Efficacy and safety of food fortification with calcium among adults in Finland

OBJECTIVE: To examine the efficacy and safety of foods fortified with calcium in the adult population in Finland. DESIGN: A simulation study based on the FINDIET 2002 Survey, which estimated habitual food consumption, dietary supplement use and nutrient intakes using 48-hour recall and two 3-day food records, and an Internet survey of the consumption of fortified foods and dietary supplements. SETTING/PARTICIPANTS: Participants of FINDIET 2002 were 25-64 years old from five areas (n = 2007). Participants of the Internet-based survey (n = 1537) were over 15 years of age from all over the country. RESULTS: If all potentially fortifiable foods were to be fortified with calcium, the proportion of participants with calcium intake below the recommended level (< 800 mg day(-1)) would decrease from 20.3% to 3.0% in men and from 27.8% to 5.6% in women compared with the situation where no foods were fortified. At the same time, the proportion of participants with calcium intake above the tolerable upper intake level (UL, > 2500 mg day(-1)) would increase from 0.6% to 12.7% in men and from 0.1% to 3.8% in women. However, in a probability-based model (11% of all fortifiable foods to be fortified with calcium) the proportion of participants with calcium intake below the recommended level would be 15.7% in men and 23.2% in women. The proportion with intake above the UL in this model would be 1.2% in men and 0.7% in women. CONCLUSIONS: Food fortification would be a relatively effective and safe way to increase the calcium intake of the Finnish adult population.     

Properties of tomato powders as additives for food fortification and stabilization

The antioxidant activities of two freeze-dried tomato powders as additives for food fortification and stabilization were studied. The two tomato powders were obtained from the whole fruit and from the pulp after "serum" separation, respectively. The antioxidant activity was studied by measuring (a) the inhibition of the singlet oxygen-catalyzed oxidation of alpha-linolenic acid, in the presence or absence of copper ions, as a model of the oxidative processes occurring in foods, and (b) the inhibition of xanthine oxidase (XOD)- and myeloperoxidase (MPO)-catalyzed reactions and copper-induced lipid peroxidation. The partial separation of "serum" decreased the freeze-drying time by 50%. The partially fractionated tomato powder had a 60% lower phenolic content and an 11-fold higher lycopene content than the whole tomato powder, on a dry weight basis. Ascorbic acid was almost completely removed by fractionation. Both the powder obtained from the whole tomato and that obtained from the partially fractionated tomato had antioxidant activity in all the model systems used. Based on these results, we conclude that tomato powders have multifunctional properties, which could address the prevention of oxidative degradations both in foods and in vivo. Therefore, tomato can be regarded as source of food additives for fortification and stabilization, even if it is submitted to technological processes that can cause the loss of the more labile hydrophilic antioxidants.     

Interaction among phenols in food fortification: negative synergism on antioxidant capacity

In this work, a study about the consequences of the interaction among phenol compounds on antioxidant capacity is proposed. The antiradical activity evolution of an ethanol solution containing a mixture of three monophenols (catechin, resveratrol, and quercetin) was compared with the trend followed by each single phenol at three different temperatures (22, 37, and 60 degrees C). An initial increase and a following decrease in antioxidant activity were observed for all solutions at the three temperatures. The lower antiradical activity values of the mixture in comparison to the controls during the entire period of storage clearly showed that interaction among these polyphenols promotes a negative synergistic effect on this property.     

Maize meal fortification is associated with improved vitamin A and iron status in adolescents and reduced childhood anaemia in a food aid-dependent refugee population

OBJECTIVE: To assess changes in the Fe and vitamin A status of the population of Nangweshi refugee camp associated with the introduction of maize meal fortification. DESIGN: Pre- and post-intervention study using a longitudinal cohort. SETTING: Nangweshi refugee camp, Zambia. SUBJECTS: Two hundred and twelve adolescents (10-19 years), 157 children (6-59 months) and 118 women (20-49 years) were selected at random by household survey in July 2003 and followed up after 12 months. RESULTS: Maize grain was milled and fortified in two custom-designed mills installed at a central location in the camp and a daily ration of 400 g per person was distributed twice monthly to households as part of the routine food aid ration. During the intervention period mean Hb increased in children (0.87 g/dl; P < 0.001) and adolescents (0.24 g/dl; P = 0.043) but did not increase in women. Anaemia decreased in children by 23.4% (P < 0.001) but there was no significant change in adolescents or women. Serum transferrin receptor (log10-transformed) decreased by -0.082 microg/ml (P = 0.036) indicating an improvement in the Fe status of adolescents but there was no significant decrease in the prevalence of deficiency (-8.5%; P = 0.079). In adolescents, serum retinol increased by 0.16 micromol/l (P < 0.001) and vitamin A deficiency decreased by 26.1% (P < 0.001). CONCLUSIONS: The introduction of fortified maize meal led to a decrease in anaemia in children and a decrease in vitamin A deficiency in adolescents. Centralised, camp-level milling and fortification of maize meal is a feasible and pertinent intervention in food aid operations.     

Challenges in translating scientific evidence into mandatory food fortification policy: an antipodean case study of the folate-neural tube defect relationship

OBJECTIVE: To identify challenges in translating scientific evidence of a nutrient and health relationship into mandatory food fortification policy. DESIGN: A case study approach was used in which available evidence associated with the folate-neural tube defect relationship was reviewed against the Australia New Zealand Food Regulation Ministerial Council's Policy Guideline for mandatory food fortification. RESULTS: Three particular challenges were identified. The first is knowing when and how to act in the face of scientific uncertainty. The second is knowing how to address the special needs of at-risk individuals without compromising the health and safety of the population as a whole. The third is to ensure that a policy is sufficiently monitored and evaluated. CONCLUSIONS: Despite the availability of compelling evidence of a relationship between a particular nutrient and a health outcome, a definitive policy response may not be apparent. Judgement and interpretation inevitably play significant roles in influencing whether and how authorities translate scientific evidence into mandatory food fortification policy. In relation to the case study, it would be prudent to undertake a risk-benefit analysis of policy alternatives and to implement nutrition education activities to promote folic acid supplement use among the target group. Should mandatory folate fortification be implemented, comprehensive monitoring and evaluation of this policy will be essential to know that it is implemented as planned and does more good than harm. In relation to mandatory food fortification policy-making around the world, ongoing national nutrition surveys are required to complement national policy guidelines.     

Use of heme iron concentrate in the fortification of weaning foods

The purpose of this study was to evaluate the technological feasibility of fortifying homogenized weaning food with a porcine heme concentrate. The stability of iron and the organoleptic qualities of two infant weaning foods (a commercial homogenized nonfortified weaning food, NFWF, and the same food fortified with 0.5% of porcine heme concentrate, FWF) were tested throughout 8 months of storage at room temperature and at 37 degrees C. Heme iron decreased with storage time; however, the proportion of this highly available iron was considerably higher in FWF than in NFWF. The addition of heme iron changed significantly the color of the weaning food measured instrumentally, although high temperatures and length of storage time, did not modify Lab, chroma, and hue angle values in both samples. Organoleptic attributes presented a marked stability even in NFWF stored at room temperature and 37 degrees C.     

Vitamin D3 fortification, quantification, and long-term stability in Cheddar and low-fat cheeses

Considering the widespread insufficiency of vitamin D, the fortification of additional foods with vitamin D is warranted. The objective of this research was to assess the feasibility of vitamin D3 fortification in natural hard cheeses. We examined the recovery, distribution, long-term retention, and heat stability of the vitamin in industrially made fortified Cheddar and low-fat cheeses. The results indicated that the vitamin D3 did not degrade during processing, over 1 year of ripening (3-8 degrees C), or after thermal treatment at 232 degrees C for 5 min. Vitamin D3 recovery in the fortified Cheddar and low-fat cheeses were, respectively, 91 and 55% of the vitamin D3 added to the milk used to make each cheese. The remaining vitamin D3 was entrained in the whey. The vitamin D3 was uniformly distributed throughout the blocks of cheese. The fortification process did not alter the yield, chemical composition, or flavor of the Cheddar cheese. We conclude that industrially manufactured Cheddar and low-fat cheeses are suitable for vitamin D3 fortification.     

Interpreting soil and topographic properties to conceptualise hillslope hydrology

The sustainability of agricultural practices is enhanced when vegetation makes optimal use of natural hydrological processes. For example, planting tree belts where slope gradient sharply decreases can enable harvesting of run-on water. This can be beneficial for example in reducing water logging and enhancing tree production. There is a need for rapid and low cost identification of water flow paths and conceptualisation of hillslope hydrology so that local landuse planning can reflect such opportunities. The collection of detailed hillslope hydrological data is prohibitively expensive for such applications and so the use of soil morphology and visual observation of topography and surface condition is evaluated as an alternative.At a study site in south eastern Australia the soil physical profile was described down a hillslope with additional measurements of the hydraulic conductivity, bulk density, cation exchange capacity, electrical conductivity, and particle size distribution of the key horizons. This data was used to identify the perceived significant hydrological flow paths down the hillslope. Measurement of the surface runoff, subsurface lateral flow, and the distribution of saturation measured in piezometers were subsequently used to test the conceptual hydrological model.Soil morphology, particularly the soil colour and presence of redox concretions were useful in identifying the locations and depths where saturation and lateral flow occur. The morphology provides an integrated reflection of the dominant hydrological conditions, but care must be taken to ensure that the observations reflect the current hydrological environment and not relic conditions. Other collaborating information such as the history of geomorphological events at the site, a validation of plausible water sources for the potentially transmitting layers, surface soil condition and landholder observations give improved confidence. Combining soil morphological understanding with visual observations of other site characteristics enabled rapid conceptualisation of hillslope hydrological behaviour as needed for local landuse planning.     

Captive breeding genetics and reintroduction success

Since threatened species are generally incapable of surviving in their current, altered natural environments, many conservation programs require to preserve them through ex situ conservation techniques prior to their reintroduction into the wild. Captive breeding provides species with a benign and stable environment but has the side effect to induce significant evolutionary changes in ways that compromise fitness in natural environments. I developed a model integrating both demographic and genetic processes to simulate a captive-wild population system. The model was used to examine the effect of the relaxation of selection in captivity on the viability of the reintroduced population, in interaction with the reintroduction method and various species characteristics. Results indicate that the duration of the reintroduction project (i.e., time from the foundation of the captive population to the last release event) is the most important determinant of reintroduction success. Success is generally maximized for intermediate project duration allowing to release a sufficient number of individuals, while maintaining the number of generations of relaxed selection to an acceptable level. In cases where a long residence time in captivity cannot be avoided, the use of distinct, genetically independent captive breeding units allows more efficient purging of the genetic load in the reintroduced population, and substantially improves its viability. Overall, the study allows to identify situations in which the genetic cost associated with selection relaxation may overwhelm the demographic benefits of programs.     

The influence of food availability on breeding success of African penguins Spheniscus demersus at Robben Island, South Africa

From 1989 to 2004, the breeding success of African penguins Spheniscus demersus at Robben Island, South Africa was significantly related to estimates of the abundance of both their main prey species, anchovy Engraulis encrasicolus and sardine Sardinops sagax, and to the combined biomass of these species. When the combined spawner biomass of fish prey was less than 2 million ton, pairs fledged an average of 0.46 chicks annually. When it was above 2 million ton, annual breeding success had a mean value of 0.73 chicks per pair. Given previously estimated values of survival and age at first breeding, these levels of breeding success are inadequate to sustain the African penguin population. With the higher level of breeding success, an equilibrium situation might be attained if adult survival could be increased by 6-7% per annum. Attempts to reduce mortality of penguins have included the collection, cleaning and return to the wild of oiled birds, culling of Cape fur seals Arctocephalus pusillus pusillus seen preying on penguins around breeding localities and control of the spread of disease. Management of the purse-seine fishery should ensure adequate escapement of fish to maintain the combined biomass of anchovy and sardine above 2 million ton. The maintenance of suitable breeding habitat and removal of feral predators from breeding localities will also be important in improving breeding success.     

Interpreting morphological features in wetland soils with a hydrologic model

Wetlands in the United States are protected by law and are identified by their hydric soils, wetland hydrology, and vegetation. Hydric soils are easily identified by color characteristics termed hydric soil field indicators, that form under saturated and anaerobic conditions, but wetland hydrology is difficult to assess. This study determines how often seven hydric soil field indicators met wetland hydrology requirements which require a water table be within 30 cm of the surface for 14 days or more during the growing season in over half the years. Studies were conducted at five sites in North Carolina in both wetland and upland plots. Soils ranged from Aquic Paleudults to Typic Haplosaprists across all sites. The water-table simulation model DRAINMOD was calibrated to soil conditions in individual plots. Long-term rainfall data were used with the calibrated models to compute 40 years of daily water table data to represent both wet and dry years. It was found that the hydric soils with field indicators composed of organic materials in layers over 20 cm thick (Histosol and Histic epipedon field indicators) met wetland hydrology requirements each year, and in addition were ponded with water for periods between 67 to 139 days on average each year during the growing season. Plots in mineral soils having the Dark Surface (S7) indicator as well as the Sandy Mucky Mineral (S1) indicator also met the saturation requirements for wetland hydrology every year, and were ponded for only 3 days per year on average. Other mineral soils with an Umbric Surface (F13) or a Depleted Matrix (F3) field indicator met wetland hydrology requirements in approximately 95% of the years, and had water tables within 30 cm of the surface for 40 days per year on average. The Redox Depressions (F8) field indicator occurred in a small depression that was saturated for 87% of the year for periods averaging approximately 30 days. These results showed that hydric soil field indicators can be calibrated to long-term water table data that will allow precise assessments of wetland hydrology on-site.     

中国水资源和粮食安全问题探讨

中国是世界人口最多的发展中国家,用占全球7%的土地、8%的淡水养活占全球22%的人口.但随着人口的持续增长,气候干旱和生态境破坏以及污染的不断扩大和加重,水和耕地资源的不断减少,中国在水资源和粮食安全方面将面临巨大的压力与挑战.中国干旱半干旱的西北地区,有70%左右的贫困人口,粮食安全问题长期存在,经济发展缓慢.目前中国政府实施的西部大开发战略,减免农业税费,增加经济投入和水利工程等建设项目,是解决西北地区贫困的关键.