wine. The following procedures were studied: addition of tannins in pomace, addition of phenolic acids, addition of d ‐galacturonic and pectic acid, use of bentonite and zeolite, heat treatment of pomace, thermosonication and treatment of pomace with microwaves. Fruit wine used in this study was produced from plums (Prunus domestica L.). Applied treatments showed variable efficiency in reduction of methanol formation in plum wine. It may be noted that the procedures that involved some form of thermal treatment were characterized by a significant decrease in the production of methanol (up to 60–70%) but mostly tended to have a negative impact on the sensory properties of the produced wines. However, exposure of pomace to microwaves for a short time, owing to the contribution of mechanisms of non‐thermal nature (kinetic and chemical), allowed for a significant reduction in methanol formation with a negligible impact on the sensory properties. The decrease in methanol formation during fermentation using tannins, pectic acid, bentonite and zeolite was poor, with only a reduction of up to 15%. Obtained results are significant to the fruit wine and spirit industry, considering the common problem related to an increased content of methanol in these beverages. Copyright © 2016 The Institute of Brewing & Distilling     

Changes in chemical composition of the kew cultivar of pineapple fruit during development

The chemical composition of the Kew cultivar of Indian pineapple (Ananas cosmosus L.) was studied after 65 days (pre-mature), 100 days (early mature), and 150 days (late-mature) from flowering. The fruit was analysed for sugars, amino acids and minerals. Total soluble carbohydrates increased from 6.02 to 9.24%, and protein content decreased from 0.69 to 0.21%, during the fruit-development process. The vitamin C content decreased from 20.4 to 11.1 mg 100 g^?1 edible fruit during development. Fructose, glucose and sucrose together constituted approximately 5.0% (pre-mature), 2.4% (early mature), and 1.2% (late-mature) of fresh weight. The contents of iron, boron and zinc increased during development. The major minerals in the mature fruit were potassium (31.33 mg 100 g^?1), phosphorus (3.13 mg 100 g^?1), calcium (3.92 mg 100 g^?1), sodium (2.63 mg 100 g^?1), iron (3.22 mg 100 g^?1), zinc (0.55 mg 100 g^?l), and copper (0.06 mg 100 g^?1) of fresh sample. The content of most amino acids decreased during development; only aspartic acid showed a considerable increase in the late-mature fruit.     

臭氧果蔬保鲜销售包装的实验研究

介绍了臭氧果蔬保鲜技术的作用机理及其特点;在分析果蔬保鲜包装技术要求的基础上,应用臭氧技术结合包装技术方法,在常温下对西红柿、豆角进行了臭氧保鲜实验研究,对腐烂率、减重率、硬度、可溶性固形物含量、还原糖含量、总酸、VC含量、叶绿素含量等指标进行了测试,结果表明:以上果蔬的保鲜期至少延长2周以上,对现代销售中的果蔬保鲜包装具有指导意义.     

Singlet Oxygen Quenching Activities of Various Fruit and Vegetable Juices and Protective Effects of Apple and Pear Juices against Hematolysis and Protein Oxidation Induced by Methylene Blue Photosensitization

ABSTRACT:  Effects of various fruit and vegetable juices on rubrene oxidation induced by a chemical source of singlet oxygen in a microemulsion system have been studied. The singlet oxygen quenching activities of fruit and vegetable juices were greatly different with different juices. The apple and pear juices exhibited the highest antioxidative activity among the tested juices in singlet oxygen–induced rubrene oxidation, showing 56.69% and 59.34% inhibition, respectively. The grape, kumquat, red cabbage, and spinach juices also showed relatively strong antioxidative activity against singlet oxygen–induced rubrene oxidation. Lemon juice showed the least activity, resulting in 0.63% inhibition of rubrene oxidation. The singlet oxygen quenching activities of 1 mL of apple and pear juices were equivalent to 33.97 and 34.64 mg ascorbate, respectively. Singlet oxygen quenching activities of juices had very low correlation with both ABTS radical scavenging activity ( R ²= 0.11) and total phenolic contents ( R ² < 0.1). However, a high correlation ( R ²= 0.66) was found between the ABTS radical scavenging activities and total phenolic contents of juices. The apple and pear juices also significantly inhibited both erythrocyte lysis and protein oxidation induced by fluorescence light illumination in the presence of methylene blue. Electron spin resonance (ESR) spectroscopy data showed that the protective activities of these juices against biological damages induced by photodynamic ways were, to at least some extent, due to their singlet oxygen quenching abilities. This represents first report on the singlet oxygen quenching activities of the apple and pear juices, and their protective activities against photodynamically induced biological damages.     

Protective effect of the fruits of Terminalia arjuna against cadmium-induced oxidant stress and hepatic cell injury via MAPK activation and mitochondria dependent pathway

Cadmium (Cd), a highly toxic environmental pollutant, induces hepatic disorders. The present study has been undertaken to investigate the protective role of the fruit extract of Terminalia arjuna (AE) against Cd-induced oxidative liver impairment using a murine model. Cadmium reduced hepatocytes viability, activated MAPKs, disturbed Bcl-2 family protein balance, increased reactive oxygen species (ROS) production and induced apoptotic cell death by mitochondria dependent caspases-3 activation. AE treatment, however, suppressed all the apoptotic actions of cadmium. Similarly, mice treated with cadmium altered a number biomarkers related to hepatic oxidative stress and other apoptotic indices. Oral administration of AE both pre and post prevented all the Cd-induced hepatic damages.     

维药刺山柑果实挥发油和脂肪酸成分的GC-MS研究

目的:为了研究刺山柑果实挥发油和脂肪酸的成分。方法:使用气相色谱与质谱联用对刺山柑果实的挥发油和脂肪酸进行分析。结果:检测出46种挥发油,异硫氰酸酯类化合物约占总含量的83．14%;9种脂肪酸,必需脂肪酸含量为63．06%,出油率为15．6%。结论:GC-MS分析结果较好。     

酒浸泡冬枣果脯的开发研究

以酒泡冬枣为主料,在传统枣类果脯加工工艺基础上,研究糖煮工艺过程中各影响因素对冬枣果脯水分含量、糖分含量及感官质量的影响。通过正交试验得到的冬枣果脯加工的最佳工艺条件为:糖煮时间(75～90)min、干燥条件(65℃、14h)、白糖添加量(57.98%),最佳柠檬酸溶液浓度(0.19%)。在该工艺条件下,生产出的果脯糖含量65%以上,水分含量20%以下,风味优良。     

顶空进样-毛细管柱气相色谱法检测果啤风味物质

利用顶空进样、小口径毛细管柱气相色谱法测定果啤风味物质的含量。该方法采用氢火焰离子化检测器，并用面积归一化法进行计算。实验结果表明，分离色度高，色谱峰对称，平均回收率在98％以上，相对标准偏差在1％之内；该方法重现性好、简单、方便、快速、准确，能满足对分析检测的需要。