Biogenic Amines in Wine: Understanding the Headache

The presence of biogenic amines in wine is becoming increasingly important to consumers and producers alike,due to the potential threats of toxicity to humans and consequent trade implications. In the scientific field, biogenicamines have the potential to be applied as indicators of food spoilage and/or authenticity. Biogenic amines can beformed from their respective amino acid precursors by various microorganisms present in the wine, at any stageof production, ageing or storage. To understand the large number of factors that could influence the formation ofbiogenic amines, the chemical, biochemical, enzymatic and genetic properties relating to these compounds have tobe considered. Analytical and molecular methods to detect biogenic amines in wine, as well as possibilities that couldenable better control over their production levels in wine will also be explored in this review

Involuntary sterilisation of HIV-positive women in South Africa: A current legal perspective

This article examines the reality of HIV-positive women being subjected to perpetual stigmatisation as a result of involuntary sterilisation practices. The reproductive autonomy and dignity of HIV-positive persons is protected by various constitutional provisions, and a legal framework providing for the requirement of informed consent, as well as the prohibition of discrimination on the grounds of HIV status. This article considers the issues of both informed consent and discrimination in the context of the practice of involuntary sterilisation of HIV positive women. The article considers the legal framework in light of the physical, emotional, social and cultural implications for HIV-positive women who are subjected to involuntary sterilisation

The spatial development strategy for the Western Cape

This article gives readers a preview of a document which will be published in the next few weeks by the Department of Environmental Planning and Energy setting out Government policy as regards the spatial development of the Western Cape. This development strategy was announced by the Minister of Environmental Planning and Energy on 6 June 1979 by means of a press statement in which the main considerations in detennining the guide lines for the physical development of the Western Cape were set out

Situational reasoning for road driving in an urban environment

Robot navigation in urban environments requires situational reasoning. Given the complexity of the environment and the behavior specified by traffic rules, it is necessary to recognize the current situation to impose the correct traffic rules. In an attempt to manage the complexity of the situational reasoning subsystem, this paper describes a finite state machine model to govern the situational reasoning process. The logic state machine and its interaction with the planning system are discussed. The approach was implemented on Alice, Team Caltech’s entry into the 2007 DARPA Urban Challenge. Results from the qualifying rounds are discussed. The approach is validated and the shortcomings of the implementation are identified

The Effect of Micro-oxygenation on the Phenolic Composition, Quality and Aerobic Wine-Spoilage Microorganisms of Different South African Red Wines

The effect of micro-oxygenation treatments on the composition of different South African red wines was evaluated.  In some wines, micro-oxygenation led to an increase in colour density, with a corresponding change in colour, due to the formation of polymeric pigments. This increase also led to the red colour becoming more resistant to the bleaching effect of SO2. Micro-oxygenation also seemed to be more effective in increasing the colour densities of younger red wines than the older ones, although total red pigments were found to be highest in an older red wine that had received micro-oxygenation. Differences in the gelatine index were also observed over time. The micro-oxygenated and barrel-matured wines also had lower concentrations of catechin and the procyanidin B1, and showed a corresponding increase in polymeric pigment and polymeric phenols. Micro-oxygenation led to higher acetic acid bacteria counts, although no increase in volatile acidity was observed in these wines. A tasting panel preferredyounger red wines that had undergone micro-oxygenation. In an older red wine prolonged micro-oxygenation led to the wine becoming over-aged, with an increase in the barnyard/medicinal character, which corresponded with an increase in Brettanomyces counts. Micro-oxygenation can be used to increase the quality of young red wines, but further research is needed in this area

Oxygen in Must and Wine: A review

Oxygen can play an important role during the winemaking process. It can influence the composition and quality of the must and wine. Phenolic compounds are the main substrates for oxidation in must and wine. Oxygen addition leads to colour changes and the polymerisation of phenolic molecules in wine. Oxygen can, however, also influence the flavour and microbial composition of wine drastically, with certain off-flavours being formed and spoilage micro-organisms able to grow at too high oxygen additions to wine. A state-of-the-art, up-to-date review on the effects of oxygen in must and wine has, however, not been published recently. This review focuses on the effects of oxygen in must, during alcoholic fermentation, extended lees contact and during ageing of white and red wines. The effects it has on acetic acid bacteria and Brettanomyces are also discussed, as well as micro-oxygenation, a relative new technique used in wine production

Microbial Spoilage and Preservation of Wine: Using Weapons from Nature's Own Arsenal -A Review

The winemaking process includes multiple stages at which microbial spoilage can occur, altering the quality and hygienic status of the wine and rendering it unacceptable. The major spoilage organisms include species and strains of the yeast genera Brettanomyces, Candida, Hanseniaspora, Pichia, Zygosaccharomyces etc., the lactic acid bacterial genera Lactobacillus, Leuconostoc, Pediococcus, etc. and the acetic acid bacterial genera Acetobacter and Gluconobacter. The faults caused include bitterness and off.flavours (mousiness, ester taint, phenolic, vinegary, buttery, geranium tone), and cosmetic problems such as turbidity, viscosity, sediment and film formation. These spoilage organisms can also affect the wholesomeness of wine by producing biogenic amines and precursors of ethyl carbamate. The judicious use of chemical preservatives such as sulphur dioxide (S02) during the winemaking process decreases the risk of microbial spoilage, but strains vary considerably in their S02 sensitivity. There is,moreover, mounting consumer bias against chemical preservatives, and this review focuses on the possible use of biopreservatives in complying with the consumers' demand for "clean and green" products

The eye in systemic disease

The eye is a unique organ which is often involved in systemic disease. Patients with systemic disease may first present with eye pathology, and patients with known systemic illnesses may need to have their eyes specifically checked for ocular complications. It is thus useful for the physician to be familiar with the ocular manifestations of common systemic diseases at primary care level. Diseases like diabetes, herpes zoster ophthalmicus and thyroid ophthalmopathy often involve the eyes, and if the eye signs are not identified early, the visual consequences can be devastating. Diabetic retinopathy is an important cause of blindness in this country. These, as well as common ocular manifestations of human immunodeficiency virus/acquired immune deficiency syndrome, syphilis, some dermatological conditions and the ocular side-effects of certaindrugs, are discussed in this article. It is important for the primary care physician to be familiar with the spectrum of ocular involvement in systemic diseases since appropriate intervention and referral can be sight saving for the patient

The eye in systemic disease

The eye is a unique organ which is often involved in systemic disease. Patients with systemic disease may first present with eye pathology, and patients with known systemic illnesses may need to have their eyes specifically checked for ocular complications. It is thus useful for the physician to be familiar with the ocular manifestations of common systemic diseases at primary care level. Diseases like diabetes, herpes zoster ophthalmicus and thyroid ophthalmopathy often involve the eyes, and if the eye signs are not identified early, the visual consequences can be devastating. Diabetic retinopathy is an important cause of blindness in this country. These, as well as common ocular manifestations of human immunodeficiency virus/acquired immune deficiency syndrome, syphilis, some dermatological conditions and the ocular side-effects of certain drugs, are discussed in this article. It is important for the primary care physician to be familiar with the spectrum of ocular involvement in systemic diseases since appropriate intervention and referral can be sight saving for the patient

Correlations between South African Red Grape and Wine Colour and Phenolic Composition: Comparing the Glories, Iland and Bovine Serum Albumin Tannin Precipitation Methods

Phenolic compounds in red grapes might give an indication of phenolic and colour compositions ofthe resulting wine. This work compared the Glories, Iland and Bovine Serum Albumin (BSA) tanninprecipitation methods for phenolic characterization of South African Pinotage, Merlot, Shiraz andCabernet Sauvignon red grape samples (n=31). Significant positive correlations were found for certainphenolic characteristics in the grapes measured by these methods. Levels of phenolic compounds in thegrapes and correlating wines were in line with literature. Merlot samples often associated more with higherconcentrations of seed tannins, which were also reflected in the wines. Significant correlations were alsofound with the colour characteristics of the resulting wines and some anthocyanin related measurementsin the grapes with the Glories and Iland methods, with the latter correlating slightly better. Significantpositive correlations were also found between grape and wine tannins as measured with the BSA method.However, malolactic fermentation changed some of these correlations and this needs to be investigatedfurther. This work might give wine producers as well as wine analyses laboratories valuable informationregarding the suitability of these methods to characterize the phenolic composition of South African redgrapes and their resulting wines