Abstract
Port Wine ageing process is very important to produce the most appreciated and expensive wines from the class. The process takes decades to accomplish and involves particular techniques which are taken inside refrigerated cellars. Different wines pass through such process to produce 10 year, 20 year, 30 year and 40 year Ports. There are no documented data about color or turbidity evolution during the ageing process. We decided to verify the states of color and spectral turbidity of different aged Gold white port wine. The acquired results show a spectral evolution on transmition and scattered radiation along with color modification which are a close and direct consequence of adopted corrective measures. In measuring the four samples, we have used our spectronephelometer with optical fiber tips to illuminate sample and to acquire transmitted or scattered radiation. Transmition results were calibrated with a standard spectrophotometer at our laboratory, and scattered spectra were measured considering a system calibration with ISO12103 standard dust. We are aware that the four samples were harvested in different years, but the wine type is the same and the ageing process does not differ from one sample to another.

Abstract
Complete optical characterization of biological tissue is desirable to develop clinical methods using optical technologies. Particularly, to develop optical clearing methods in biological tissues, it is necessary to know the composition of the tissue, the percentage of each constituent and corresponding refractive indexes. To obtain such information for rat muscle, we used a simple method to characterize tissue constituents for both content percentage and refractive index. The study consisted on measuring mass with a precision weighting scale and the refractive index with an Abbe refractometer during tissue dehydration. With the collected data, we used a theoretical model to calculate the refractive index and percentage for both interstitial fluid and solid part of the rat muscle. The results obtained are in good agreement with data published by other authors, and were considered of vital information for the optical clearing studies that we planned to perform.

Abstract

Abstract
Spectronephelometric measurement techniques are :in the order of the day. We can apply these techniques to monitor the production of consumable fluids and to verify their quality. Products like Wine, Beer and Olive Oil for instance, are widely consumed over the world. These products do have a major role in people's dietary habits and their quality is of greater concern from day to day. If we can make use of a monitoring system that is able to perform measurements in situ, on line and in real time, then we will obviously have the capacity to improve quality. Particles that are suspended in consumable fluid samples interact with radiation by scattering it in almost all directions. If we can detect this scattered radiation, then we have information on the suspended particles. Making use on some Physical relations, we can transpose this information to physical parameters like Color and Turbidity.

Abstract
The main purpose of this research was to create a portable equipment capable of measuring colour and turbidity during production of port wine. Actually, human, chemical and colour analysis are performed in key production stages for quality control. Several wine transformation processes are done without any kind of control. By using a fibre optic illuminator with a tungsten/halogen light source and a small spectrometer with fibre optic input, it was possible to perform angular measurements in wine samples. We have adapted these optical devices with a specially designed mechanical equipment which allows the passage of the wine during production. The spectral measurements were acquired in four different angular positions in a bypass of the mechanical support. This way we could determine colour coordinates and spectral transmittance and turbidity for three stages of a Ruby production. The entire equipment assembly had been previously calibrated in terms of colour and turbidity determination. The obtained results are in agreement with wine transformations between measurements, showing a small variation in colour and a high diminishing in spectral turbidity when filtration was performed. Transmittance has also increased after filtration turning the wine more limpid as it should be for human appreciation.

Abstract
Computational methods have been used with great application to biomedical optics. The events created by the interaction of radiation with biological materials can easily be translated to computer languages with the objective of producing simulation techniques to be used prior to physical intervention. The addition of biocompatible and hyper osmotic agents to several types of biological tissues has proven the enhancement of transparency to radiation flux by reduction of material's optical properties. The evolutionary behavior of the agent's action in the tissue samples before saturation has been observed by numerous researchers but has never been described mathematically. In the present work we will describe the application of Monte Carlo simulation to estimate the evolutionary states of optical transparency of biological tissues when immersed in an osmotic solution. We begin our study with typical values for the optical properties of rabbit muscle and proceed by reducing the absorption and scattering coefficients independently and simultaneously. The results show the number of transmitted, absorbed, scattered and reflected photons in different stages of the action of a generic osmotic agent over a small and well defined tissue sample.