Determination of Principal Components for Characterizing the Drying of Sea Cucumbers (Stichopus japonicus Selenka) Using Far Infrared Radiation Drying and Hot Air Drying

Principal component analysis (PCA) and multiple linear regression (MLR) were conducted to characterize the drying of sea cucumber (SC). Far infrared radiation drying (FIRD) and hot air drying (AD) were used to dehydrate SC. Thirteen variables—including the morphological, color, and textural properties of dried SC—were selected for statistical analysis. The analysis of these 13 variables yielded three principal components showing significant correlations. PCA showed that the first three components represented 86.2% of the total variation. The first principal component was primarily related to the morphological properties of SC. The principal components determined by the PCA were more strongly influenced by the morphological variables than by the drying method. Of the morphological variables, the weight of SC had the strongest influence on the drying time and rehydration ratio of FIRD and AD.     

Free Lipids in Air‐Classified High‐Protein Fractions of Hard Winter Wheat Flours and Their Effects on Breadmaking Quality

Free lipids (FL) were extracted from straight‐grade flours (SF) and the air‐classified high‐protein fractions (ACHPF) of nine hard winter wheats. The mean values of FL contents in 10 g (db) SF and ACHPF were, respectively, 92.8 and 178.5 mg for total FL, 74.1 and 141.9 mg for nonpolar lipids (NL), 12.8 and 20.9 mg for glycolipids (GL), and 4.9 and 12.0 mg for phospholipids (PL). FL compositions of SF and ACHPF showed nonsignificant differences in NL (80.7 and 81.1% of the FL) but significant differences in GL (13.9 and 12.0% of the FL) and PL (5.4 and 6.9% of the FL). Fortification of SF with ACHPF by blending to reach 13% protein content increased gluten quantity and thereby loaf volume but decreased gluten index, loaf volume regression, and crumb grain scores. NL contents showed significant relationships with dry gluten contents (r = 0.79) and gluten index (r = ‐0.83) values, indicating that high NL content in ACHPF could decrease gluten quality of fortified flours. Thus, an optimum balance should be maintained during fortification.     

Influence of Annealing on Gel Properties of Mung Bean Starch

Mung bean starch gels (8% solids) were prepared after annealing at 45–60°C for 1–24 hr, and the relationship between the physical properties of gels and the swelling power (SP) and solubility of starch was investigated. The SP and solubility decreased with increasing annealing temperature and time, mostly in the first 6 hr. The solubles were mainly composed of amylose. Gel hardness at a 5 mm depth of annealed starch was larger than that of native starch, and gel hardness increased as SP decreased (r = ‐0.94). Upon continued compression, the yield force of gel showed a different function. Above SP of ≈12.5, the yield force of annealed starch gels decreased, but at <12.5 the yield force increased with increasing SP. Both granular rigidity and extent of packing appeared to determine the yield force. Although annealing increased the gel hardness, α‐amylase digestibility of gel was not affected. Pasting analysis in the Rapid Visco Analyser (RVA) revealed that annealing increased pasting temperature. A pasting peak was found only in 45 and 50°C annealed starches. Overall paste viscosities of the starches annealed at >55°C were lower than that of the control starch. Final viscosities in RVA were correlated with the yield force of gel (r = 0.99).     

Volatiles in Selected Commercial Breads

Selected types of commercial breads obtained from local markets, including white sandwich, Irish oatmeal, soft rye, hearty rye, sour dough, home-like white, and onion-basil, were analyzed for volatiles. Using a purge and trap instrument, volatiles were purged directly from fresh crumb and crust samples of each bread type, collected on a trap (Tenax-TA), and transferred to a gas chromatograph. Separated components were detected and identified using mass and infrared spectroscopic detectors. Many components were present in all of the bread samples, with relative amounts varying among bread types and crust and crumb samples of a given bread type. Alcohols were generally the most abundant, followed in approximate order by aldehydes, esters, ketones, acids, various aromatics, terpenes, and hydrocarbons. Flavor additives, such as limonene, carvone, and other related compounds, were found mostly in rye and onion-basil breads. Composition of volatiles from sour dough bread differed greatly from the other breads, especially in increased levels of aldehydes, acids, and certain esters. Unsaturated aldehydes, such as 2-hexenal and 2-heptenal, were most abundant in sour dough bread.     

Effect of cross-linking agent structure on the shape memory property of polyurethane block copolymer

Effect of cross-linking agent on the shape memory and mechanical property of polyurethane (PU) block copolymer is comprehensively investigated. The selected chemical cross-linking agents are glycerol, 1,2,6-trihydroxyhexane, and 2,4,6-trihydroxybenzaldehyde that are differentiated from each other in having remote hydroxyl group and aromatic ring. Significant increase in maximum stress was observed for all of the cross-linked PUs, although the cross-linker structure was different. Structural change of PU after cross-linking as evidenced by differential scanning calorimetry and infrared spectra was not detected, suggesting that interaction between PU chains remained intact. Shape recovery went to as high as 95 % after cross-linking for all of the cross-linking agents, and shape retention did not improve even if cross-linker was used. The remarkable increase in shape recovery and maximum stress definitely originated from the employment of a cross-linking agent, and the effect of different cross-linker structure on shape memory and mechanical property is discussed.     

Encapsulation capacity of Artemia nauplii with customized probiotics for use in the cultivation of western king prawns (Penaeus latisulcatus Kishinouye, 1896)

The encapsulation capacity of Artemia nauplii with customized probiotics Pseudomonas synxantha and Pseudomonas aeruginosa for use in the cultivation of western king prawns (Penaeus latisulcatus) was investigated. Seven trials were conducted to investigate this encapsulation capacity in terms of Artemia survival and probiotic load in Artemia. Newly hatched Artemia nauplii at 250 nauplii mL^?1 were fed individual probiotics at 0, 10³, 10⁵ and 10⁷ colony‐forming units (CFU) per millilitre, and mixtures of these two probiotics (10⁵ CFU mL^?1) at 30:70, 50:50 or 70:30 v/v in a medium of ozonated water (OW), tryptone soya broth (TSB), and a mixture of these media. The appropriate medium for encapsulation of probiotics by Artemia nauplii was the mixture of OW and TSB at 75:25 v/v; whereas, the use of OW or TSB alone was not effective. Artemia nauplii most effectively encapsulated the customized probiotics at 10⁵ CFU mL^?1. The results indicates that the encapsulation of Artemia nauplii is optimized by using a combination of P. synxantha and P. aeruginosa at 50:50 v/v in a media mixture of OW and TSB at 75: 25 v/v. Artemia should be harvested at 48 h when survival is still high (78%) and the probiotic load in Artemia is high (3 × 10⁴ CFU nauplius^?1).     

Lipogenesis and stearoyl-CoA desaturase gene expression and enzyme activity in adipose tissue of short- and long-fed Angus and Wagyu steers fed corn- or hay-based diets

Angus and Wagyu steers consuming high-roughage diets exhibit large differences in adipose tissue fatty acid composition, but there are no differences in terminal measures of stearoyl-CoA desaturase (SCD) activity or gene expression. Also, adipose tissue lipids of cattle fed corn-based diets have greater MUFA:SFA ratios than cattle fed hay-based diets. We hypothesized that any changes in SCD gene expression and activity would precede similar changes in adipose tissue lipogenesis between short- and long-fed endpoints. Furthermore, changes in SCD activity and gene expression between production endpoints would differ between corn- and hay-fed steers and between Wagyu and Angus steers. Angus (n = 8) and Wagyu (n = 8) steers were fed a corn-based diet for 8 mo (short-fed; 16 mo of age) or 16 mo (long-fed; 24 mo of age), whereas another group of Angus (n = 8) and Wagyu (n = 8) steers was fed a hay-based diet for 12 mo (short-fed; 20 mo of age) or 20 mo (long-fed; 28 mo of age) to match the end point BW of the corn-fed steers. Acetate incorporation into lipids in vitro was greater (P < 0.01) in corn-fed steers than in hay-fed steers and tended (P = 0.06) to be greater in Wagyu than in Angus s.c. adipose tissue because the rate in Wagyu was twice that of Angus adipose tissue in the corn-fed, short-fed steers. There were diet x end point interactions for lipogenesis in i.m. and s.c. adipose tissues (both P < 0.01) because lipogenesis was 60 to 90% lower in the long-fed cattle than in short-fed cattle fed the corn-based diet. The greatest SCD enzyme activity in Angus s.c. adipose tissue was observed at 24 mo of age (corn-based diet), but activity in Wagyu adipose tissue was greatest at 28 mo of age (hay-based diet; breed x diet x end point interaction, P = 0.08). For short- vs. long-fed endpoints in Angus, s.c. adipose tissue SCD activity was less (hay diet) or the same (corn diet). Conversely, SCD gene expression was greatest in long-fed Wagyu steers fed the hay- or corn-based diets (breed x end point interaction; P < 0.01). Contrary to our hypotheses, SCD activity increased over time, whereas lipogenesis from acetate decreased. However, the developmental pattern of SCD gene expression and activity differed markedly between hay-fed Angus and Wagyu adipose tissues, which may explain the differences in the MUFA:SFA ratios observed in adipose tissues from these cattle.     

Assessment of household risk management strategies for coastal aquaculture: the case of clam farming in Thaibinh Province,Vietnam

Clam farmers have experienced different types of risks that have been further exacerbated by the rapid expansion of clam farming areas, increased growing densities, and increased market difficulties in recent years in the Thaibinh Province of Vietnam. Most farmers have been seriously affected by production risk, market risk, and financial risk, while a number of others have met with success in almost all of their clam-raising cycles. This study applied a differentiating comparative analysis method and multiple discriminant analysis method to discuss the differences in risk management strategies between and among clam farming households and the impacts of those differences on their success/failure rates. In general, the tactics are related to increase in farm size, the application of technical innovations, diversifying livelihood activities, and accessing secure financial sources all provided better conditions for clam growth, diminished losses, and led to speedier recovery from shocks. To support farmers in managing risks, several government interventions are needed: (1) better re-zoning of clam farming areas in parallel with an increase in the farm size of each household, (2) promoting sustainable linkages between the farmers and the formal financial market and output market, and (3) investing more funding into research and extension related to sustainable clam farming practices and to the improvement of farmers’ skills in cooperative works and management.