Significance of furosine as heat-induced marker in cookies

The effects of recipe formulation in terms of leavening agents (ammonium and sodium bicarbonates), sugars (sucrose and glucose), initial moisture content, and baking conditions (temperature and time) on furosine formation in cookies were studied. The cookies were baked at different temperatures for different times to monitor the progress of the early stage of the Maillard reaction. Change in furosine levels as an indicator of the Amadori products showed a typical kinetic behavior with a rapid increase to an apparent maximum followed by exponential decrease during baking. Initial water activity of cookie dough had no remarkable effect on the apparent maximum, but lowering the water activity decreased the time required to attain it. In addition, levels of furosine in the final product are highly correlated to the initial water content of dough at the same baking conditions. The levels of furosine attained were significantly lower in cookies composed of sucrose than in cookies composed of glucose. Early stage of the MR is rapidly overcome during baking as the Amadori product degraded in the advanced stage. Among the leavening agents, ammonium bicarbonate was the most effective for the progress of the Maillard reaction in cookies during baking.     

Study on nonenzymatic browning in cookies,crackers and breakfast cereals by maltulose and furosine determination

Nonenzymatic browning development has been investigated in commercial cookies, crackers and breakfast cereals by determination of maltulose and furosine. In addition, maltose, lactose, lactulose, fructose, glucose and 2-furoylmethyl-GABA were also determined in the samples studied. Maltulose and furosine were present in all samples of cookies, crackers and breakfast cereals. Differences found among samples may be attributed to variations in composition and processing conditions. The maltose/maltulose ratio showed a wide range in the samples studied and could probably be attributed to differences in heating intensity during processing. Thus, maltose/maltulose ratio might serve as indicator of the heat load during manufacture. Furosine and 2-furoylmethyl-GABA may arise from Maillard reactions in some of the ingredients before manufacture of the cereal products: this appears to be a major drawback for the use of these compounds as suitable indicators to differentiate between commercial cereal products. However, in the cereal industry, where exact ingredient composition is known, measurement of the maltulose and furosine formed might be used as indicators to monitor processing conditions during the manufacture of cereal products.     

Properties of sugar-snap cookies as influenced by lauric-based shortenings

The objective of this work was to assess the effect of different lauric-based shortenings with varying solid fat content (SFC) on sugar-snap cookie dough properties and cookie quality. Shortenings were produced by blending high oleic sunflower oil, palm kernel oil and palm stearin in different ratios, obtaining shortenings with different SFCs. It was observed that the SFC of the shortening largely influences the rheological properties of the cookie dough. At small deformations, fat crystals add elasticity to the dough; while at large deformations, fat-structure is disrupted, and it does not contribute to dough hardness. Fats with intermediate SFCs decrease dough resistance due to an enhanced shortening ability. Nevertheless, this effect is only obtained when shortening is homogeneously distributed in the dough. The SFC of the shortening influences dough and cookie structure by preventing gluten polymerization which was observed by a decrease in cookie break strength. A prerequisite for this effect is that shortening is finely dispersed in the dough. Good quality cookies were obtained using lauric-based shortenings, and best results were obtained with SFC between 20 and 25%. Higher SFC (around 45–50%) led to the production of unacceptable sugar-snap cookies.     

Physicochemical characteristics as the markers in predicting the self-life of gluten-free cookies

The objective of this study was to investigate the effect of different storage conditions on physicochemical stability assessment of gluten-free rice-buckwheat cookies. Second order polynomial (SOP) models were developed to explore the effects of storage time (0–6 months), at ambient (23 ± 1 °C) and elevated (40 ± 1 °C) temperature, packaging condition (packed and unpacked samples), and cookie surface position on the level of water activity (a_w), hydroxymethylfurfural content, peak force, and colour parameters (L*, a*, b*, h*, C*, ΔE*). The chemical characteristics of cookies were influenced by temperature, while the colour properties were mostly influenced by the position of the sample surface. The firmness was affected upon the synergy effect of temperature and packaging condition. The performance of the developed SOP models was to investigate the effect of storage conditions on the observed parameters, which showed a good fit to the experimental (r² > 0.8). The obtained results demonstrated that the developed empirical models gave an appropriate fit to experimental data and predicted the physicochemical properties at a satisfactory level, and that they could be successfully implemented to cookie stability assessment.     

Physico-chemical properties of low-fat cookies containing wheat and oat bran gels as fat replacers

Wheat and oat bran-based fat replacers in the form of gels were used for partial replacement of fat (30–50%) in a cookie formulation. Dough rheological properties, physical (cookie dimension, weight loss, moisture content and water activity), textural (hardness and fracturability), colour and sensory parameters were evaluated to characterize full-fat and fat-reduced cookies. Based on the obtained results it was concluded that the fat reduction in cookie formulation at the level of 30% maintained sensory properties of the full-fat cookies. Therefore, this level of fat replacement was chosen for further analysis: 30% WBG (wheat bran gel-containing cookies) and 30% OBG (oat bran gel-containing cookies) were examined in terms of nutritional and functional properties. It was revealed that fat replacement using bran gels at the level of 30% resulted in the fat-reduced added-value cookies in terms of dietary fibre, minerals and phenolics. 30% WBG cookies possessed higher dietary fibre, mineral and phenolic content in comparison to 30% OBG and the full-fat cookies.     

Characterization of Chilean hazel nut sweet cookies

A series of studies were carried out to test the effect of the incorporation of Chilean hazel nut flour in sweet cookies at the levels of 0%, 5%, 10%, 15% and 20%. The proximate chemical analysis of the different flour mixtures showed a regular increase from 7.2 to 12.2%, 14.5% to 18.8% and 1% to 2.2%, respectively, decreasing at the same time with the percentages of water and carbohydrates. Chemical amino acid scores of leucine and threonine in wheat flour improved with the incorporation of Chilean hazel nut flour. The farinographic evaluation made to the different blends showed several changes occurred with the incorporation of Chilean hazel nut flour to wheat flour. These included increase in water absorption, decrease in dough developing time and weakening of the dough. Sensory characteristics such as appearance, texture, flavor and also acceptability improved with the incorporation of Chilean hazel nut flour into the cookie formulaes.     

Effects of extrusion cooking conditions and chemical leavening agents on lysine loss as determined by furosine content in corn based extrudates

The aim of this study was to investigate the effects of different variables on lysine loss as determined by furosine content in corn-based extrudates. Three formulations were prepared to study the effects of different chemical leavening agents, processing conditions (feed moisture content: 22, 24 or 26%; exit die temperature: 110 or 150 °C), and extrusion cooking methods (with/without CO₂ injection) on furosine formation. Furosine levels of extrudates from both extrusion methods decreased around 20% when feed moisture content was increased from 22% to 26%. Amadori compounds (precursor of furosine) are formed in the early stages of the Maillard reaction, and later they are converted to further products. Consequently, furosine contents of extrudates significantly decreased as exit die temperature increased from 110 to 150 °C. Furosine contents of extrudates produced with sodium- and ammonium-bicarbonate at 150 °C exit die temperature significantly decreased, while the ones produced at 110 °C significantly increased. This may be due to accelerated formation of fructosyllysine at higher pH values followed by early degradation at 150 °C. The CO₂ injection method did not have a significantly different effect on furosine content of extrudates than that produced by the conventional extrusion method, but had a positive effect on the physical properties of extrudates.     

Production of low-fat cookies and their nutritional and metabolic effects in rats

Two weaning formulations were designed using computer software and then processed on a pilot plant scale by three different schemes involving extrusion cooking and traditional food processes such as soaking, decorticating and toasting to yield a total of six precooked experimental mixtures. The ingredients incorporated into these formulations were maize, cowpeas, peanuts, soybeans and soybean oil. Proximate composition indicated protein and lipid contents of 17.5-20.0 g/100 g and 7.8-9.1 g/100 g, respectively. Mineral analyses performed on samples indicated that the concentrations of copper, magnesium and zinc were comparable to those predicted whereas the concentrations of calcium and iron were lower than had been expected. Thiamin, riboflavin and niacin content ranged between 50-80% of the values predicted by the software. The differences could be due to varietal differences inherent in the nutrient profile of the raw materials or a result of processing these mixtures. However, a 100 g portion of all the supplements met at least one-third of the daily nutrient requirement of the 0.5-0.9 year old infant for selected micronutrients.     

Processing of commercial peanut cake into food-grade meal and its utilization in preparation of cookies

The commercial cake produced during expeller pressing of peanuts was extracted with n-hexane, and 80% ethanol followed by sieving through 80 mesh, to remove residual oil, pigments, bitter taste and fibrous material. The processed meal exhibited comparable composition with defatted peanut flour prepared in the laboratory by solvent extraction of full-fat peanut meal. However, the processed cake meal exhibited low methionine content and in vitro protein digestibility as compared with defatted peanut flour. The processed cake meal can be blended with wheat flour to the extent of 10% (w/w) to prepare acceptable cookies with improved protein and mineral contents.     

Comparison of different rice flour- and wheat flour-based butter cookies for acrylamide formation

Acrylamide (AcA) contents of different rice flour- and wheat flour-based butter cookies baked at 130 °C for 20, 55, or 90 min were investigated. AcA contents of different flour-based cookies increased with baking time. Color parameters in terms of CIE L*, b*, C*, and ΔE values showed significant opposite correlation to the AcA formation in each of the raw flour cookie. The cookies based on white rice flour had the lowest AcA contents ranging from not detectable (ND) to 204 μg/kg, followed by cookies based on brown rice flour (ND to 450 μg/kg), white wheat flour (155 μg/kg to 661 μg/kg), and whole wheat flour (306 μg/kg to 982 μg/kg). Considerably lower AcA levels were found in the rice flour-based cookies than in the wheat flour-based cookies, as well as in the milled flour-based cookies than in the whole-grain cookies. Although the flour source was considered to play a primary role in determining the AcA content, AcA content was apparently not dependent on the quantities of reducing sugars and free asparagine in the starting raw flour and cookies during baking. In summary, given its reducing potential for AcA formation, rice flour could be used in the production of cookies safe from heat-induced contaminants.     

Studies on the development of nutritious cookies utilizing sunflower kernels and wheat germ

Wheat germ and sunflower kernels were substituted at a level of 0, 5, 10, 15, 20, 25 and 30 percent of wheat flour for the preparation of cookies. The crude protein, ash and crude fiber contents increased with the addition of sunflower kernels. Similarly, with the addition of wheat germ, protein, ash and crude fibre contents increased significantly. The cookies containing 30% wheat germ and 20 percent sunflower kernels were found to be superior in overall acceptability.     

Allele and isozyme patterns of UDP-glucose pyrophosphorylase as a marker for cold-sweetening resistance in potatoes

Uridine-5-’diphosphoglucose pyrophosphorylase (UTP α-D-glucose-l-phosphate uridylyltransferase, E.C. 2.7.7.9) (UGPase) was cloned from 16 potato cultivars(Solanum tuberosum L.) that differed in their ability to accumulate reducing sugars in cold storage (3 C) using RT-PCR. Two UGPase-alleles designatedas UgpA (minus a BamHl site) and UgpB (containing oneBamHl site), were present in most cultivars. Cultivars that were cold-resistant (CR) to sweetening demonstrated an UgpA:UgpB ratio favoring the UgpA allele (4:0 or 3:1), while cultivars that were cold-sensitive (CS) exhibited a predominance for the UgpB allele (1:3 or 0:4). Following cold-storage at 3 C for two months, the CR and CS clones accumulated 10.3 ± 2.1 and 31.2 ± 2.2 umol glucose/g FW, respectively. The glucose content and chip color between the CR and CS clones were significantly different at the 99% level of confidence. Staining for UGPase activity in nondenaturing polyacrylamide gels of proteins extracted from CS potatoes revealed up to three acidic isozymes of UGPase (i.e., UGP1, UGP2, UGP3) with UGP3 being the most abundant. Activity staining using CR cultivars demonstrated two additional isozymes of UGPase with greater electrophoretic mobility (more basic in charge) which were designated UGP4 and UGP5. The potential for using UGPase allelic ratios and/or UGPase isozymic patterns as a selective tool to screen segregating progeny in a potato breeding program for cold-sweetening-resistant germplasm is discussed.     

pmi基因作为一种新型的安全选择标记基因的研究进展

pm i基因作为一种新型的安全选择标记基因在植物转基因研究中有着广阔的应用前景。本文从作用机理、基因来源、安全性评价、实际应用、发展前景和不足等方面对其进行了概述。     

大豆EST-SSR标记开发及与Genomic-SSR的比较研究*

本研究对458220条大豆EST序列进行SSR搜索,共检测出EST-SSR序列39989条, 经拼接得到无冗余EST-SSR序列8190条,包括357种重复基元。其中二、三核苷酸重复基元类型居多,分别占无冗余EST总数的11.13%和16%,统计得到二核苷酸重复类型12种,三核苷酸重复类型60种。以含有简单重复序列的无冗余EST序列设计200对引物,其中148对引物有清晰且单一条带扩增产物,以30份大豆品种资源进行引物筛选,获得多态性引物31对。以21份大豆不同基因型的基因组DNA为模板选取30对显示多态性的大豆EST-SSR引物和30对大豆基因组SSR引物进行扩增,带型统计结果显示：大豆EST-SSR与基因组SSR在供试基因型间多态性指数均值分别为0.55 和0.44,二者揭示的多态性水平差异不大。从而说明利用生物信息学方法基于大豆EST开发SSR标记是切实可行的,大豆EST-SSR可以用于大豆遗传多样性分析,是大豆DNA分子标记体系的一个重要补充。     

Phosphomannose isomerase,pmi, as a selectable marker gene for durum wheat transformation

Transgene technology provides a powerful tool for developing traits that are otherwise difficult to achieve through conventional methods. The development of transgenic plants requires the use of selectable marker genes, as the efficiency of plant transformation is less than optimal for many important species, especially for monocots such as durum wheat (Triticum turgidum var. durum). Many concerns have been expressed about the persistence of currently used marker genes in plants used for field cultivation. To sustain further progress in this area, alternative efficient selection methods are desirable. A recent development is the use of selective genes that give transformed cells a metabolic advantage (positive selection) compared to untransformed cells, which are slowly starved with a concomitant reduction in growth and viability. This selection strategy is in contrast to traditional negative selections during which the transgenic cells are able to survive on a selective medium whereas the non-transgenic cells are actively killed by the selective agent. We compared the ‘selection efficiency’ of a commonly used negative selection method that employs the Streptomyces hygroscopicus bar gene to confer resistance to the herbicide bialaphos, to a positive selection employing the Escherichia coli phosphomannose isomerase (pmi) gene as the selectable gene and mannose as the selective agent. Calli derived from immature embryos of the durum wheat cultivar Svevo were bombarded separately with bar and pmi genes using a biolistic system. The integration and expression of the two genes in the T₀ generation were confirmed by PCR analysis with specific primers for each gene and the chlorophenol red assay, respectively. The selection efficiency, calculated as the number of expressing plants divided by the number of total regenerants, was higher when pmi was used as the selectable marker gene (90.1%) than when bar was used (26.4%). Thus, an efficient selection method for durum wheat transformation was established that obviates the use of herbicide résistance genes.     

The use of carbohydrate antigen (CA) 15-3 as a tumor marker in detecting breast cancer

This study was carried out to determine the sensitivity and specificity of serum CA 15-3 as a marker in detecting and monitoring treatment in, breast cancer patients. One hundred and ten patients comprising 35 known breast cancer patients, 75 suspected cases and 20 controls entered the study. Blood samples were taken before and after treatment from the 35 known cases as well as the 75 suspected cases from which biopsy specimens were also taken. Serum CA 15-3 was measured by BioCheck CA 15-3 Enzyme Immunoassay. There was a significant difference between the concentration of serum CA 15-3 of the 35 known breast cancer patients before and after treatment (p < 0.05). Out of the 75 suspected cases, 46 had breast cancer and 29 had benign breast disease (histologically proven). There was a strong positive correlation between the level of serum CA 15-3 and the histopathology results of the biopsies (r = 0.518). The mean serum CA 15-3 concentration of the 46 patients (80.6 +/- 70.2 U mL(-1)) was significantly higher (p < 0.05) than that of the 29 patients with benign breast disease (12.0 +/- 9.0). The sensitivity and specificity of the serum CA 15-3 in detecting breast cancer was 76.1 and 100%, respectively at a cut-off of 35 U mL(-1). Serum CA 15-3 was found to have a value in the early detection and monitoring of treatment of breast cancer in Ghana.     

Enrichment of cookies with glutathione by inactive yeast cells (Saccharomyces cerevisiae): Physicochemical and functional properties

Cookie is one of the favorite cereal products which could be formulated by using various ingredients for enrichment. The aim of this study was to determine the effects of the inactivate yeast cells addition to cookie formulation in terms of glutathione (GSH) content, antioxidant activities, physicochemical and sensorial properties. Also, the cookies were produced with GSH (pure, 98%) addition to compare the effects of inactive yeast GSH with pure GSH on revealed properties. According to results, The GSH contents and the antioxidant activities increased in dough and cookie samples with inactive yeast addition compared to control and pure GSH added dough and cookie samples. The increases in GSH contents and antioxidant activities were observed after baking in all samples. The pure GSH addition increased the moisture content, spread ratio and L* value while decreased the hardness and b* values of the cookies. The contrary results were obtained by inactive yeast addition in terms of the physicochemical properties where the protein content of the cookies increased with inactive yeast addition by approximately 25%. The loss of GSH content decreased while the antioxidant activities and nutritional value increased in cookies by inactivate yeast addition.     

Formulation and sensory evaluation of Prosopis alba (Algarrobo) pulp cookies with increased iron and calcium dialyzabilities

Prosopis alba (algarrobo) is an important indigenous specie, which fruits are used as food and feed since ancient times. Cookies containing algarrobo pulp (AP) with increased iron and calcium availabilities were formulated and sensory evaluated. AP is preferred as food ingredient because of its high sugar content and pleasant flavour. Formulated cookies mean proximal composition was 8.9 g/100 g protein, 7.2 g/100 g dietary fiber, 25 g/100 g total sugar, and 18.5 g/100 g crude fat with iron and calcium contents 30 ppm and 340 ppm, respectively. Ascorbic (AA) and citric (CA) acids at different mM acid: mM Fe were added in order to increase mineral availabilities being evaluated by an in vitro method. Those ratios were 5:1 and 10:1 for AA:Fe whereas for CA:Fe were 50:1 and 100:1 and combinations of them. After chosen the best AA:Fe and CA:Fe ratios (5:1 and 50:1, respectively), sensory evaluation with trained sensory panel and a consumer acceptability test with one hundred and seventy untrained judges were carried out. Acceptability test showed that 77.65% of the people (< 25 years old 41.76%, 25-50 years old 20.00% and > 50 years old 15.89%) tasting final formulated cookies indicated that they "like very much" or "moderately like" and there were not consumers rejecting them.     

Volatile organic compounds as a diagnostic marker of late blight infected potato plants: A pilot study

Volatiles from potato plants infected with Phytophthora infestans (Mont.) de Bary were monitored by in situ headspace sampling. The sampling was done in four periods i.e. 28–42, 52–66, 76–90, and 100–114 h after inoculation (HAI). The headspace samples were analyzed by a gas chromatography–flame ionization detector (GC–FID) to assess the differences in volatile fingerprints between the infected-plant group and control groups, i.e. non-inoculated-plant and empty-vessel groups. The samples were subsequently analyzed by gas chromatography–mass spectrometry to identify specific peaks observed by GC–FID. Spore germination, infection, symptom development and sporulation were also monitored to ascertain the disease developmental stage when marker volatiles were first generated. The first symptoms of infection were visible after two days. Three marker volatiles i.e. (E)-2-hexenal, 5-ethyl-2(5H)-furanone and benzene-ethanol were found in the third and fourth trapping periods (3–4 days after inoculation) when sporangiophores were already formed. The volatile metabolites from blighted plants could be applied for sensor development to detect the occurrence of the disease in the field as well as for investigation of volatile production in relation to plant responses to infection.     

Use of stomatal index as a marker to screen backcross populations of two wild potato species segregating for freezing tolerance

The purpose of this study was to investigate differences in stomatal index among backcross progeny ofSolanum commersonii (freezing tolerant) andSolanum cardiophyllum (freezing sensitive) to assess the feasibility of using this trait as a marker for screeningSolanum populations for freezing tolerance. Measurements were taken on three terminal fully-expanded leaflets per genotype by completing microscopic examination of epidermal impressions made in partially dissolved cellophane tape. Freezing tolerance was estimated in parallel studies on the same plant material. Values of SI were significantly greater (Fisher T-test, 0.05) for theS. cmm. group (parent + backcross progeny) compared with theS. cph. group. Stomatal index of the F₁ was significantly greater than SI ofS. cph. parents and similar toS. cmm. parents. Values of SI for both backcross progenies were greater than parental values. Non-acclimated relative freezing tolerance values were in the following order:S. cmm. parents >S. cmm. backcrosses > F₁ >S. cph. back-crosses >S. cph. parents. Stomatal index values followed a similar pattern with the exceptionS. cmm. backcross >S. cmm. parents. These data suggest: a) increased SI is inherited as a dominant trait, b) SI may be a useful screening marker in breeding programs interested in improving freezing tolerance.