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Texture analysis is a well-established analytical technique in the food industry for evaluating the mechanical and physical characteristics of both raw ingredients and finished products. Instrumental mechanical properties of table grapes, acquired using universal testing machines equipped with specific probes, may be of interest in the viticulture and postharvest sectors to recognize the potential of each variety and help satisfy market requirements. The measured parameters are related to some sensory properties and, therefore, indirectly to consumer acceptability of the product. As texture analysis is a rapid and low-cost analytical technique, it can also be favorably applied in enology as a routine tool for monitoring winegrape quality. Among the different mechanical parameters measurable, berry skin thickness and hardness are indices that reflect anthocyanin extractability and dehydration kinetics with adequate reliability. This review collects the most recent research results from grape texture studies, emphasizes the potentiality and limits of this analytical technique when applied to grape studies, and highlights trends that require further understanding.

The role of interferon in the pathogenesis of encephalomyocarditis (EMC) virus infection was determined by treating mice with potent, partially purified sheep anti-mouse interferon globulin. In control mice, EMC virus was present in low titers in various visceral organs but attained high titers in the brain towards the 4th to 5th day, at which time mice died with signs of central nervous system disease. In mice treated with anti-mouse interferon globulin, virus was present in high titer in visceral organs 24--36 h after viral inoculation and virtually all mice were dead by 45 h. This rapid evolution of EMC virus infection was not observed in mice treated with the globulin fraction prepared from a normal sheep, from a sheep exhibiting a low anti-mouse interferon-neutralizing titer, nor from a sheep having a high titer of antibody to human leukocyte interferon. The experimental results indicated that anti-interferon globulin neutralized the interferon liberated by virus-infected cells, thus permitting extensive virus multiplication in several visceral organs. We conclude that interferon is an important early component of host resistance to this virus infection.

There is scant literature on the assessment and validation of methods for monitoring grape texture during ripening. There is a distinct lack of information from published work on the correct procedures to set up texture method. If the measurement of grape texture is to be used for assessing ripeness and further extended to the assessment of polyphenol extractability potential, the relationship between physicochemical parameters and sensory descriptors should be evaluated as a matter of importance. In this work, the physical properties of grape texture during ripening were addressed by an assessment of the relationship between the methods of double compression and puncture tests. The second part of the study reported here applied the methods developed in the first year to grapes sampled in the following year. The results showed that the mechanical texture measurements were able to discriminate grapes coming from different parcels and correlations were found between texture parameters and sensory descriptors. PRACTICAL APPLICATIONSThis paper defines the measurement conditions for monitoring grape texture, particularly during ripening. These established methodologies provide enologists with the tools to monitor the progress of grape maturity, and these mechanical methods compare favorably with the expensive and timeconsuming classical methods. These established methodologies could also be 1 Corresponding Journal of Texture Studies 40 (2009) 511-535. © 2009 used to highlight important information on grape evolution during ripening and help to provide better insight on the choice of the preferred/ideal harvest date. These tools, providing enologists with data on the evolution of fruit texture, could be used to help select more suitable winemaking processes as well, as the extractability of compounds present in the fruit is probably linked to its texture.

The effect of potent sheep anti-mouse interferon globulin was investigated in several different experimental virus diseases of mice. In anti-interferon globulin-treated mice infected intraperitoneally with herpes simplex virus (HSV) type I, the latent period was shortened, and the overall LD50 was increased several hundredfold compared to virus-infected control mice. When HSV was inoculated subcutaneously all anti-interferon globulin-treated mice died, whereas only 5% of virus-infected control mice died. Subsequent treatment with anti-interferon globulin of previously HSV-infected mice did not result in reactivation of HSV. Treatment of adult mice with anti-interferon globulin resulted in an earlier appearance of MSV-induced tumors, a greater number of mice bearing tumors, an increase in tumor size, and an increase in the duration of tumors. All tumors eventually regressed despite reinjection of anti-interferon globulin. Anti-interferon globulin treatment resulted in a rapid onset of disease and death in adult mice inoculated (intranasal) with VSV and in newborn mice infected with NDV. Anti-interferon globulin exerted no effect on the course of influenza virus infection of mice. We conclude that the early production of interferon is an importane element in the response of the mouse to several viruses exhibiting different pathogeneses.