TEXTURE IMPROVEMENT OF FRESH-PACK DILL PICKLES BY ADDITION OF LACTOSE AND SUCROSE

The influence of small amounts of lactose or sucrose on texture of fresh-pack dill pickles was evaluated by Instron texture profile analysis (TPA). Pickles were prepared with 0, 2, 4 and 6% by weight of either lactose or sucrose in a commerical brine. After equilibration of pickles with brine (30, 64 and 77 days), TPA values were obtained for brittleness, hardness, elasticity and total work of compression. Analysis of variance for the linear regression showed significant relationships between TPA values and sugar concentration. A minimum of 6% sugar is considered necessary for meaningful texture improvement. Sensory evaluation showed that sweetness may be detectable at the 4% and 6% sucrose levels. The presence of lactose was not objectionable at these levels.     

Laboratory and Pilot Scale Recovery of Protein from Mechanically Separated Chicken Residue

Bone residue resulting from mechanical deboning of chicken backs and necks was subjected to alkali extraction followed by acid precipstation to recover food grade protein. A laboratory study of effects of varying die size in the grinding of the starting material, of extraction temperature, and of g-force during centrifugation on composition of process fractions was conducted. Grinding increased ash content, higher temperature reduced fat content, and increasing centrifugal force decreased ash content, of the final products. Effects of grinding, extraction temperature, and centrifugal type were also studied on a pilot scale. Final protein product yield was higher at a 22°C than at a 3–7°C extraction temperature, and less fat was incorporated using a basket centrifuge than with a horizontal decanter centrifuge.     

Model for Strength of Brittle Porous Materials

Many porous bodies form by the growth and joining of individual solid particles into a network-like structure. Assuming that the distribution of particles in the porous body is random, the relation between strength and porosity was derived and compared with commonly used empirical relations.     

EFFECT OF SOLAR DRYING ON THE COMPOSITION OF ESSENTIAL OIL OF SACHA CULANTRO (ERYNGIUM FOETIDUM L.) GROWN IN THE PERUVIAN AMAZON

Two solar drying methods (direct cabinet solar dryer and indirect cabinet solar dryer) were tested under tropical conditions for drying aerial parts of sacha culantro ( Eryngium foetidum L.) in Pucallpa City (Peruvian Amazon). The drying behavior was monitored during all experimental runs. Dried samples and fresh leaves were hydrodistilled and isolated oils were analyzed using gas chromatography with flame ionization detector and gas chromatography-mass spectrometry. ( E )-2-dodecenal was determined as the main constituent of the sacha culantro essential oil, averaging 61.8–62.2%, followed by n -dodecanal (10.9–15.5%), ( E )-2-tetradecenal (6.7–7.6%) and 1-tetradecene (3.6–5.7%). When comparing both solar drying methods, the indirect method was found as more suitable for drying E. foetidum since the dried product resembled the fresh herb more closely in its chemicalcomposition and had better appearance. However, a better drying efficiency of 10.3% was achieved when drying in the direct solar dryer compared with 5.8% for the indirect solar dryer.

PRACTICAL APPLICATIONS

Harvested leaves of sacha culantro are widely used as a condiment in a range of Peruvian, Latin American and Caribbean foods, including vegetable and meat dishes, canned food and sauces. There is lack of any postharvest processing of this herb although it may extend possibilities for use of the herb and facilitate the product export from local production areas and might be a good economic source for poor local farmers. This study shows solar drying as a reasonable preservation technique of sacha culantro leaves which may have a practical application in case of postharvest processing of the herb in the target region of Pucallpa City in Peruvian Amazon.     

Knockdown of apoptosis-inducing factor disrupts function of respiratory complex

Recent findings suggest that apoptotic protein apoptosis-inducing factor (AIF) may also play an important non-apoptotic function inside mitochondria. AIF was proposed to be an important component of respiratory chain complex I that is the major producer of superoxide radical. The possible role of AIF is still controversial. Superoxide production could be used as a valuable measure of complex I function, because the majority of superoxide is produced there. Therefore, we employed superoxide-specific mitochondrial fluorescence dye for detection of superoxide production. We studied an impact of AIF knockdown on function of mitochondrial complex I by analyzing superoxide production in selected cell lines. Our results show that tumoral telomerase-positive (TP) AIF knockdown cell lines display significant increase in superoxide production in comparison to control cells, while a non-tumoral cell line and tumoral telomerase-negative cell lines with alternative lengthening of telomeres (ALT) show a decrease in superoxide production. According to these results, we can conclude that AIF knockdown disrupts function of complex I and therefore increases the superoxide production in mitochondria. The distinct effect of AIF depletion in various cell lines could result from recently discovered activity of telomerase in mitochondria of TP cancer cells, but this hypothesis needs further investigation     

RADIOASSAY OF FOLACIN IN FOODSTUFFS

A commercial radioassay kit for folate (Radio-chemical Centre Amersham, England), produced for clinical analysis, has been tested for folacin assay in foodstuffs. The binding capacity of porcine binder was determined for different folates and compounds interfering with the microbiological assay. Recovery of standard addition of N⁵-methyltetrahydrofolate to the foodstuffs extracts estimated by radioassay varied from 96 to 105%.     

Thermal Denaturation of Hen Egg White Studied by Chromatographic and Immunochemical Techniques

The course of thermal denaturation of hen egg white at 70°C was studied in detail by fast gel chromatography on Superose 12 and by immunochemical techniques. The mechanism of thermal denaturation differed depending on the pH of the environment. The aggregation of protein at the beginning of heat treatment was typical at pH 5 while at pH 9 the breakdown to smaller fragments prevailed. The chromatographic method for the determination of thermally undamaged (native) ovalbumin correlated well with the immunochemical method.     

Oxygen Evolution During MnO-Mn3O4 Dissolution in a Borosilicate Melt

Foam evolution during dissolution of MnO-Mn₃O₄ pellets and powders in borosilicate glass was recorded photographically. The pellets were placed horizontally in transparent crucibles, covered with molten glass, and held at 1150°C. If the Mn₃O₄ content in pellets was more than 31 wt%, they developed foam after an initial foamless period. The length of the foamless period decreased and the duration of foaming increased as the Mn₃O₄ content increased. Batches prepared from MnO-Mn₃O₄ powders and frit, and soaked at 1150°C, foamed without an initial foamless period. The foam developed and collapsed before the set temperature was established within the melt and rose to a higher level than foam produced by pellets. Thermogravimetry of batches heated in 1 atm (∼10⁵ Pa) of O₂ shows oxidation at 400° to 600°C followed by mass loss due to volatilization and oxygen evolution.     

MEASUREMENT AND COMPUTATION OF PHYSICO-CHEMICAL PROPERTIES OF SUGAR SOLUTIONS

At the Department of Chemistry and Technology of Saccharides, Institute of Chemical Technology in Prague, we study technically important physical properties of sugar solutions. This paper deals with some results of measurement and correlation of boiling point elevation and density.

The present system of tables or nomograms of physical properties of sugar solutions is not satisfactory for automated data processing. In a critical analysis of the existing material it appears that physico-chemical data for sugar solutions were often compiled over ranges of variables which were interesting for laboratory control and not for engineering computations. That all calls for purposeful completion of data in the regions where they are lacking. Additionally, it calls for revision of tabulated values from the literature and for transformation of the tabulated data to functional relationships in order to make computation equations both precise and simple