Effect of different light transmittance paper bags on fruit quality and antioxidant capacity in loquat

BACKGROUND: Bagging has been widely used to improve the commercial value of fruit. The purpose of this study was to evaluate the effects of different light transmittance paper bags on the quality and antioxidant capacity of loquat fruit. Two loquat cultivars, Baiyu and Ninghaibai (Eriobotrya japonica Lindl.), were used for materials. One‐layered white paper bags (OWPB) with ～50% light transmittance and two‐layered paper bags with a black inner layer and a grey outer layer (TGDPB) with ～0% light transmittance were used as treatments and unbagged fruits were used as the control (CK) in this experiment. Fruit quality was determined by physicochemical characteristics, the quantity of sugar, total phenolic, flavonoid, carotenoid and vitamin C. The antioxidant capacities of the methanol extracted from the pulp were tested using three different assays. RESULTS: The results showed that bagging decreased the weight of fruit but promoted the appearance of loquat fruits. The total sugar content in the fruit bagged with OWPB was higher than in controls and in fruit bagged with TGDPB. The total phenolic and flavonoid contents were decreased by both bagging treatments, with the lowest occurring in the fruit bagged with TGDPB. Bagging also decreased the total antioxidant capacity of the fruit pulp, which was again lower in TGDPB‐treated fruits than in those bagged using OWPB. Correlation analysis showed a linear relationship between total antioxidant capacity and the content of total phenolic and flavonoid. CONCLUSION: The results showed that different light transmittance bags had different effects on fruit quality and antioxidant capacity. In particular, bags with low light transmittance (TGDPB) decreased the inner quality and total antioxidant capacity of loquat fruit. All results indicated that bagging with OWPB was more suitable for maintaining the quality of the loquat fruit than bagging with TGDPB. Copyright © 2010 Society of Chemical Industry     

香花枇杷与普通枇杷叶片提取物抑菌效果和抗氧化活性的比较研究

以香花枇杷和普通枇杷叶片提取物为实材,采用牛津杯抑菌实验、最小抑菌浓度(MIC)的测定、DPPH自由基清除率的测定对其不同萃取部分进行了抑菌效果和抗氧化活性的研究,以期比较这两个种类的抑菌和抗氧化活性。结果表明:对于供实菌,7个样品中抑菌效果最好的溶剂萃取部分是7#(上清液正丁醇部)、最差的是3#(沉淀乙酸乙酯部);与阳性对照山梨酸钾相比,香花枇杷和普通枇杷的不同萃取部位的最小抑菌浓度(MIC)更小,抑菌效果更好;极性较强的5#(沉淀萃取剩余部)、6#(上清液乙酸乙酯部)、7#(上清液正丁醇部萃取部)是抗氧化活性较强的部位。总体上,香花枇杷和普通枇杷相比,活性成分有较大的相似性,但具有更好的抑菌效果与抗氧化活性,可能存在潜在药用价值,有着较为广阔的应用前景。     

枇杷核总黄酮的提取及对羟基自由基清除作用的考察

以市售枇杷核为原料,用不同溶度乙醇浸提,研究其提取物对羟基自由基的清除效果。采用正交试验法对影响枇杷核总黄酮提取率的主要因素进行研究和分析,考察了乙醇浓度、回流温度、回流时间及料液比等四个因素对枇杷核总黄酮提取率的影响。并筛选出最佳工艺条件。枇杷核黄酮乙醇浸提最佳条件为：浸提时间2 h,固液比1∶20,浸提温度50℃。同时考察了在Fe2＋-水杨酸和H2O2发生羟基自由基的模拟体系中测定枇杷核提取液对.OH的清除效果。     

不同处理枇杷仁的脱毒效果比较研究

通过利用高效液相色谱测定苦杏仁甙的量,研究了干炒、水煮、粉碎对歙县枇杷主要栽培品种核仁中苦杏仁甙分解和氢氰酸存在的影响,得到以下结论:3种处理以水煮和粉碎有利于枇杷仁的苦杏仁甙的分解和氢氰酸的挥发,干炒后枇杷仁中仍有一定的毒性;枇杷仁中苦杏仁甙含量低,可以通过合理选择处理方法实现无毒利用。     

枇杷叶蛹虫草黄酒的研究与开发

以糯米为主料,枇杷叶,蛹虫草培养基作为辅料采用全液态化黄酒生产工艺酿造枇杷叶蛹虫草黄酒.利用单因素试验、正交试验分析了枇杷叶蛹虫草黄酒发酵过程中还原糖以及酒精含量的变化,得到最佳酿造工艺参数:枇杷叶,蛹虫草培养基与糯米的最佳配比为3∶1:16,酵母接种量为0.2％,发酵最佳时间为15d,酒精发酵时,前期32℃通风培养,后期28℃静置培养,此黄酒具有枇杷叶与蛹虫草的双重保健作用.     

D-最优混料设计优化富含番茄红素复合果蔬酒的主料配比

为丰富富含番茄红素产品的种类,采用番茄、芒果、南瓜和枇杷为原料,以感官评分及番茄红素含量为评价指标,利用模糊数学感官评价结合D-最优混料设计优化复合果蔬酒的主料配比,并对复合果蔬酒的理化指标进行分析。结果表明,复合果蔬酒的最优主料配比为番茄汁39.8%、芒果汁36.2%、南瓜汁16.0%和枇杷汁8.0%,采用复合果蔬酒的酿造工艺,可获得色泽橙红透明、果香与酒香浓郁、滋味醇和的复合果蔬酒,其感官评分与番茄红素含量分别为(94.81±0.47)分与(19.57±0.52)μg/mL,各项理化指标均符合QB/T 5476—2020《果酒通用技术》要求。     

植物乳杆菌R23在枇杷酒中生长及苹果酸乳酸发酵特性研究

目的:为植物乳杆菌R23菌剂的研发及其在果酒生物降酸上的应用提供理论依据.方法:以LH16为培养基,在不同温度、pH值条件下培养,测定生物量,确定最适生长条件;以枇杷酒为基酒,研究R23在酒中消长规律和苹果酸乳酸发酵(MLF)特性.结果与结论:植物乳杆菌R23的最适温度30℃、pH 6.0.植物乳杆菌在酒中的生长总体呈...     

枇杷果酒澄清与稳定性研究

以皂土、明胶 单宁、壳聚糖3种澄清剂对枇杷果酒进行澄清处理，并分析了澄清剂对枇杷果酒的品质、稳定性和色泽的影响。结果表明，0．5g/L的皂土可使枇杷果酒达到澄清稳定的效果，且对果酒的品质和色泽的影响不大；明胶 单宁法的澄清效果不明显；壳聚糖虽可使枇杷果酒澄清与稳定，但对果酒的品质和色泽影响较大。     

中草药复合涂膜保鲜剂保鲜枇杷的研究

本实验以刺槐豆胶与黄原胶复配胶为涂膜基质,分别加入中草药制剂丁香、大黄和艾叶及成膜助剂,配制成两种中草药复合涂膜保鲜剂,并以枇杷为实验材料,研究中草药复合涂膜保鲜剂对枇杷品质变化的影响。结果表明:经过涂膜的枇杷,腐烂程度较低,呼吸速率明显被抑制,VC、有机酸、可溶性固形糖等营养成分能较好地保存。其中配方B保鲜效果最显著。     

壳聚糖/纳米蒙脱土复合涂膜对枇杷保鲜的研究

采用壳聚糖和纳米蒙脱土作为复合涂膜剂,研究室温条件下对枇杷的保鲜效果。结果表明,壳聚糖/纳米蒙脱土复合涂膜剂能明显延缓水分流失,抑制硬度、VC含量、总糖含量和总酸含量的下降,有效延长枇杷保质期。