SOLAR TUNNEL DRYING OF TURMERIC (CURCUMA LONGA LINN. SYN. C. DOMESTICA VAL.) FOR QUALITY IMPROVEMENT

Turmeric is one of the most ancient medicinal spices of the world. As its homeland, India acts as the largest producer, exporter and consumer of turmeric. The value of turmeric is due to its color and flavor, which is being given by curcumin, volatile oil and oleoresin. The end quality of turmeric is very much dependent on its post-harvest methods. Traditionally, open sun drying is the chief method adopted for processing. In the present investigation, freshly harvested turmeric rhizomes were collected from 30 stations and drying experiments were conducted by adopting three methods: (1) solar tunnel drying; (2) conventional drying; and (3) commercial drying. Various pre-drying and post-drying treatments were conducted. The results proved that conventional processing could maintain the intrinsic quality up to a certain level, but extrinsic quality could not be achieved. Solar tunnel drying method is an effective alternative to traditional open sun drying, where retention of curcumin, volatile oil and oleoresin was high, with less drying time. The study also disclosed the importance of pre-drying and post-drying treatments and hygienic practices to be adopted during processing.

PRACTICAL APPLICATIONS

Solar tunnel dryer can be used to process most of the spices, vegetables, fruits and other perishable crops with maximum retention of intrinsic quality and for better shelf life. Substantial reduction of drying time and physical quality improvement with regard to international quality standards are the other advantages.     

PURIFICATION OF WET PROCESS PHOSPHORIC ACID BY SOLVENT EXTRACTION WITH ISOAMYL ALCOHOL. PART II. STUDY OF THE IMPURITIES DISTRIBUTION.

ABSTRACT

In the present paper, information about the purifying of wet process phosphoric acid (WPA) by Isoamyl Alcohol (iA) is reported. Distribution coefficients of impurities such’ as Fe, Al, Mg, SO⁼ ₄and F, as well as the distribution of Phosphoric Acid (PA) and Isoamyl alcohol were obtained.

Furthermore the variation of the relative distribution coefficients and selectivities of the different impurities was studied as a function of the PA weight percent (wt%) in the organic phase. Removal of the impurities Fe, Al, Mg and SO⁼ ₄is favoured when decreasing PA wt% in the organic phase. Selectivity of F shows different behaviour, passing through a maximum when plotted against PA wt% in the organic phase     

REMOVAL OF SULFAMETHAZINE FROM ARTIFICIALLY CONTAMINATED MILK BY ULTRAFILTRATION

The effect of discontinuous diafiltration (DD) on removal of sulfamethazine (SMZ) from raw whole and homogenized milk was studied. Milk was artificially contaminated with concentrations of SMZ varying from 20 to 90 μg/L. A hollow-fiber membrane with a molecular weight cut-off of 10,000 daltons was used for all experimental runs at 55C. The removal pattern of SMZ was influenced (P<0.05) by both the initial concentration and the homogenization process. Homogenization increased the removal of SMZ from milk. The DD process resulted in concentrates with residual levels of SMZ <10 μg/L (FDA action level). SMZ was not detected in reconstituted retentates resulting from milk originally up to 30 μg/L.     

Methods to calibrate and scale axial distances in confocal microscopy as a function of refractive index

Accurate distance measurement in 3D confocal microscopy is important for quantitative analysis, volume visualization and image restoration. However, axial distances can be distorted by both the point spread function (PSF) and by a refractive‐index mismatch between the sample and immersion liquid, which are difficult to separate. Additionally, accurate calibration of the axial distances in confocal microscopy remains cumbersome, although several high‐end methods exist. In this paper we present two methods to calibrate axial distances in 3D confocal microscopy that are both accurate and easily implemented. With these methods, we measured axial scaling factors as a function of refractive‐index mismatch for high‐aperture confocal microscopy imaging. We found that our scaling factors are almost completely linearly dependent on refractive index and that they were in good agreement with theoretical predictions that take the full vectorial properties of light into account. There was however a strong deviation with the theoretical predictions using (high‐angle) geometrical optics, which predict much lower scaling factors. As an illustration, we measured the PSF of a correctly calibrated point‐scanning confocal microscope and showed that a nearly index‐matched, micron‐sized spherical object is still significantly elongated due to this PSF, which signifies that care has to be taken when determining axial calibration or axial scaling using such particles.     

SELECTION OF A CATION EXCHANGE RESIN TO PRODUCE LACTIC ACID SOLUTIONS FROM WHEY FERMENTATION BROTHS

ABSTRACT

Lactic acid can be made by fermentation from inexpensive cheese whey. The acid is at present fairly costly, however, partly because of the costs of recovery and purification of the acid from the fementation broths. The present study has been undertaken to investigate a process that might reduce these costs. A number of commercial resins have been evaluated as ion exchangers for the production of lactic acid solutions. Amberlite IR-120, a gel strong cationic ion exchanger, was found to be the best resin. The loaded resin was regenerated efficiently. The results suggest that such a process is both technically and economically feasible.     

PHYSICAL–CHEMICAL AND SENSORY QUALITY EVALUATION OF GARLIC CULTIVARS

ABSTRACT

Physical–chemical quality of 14 garlic cultivars grown in Spain was analyzed, and the cultivars were classified into three types: purple, white and Chinese, in order to show the possible differences among them. The most useful instrumental color parameter to discriminate among the different types of garlic was lightness (L*). The high pH value of the purple‐type cultivar Moraluz, and the high content of d ‐glucose, d ‐fructose and total sugars of the Chinese‐type cultivars were quite remarkable. The consumer judges preferred the color and pungency of the purple‐type cultivar Morasol, while Chino Sprint stood out for its intense garlic odor. Finally, correlations between the physicochemical and the sensory parameters were studied. The red color intensity was correlated with lightness (L*) and with hue (h*); pH was correlated with chroma (C*) and moisture percentage was correlated with sucrose content.

PRACTICAL APPLICATIONS

One of the main objectives of this work was to advise growers on the selection of garlic seed. The data obtained in this work was sent to a regional research and advising agronomic center (Technical Agronomic Institute, provincial council of Albacete), where advice was given to local growers concerning the selection of the most adequate seeds, in terms of physical– chemical properties and consumer preference, plus agronomic performance (data not included in this article). The conclusions reached in this study will make an important contribution to the agronomic characterization of the garlic cultivars grown in Spain.