Incorporation of Uncertainty in Composition of Feeds into Least-Cost Ration Models. 1. Single-Chance Constrained Programming

Ration formulation by linear programming techniques assumes a perfect knowledge of all coefficients involved. Because of variation in composition of feedstuffs, this assumption cannot hold in practical situations. However, the problem can be reformulated as a chance-constrained programming model for which a deterministic equivalent can be derived. In the case where only one nutrient is considered random, the methodology is labeled as single-chance constrained programming. The exact deterministic equivalent requires nonlinear programming methods for which algorithms are not available to the feed industry. Three linear approximation algorithms were derived and compared with the exact solution given by nonlinear programming in the formulation of a premix feed. Prices from 1970 to 1979 for 17 feed ingredients were used. An algorithm based on a linear function of the standard deviation of the random nutrient within each feedstuff, for which a penalty parameter is iterated in a search for a desired probability, yielded results very similar to the exact solutions found by nonlinear programming methods. This methodology could be implemented easily by the feed industry.     

Uncertainty in Composition of Ingredients and Optimal Rate of Success for a Maximum Profit Total Mixed Ration

Chance constrained programming methodology, which accounts for uncertainty in composition of feedstuffs, was applied to a total mixed ration set for a 650-kg cow producing 27.2 kg of milk/d. Available ingredients were legumegrass hay, legume-grass silage, corn silage, high moisture ground ear corn, soybean meal, dry fat, and a mineral mix. Four models were derived and their performances were compared when both net energy for lactation and crude protein were considered as random constraints. A model based on a Bonferroni inequality with unequal weight on rows’ probability appeared to be best over the range of probability considered (.5 to .95). The value of a feed analysis program was assessed by reducing variances in composition of farm-grown ingredients to those equivalent to a coefficient of variation of 3%. Also, an approximate method was derived for assessing the optimal rate of success. It appears that the optimal rate of success is close to .6 and is not greatly affected by a feed analysis program or a change in price of milk. However, such a program increases income over feed cost by an estimated 27 e/cow per d.     

胶原蛋白饲料粉的制备、组成分析及在饲料中的应用

研究了从新鲜猪皮中提取胶原蛋白粉的制备工艺,结合傅立叶变换红外光谱对提取胶原蛋白的结构进行鉴定以及采用高效液相色谱对胶原蛋白的氨基酸组成进行分析,并概述了胶原蛋白粉在饲料行业的应用前景。     

高氯酸湿消化-原子荧光光度法测定饲料中总砷的不确定度评定

对高氯酸湿消化法处理饲料样品后用原子荧光光度法测定总砷含量的测量不确定度进行了评定。通过建立测量过程中各分量的数学模型,分析、识别了不确定度来源,其测量不确定度来源于样品测试液总体积、样品称量、样品重复测定、回收率、标准物质、标准曲线等因素,估算出各不确定度分量对测量不确定度的影响,在对各不确定度分量进行量化的基础上,合成得到了测量结果的相对标准不确定度。结果表明,样品重复测定和回收率,是影响该方法不确定度的主要因素,从而为采用该方法测定饲料中总砷含量的质量控制提供了理论依据。     

Stress Relaxation of Fruit Gels. Evaluation of Models and Effects of Composition

Stress relaxation behavior of kappa carrageenan (1%) gels (C) and kappa carrageenan (0.5%) plus locust bean gum (0.5%) gels (G) was studied. Effects of addition of sugar (18.3, 36.6 and 55° Brix) and fruit pulp (15%) on relaxation response were analyzed. Curves were fitted to Maxwell (M), Peleg (P) and simplified Maxwell (SM) equations. All three equations were valid to quantify relaxation behavior of fruit gels and to evaluate the effects of changes in composition, with P and SM equations being simpler. Locust bean gum increased initial stress decay rate and decreased proportion of unrelaxed force. Sucrose produced the opposite effect. Fruit pulp effects were weak and dependent on gelling system.     

Different Approaches for Digestion,Performance Assessment and Measurement Uncertainty for the Analysis of Cadmium and Lead in Feeds

Certain feedingstuffs are sources of contamination for animals with cadmium (Cd) and lead (Pb). Different approaches for sample digestion, performance assessment, and measurement uncertainty for the analysis of Pb and Cd by flame atomic absorption spectrometry were compared. Full method validation, including matrix effect and analytical limits, were assessed. Despite having a lower performance compared to the microwave digestion, dry ashing was a viable alternative for sample digestion, leading to lower operating costs. Interlaboratory validation proved to be a cheaper alternative, instead of the long traditional in-house approach. The method was suitable for routine analysis of several feed samples. There was a greater amount of quantifiable results for Pb, ranging from traces up to high concentrations (7430 ± 930 mg kg^-1). Cd was also quantified in some samples, ranging from 0.11 ± 0.01 to 8.71 ± 0.90 mg kg^?1. The higher concentrations of both metals were found in mineral mixtures and fish meal.     

Composition of Montmorency Cherry Essence. 2. High-boiling Components

SUMMARY: Volatile components of commercial Montmorency cherry essence boiling above ethanol were extracted from the essence by ether and concentrated by distillation. This concentrate was fractionated by gas chromatography. Individual components were identified using the methods of functional group analysis, gas co-chromatography, infrared analysis and mass spectrometry. The concentrations of the components in the original essence were estimated. The major components identified were n-propyl alcohol, isobutyl alcohol, isoamyl alcohol, and benzaldehyde. Minor components identified include n-butanol, n-hexanol, a hexenol, benzyl alcohol, α-terpineol, furfural, isoprene, myrcene and numerous higher terpenes, methyl benzoate, ethyl benzoate, benzyl acetate, ethyl caprylate, ethyl caprate, n-propyl benzoate, isobutyl benzoate, isoamyl benzoate and di-butyl phthalate.     

Incorporation of Mg and Ca into nanostructured Fe2O3 improves Fe solubility in dilute acid and sensory characteristics in foods

Iron deficiency is one of the most common micronutrient deficiencies worldwide. Food fortification can be an effective and sustainable strategy to reduce Fe deficiency but selection of iron fortificants remains a challenge. Water-soluble compounds, for example, FeSO(4), usually demonstrate high bioavailability but they often cause unacceptable sensory changes in foods. On the other hand, poorly acid-soluble Fe compounds, for example FePO(4), may cause fewer adverse sensory changes in foods but are usually not well bioavailable since they need to be dissolved in the stomach prior to absorption. The solubility and the bioavailability of poorly acid-soluble Fe compounds can be improved by decreasing their primary particle size and thereby increasing their specific surface area. Here, Fe oxide-based nanostructured compounds with added Mg or Ca were produced by scalable flame aerosol technology. The compounds were characterized by nitrogen adsorption, X-ray diffraction, transmission electron microscopy, and Fe solubility in dilute acid. Sensory properties of the Fe-based compounds were tested in 2 highly reactive, polyphenol-rich food matrices: chocolate milk and fruit yoghurt. The Fe solubility of nanostructured Fe(2)O(3) doped with Mg or Ca was higher than that of pure Fe(2)O(3). Since good solubility in dilute acid was obtained despite the inhomogeneity of the powders, inexpensive precursors, for example Fe- and Ca-nitrates, can be used for their manufacture. Adding Mg or Ca lightened powder color, while sensory changes when added to foods were less pronounced than for FeSO(4). The combination of high Fe solubility and low reactivity in foods makes these flame-made nanostructured compounds promising for food fortification. Practical Application: The nanostructured iron-containing compounds presented here may prove useful for iron fortification of certain foods; they are highly soluble in dilute acid and likely to be well absorbed in the gut but cause less severe color changes than FeSO(4) when added to difficult-to-fortify foods.     

Prediction of Average Daughter Performance from Sire Proofs for Use in Linear Programming Sire Profit Models

When linear programming is used to rank sires on daughter profits, coefficients of input are required for representative daughters of each sire. Within herd-year-season regressions of daughter's actual 305-day milk, fat percent, days open, 2-min milk yield adjusted for total yield, total milking time, and body weight at birth and first calving on sire's proofs for production, conformation, milking speed, and nonreturn rate were computed from progeny data from 71 Canadian Holstein-Friesian artificial insemination sires, to provide these coefficients. Coefficients of determination for prediction equations were .23 to .71. A production function was fitted for milk production and days open. First lactation 305-day milk was predicted from sire's milk rating and linear and quadratic terms of size ratings. Fat percent proof and its squared term predicted daughter's fat percent. Days open was predicted by milk and fat proofs. Milk yield in the first 2-min of milking, adjusted for milking yield, was predicted by proofs for milking speed and the quadratic term for fat percent. Total milking time was obtained from 2-min yield by regression (?.3837) of total milking time on 2-min yield. Daughter's body weight at first calving was predicted from sire's size proof, as was birth weight. Milk yield was curvilinearly associated with days open. Incidence of mastitis was derived indirectly from regression (.00172) on sire's milk proof for milk.     

Photochemical modeling of emissions trading of highly reactive volatile organic compounds in Houston, Texas. 2. Incorporation of chlorine emissions

As part of the State Implementation Plan for attaining the National Ambient Air Quality Standard for ozone, the Texas Commission of Environmental Quality has created a Highly Reactive Volatile Organic Compounds (HRVOC) Emissions Cap and Trade Program for industrial point sources in the Houston/Galveston/Brazoria area. This series of papers examines the potential air quality impacts of this new emission trading program through photochemical modeling of potential trading scenarios; this paper examines the air quality impact of allowing facilities to trade chlorine emission reductions for HRVOC allocations on a reactivity weighted basis. The simulations indicate that trading of anthropogenic chlorine emission reductions for HRVOC allowances at a single facility or between facilities, in general, resulted in improvements in air quality. Decreases in peak 1-h averaged and 8-h averaged ozone concentrations associated with trading chlorine emissions for HRVOC allocations on a Maximum Incremental Reactivity (MIR) basis were up to 0.74 ppb (0.63%) and 0.56 ppb (0.61%), respectively. Air quality metrics based on population exposure decreased by up to 3.3% and 4.1% for 1-h and 8-h averaged concentrations. These changes are small compared to the maximum changes in ozone concentrations due to the VOC emissions from these sources (5-10 ppb for 8-h averages; up to 30 ppb for 1-h averages) and the chlorine emissions from the sources (5-10 ppb for maximum concentrations over wide areas and up to 70 ppb in localized areas). The simulations indicate that the inclusion of chlorine emissions in the trading program is likely to be beneficial to air quality and is unlikely to cause localized increases in ozone concentrations ("hot spots").     

不同养殖模式金刚虾（斑节对虾）肌肉营养成分比较分析

探究金刚虾（Penaeus monodon）不同养殖模式下肌肉营养成分的组成,旨在为后续产业精加工提供理论依据,并根据需要选择合适模式的金刚虾。以低盐土池养殖（盐度：8.3‰,简称低盐土池组）、低盐高位池养殖（盐度：7.8‰,简称低盐高位池组）和高盐高位池（盐度：23.4‰,简称高盐组）养殖3种养殖模式下的金刚虾为试验对象,通过对肌肉营养成分的分析比较,研究金刚虾肌肉在不同养殖模式下的营养差异。结果表明,在常规营养成分方面,高盐组金刚虾肌肉水分含量显著低于低盐高位池组和低盐土池组(P<0.05),低盐高位池组粗蛋白含量显著低于高盐组和低盐土池组(P<0.05),高盐组粗脂肪、灰分含量最高,与其他两组差异显著(P<0.05)。在氨基酸组成方面,3种养殖模式饲养的金刚虾肌肉均含17种氨基酸,高盐组金刚虾肌肉必需氨基酸含量、鲜味+甜味氨基酸含量、氨基酸总量均最高。在必需氨基酸评价方面,高盐组金刚虾肌肉必需氨基酸总量（2336.27 mg/g N）和必需氨基酸指数（76.15）最高,低盐高位池组次之,低盐土池组最低。在脂肪酸组成方面,共检测出17种脂肪酸,3种养殖模式下金刚虾...     

利用Excel的图表函数化功能使试差计算程序化

以黑液多效蒸发设计型计算为例,介绍用Excel实现图表数据函数化的方法。通过图表数据函数化可以使试差计算程序化,因而有效减少试差计算时间,还能方便地调节有关参数。     

The Incorporation of Curcuminoids in Gamma-Cyclodextrins Improves Their Poor Bioaccessibility,Which Is due to Both Their Very Low Incorporation into Mixed Micelles and Their Partial Adsorption on Food

Scope

Turmeric curcuminoids mainly consist of curcumin (CUR), demethoxycurcumin (dCUR), and bisdemethoxycurcumin (bdCUR). CUR displays low bioavailability, partly due to poor solubilization in the intestinal lumen during digestion, while data for dCUR and bdCUR are scarce. The study aims to investigate the bioaccessibility of curcuminoids from turmeric extracts or from gamma-cyclodextrins, considering potential interactions with food.

Methods and results

Using an in vitro digestion model (correlation with CUR bioavailability: r = 0.99), the study shows that curcuminoid bioaccessibility from turmeric extract without food is low: bdCUR (11.5 ± 0.6%) > dCUR (1.8 ± 0.1%) > CUR (0.8 ± 0.1%). Curcuminoids incorporated into gamma-cyclodextrins display higher bioaccessibilities (bdCUR: 21.1 ± 1.6%; dCUR: 14.3 ± 0.9%; CUR: 11.9 ± 0.7%). Curcuminoid bioaccessibility is highest without food (turmeric extract: 2.0 ± 0.1%; gamma-cyclodextrins: 12.4 ± 0.8%) and decreases with a meat- and potato-based meal (turmeric extract: 1.1 ± 0.2%; gamma-cyclodextrins: 2.4 ± 0.3%) or a wheat-based meal (turmeric extract: 0.1 ± 0.0%; gamma-cyclodextrins: 0.3 ± 0.1%). Curcuminoids exhibit low (<10%) incorporation efficiencies into synthetic mixed micelles (bdCUR > dCUR > CUR).

Conclusions

bdCUR and dCUR show greater bioaccessibilities versus CUR. Food diminishes curcuminoid bioaccessibility, likely by adsorption mechanisms. Gamma-cyclodextrins improve curcuminoid bioaccessibility.     

Importance and utilization of amaranth in food industry. Part 2. Composition of amino acids and fatty acids

Content of amino acids and fatty acids in whole amaranth flour from Amaranthus hypochondriacus was investigated. In comparison with fine wheat flour, used in our experiments, high lysine content was observed (5,95 g/16 g N in comparison with 2,90 g/16 g N). Similarly, a higher amount of essential amino acids in amaranth was found. The highest content from fatty acids had linoleic acid about 50%. On the basis of the results obtained, the analysed raw material proves to be very valuable for the enrichment of some cereal products especially regarding protein content, amino acid composition, mainly essential ones, fatty acid composition, and some important mineral substances and vitamins. It is expected, that amaranth will be utilized in some branch of food industry as well.     

A Study of the Forces Involved in the Incorporation of L-Methionine into Soy Protein by the One-Step Plastein-Like Process

Ultrafiltration was used to study the forces involved in the incorporation of methionine into soy protein. Various solvents were used to determine the extent of noncovalent binding. When analyzed with 0.2M citric acid, 60% of the methionine was incorporated into the soy protein. However, when analyzed with 8M Guanidine HCl and 3M KSCN the incorporation was only 20 and 13%, respectively. This reduction in percent incorporation of methionine by protein denaturants indicates that it was not incorporated by covalent bonds. Incorporation is probably due to hydrophobic attraction of the side chain of methionine with apolar regions in the protein.     

前纺重定量与细纱牵伸型式和胶辊胶圈纺纱性能的研试

前纺重定量是棉纺工程技术发展的方向,为了提高棉纱质量,应遵循纺纱牵伸原理.对前纺重定量的负面效应,研试对策,细纱采用V型牵伸气动加压并配置高弹性、低硬度、重加压胶辊;根据细纱不匀产生机理同时降低前纺、细纱工艺流程附加不匀率,前纺并、粗、精胶辊也向高弹性、低硬度、重加压等适纺纱性发展.     

高效液相色谱法测定化妆品中苯氧乙醇含量的不确定度评定

目的评定《化妆品中防腐剂的检测方法(征求意见稿)》中高效液相色谱法测定化妆品中苯氧乙醇含量的不确定度。方法依据国家计量技术规范JJF 1059.1-2012《测量不确定度评定与表示》对苯氧乙醇测定中的不确定度来源进行分析。通过建立数学模型量化不确定度分量,计算合成不确定度和扩展不确定度。结果当样品中苯氧乙醇的含量为0.439%时,扩展不确定度为0.016%,苯氧乙醇含量表示为0.439%±0.016%。结论该方法测量化妆品中苯氧乙醇含量的不确定度总体较小,方法相对准确可靠。此次评定的不确定度主要来源为重复性测量、标准曲线配制和样品定容3个方面。