Økologiske fødevarers betydning for sundheden

I årevis har det været diskuteret, hvorvidt økologisk producerede fødevarer er sundere end konventionelle. Indtil videre er der ikke noget, der underbygger, at de er det. Ofte måles der på indholdet i selve fødevarerne, men det er en almindelig misforståelse, at man sådan lige kan måle sig frem til sundhedsværdien af en fødevare

Cheese intake lowers plasma cholesterol concentrations without increasing bile acid excretion

AbstractPurposeCheese is a dairy product with high calcium content. It has been suggested that calcium intake may increase fecal excretion of bile acids that would cause a regeneration of bile acids from hepatic cholesterol and thereby result in a lowering of plasma cholesterol concentrations. We aimed to test this hypothesis by assessing bile acid and calcium concentrations in fecal samples from humans after intake of cheese and butter.MethodsThe study was a randomized, 2 × 6 weeks crossover, dietary intervention study including 23 men and women who replaced part of their habitual dietary fat intake with 13% energy from cheese or butter.ResultsAfter 6 weeks of intervention cheese resulted in higher amounts of calcium excreted in feces compared to butter. However, no difference was observed in fecal bile acid output despite lower serum total, LDL and HDL cholesterol concentrations observed with cheese intake.ConclusionWe were not able to confirm the hypothesis that calcium from cheese increases the excretion of fecal bile acids. Therefore, the mechanisms responsible for the lowering of cholesterol concentrations with cheese compared to butter intake remains unresolved

Dietary carbohydrate source influences molecular fingerprints of the rat faecal microbiota

BACKGROUND: A study was designed to elucidate effects of selected carbohydrates on composition and activity of the intestinal microbiota. Five groups of eight rats were fed a western type diet containing cornstarch (reference group), sucrose, potato starch, inulin (a long- chained fructan) or oligofructose (a short-chained fructan). Fructans are, opposite sucrose and starches, not digestible by mammalian gut enzymes, but are known to be fermentable by specific bacteria in the large intestine. RESULTS: Animals fed with diets containing potato starch, or either of the fructans had a significantly (p < 0.05) higher caecal weight and lower caecal pH when compared to the reference group, indicating increased fermentation. Selective cultivation from faeces revealed a higher amount of lactic acid bacteria cultivable on Rogosa agar in these animals. Additionally, the fructan groups had a lower amount of coliform bacteria in faeces. In the inulin and oligofructose groups, higher levels of butyrate and propionate, respectively, were measured. Principal Component Analysis of profiles of the faecal microbiota obtained by Denaturing Gradient Gel Electrophoresis (DGGE) of PCR amplified bacterial 16S rRNA genes as well as of Reverse Transcriptase-PCR amplified bacterial 16S rRNA resulted in different phylogenetic profiles for each of the five animal groups as revealed by Principal Component Analysis (PCA) of band patterns. CONCLUSION: Even though sucrose and cornstarch are both easily digestible and are not expected to reach the large intestine, the DGGE band patterns obtained indicated that these carbohydrates indeed affected the composition of bacteria in the large gut. Also the two fructans resulted in completely different molecular fingerprints of the faecal microbiota, indicating that even though they are chemically similar, different intestinal bacteria ferment them. Comparison of DNA-based and RNA-based profiles suggested that two species within the phylum Bacteroidetes were not abundant in numbers but had a particularly high ribosome content in the animals fed with inulin

<em>In vitro</em> liberation of carotenoids from spinach and Asia Salads after different domestic kitchen procedures

AbstractGreen-leafy vegetables are rich in nutritionally important constituents including carotenoids. Their potential health benefits depend among others on their liberation from the plant matrix. The aim of the present study was to evaluate the effect of particle size and heat treatments on lutein and β-carotene liberation from spinach and Asia salads by applying an in vitro digestion protocol and UHPLC analysis. Reduction of particle size resulted in a three- to fourfold increase in liberation of lutein and β-carotene when comparing whole leaf and puree preparations of spinach. However, this positive effect was shown to be nullified by the severe heat impact during stir-frying of minced spinach, showing that domestic treatments need to be chosen carefully to maximise carotenoid liberation. Steaming significantly improved lutein liberation from Asia salads, but had no or a negative effect in spinach samples, possibly due to differences in liberation or degradation between the two plant matrices