Food fermentations: microorganisms with technological beneficial use.

Microbial food cultures have directly or indirectly come under various regulatory frameworks in the course of the last decades. Several of those regulatory frameworks put emphasis on "the history of use", "traditional food", or "general recognition of safety". Authoritative lists of microorganisms with a documented use in food have therefore come into high demand. One such list was published in 2002 as a result of a joint project between the International Dairy Federation (IDF) and the European Food and Feed Cultures Association (EFFCA). The "2002 IDF inventory" has become a de facto reference for food cultures in practical use. However, as the focus mainly was on commercially available dairy cultures, there was an unmet need for a list with a wider scope. We present an updated inventory of microorganisms used in food fermentations covering a wide range of food matrices (dairy, meat, fish, vegetables, legumes, cereals, beverages, and vinegar). We have also reviewed and updated the taxonomy of the microorganisms used in food fermentations in order to bring the taxonomy in agreement with the current standing in nomenclature.

Minimising the population risk of micronutrient deficiency and over-consumption: a new approach using selenium as an example.

BACKGROUND: At the present time the recommended daily intake or allowance (RDA) and the safe upper level (UL) of intake of micronutrients are given as single values. The recommended daily intake is considered to cover the requirements of 97.5% of the population while the safe upper level is a value for the whole population. These values provide only limited guidance to risk managers. AIM OF THE STUDY AND METHODS: A method has been developed recently which models the relationships between intake and risks of either deficiency or excess using an observed incidence for each effect and population distribution characteristics. Using this model it is possible to formulate advice to risk managers on the incidence (prevalence) of adverse effects, due to either deficiency or excess, at different levels of intake. Application of the model to the data used to derive the RDA and UL for selenium shows that it can predict the impact of changes in nutrient intake on the balance between benefit (absence of deficiency) and risk (development of toxicity). RESULTS AND CONCLUSIONS: Application of the model has illustrated the utility of this approach, but highlighted the need for a comprehensive evaluation of the data and a critical appraisal of the validity of the relationships that are analyzed. In addition, the derived incidences will usually relate to effects with different biological or health impacts, so that the final balance between benefit and risk should be developed by a dialogue between the risk assessor and the risk manager.

PASSCLAIM--body weight regulation, insulin sensitivity and diabetes risk.

BACKGROUND: Insulin sensitivity is a key function in human metabolism because it has a crucial role in the development of disease that are increasingly common in modern society. Impaired insulin sensitivity is an important determinant of type 2 diabetes; moreover, it has been proposed as an independent risk factor for cardiovascular disease. Thus, reduced insulin sensitivity is strongly associated with the metabolic syndrome, which represents a cluster of metabolic abnormalities and cardiovascular risk factor. Insulin sensitivity can be modulated by different environmental factors, including dietary habits. Obesity, especially if associated with abdominal adiposity, impairs insulin-sensitivity while physical activity can improve it; however, the composition of the habitual diet is clearly an important regulator of this function. AIM: To evaluate methodologies and markers that can be used to substantiate existing and potential claims of beneficial effects of foods on relevant functions connected with body fat deposition, insulin sensitivity and blood glucose regulation. RESULTS: We have reviewed the scientific basis for existing and potential claims, based not only on modifications of the target functions (body fat deposition, insulin sensitivity and blood glucose regulation) but also on modifications of other relevant associated functions (energy intake, energy expenditure, fat storage and oxidation, lipotoxicity, body fat composition, inflammation, oxidative stress, vascular function, glucose production and utilization). In this context we have identified a number of markers and evaluated appropriate method to measure and validate them. CONCLUSIONS: Relevant functions contributing to overweight, the metabolic syndrome and diabetes have been identified. The evidence reviewed indicates that in this field the link between nutrition, biological responses and diseases is clearly established. Therefore, there is a strong potential to develop functional food science. The major gap in the evidence continues to be the lack of diet based intervention trials of sufficient duration to be relevant for affecting the natural history of these conditions.

PASSCLAIM--mental state and performance.

BACKGROUND: The intake of food and drink can influence brain functions, which in turn may have effects on mental state and performance. Therefore, in principle claims to improve mood or specific aspects of cognitive performance by the consumption of functional foods are possible and indeed are currently found on the market. AIM: The paper reviews existing methodologies, which may be used to substantiate and validate such claims of desirable effects of foods on mental state and performance. RESULTS: Mood, arousal, activation, vigilance, attention, sleep, motivation, effort, perception, memory and intelligence have been identified as relevant aspects of mental state and performance. The basic scientific concepts within this field as well as the methodologies to measure these concepts have been reviewed and described. CONCLUSIONS: From this review it is concluded that, in principle, the phenomena in these fields are no different to those in other fields of life science. The scientific methods and protocols described in this report can positively demonstrate the effects of foods on mental state and performance in a scientifically valid way. A claim on mental state and performance like other claims must be based on scientific evidence. This report confirms that methodologies do exist to generate sound scientific evidence in this area. Therefore, claims on the enhancement of specific mental functions can and should be substantiated and validated using the methodologies described in this review.

PASSCLAIM--diet-related cancer.

BACKGROUND: The role of dietary factors in the aetiology of human cancer is an area, which has attracted intense interest in recent years. The suggestion that approximately one third of all cancers may be caused by an 'inappropriate' balance of food components has led to the attractive contention that we can significantly decrease cancer incidence through dietary recommendations and a change in dietary habits in populations. Thus, a key issue must be to establish clear criteria, which must be met in order to be able to make 'cancer risk reduction' claims for food components. In this area, the one true marker is the malignant human tumour, which for practical reasons is usually not accessible to claims. In its absence, we must rely on alternative markers--biomarkers/surrogate endpoints. This paper mainly deals with the link of these biomarkers to the endpoint tumour and their usefulness for making claims. Some claims have been made based on epidemiological studies. AIM: Can we identify targets/ biomarkers in the chain of events from initial 'exposure' to overt malignant tumour, whose modification can be used to make 'anticancer' claims for food components? RESULTS: We identified 18 targets/markers in the above chain of events whose modification 'have the potential' to be used for 'reduction of cancer risk' claims for food components. These targets/markers fall under 5 broad headings: tumours and preneoplastic changes; cellular targets/markers; gut luminal markers; angiogenesis and metastasis; carcinogen metabolising enzymes; genetic events. CONCLUSIONS: The strongest markers presently available are precancerous lesions (e. g. polyps or aberrant crypt foci) in humans and precancerous lesions and tumours in animal models. The only marker that presently can be used for a 'reduction of disease risk' claim (type B) for food components is 'polyp recurrence'. Type B claims cannot be made on the basis of results in animal models. All of the other biomarkers examined presently lack validation against the 'true endpoint', the tumour, and thus cannot be used for type B claims. 'Reduction of disease risk' claims in the area of 'diet-related cancer' should be based primarily on human intervention studies using relevant/acceptable endpoints. An important area for future research will be the validation of these surrogate endpoints.

PASSCLAIM--gut health and immunity.

BACKGROUND: The gut and immune system form a complex integrated structure that has evolved to provide effective digestion and defence against ingested toxins and pathogenic bacteria. However, great variation exists in what is considered normal healthy gut and immune function. Thus, whilst it is possible to measure many aspects of digestion and immunity, it is more difficult to interpret the benefits to individuals of variation within what is considered to be a normal range. Nevertheless, it is important to set standards for optimal function for use both by the consumer, industry and those concerned with the public health. The digestive tract is most frequently the object of functional and health claims and a large market already exists for gut-functional foods worldwide. AIM: To define normal function of the gut and immune system and describe available methods of measuring it. RESULTS: We have defined normal bowel habit and transit time, identified their role as risk factors for disease and how they may be measured. Similarly, we have tried to define what is a healthy gut flora in terms of the dominant genera and their metabolism and listed the many, varied and novel methods for determining these parameters. It has proved less easy to provide boundaries for what constitutes optimal or improved gastric emptying, gut motility, nutrient and water absorption and the function of organs such as the liver, gallbladder and pancreas. The many tests of these functions are described. We have discussed gastrointestinal well being. Sensations arising from the gut can be both pleasant and unpleasant. However, the characteristics of well being are ill defined and merge imperceptibly from acceptable to unacceptable, a state that is subjective. Nevertheless, we feel this is an important area for future work and method development. The immune system is even more difficult to make quantitative judgements about. When it is defective, then clinical problems ensure, but this is an uncommon state. The innate and adaptive immune systems work synergistically together and comprise many cellular and humoral factors. The adaptive system is extremely sophisticated and between the two arms of immunity there is great redundancy, which provides robust defences. New aspects of immune function are discovered regularly. It is not clear whether immune function can be "improved". Measuring aspects of immune function is possible but there is no one test that will define either the status or functional capacity of the immune system. Human studies are often limited by the ability to sample only blood or secretions such as saliva but it should be remembered that only 2% of lymphocytes circulate at any given time, which limits interpretation of data. We recommend assessing the functional capacity of the immune system by: measuring specific cell functions ex vivo. measuring in vivo responses to challenge, e. g. change in antibody in blood or response to antigens. determining the incidence and severity of infection in target populations during naturally occurring episodes or in response to attenuated pathogens.