Fabrication of olive leaf extract and hazelnut skin incorporated films to improve the quality of nuggets during refrigerated and deep freeze storage

ABSTRACT

1. Olive leaf extract (OLE) and hazelnut skin (HS), which are known to have good antioxidant activity, were added into chicken nuggets in different ways. In the first method, the nuggets were coated with sodium alginate-calcium chloride-based coatings containing OLE and HS. In the second method, OLE and HS were directly added into the nugget patties. Nuggets that did not contain any additive (C1) and the samples prepared with the coating solution that did not include any additives (C2) were assigned as controls.

2. Nuggets were stored at two different temperatures, either in a refrigerator (4°C) or in a deep freezer (?18°C) for 21 days and 90 days respectively. Moisture content (%), pH, antioxidant status (TBARS), colour and microbial count (total mesophilic and psychrophilic aerobic bacteria) analyses were carried out during storage.

3. At the end of refrigerator storage (day 21), TBARS values for samples in which OLE and HS were directly added were found to be lower than those with OLE and HS coatings (P < 0.05). Total number of mesophilic and psychrophilic bacteria were found to be the lowest in the treatment in which HS was directly incorporated into nugget patty (P < 0.05).

4. For frozen samples, application of a coating containing OLE and HS and direct addition of HS into patties were found to be effective in reducing lipid oxidation. No microbial growth was determined in most of the samples stored in the deep freezer.     

Cloning, characterization and expression of cDNA containing major histocompatibility complex class I, IIα and IIβ genes of Japanese flounder Paralichthys olivaceus

ABSTRACT:   The nucleotide sequences of Japanese flounder Paralichthys olivaceus , major histocompatibility complex (MHC) cDNA, classical MHC class Iα, non-classical MHC class Iβ, MHC class IIα and IIβ, were determined. The domain structures and antigen binding motifs of vertebrate MHC are conserved in the Japanese flounder MHC. A phylogenetic analysis supports the classification of these genes into class I and class II MHC. Classical MHC class Iα was ubiquitously expressed, whereas the non-classical MHC class Iβ was expressed mainly in lymphoid organs, gills, intestine and stomach. The MHC classes IIα and IIβ were also ubiquitously expressed.     

橄榄小孢拟盘多毛孢(Pestalotiopsis microspora)的生物学特性研究

橄榄小孢拟盘多毛孢(Pestalotiopsis microspora)是导致采后橄榄果实腐烂的主要病原菌,本文研究了pH、温度、光照、碳源、氮源等条件对橄榄小孢拟盘多毛孢菌落生长、产孢和分生孢子萌发的影响。结果表明,橄榄小孢拟盘多毛孢生长最适pH为6,最适温度24~26℃;产孢最适pH为7,最适温度24~26℃,光暗交替条件下产孢量最多;以D-果糖、甘露醇为碳源和以蛋白胨为氮源的培养基最有利于橄榄小孢拟盘多毛孢菌丝的生长,以葡萄糖、蔗糖为碳源和以蛋白胨为氮源的培养基最有利于该菌产孢;分生孢子萌发最适pH为6,最适温度26~28℃,全黑暗条件下孢子萌发率最高;该菌菌丝致死温度为54℃(30 min),分生孢子致死温度为56℃(20 min)。     

橄榄汁饮料的研制

研究了橄榄汁饮料的加工工艺。结果表明,采用质量分数为0.005%的果胶酶,酶解温度25℃,酶解时间60min,可获得理想的产率,橄榄汁的产率可提高为20%。通过调配(添加稳定剂、防腐剂、调节糖酸比),可生产出色、香、味俱佳的橄榄汁饮料。     

傅里叶变换红外光谱法在橄榄油掺假鉴别中的应用

采用傅里叶变换红外光谱仪对橄榄油、葵花籽油、花生油、玉米油、大豆油、菜籽油、棕榈油7种食用植物油的红外光谱信息进行分析。结果表明,橄榄油的红外吸收光谱在吸收峰的位置及吸光度上均与其他种类的植物油有区别,以3005~3009 cm^-1、1117~1121 cm^-1处的吸收峰作为种类区分。模拟掺假过程,向橄榄油中掺入其他6种不同比例的低价值植物油后,发现1097、3005 cm^-1处吸收峰的峰面积与掺假百分比呈线性关系。此外,对7种食用植物油180℃加热2 h后的红外光谱图进行分析,发现968、1097 cm^-1处的吸收峰变化趋势有差异,橄榄油呈上升趋势而其他种类的植物油则呈现下降趋势。掺假橄榄油加热后谱图分析发现3005 cm^-1处的峰面积有所降低,但与掺假百分比仍呈线性关系,掺入5%低价油,3400~3650 cm^-1区域呈明显增加趋势,据此可以鉴别掺假量低至5%的橄榄油,这为橄榄油的掺假鉴别提供了一种快速高效的方法。     

气相色谱法鉴别橄榄油掺伪的研究

应用气相色谱法分析测定橄榄油的脂肪酸组成,揭示橄榄油脂肪酸特征,并研究其掺入菜籽油、花生油、大豆油或精炼橄榄油时脂肪酸的变化规律,为橄榄油的掺伪鉴别提供参考依据。     

丽江市油橄榄引种栽培试验初报

在丽江市的大具乡建立油橄榄示范园,并于2006年开始先后引进国外14个油橄榄优良品种进行栽培试验。文中详细阐述了示范园建设中的整地、打塘、施肥、苗木定植以及建园后管理等各项技术措施。结果表明,大具乡的自然、气候条件非常适合油橄榄的栽培;油橄榄品种具有自交不亲和性,需要不同品种之间授粉;14个油橄榄品种在示范区的生长情况良好,大多数成活率都在80%以上,特别是2006年引进的ARBEQUINA SELC和KORONEIKI的生长挂果情况较为突出,2009年引进的鄂植8号、皮肖利和莱星生长、抗病性也非常突出,可重点选育这几个品种作为主栽品种进行推广种植。     

鲜食橄榄果实的适宜采收期及其品质评价参数的研究

以"檀香"橄榄果实为试材,研究7个采收期(从9月7日到12月7日按节气采果,分别为采收期Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ)对鲜食橄榄果实品质的影响及其品质评价参数。结果表明:随着采收期的延迟和果实成熟度的提高,采收期Ⅰ~采收期Ⅵ的橄榄果实表面色调角h°、果皮叶绿素含量、果肉可滴定酸和单宁含量下降,果皮类胡萝卜素含量、果肉可溶性固形物含量、固酸比值、可溶性总糖含量、还原糖含量和糖酸比值增加,果实食用品质提高;但采收期Ⅶ(过熟)的橄榄果实果肉可溶性固形物、可溶性总糖、还原糖含量和果实食用品质下降;因此认为,采收期显著影响鲜食橄榄果实品质,且以采收期Ⅵ(完熟,小雪节气采收)的橄榄果实鲜食品质最佳。同时发现,橄榄果实表面色调角h°,果皮叶绿素、类胡萝卜素含量,果肉可溶性固形物、可滴定酸、固酸比值、可溶性总糖、还原性糖、糖酸比值、单宁含量等品质指标可作为确定鲜食橄榄果实食用品质及采收期Ⅰ~采收期Ⅵ成熟度的参数,为量化衡量橄榄果实食用品质和成熟度提供方法。     

Genetic relationships and hybrid vigour in olive (Olea europaea L.) by microsatellites

The olive (Olea europaea) is one of the most important oleaginous crops of the Mediterranean basin. Increased demand for olive oil creates a need for new olive varieties to help meet the requirements of the global market. However, olive breeding has been handicapped by such varied challenges as a prolonged juvenile period, agrotechnical problems and insufficient genetic knowledge. The use of DNA markers has the potential to overcome these problems and increase the effectiveness of classical breeding programmes. In this study, co‐dominant polymorphic simple sequence repeats (SSRs) were used as markers to analyse the genetic relationships between several local and other ‘non‐native’ olive cultivars. Cluster analysis revealed four major groups among the 15 cultivars examined in this study. Table and oil cultivars were clustered in different groups. However, the clusters did not differentiate between cultivars of different geographical origins. In addition, we used the data gathered to analyse genetic relationships to evaluate the effects of heterosis in agricultural traits. Genetic distances between cultivars were determined based on the SSR genotype data and were used for evaluating the possible effects of heterosis in various F₁ populations. Interestingly, phenotypic data of F₁ progenies from crosses between different cultivars indicated the potential effects of heterosis as expressed in several traits. Genetic distance between parents was significantly correlated to F₁ performance for three traits: percentage of dry fruit weight, oil content and commercial oil production. Thus, crosses between olive cultivars exhibiting relatively extensive genetic distances one from the other are expected to result in better progeny performance in future Olea breeding programmes. Our study linked assessment of biodiversity of commercial olive cultivars with the application of this information in olive breeding programmes for selection of specific parents to generate superior new cultivars.     

Yield and olive oil characteristics of a low-density orchard (cv. Cordovil) subjected to different irrigation regimes

The impact of different irrigation scheduling regimes on the quantity and quality of olive oil from a low-density olive grove in southern Portugal was assessed during the irrigation seasons of 2006 and 2007. Olive trees were subjected to one of the following treatments: A—full irrigation; B—sustained deficit irrigation (SDI) with 60% of ETc water applied with irrigation; C—regulated deficit irrigation (RDI) with irrigation water applied at three critical phases: before flowering, at the beginning of pit hardening and before crop harvesting and D—rain-fed treatment. Olive oil yield was significantly higher than rain-fed conditions in 2006, an “on year” of significant rainfall during summer. No significant yield differences were observed in the following “off year”. Among the irrigated treatments, olive oil production of treatment B was 32.5% and 40.1% higher in 2006 and 2007, respectively than the fully irrigated treatment A, despite receiving 49% less irrigation water. Such strategy could allow for an efficient use of water in the region, of very limited available resources, and for modest but important oil yield increase. Nonetheless, on the “on year” of 2006 treatment C used 13.9% of the water applied to treatment B and produced only 23.9% less olive fruits which could also make it illegible as the next possible strategy to use for irrigating olive trees in the region, provided that water is secured latter in the summer, a period of vital importance for oil accumulation and very sensitive to water stress as the poor results of 2007 revealed. The different treatment water regimes did not impact on the chemical characteristics of olive oils that were within the set threshold limits. Similarly, the sensory characteristics of the olive oils as well as bitterness and pungency were negligible for all treatments allowing them to be assessed as of “superior quality”.Overall, irrigation treatments had no influence on the commercial value of produced oils, being all classified as “extra virgin”. Such funding may be of vital importance to farmers willing to further their irrigation area, save water and still retain the protected designation of origin (PDO) seal of quality for their oil.