Preference and perception of fat in salty and sweet foods
Bolhuis, Dieuwerke P. ; Costanzo, Andrew ; Keast, Russell S.J. - \ 2018
Food Quality and Preference 64 (2018). - ISSN 0950-3293 - p. 131 - 137.
Fat - Preference - Salt - Saltiness - Sugar - Sweetness - Taste
Introduction Higher liking for fat is a risk factor for obesity. Fat in food is often combined with a sweet or salty taste. This study aims to investigate the role of fat on pleasantness and perception in both a salty and a sweet liquid food product. Methods In a complete factorial design, 47 participants (23 males) tasted creamy tomato soup and custard in four fat concentrations (0, 7.5, 15, 30%), combined with four salt concentrations (0.04, 0.35, 0.7, 1.5%) in soup, and four sugar concentrations (0.56, 4.5, 9, 18%) in custard. Participants rated pleasantness, saltiness intensity, sweetness intensity and fattiness intensity. The preferred fat concentrations were determined by hedonic ranking. Results Fat and salt separately affected pleasantness in soup (P <.01). Fat, sugar and their interaction affected pleasantness in custard (P <.001). Sugar and salt were a stronger influencer of pleasantness than fat. Preference for fat in soup was variable, whereas the highest concentration of 30% fat was preferred in custard (P <.001). Ratings of fattiness intensity were more responsive to fat concentrations in soup than in custard (P-interaction fat × food base <.001). Conclusion Salt and sugar are stronger influencers on food liking than fat. Across foods, there is no consistent effect of fat on perception or on liking, therefore the attractiveness of fat in foods cannot be generalised. The attraction to high fat levels in custard, while hardly perceiving differences in fat concentrations, remains unclear and needs further investigation.
Effect of dietary fat intake and genetics on fat taste sensitivity : A co-twin randomized controlled trial
Costanzo, Andrew ; Nowson, Caryl ; Orellana, Liliana ; Bolhuis, Dieuwerke ; Duesing, Konsta ; Keast, Russell - \ 2018
American Journal of Clinical Nutrition 107 (2018)5. - ISSN 0002-9165 - p. 683 - 694.
co-Twin - fat intake - fat taste - heritability - randomized controlled trial - weight - zygosity
Background Individuals with impaired fat taste (FT) sensitivity have reduced satiety responses after consuming fatty foods, leading to increased dietary fat intake. Habitual consumption of dietary fat may modulate sensitivity to FT, with high consumption decreasing sensitivity [increasing fatty acid taste threshold (FATT)] and low consumption increasing sensitivity (decreasing FATT). However, some individuals may be less susceptible to diet-mediated changes in FATT due to variations in gene expression. Objective The objective of this study was to determine the effect of an 8-wk low-fat or high-fat diet on FATT while maintaining baseline weight (<2.0 kg variation) to assess heritability and to explore the effect of genetics on diet-mediated changes in FATT. Design A co-Twin randomized controlled trial including 44 pairs (mean ± SD age: 43.7 ± 15.4 y; 34 monozygotic, 10 dizygotic; 33 women, 10 men, 1 gender-discordant) was conducted. Twins within a pair were randomly allocated to an 8-wk low-fat (<20% of energy from fat) or high-fat (>35% of energy from fat) diet. FATT was assessed by a 3-Alternate forced choice methodology and transformed to an ordinal scale (FT rank) at baseline and at 4 and 8 wk. Linear mixed models were fit to assess diet effect on FT rank and diet effect modification due to zygosity. A variance components model was fit to calculate baseline heritability. Results There was a significant time × diet interaction for FT rank after the 8-wk trial (P < 0.001), with the same conclusions for the subset of participants maintaining baseline weight (low-fat; n = 32; high-fat: n = 35). There was no evidence of zygosity effect modification (interaction of time × diet × zygosity: P = 0.892). Heritability of baseline FT rank was 8%. Conclusions There appears to be little to no genetic contribution on heritability of FATT or diet-mediated changes to FATT. Rather, environment, specifically dietary fat intake, is the main influencer of FT sensitivity, regardless of body weight. This trial was registered with the Australian New Zealand Clinical Trials Registry at http://www.anzctr.org.au/ as ACTRN12613000466741.
Salt promotes passive overconsumption of dietary fat in humans
Bolhuis, Dieuwerke P. ; Costanzo, Andrew ; Newman, Lisa P. ; Keast, Russell S.J. - \ 2016
The Journal of Nutrition 146 (2016)4. - ISSN 0022-3166 - p. 838 - 845.
Ad libitum food intake - Fat - Fat taste sensitivity - Salt - Satiation
Background: Excess fat consumption has been linked to the development of obesity. Fat and salt are a common and appetitive combination in food; however, the effect of either on food intake is unclear. Fat taste sensitivity has been negatively associated with dietary fat intake, but how fat taste sensitivity influences the intake of fat within a meal has, to our knowledge, not yet been investigated. Objectives: Our objectives were, first, to investigate the effects of both fat and salt on ad libitum food intake and, second, to investigate the effects of fat taste sensitivity on satiation responses to fat and whether this was affected by salt. Methods: Forty-eight healthy adults [16men and 32women, aged 18-54 y, bodymass index (kg/m2): 17.8-34.4] were recruited and their fat taste sensitivity was measured by determination of the detection threshold of oleic acid (18:1n-6). In a randomized 2 × 2 crossover design, participants attended 4 lunchtime sessions after a standardized breakfast. Meals consisted of elbow macaroni (56%)with sauce (44%); sauces weremanipulated to be 1) low-fat (0.02% fat, wt:wt)/low-salt (0.06% NaCl,wt:wt), 2) low-fat/high-salt (0.5% NaCl, wt:wt), 3) high-fat (34% fat, wt:/wt)/low-salt, or 4) high-fat/high-salt. Ad libitum intake (primary outcome) and eating rate, pleasantness, and subjective ratings of hunger and fullness (secondary outcomes) were measured. Results: Salt increased food and energy intakes by 11%, independent of fat concentration (P = 0.022). There was no effect of fat on food intake (P = 0.6), but high-fat meals increased energy intake by 60% (P < 0.001). A sex × fat interaction was found (P = 0.006), with women consuming 15% less by weight of the high-fat meals than the low-fat meals. Fat taste sensitivity was negatively associated with the intake of high-fat meals but only in the presence of low salt (fat taste × salt interaction on delta intake of high-fat 2 low-fat meals; P = 0.012). Conclusions: The results suggest that salt promotes passive overconsumption of energy in adults and that salt may override fat-mediated satiation in individuals who are sensitive to the taste of fat.
Genome sequence and analysis of the Irish potato famine pathogen Phytophthora infestans
Haas, B.J. ; Kamoun, S. ; Zody, M.C. ; Jiang, R.H.Y. ; Handsaker, R.E. ; Cano, L.M. ; Grabherr, M. ; Kodira, C.D. ; Raffaele, S. ; Torto-Alalibo, T. ; Bozkurt, T.O. ; Ah-Fong, A.M.V. ; Alvarado, L. ; Anderson, V.L. ; Armstrong, M.R. ; Avrova, A. ; Baxter, L. ; Beynon, J. ; Boevink, P.C. ; Bollmann, S.R. ; Bos, J.I.B. ; Bulone, V. ; Cai, G. ; Cakir, C. ; Carrington, J.C. ; Chawner, M. ; Conti, L. ; Costanzo, S. ; Ewan, R. ; Fahlgren, N. ; Fischbach, M.A. ; Fugelstad, J. ; Gilroy, E.M. ; Gnerre, S. ; Green, P.J. ; Grenville-Briggs, L.J. ; Griffith, J. ; Grunwald, N.J. ; Horn, K. ; Horner, N.R. ; Hu, C.H. ; Huitema, E. ; Jeong, D.H. ; Jones, A.M.E. ; Jones, J.D.G. ; Jones, R.W. ; Karlsson, E.K. ; Kunjeti, S.G. ; Lamour, K. ; Liu, Z. ; Ma, L. ; Maclean, D. ; Chibucos, M.C. ; McDonald, H. ; McWalters, J. ; Meijer, H.J.G. ; Morgan, W. ; Morris, P.F. ; Munro, C.A. ; O'Neill, K. ; Ospina-Giraldo, M. ; Pinzon, A. ; Pritchard, L. ; Ramsahoye, B. ; Ren, Q. ; Restrepo, S. ; Roy, S. ; Sadanandom, A. ; Savidor, A. ; Schornack, S. ; Schwartz, D.C. ; Schumann, U.D. ; Schwessinger, B. ; Seyer, L. ; Sharpe, T. ; Silvar, C. ; Song, J. ; Studholme, D.J. ; Sykes, S. ; Thines, M. ; Vondervoort, P.J.I. van de; Phuntumart, V. ; Wawra, S. ; Weide, R. ; Win, J. ; Young, C. ; Zhou, S. ; Fry, W. ; Meyers, B.C. ; West, P. van; Ristaino, J. ; Govers, F. ; Birch, P.R.J. ; Whisson, S.C. ; Judelson, H.S. ; Nusbaum, C. - \ 2009
Nature 461 (2009). - ISSN 0028-0836 - p. 393 - 398.
effector proteins - rxlr effectors - cell-death - plant - avirulence - avr3a - resistance - infection - genes
Phytophthora infestans is the most destructive pathogen of potato and a model organism for the oomycetes, a distinct lineage of fungus-like eukaryotes that are related to organisms such as brown algae and diatoms. As the agent of the Irish potato famine in the mid-nineteenth century, P. infestans has had a tremendous effect on human history, resulting in famine and population displacement(1). To this day, it affects world agriculture by causing the most destructive disease of potato, the fourth largest food crop and a critical alternative to the major cereal crops for feeding the world's population(1). Current annual worldwide potato crop losses due to late blight are conservatively estimated at $6.7 billion(2). Management of this devastating pathogen is challenged by its remarkable speed of adaptation to control strategies such as genetically resistant cultivars(3,4). Here we report the sequence of the P. infestans genome, which at similar to 240 megabases (Mb) is by far the largest and most complex genome sequenced so far in the chromalveolates. Its expansion results from a proliferation of repetitive DNA accounting for similar to 74% of the genome. Comparison with two other Phytophthora genomes showed rapid turnover and extensive expansion of specific families of secreted disease effector proteins, including many genes that are induced during infection or are predicted to have activities that alter host physiology. These fast-evolving effector genes are localized to highly dynamic and expanded regions of the P. infestans genome. This probably plays a crucial part in the rapid adaptability of the pathogen to host plants and underpins its evolutionary potential.