Bryophytes are abundant in streams and are a habitat for many invertebrates, but their contribution to the diet of fluvial zoobenthos is still debated. To estimate the amount of bryophyte-derived organic matter assimilated by benthic invertebrates, we used a combination of fatty acid and stable isotope analyses during a four-year monthly study of a littoral site in the Yenisei River (Siberia, Russia). Acetylenic acids, which are highly specific biomarkers of the water moss Fontinalis antipyretica, were found in lipids of all dominant benthic animals: gammarids, ephemeropterans, chironomids and trichopterans. The dominant zoobenthic species, Eulimnogammarus viridis, had maximum levels of the biomarkers in its biomass during winter, and minimum levels in summer. The zoobenthos in the studied site regularly consume and assimilate bryophyte-derived organic matter as a minor supplemental food. This consumption increases in winter, when the main food source of the zoobenthos, epilithic biofilms, are probably scarce.

In the present study, production and using possibilities of powder of macaroni boiling water (PMBW) were investigated. After cooking process of macaroni, firstly pre-drying was carried out at 50 °C in a drying oven and then lyophilization process was conducted to obtain final powder product. Physicochemical characterizations like total dry matter, ash, fat, protein, pH, aw and color properties were carried out and also technological properties of sample were determined. Both macaroni boiling water and the final powder product were examined in terms of microbiological analyses. It was found that macaroni boiling water had to be processed in 6 h after cooking if the cooking water was stored at room temperature. Also, the duration of 12 h after cooking was found to be limit level for microbiological safety of cooking water if it was stored at +4 °C. Besides, scanning electron micrographs of particles and fatty acid and mineral profile of the final powder product were determined. Macaroni boiling water is a by-product having a lot of nutrients and in this study it was proved that utilization of this by-product may be feasible. The macaroni boiling water can be used as a food ingredient and also as an enrichment agent.

The purpose of this study was to investigate the difference in expression of fatty acid biosynthesis genes and survival of different serotypes of Salmonella when incubated in a low‐water‐activity (aw) food over a 14‐day period. Stationary cells of five strains of Salmonella enterica belonging to 3 different serovars (Typhimurium ATCC 2486, Enteritidis H4267, Tennessee ARI‐33, Tennessee S13952 and Tennessee K4643) were inoculated into granular sugar (aW = 0·50) and held aerobically over a 14‐day period at 25°C. Survival was determined by enumerating colonies on TSA and XLT‐4 plates at 0, 1, 3, 5, 7 and 14 days. Correspondingly, gene expression was evaluated for three selected genes involved in fatty acid biosynthesis and modification (fabA, fabD and cfa). After 14 days of incubation, the population was reduced from 2·29 to 3·36 log for all five strains. Salmonella Tennessee ARI‐33 and Salm. Tennessee K4643 displayed greater survival than Salm. Typhimurium and Salm. Enteritidis. The increased expression of the cfa gene (involved in cyclopropane fatty acid biosynthesis) over 14 days was found associated with strains with a lower survival rate. The fabA gene (involved in unsaturated fatty acid biosynthesis) was observed up‐regulated for all strains for at least one sampling time and for Salm. Tennessee ARI‐33 for all time points tested, suggesting its potential role in enhancing Salmonella survival in low awfoods. SIGNIFICANCE AND IMPACT OF THE STUDY: Numerous outbreaks of salmonellosis associated with low‐water‐activity foods have been reported. Therefore, the adaptive mechanisms utilized by Salmonella to survive in low‐water‐activity foods for prolonged periods of time need to be better understood. The results in this study showed that low‐water‐activity environments increase expression of gene fabA, which is involved in unsaturated fatty acid biosynthesis of Salmonella, while the increased expression of cfa, associated with cyclopropane fatty acid synthesis, was associated with decreased survival over 14 days.

Eight multicannulated heifers (average BW 415 +/- 34 kg) were used in a replicated 4 X 4 Latin square to evaluate fluid milk processing wash water solids (WWS) as a dietary N source. Heifers were fed corn/cottonseed hull-based diets containing soybean meal (control, 0% WWS N) or WWS replacing soybean meal at 33, 67, or 100% of supplemental dietary N. Total tract and ruminal DM and OM digestibilities decreased linearly or cubically (P < .05) as dietary WWS N increased. Total ruminal VFA concentration (P < .05) and propionic acid molar proportion (P < .10) were greater in heifers fed 0 vs 100% WWS N. Heifers fed 0% WWS N had the greatest (P < .05) ruminal ammonia concentration at all sampling times. Dietary WWS did not affect (P > .10) ruminal pH, fluid dilution rate, fluid flow, fluid volume, or turnover time. Total tract N digestibility decreased quadratically (P < .10) with increasing WWS N in the diet. Supplemental WWS N did not affect (P > .10) flow of duodenal ammonia N or bacterial N, or efficiency of microbial N synthesis. Diets containing WWS N resulted in a cubic increase (P < .10) in duodenal flow of essential amino acids compared with 0% WWS N; however, there were no differences in small intestinal amino acid disappearance. Data indicate that WWS can replace 33% of the soybean meal N in a corn/cottonseed hull-based diet without decreasing ruminal fermentation, fluid digesta kinetics, microbial efficiency, or small intestinal amino acid utilization.

BACKGROUND: Partition coefficients give an indication of the retention of aroma compounds by the food matrix. Data in the literature are obtained by various methods, under various conditions and expressed in various units, and it is thus difficult to compare the results. The aim of the present study was first to obtain gas/water and gas/matrix partition coefficients of selected aroma compounds, at different temperatures, in order to calculate thermodynamic parameters and second to compare the retention of these aroma compounds in different food matrices.RESULTS: Yogurts containing lipids and proteins induced a higher retention of aroma compounds than model gel matrices. The observed effects strongly depend on hydrophobicity of aroma compounds showing a retention for ethyl hexanoate and a salting out effect for ethyl acetate. A small but noticeable decrease in enthalpy of affinity is observed for ethyl butyrate and ethyl hexanoate between water and food matrices, suggesting that the energy needed for the volatilization is lower in matrices than in water.CONCLUSION: The composition and complexity of a food matrix influence gas/matrix partition coefficients or aroma compounds in function of their hydrophobicity and to a lower extent enthalpy of vaporization.

Failing to initiate first feeding during the transition from endogenous nutrition to exogenous feeding will lead to starvation of fish larvae. However, little is known about the mechanism of first feeding selection of fish. Golden mandarin fish larvae (3 d after hatch, 2.05 ± 0.03 mg) were fed with four different foods for 7 d, including the following: M – Megalobrama amblycephala (prey fish larvae as natural food); S – surimi of M. amblycephala; A – Artemia (zooplankton); and MA –mixed M. amblycephala with Artemia (mixed food). Larvae fed with the mixed food achieved an appropriate balance between high survival and good growth through elevating the expression of growth genes (GH, IGF‐I, and IGF‐II) and fatty acid synthesis genes (FAD and ELO). Growth performance of fish fed with MA reared at different salinities (0, 5, and 10 ppt) was examined. The salinity of 5 ppt produced the best growth performance of the three salinity levels tested. Fish larvae adapted to high‐ or low‐salinity environments through increasing the expression of lipolysis genes (HSL, LPL, and HL). Therefore, both food type and salinity affect the growth, survival, and lipometabolism of golden mandarin fish larvae during initial feeding stage, and mixed food and 5 ppt salinity improved its survival and growth.

Twelve ruminally, duodenally, and ileally cannulated (average initial BW 313 +/- 20 kg) and 27 intact Hereford heifers (average initial BW 256 +/- 17 kg) were used in two experiments to evaluate dairy food wash water solids (WWS) as a protein source in medium-quality hay diets. Heifers received a basal diet of orchardgrass hay (7.4% CP) and were assigned to one of three supplement treatments: control (C;.9% CP), WWS (18.8% CP)-, and soybean meal (SBM 19.1% Cp)-based supplements (fed at 1.5 kg of DM/d). Supplements were formulated to have similar ME concentrations. Ruminal ammonia concentrations were greater (P <.10) for WWS- and SBM-supplemented heifers than for C heifers at most sampling times. Moreover, WWS and SBM increased (P < .10) total VFA (mM) and acetate (mol/100 mol) and lowered propionate (mol/100 mol) at several sampling times. Ruminal fluid volume (liters) was unchanged (P > .10) by treatment; however, fluid dilution and flow rate (liters/h) were less (P < .10) in C heifers than in heifers fed SBM or WWS supplements. Wash water solids and SBM supplementation increased (P < .10) OM, NDF, and ADF digestibilities compared with C heifers. Feeding WWS and SBM supplements increased BW at 84 d (P < .10) compared with C-supplemented heifers. Forage intake at 54 and 84 d by heifers supplemented with SBM or WWS was greater (P < .10) than by C heifers. Control-supplemented heifers had the least, WWS intermediate, and SBM the greatest ADG at 84 d (P < .10; .14 vs .35 vs .48 kg/d, respectively). These data indicate that WWS may be used as a protein source without serious adverse effects in heifers consuming medium-quality hay for 84 d.