Anita Fechner

Effects of polydextrose supplementation on different faecal parameters in healthy volunteers

Polydextrose (PDX) is a non-digestible polysaccharide providing beneficial effects on bowel health. The aim of the study was to show prebiotic effects of PDX. A placebo-controlled, randomized intervention study with PDX supplementation (8 g/day) was conducted in 45 healthy subjects. The effects of PDX on stool weight, orofaecal transit time, consistency of stool (Bristol stool form scale), short-chain fatty acid production, pH value, neutral sterol and bile acid excretion and faecal microbiota were evaluated. It was found that supplementation of PDX shortened the orofaecal transit time significantly. Furthermore, ingestion of PDX resulted in a decreased pH value and in significant changes in bile acid and neutral sterol excretion. PDX had no effects on stool weight, concentrations of the abundant short-chain fatty acids (acetate, propionate) and faecal contents of Lactobacillus acidophilus and Bifidobacterium lactis. In conclusion, PDX is able to shorten the orofaecal transit time and to improve stool consistency in subjects suffering from constipation.

Consuming a mixed diet enriched with lupin protein beneficially affects plasma lipids in hypercholesterolemic subjects: A randomized controlled trial

BACKGROUND & AIMS The objectives of this study were to assess whether 25 g/d lupin protein, integrated into a mixed diet, might affect cardiovascular risk factors and whether l-arginine was responsible for these effects. METHODS Seventy-two hypercholesterolemic subjects participated in the randomized, controlled, double-blind three-phase crossover study. They were assigned to three diets with 25 g/d lupin protein (LP), milk protein (MP) or milk protein plus 1.6 g/d arginine (MPA) each for 28 d in a random order interrupted by 6-week washout periods. Lupin protein and the comparator milk protein were incorporated into complex food products (bread, roll, sausage, and vegetarian spread). Arginine was administered via capsules. Sixty-eight subjects were included in final analyses. RESULTS Compared with MP, LDL cholesterol was significantly lower after LP. Compared with MP and MPA, homocysteine was significantly lower after LP. Compared with baseline, concentrations of total, LDL, and HDL cholesterol significantly decreased after LP and MPA. Triacylglycerols and uric acid significantly decreased after LP. The relative changes in total and LDL cholesterol were significantly greater for subjects with severe hypercholesterolemia (>6.6 mmol/L) than those with moderate hypercholesterolemia (5.2-6.6 mmol/L). CONCLUSIONS The present study showed for the first time that incorporation of 25 g/d of lupin protein into a variety of complex food products lowers total and LDL cholesterol, triacylglycerols, homocysteine, and uric acid in hypercholesterolemic subjects. The hypocholesterolemic effect is stronger in subjects with severe hypercholesterolemia. Arginine might be responsible for some, but not all of the beneficial effects of lupin protein. This trial was registered at http://clinicaltrials.gov (study ID number NCT01598649).

Nutritional evaluation of rapeseed protein compared to soy protein for quality, plasma amino acids, and nitrogen balance--a randomized cross-over intervention study in humans.

BACKGROUND & AIMS Plant proteins such as rapeseed have received little attention for human nutrition due to their high level of antinutritive compounds. Today, newer technologies can eliminate such compounds. The present intervention study aimed to evaluate nutritional and physiological properties of two manufactured canola proteins with special focus on their bioavailability in humans. METHODS 28 healthy male subjects (ø 25 years) consumed 30.0 g protein (canola protein isolate--CPI, canola protein hydrolyzate--CPH or soy protein isolate--SPI) in a randomized, double-blind, cross-over study. Blood samples were regularly drawn over the 8-h postprandial period and a 24-h urine sample was collected. RESULTS True digestibility of the canola proteins determined in a separate rat assay showed 93.3% for CPI and 97.3% for CPH. In humans, consumption of either 30.0 g canola protein or soy protein mixed in a drink led to significant increases in plasma amino acids after 62.3 and 83.6 min, respectively. While the CPH produced an earlier response compared to CPI and SPI, total amino acid response (AUC for 8 h) was comparable between all interventions. The nitrogen balance between the three proteins tested showed no statistical differences. CONCLUSIONS High digestibility of rapeseed protein was found in rats. In humans, this is the first intervention study showing rapeseed protein (both isolate and hydrolyzate) as having a high nutritional quality and can be considered to be as efficient as soy protein for a postprandial amino acid response. This trial was registered at ClinicalTrials.gov Identifier: NCT01481584.

The Formation of Short-Chain Fatty Acids Is Positively Associated with the Blood Lipid–Lowering Effect of Lupin Kernel Fiber in Moderately Hypercholesterolemic Adults

Lupin kernel fiber beneficially modifies blood lipids because of its bile acid-binding capacity. The aim of this study was to evaluate the preventive effects of a lupin kernel fiber preparation on cardiovascular diseases and to clarify possible mechanisms. In a randomized, double-blind, controlled crossover trial, 60 moderately hypercholesterolemic adults (plasma total cholesterol: >5.2 mmol/L) passed 3 intervention periods in different orders with a 2-wk washout phase between each. Participants consumed either a high-fiber diet containing 25-g/d lupin kernel fiber (LF) or citrus fiber (CF), or a low-fiber control diet (CD) for 4 wk each. Anthropometric, plasma, and fecal variables were assessed at baseline and after the interventions. Contrary to the CF period, total (9%) and LDL (12%) cholesterol as well as triacylglycerols (10%) were lower after the LF period when compared with the CD period [P ≤ 0.02, adjusted for baseline, age, gender, and body mass index (BMI)]. HDL cholesterol remained unchanged. Moreover, the LF period reduced high-sensitivity C-reactive protein (P = 0.02) and systolic blood pressure (P = 0.01) when compared with baseline. Bile acid binding could not be shown because the excretion of total bile acids remained constant after the high-fiber diets. However, the LF period resulted in an enhanced formation of the main short-chain fatty acids in comparison with the CD period. During the CF period, only acetate increased significantly. Both high-fiber diets led to higher satiety and modified nutritional behavior, resulting in significantly lower body weight, BMI, and waist circumference compared with the CD period. The blood lipid-lowering effects of LF are apparently not a result of bile acid binding. Rather, we hypothesize for the first time, to our knowledge, that the blood lipid-lowering effects of LF may be mainly attributed to the formation of short-chain fatty acids, specifically propionate and acetate. This trial was registered at clinicaltrials.gov as NCT01035086.

Iodine content in milk from German cows and in human milk: new monitoring study

Objective: Milk can provide more than 1/3 of the iodine content in hu- man diet. Moreover, iodine supply in cows milk in Germany has improved throughout the last decade. Since 1982, analyses of io- dine content of cows and human milk have been undertaken regularly in the State of Thuringia (East Germany). Data show in- creasing iodine concentration in milk over the past few years. Nonetheless, dietary sup- ply of iodine via milk needs to be continu- ously monitored. Material and methods: To investigate the latest trend of iodine content in milk over time, 135 samples of cows milk and 65 samples of human milk were ana- lyzed by ICP-MS after digestion with tetra- methyl-ammonium hydroxide. Samples of cows milk (conventionally and organically produced) were purchased from the same supermarkets in Thuringia in March and No- vember every year between 2007 and 2011. Human milk samples were obtained on a vol- untary basis from breast-feeding women in Thuringia during the same time period. Re- sults: Samples of cows milk from 2007 to 2011 showed a mean iodine concentration of 122.0 ± 36.8 µg/l. There was no significant change during these 5 years (p > 0.05). In the same period, iodine content of conven- tionally produced milk was on average 51 µg/l higher compared to organically pro- duced milk (p < 0.001). For all human milk samples, the mean iodine content was 170 ± 96 µg/l, with a range of 45.6 - 478.4 µg/l. In breast milk, not only were high variations present between samples of milk from the individual women, but iodine content also varied over lactation time. Conclusions: The current results demonstrate that in East Ger- many the average iodine content in cows milk has remained stable at an appropriate level during the last 5 years. Although io- dine concentrations in human milk likewise reveal relatively constant values on average, individual variations can be substantial.

Lupine Kernel Fiber: Metabolic Effects in Human Intervention Studies and Use as a Supplement in Wheat Bread

Publisher Summary In many developed countries, supplementation with dietary fiber (DF) is of particular importance because far too little DF is consumed, despite the increasing knowledge about its value. Besides well-known fibers such as cereal fibers and pectin, a fiber source that has received little attention but that should be considered in the future is lupine fiber. Like soy, peas, and beans, lupines belong to the family Fabacea, commonly known as legumes. Due to its neutral taste, mouthfeel, and white color, lupine kernel fiber can be incorporated in high amounts into foods without impairing the sensory profile. This can be obtained by extracting proteins and other water-soluble substances from the dehulled and deoiled kernels. Lupine kernel fiber has a beneficial impact on the function of the colon and on general health. Lupine kernel fiber has a positive impact on the putative risk factors of colon cancer. Lupine kernel fiber addition results in increased water absorption of the dough. Due to the prolonged freshness, consumers preferred bread fortified with lupine kernel fiber at an optimum 10% level. Lupine kernel fiber can be used as a substitute for wheat, resulting in reduced carbohydrate content and caloric density.

Skin prick test reactivity to lupin in comparison to peanut, pea, and soybean in atopic and non-atopic German subjects: A preliminary cross-sectional study.

The increasing use of lupin in food processing poses a problem of potential (cross‐)allergic reactions. To evaluate the prevalence of sensitization to lupin in comparison to that of other legumes skin prick tests were performed with lupin, pea, peanut, and soybean in atopic (n = 81) and non‐atopic (n = 102) German adults. Of these 183 subjects, 20 subjects had to be excluded due to invalid skin prick tests (reaction to histamine <3 mm or to sodium chloride >2 mm). Thus, skin prick tests of 163 subjects were included in final analyses. Of 163 subjects, 18 had a positive reaction to at least one legume tested. Overall skin prick test reactivity was different among non‐atopic and atopic subjects (P = 0.005). Altogether, six subjects (4%) were sensitized to lupin, 12 (7%) to pea, 5 (3%) to peanut, and 8 (5%) to soybean. Two (2%) of the 92 non‐atopic subjects and 4 (6%) of the 71 atopic subjects had a positive skin prick test to lupin. Of the 6 subjects sensitized to lupin, 3 (50%) were also sensitized to pea, 3 (50%) to peanut, and 5 (83%) to soybean. In conclusion, the prevalence rates of lupin sensitization were comparable to or even lower than those of pea, peanut, and soybean. To date, lupin allergy is suspected to be relatively uncommon in the overall German population since lupin sensitization occurred in only 2% of non‐atopic subjects. However, there is a clear risk of a lupin allergy in predisposed subjects, since the frequency of lupin sensitization was 6% in atopic subjects. In particular, subjects with existing sensitization or allergy to other legumes are at higher risk for a sensitization or allergy to lupin due to cross‐reactivity.

Erratum to ‘Effects of polydextrose supplementation on different faecal parameters in healthy volunteers’ [Int J Food Sci Nutr (2008) 23:1–10]

The authors regret that the above published paper contains an error. The probe LAB 158 was used to detect the cell counts of total lactic acid bacteria and BIF 164 to detect the cell counts of total bifidobacteria. But in the article ‘L. acidophilus’ and ‘B. lactis’ have been mentioned incorrectly instead of ‘lactic acid bacteria’ and ‘bifidobacteria’. Hence, every ‘L. acidophilus’ has to be replaced by ‘lactic acid bacteria’ and every ‘B. lactis’ by ‘bifidobacteria’. The correct version of the abstract is shown below: