Ontogenetic and temporal variability in the fat content and fatty acid composition of Atlantic herring (Clupea harengus) from the Bay of Fundy, Canada

Atlantic herring (Clupea harengus) is an ecologically and economically valuable species in many food webs, yet surprisingly little is known about the variation in the nutritional quality of these fish. Atlantic herring collected from 2005 through 2008 from the Bay of Fundy, Canada, were examined for variability in their nutritional quality by using total lipid content (n=889) and fatty acid composition (n=551) as proxies for nutritional value. A significant positive relationship was found between fish length and total lipid content. Atlantic herring also had significantly different fatty acid signatures by age. Fish from 2005 had significantly lower total lipid content than fish from 2006 through 2008, and all years had significantly different fatty acid signatures. Summer fish were significantly fatter than winter fish and had significantly different fatty acid signatures. For all comparisons (ontogenetic, annual, and seasonal) percent concentrations of omega-3, -6, and long-chain monounsaturated fatty acids were the most important for distinguishing between the fatty acid signatures of fish. This study underscores the importance of quantifying variation in prey quality synoptically with prey quantity in food webs over ontogenetic and temporal scales when evaluating the effect of prey nutritional quality on predators and on modeling trophic dynamics.

Influence of fat content on the quality and shelf life of cured sardines

The paper presents results of studies on the effect of seasonal variations in the fat content on the quality and shelf life of dry cured, pickle cured and smoke cured oil sardines. The merits and defects of each method of curing during different seasons are discussed.

Circulating pancreatic polypeptide concentrations predict visceral and liver fat content

CONTEXT AND OBJECTIVE: No current biomarker can reliably predict visceral and liver fat content, both of which are risk factors for cardiovascular disease. Vagal tone has been suggested to influence regional fat deposition. Pancreatic polypeptide (PP) is secreted from the endocrine pancreas under vagal control. We investigated the utility of PP in predicting visceral and liver fat. PATIENTS AND METHODS: Fasting plasma PP concentrations were measured in 104 overweight and obese subjects (46 men and 58 women). In the same subjects, total and regional adipose tissue, including total visceral adipose tissue (VAT) and total subcutaneous adipose tissue (TSAT), were measured using whole-body magnetic resonance imaging. Intrahepatocellular lipid content (IHCL) was quantified by proton magnetic resonance spectroscopy. RESULTS: Fasting plasma PP concentrations positively and significantly correlated with both VAT (r = 0.57, P < .001) and IHCL (r = 0.51, P < .001), but not with TSAT (r = 0.02, P = .88). Fasting PP concentrations independently predicted VAT after controlling for age and sex. Fasting PP concentrations independently predicted IHCL after controlling for age, sex, body mass index (BMI), waist-to-hip ratio, homeostatic model assessment 2-insulin resistance, (HOMA2-IR) and serum concentrations of triglyceride (TG), total cholesterol (TC), and alanine aminotransferase (ALT). Fasting PP concentrations were associated with serum ALT, TG, TC, low- and high-density lipoprotein cholesterol, and blood pressure (P < .05). These associations were mediated by IHCL and/or VAT. Fasting PP and HOMA2-IR were independently significantly associated with hepatic steatosis (P < .01). CONCLUSIONS: Pancreatic polypeptide is a novel predictor of visceral and liver fat content, and thus a potential biomarker for cardiovascular risk stratification and targeted treatment of patients with ectopic fat deposition.

Performance of palm- based fat blends with a low saturated fat content in puff pastry

Four fat blends based on palm fractions in combination with high oleic sunflower oil (HOSF) with a relatively low saturated fatty acid content (29.2±0.85%, i.e. less than 50% of that of butter) were prepared. The saturated fat was located in different triacylglycerols (TAG) structures in each blend. Principal saturated TAG were derived from palm stearin (POs, containing tripalmitoyl glycerol - PPP), palm mid fraction (PMF, containing 1,3-dipalmitoyl-2-oleoyl glycerol - POP) and interesterified PMF (inPMF, containing PPP, POP and rac-1,2-dipalmitoyl-3-oleoyl glycerol - PPO). Thus, in blend 1, composed of POs and HOSF, the saturates resided principally in PPP. In blend 2, composed of POs, PMF and HOSF, the principal saturate-containing TAG were PPP and POP. Blend 3, composed of inPMF and HOSF, was similar to blend 2 except that the disaturated TAG comprised a 2:1 mixture of PPO:POP. Finally, blend 4, a mixture of PMF and HOSF, had saturates present mainly as POP. The physical properties and the functionality of blends, as shortenings for puff pastry laminated in a warm bakery environment (20-30°C), were compared with each other, and with butter. Puff pastry prepared with blend 1 (POs:HOSF 29:71) and blend 4 (PMF:HOSF 41:59), was very hard; blend 2 (POs:PMF:HOSF 13:19:68) was most similar to butter in the compressibility of the baked product and it performed well in an independent baking trial; blend 3 (inPMF:HOSF 40:60) gave a product that required a higher force for compression than butter.

Calpain 3 gene expression in skeletal muscle is associated with body fat content and measures of insulin resistance

OBJECTIVE: To investigate whether skeletal muscle gene expression of calpain 3 is related to obesity and insulin resistance.

DESIGN: Cross-sectional studies in 27 non-diabetic human subjects and in Psammomys obesus, a polygenic animal model of obesity and type 2 diabetes.

MEASUREMENTS: Expression of CAPN3 in skeletal muscle was measured using Taqman fluorogenic PCR. In the human subjects, body composition was assessed by DEXA and insulin sensitivity was measured by euglycemic-hyperinsulinemic clamp. In Psammomys obesus, body composition was determined by carcass analysis, and substrate oxidation rates, physical activity and energy expenditure were measured by whole-body indirect calorimetry.

RESULTS: In human subjects, calpain 3 gene expression was negatively correlated with total (P=0.022) and central abdominal fat mass (P=0.034), and with blood glucose concentration in non-obese subjects (P=0.017). In Psammomys obesus, calpain 3 gene expression was negatively correlated with circulating glucose (P=0.013) and insulin (P=0.034), and with body fat mass (P=0.049). Indirect calorimetry revealed associations between calpain 3 gene expression and carbohydrate oxidation (P=0.009) and energy expenditure (P=0.013).

CONCLUSION/INTERPRETATION: Lower levels of expression of calpain 3 in skeletal muscle were associated with reduced carbohydrate oxidation and elevated circulating glucose and insulin concentrations, and also with increased body fat and in particular abdominal fat. Therefore, reduced expression of calpain 3 in both humans and Psammomys obesus was associated with phenotypes related to obesity and insulin resistance.

Two important exceptions to the relationship between energy density and fat content: food with reduced-fat claims and high-fat vegetable-based dishes

Objective: To test the hypothesis that many foods with reduced-fat (RF) claims are relatively energy-dense and that high-fat (HF) vegetable-based dishes are relatively energy-dilute.

Design: Nutrient data were collected from available foods in Melbourne supermarkets that had an RF claim and a full-fat (FF) equivalent. Nutrient analyses were also conducted on recipes for HF vegetable-based dishes that had more than 30% energy from fat but less than 10% from saturated fat. The dietary intake data (beverages removed) from the 1995 National Nutrition Survey were used for the reference relationships between energy density (ED) and percentage energy as fat and carbohydrate and percentage of water by weight.

Statistics: Linear regression modelled relationships of macronutrients and ED. Paired t-tests compared observed and predicted reductions in the ED of RF foods compared with FF equivalents.

Results: Both FF and RF foods were more energy-dense than the Australian diet and the HF vegetable-based dishes were less energy-dense. The Australian diet showed significant relationships with ED, which were positive for percentage energy as fat and negative for percentage energy as carbohydrate. There were no such relationships for the products with RF claims or for the HF vegetable-based dishes.

Conclusion: While, overall, a reduced-fat diet is relatively energy-dilute and is likely to protect against weight gain, there appear to be two important exceptions. A high intake of products with RF claims could lead to a relatively energy-dense diet and thus promote weight gain. Alternatively, a high intake of vegetable-based foods, even with substantial added fat, could reduce ED and protect against weight gain.

Fat content of chips, quality of frying fat and deep-frying practices in New Zealand fast food outlets

Objectives: To collect baseline data on the fat content of hot chips, quality (degradation) of cooking fat, deep-frying practices and related attitudes in fast food outlets in New Zealand. To identify the key determinants of the fat content of chips and quality of cooking fat. Methods: A nationally representative sample of fast food outlets (n=150, response rate 80%) was surveyed between September 1998 and March 1999. Data collected included a questionnaire, observation of cooking practices and analysis of cooked chips and frying fat. Results: Only 8% of independent operators had formal training in deep frying practices compared with 93% of chain operators. There was a wide range of fat content of chips (5%-20%, mean 11.5%). The use of thinner chips, crinkle cut chips and lower fryer fat temperature were associated with higher chip fat content. Eighty-nine per cent of chain outlets used 6–10 mm chips compared with 83% of independent outlets that used chips ≥12 mm. A wide range of frying temperatures was recorded (136–233°C) with 58% of outlets frying outside the reference range (175–190°C). As indices of fat degradation, fat acid and polar compound values above the recommended levels occurred in 54% and 5% of outlets respectively. Operators seemed willing to learn more about best practice techniques, with lack of knowledge being the main barrier to change. Conclusions and implications: Deep frying practices could be improved through operator training and certification options. Even a small decrease in the mean fat content of chips would reduce the obesogenic impact of this popular food.

Growth, fat content and fatty acid profile of South American catfish, surubim (Pseudoplatystoma fasciatum) juveniles fed live, commercial and formulated diets

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Association of dyslipidemia with intakes of fruit and vegetables and the body fat content of adults clinically selected for a lifestyle modification program

To investigate the relationship of dyslipidemia with demographic distribution and patterns of body fat and dietary intakes. From a universe of adults clinically selected for a lifestyle modification program 979 subjects (409 males and 570 females, 52.2 +/- 9.6 years) fulfilled the inclusion criteria. Overnight-fasting plasma was assayed (dry chemistry) for triglycerides (TG), total (TC) and HDL fraction of cholesterol given the non-HDL (n-HDL) fraction by the difference. Anthropometric assessment included body weight (kg), height (m), fat (bioelectrical impedance) and waist circumference (WC). Food intake was assessed by the 24-hour recall questionnaire and the food groups evaluated through recommendations from an adapted food pyramid. The chances of dyslipidemia from other variable changes were determined by logistic regression with p < 0.05. Normal values of BMI and WC were protective against all dyslipidemia markers whereas only hypercholesterolemia was influenced by diet (meat intake > 2 servings). Dietary intakes have protective effects against hypertriglyceridemia with whole grains, odds ratio (OR) 0.342 (Cl 95%, 0.154-0.760), fruits >= 3 servings (OR 0.523, 0.290-0.941) and vegetables >= 4 servings (OR 0.360, 0.176-0.735). In general total body and abdominal adiposity influenced all dystipidemia markers while dietary intake of fruits and vegetables protected against triglyceridemia.

FLOW PROPERTIES and TUBE FRICTION FACTOR of MILK CREAM: INFLUENCE of TEMPERATURE and FAT CONTENT

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)