Microscopia elettronica a scansione per l’analisi morfologica e ultrastrutturale di cariossidi di frumento duro

Abstract

Cereals are an important source of carbohydrates in the human contributing to a certain extent also to the need of protein. They constitute a rich source of both nonstarch polysaccharides (dietary fiber) and starch, which together comprise 70-77% of kernel. The Guidelines for a Healthy Diet in Italy define the opportunity to take, on a daily basis, at least 60% of energy from carbohydrates, and particularly 45% from complex carbohydrates. In Italy, especially in Sicily, these nutrients are contained in traditional food as pasta and bread made starting from durum wheat as grow material. Recently, especially in the bigger towns, there is also widespread consumption of bread made with soft wheat.2,3 In the last decade, consumer behavior is changing in Italy4 and it is clear a trend of decline in consumption of pasta and bread, instead there is an opposite trend for the consumption of products considered as a substitute for bread (brioches, crackers, biscuits, and other baked goods). It is evident how the nutritional profile of the latter products deviates from the bread due to the fat content, that ranges from 5 to 20%. It is also known as the derivatives of durum wheat, preferably whole grain products, are also characterized by a lower glycemic index than products of soft wheat. So cereals are a key component to set a proper diet. Some studies also report that influence of a regular and correct consumption of cereals may contribute to reach and to maintain normal weight.5 In 2011 was carried out investigations with the aim to understand better the relationship and the presence of cereals in the diet of preteen. Moreover, it is known as in Sicily, as well as other areas of southern Europe, there is a serious problem of childhood obesity,6,7 mainly related to lifestyles considered incorrect and a lower level of education of the population than other European areas that do not registers this phenomenon. The investigation involved a sample of 1335 subjects, aged between 10 and 13 years, identified through the involvement of 62 schools distributed throughout the region. The sample involved in the investigation was extrapolated according to a stratification that has taken into account the size of the population under study, age ,sex, and distribution by province. For each individual was recorded during the first half of December 2011, thanks to personnel appropriately trained to collect information in a standardized way, a 24-h recall questionnaire (noting the foods eaten in the last 24 hours from the individual). In addition to the parents were asked to complete a questionnaire on the frequency to record information on lifestyle, frequency of intake of cereals. For each individual was recorded weight (kg), height (cm) and body mass index (BMI, Body Mass Index), according to the standards proposed by the International Obesity Task Force.8 About frequency of the conditions of the weight of the individuals in the sample, the results have confirmed what was already mentioned by other authors for Sicily.6,7 Results of the study shows as the population sample, in the various daily meals, have not a correct relationship with cereals, considering the models known for the Mediterranean population. In particular, it is clear the high frequency of subjects who have not took any kind of cereals at breakfast (n=699, 52%) or at morning-snack (n=396, 30%). Moreover 17% of individuals (n=228) has neither taken any kind of breakfast cereal nor at morning-snack; these individuals have access to the primary source of complex carbohydrates, needed daily, only with lunch. The individuals who regularly eat pasta are characterized by a lower Body Mass Index than those who do not consume habitually; the same is for those who regularly take breakfast, according as noted by other authors in specific studies conducted in the Mediterranean basin,9 and for individuals who have eaten at least one type of cereal f