Effect of the Dietary Substitution of Fish Meal with Achatina fulica Meat Meal on the Growth Performance and Production Cost of African Catfish (Clarias gariepinus) Fingerlings

Fishmeal is the most preferred source of protein in aquafeeds, but it is expensive and scarce. Hence, Achatina fulica meat meal (AFM), which is much less preferred for human consumption out of three species of African giant land snails, was tested as a fishmeal substitute for Clarias gariepinus growth. Five iso-nitrogenous and iso-calorific diets were formulated, in which AFM substituted fish meal at 0% (control or Diet A), 25% (Diet B), 50% (Diet C), 75% (Diet D) and 100% (Diet E). These dietary treatments were each replicated thrice in a completely randomized design experiment, using 36-L plastic tanks in which the fish were fed daily rations corresponding to 5% of their body weight, for 8 weeks. Water quality parameters in the tanks were monitored. Proximate analyses were conducted on the fish meal, snail meal and experimental diets before the feeding trials. Cost-benefit analysis of the different diets was performed. The crude protein content of AFM (69.18%) was significantly higher than that of fish meal (55.81%). There was no significant difference (P > 0.05) in the mean weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio and survival rate in fish fed Diet A and Diet B. The best protein efficiency ratio (0.77) was recorded in fish fed Diet B. Furthermore, the survival rate of fish increased with increased levels of AFM substitution. Water quality parameters were within a suitable range for tropical fish culture, indicating that the AFM did not pollute the water. The fish fed 25% AFM diet significantly (P Clarias gariepinus diets at a 25% substitution level. The aquaculture industry can thus exploit the availability of this feed resource.

Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows

Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant sows.Seven solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were selected.In Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N source.Eight non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in Exp.1.Eight gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation stages.Results When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(P<0.05),whereas SID for Leu from SBM 5 was higher than in SBM 1 and 4(P<0.05).SID values for Ile,Ala,and Asp from SBM 4 were lower than in SBM 1 and 5(P<0.05).Sows had significantly greater SID values for Lys,Ala,and Asp during mid-gestation when compared with late-gestation stages(P<0.05).Mid-gestating sows had greater SID value for Val and lower SID value for Tyr when compared with non-pregnant and late-gestating sows(P<0.01),whereas non-pregnant sows had significantly greater SID value for Met when compared with gestating sows(P<0.01).Conclusions When fed to mid-gestating sows,the SID values for most AAs varied among SBM samples.The SID values for Lys,Met,Val,Ala,Asp,and Tyr in SBM were affected by sow gestation stages.Our findings provide a cornerstone for accurate SBM use in sow diets.

Debaryomyces hansenii supplementation in low fish meal diets promotes growth,modulates microbiota and enhances intestinal condition in juvenile marine fish

Background The development of a sustainable business model with social acceptance,makes necessary to develop new strategies to guarantee the growth,health,and well-being of farmed animals.Debaryomyces hansenii is a yeast species that can be used as a probiotic in aquaculture due to its capacity to i)promote cell proliferation and differen-tiation,ii)have immunostimulatory effects,iii)modulate gut microbiota,and/or iv)enhance the digestive function.To provide inside into the effects of D.hansenii on juveniles of gilthead seabream(Sparus aurata)condition,we inte-grated the evaluation of the main key performance indicators coupled with the integrative analysis of the intestine condition,through histological and microbiota state,and its transcriptomic profiling.Results After 70 days of a nutritional trial in which a diet with low levels of fishmeal(7%)was supplemented with 1.1%of D.hansenii(17.2×10^(5) CFU),an increase of ca.12%in somatic growth was observed together with an improve-ment in feed conversion in fish fed a yeast-supplemented diet.In terms of intestinal condition,this probiotic modu-lated gut microbiota without affecting the intestine cell organization,whereas an increase in the staining intensity of mucins rich in carboxylated and weakly sulphated glycoconjugates coupled with changes in the affinity for certain lectins were noted in goblet cells.Changes in microbiota were characterized by the reduction in abundance of several groups of Proteobacteria,especially those characterized as opportunistic groups.The microarrays-based transcrip-tomic analysis found 232 differential expressed genes in the anterior-mid intestine of S.aurata,that were mostly related to metabolic,antioxidant,immune,and symbiotic processes.Conclusions Dietary administration of D.hansenii enhanced somatic growth and improved feed efficiency param-eters,results that were coupled to an improvement of intestinal condition as histochemical and transcriptomic tools indicated.This probiotic yeast stimulated host-microbiota interactions without altering the intestinal cell organization nor generating dysbiosis,which demonstrated its safety as a feed additive.At the transcriptomic level,D.hansenii pro-moted metabolic pathways,mainly protein-related,sphingolipid,and thymidylate pathways,in addition to enhance antioxidant-related intestinal mechanisms,and to regulate sentinel immune processes,potentiating the defensive capacity meanwhile maintaining the homeostatic status of the intestine.

Screening of glucosinolates degrading lactic acid bacteria and their utilization in rapeseed meal fermentation

Rapeseed meal is a promising food ingredient, but its utilization is limited by the presence of some potentially harmful ingredients, such as glucosinolates. Fermentation is a cost-effective method of detoxication but a food-grade starter culture with glucosinolates degradation capacity is required. In this study, 46 strains of lactic acid bacteria from traditional paocai brines were screened for their ability to glucosinolate degradation. The results showed that more than 50% of the strains significantly degraded glucosinolates. Two strains of Lactiplantibacillus(p7 and s7) with high capacity of glucosinolates degradation through producing enzymes were identified. Then,an optimized condition for rapeseed meal fermentation by p7 was established to degrade glucosinolates, which can achieve about 80% degradation. UPLC/Q-TOF-MS analysis showed that the degradation rate of individual glucosinolates was different and the degradation rate of gluconapin and progoitrin in rapeseed meal can reach more than 90%. Meanwhile, fermentation with p7 can improve safety of rapeseed meal by inhibiting the growth of Enterobacteriaceae and improve its nutritional properties by degrading phytic acid. The in vitro digestion experiments showed that the content of glucosinolates in rapeseed meal decreased significantly during gastric digestion. Meanwhile, fermentation with p7 can greatly improve the release of soluble protein and increase the contents of free essential amino acids, such as lysine(increased by 12 folds) and methionine(increased by 10 folds).

Effects of Fermented Puffed Feather Meal on Growth Performance,Serum Biochemical Indices,Meat Quality,and Intestinal Microbiota in Broilers

This study aimed to investigate the effects of fermented puffed feather meal(FPFM)on growth performance,serum biochemical indices,meat quality,and intestinal microbiota in Arbor Acres(AA)broilers.A single-factor design was adopted,and four treatments were administered with five replicates to 240 one-day-old AA broilers.The control group(group A)received a basal diet,while the experimental groups received a basal diet plus 33%(group B),67%(group C)and 100%(group D)FPFM,respectively.Compared with group A,(1)the average daily gain(ADG)in group C decreased(P<0.05),and the feed conversion ratio(FCR)in group D increased(P<0.05);(2)the level of serum urea nitrogen in treatment groups decreased(P<0.05),and the levels of triglyceride,high density lipoprotein,low density lipoprotein,cholesterol,and glucose contents in group D increased(P<0.05)at day 21;(3)the serum immunoglobulin M and immunoglobulin G in group B and the immunoglobulin A in group C increased(P<0.05)at day 21,and the serum immunoglobulin M and immunoglobulin G in group D decreased(P<0.05)at day 42;(4)the share force of breast muscle and thigh muscle in group D increased(P<0.05);(5)the villus height to crypt depth ratio in the jejunum of group B increased(P<0.05)at day 21,and the villus height in group C and D increased(P<0.05)at day 42;(6)the proteobacteria counts in the cecum digesta in treatment groups decreased(P<0.05)at day 21.The basal diet supplemented with 33%FPFM promoted protein metabolism,enhanced immunity and improved meat quality,promoted the digestion and absorption of nutrients,increased intestinal microbial diversity,and improved the content of beneficial bacteria without affecting the growth performance,it was possible to be used as a good substitute for fish meal.

Comparative effects of soy protein concentrate,enzyme‑treated soybean meal,and fermented soybean meal replacing animal protein supplements in feeds on growth performance and intestinal health of nursery pigs

Background Soy protein supplements,with high crude protein and less antinutritional factors,are produced from soybean meal by different processes.This study evaluated the comparative effects of various soy protein supplements replacing animal protein supplements in feeds on the intestinal immune status,intestinal oxidative stress,mucosaassociated microbiota,and growth performance of nursery pigs.Methods Sixty nursery pigs(6.6±0.5 kg BW)were allotted to five treatments in a randomized complete block design with initial BW and sex as blocks.Pigs were fed for 39 d in 3 phases(P1,P2,and P3).Treatments were:Control(CON),basal diet with fish meal 4%,2%,and 1%,poultry meal 10%,8%,and 4%,and blood plasma 4%,2%,and 1%for P1,P2,and P3,respectively;basal diet with soy protein concentrate(SPC),enzyme-treated soybean meal(ESB),fermented soybean meal with Lactobacillus(FSBL),and fermented soybean meal with Bacillus(FSBB),replacing 1/3,2/3,and 3/3 of animal protein supplements for P1,P2,and P3,respectively.Data were analyzed using the MIXED procedure in SAS 9.4.Results The SPC did not affect the BW,ADG,and G:F,whereas it tended to reduce(P=0.094)the ADFI and tended to increase(P=0.091)crypt cell proliferation.The ESM did not affect BW,ADG,ADFI,and G:F,whereas tended to decrease(P=0.098)protein carbonyl in jejunal mucosa.The FSBL decreased(P<0.05)BW and ADG,increased(P<0.05)TNF-α,and Klebsiella and tended to increase MDA(P=0.065)and IgG(P=0.089)in jejunal mucosa.The FSBB tended to increase(P=0.073)TNF-α,increased(P<0.05)Clostridium and decreased(P<0.05)Achromobacter and alpha diversity of microbiota in jejunal mucosa.Conclusions Soy protein concentrate,enzyme-treated soybean meal,and fermented soybean meal with Bacillus could reduce the use of animal protein supplements up to 33%until 7 kg body weight,up to 67%from 7 to 11 kg body weight,and entirely from 11 kg body weight without affecting the intestinal health and the growth performance of nursery pigs.Fermented soybean meal with Lactobacillus,however,increased the immune reaction and oxidative stress in the intestine consequently reducing the growth performance.

Sanitary Quality of the Meals Served in the Canteens and Vicinity of the Lagoon Mother and Child University Hospital Centre and National Hospital and University Centre Hubert Koutoukou Maga of Cotonou (Benin)

Background: Food safety is an integral part of food security. It refers to the protection of the food supply against risks of microbial, chemical and physical origin at every stage of the food chain. The study aimed to investigate the sanitary quality of meals served in the canteens and vicinity of the Lagoon Mother and Child University Hospital Centre (CHU-MEL) and National Hospital and University Centre Hubert Koutoukou Maga (CNHU-HKM) of Cotonou. Methods: It was a cross-sectional with a data collection period from 16 March to 22 April 2021. There were 32 vendors surveyed and 40 meals sampled for microbiological examination. We collected data on the vendors’ socio-demographic characteristics, working environment, health status, knowledge and food hygiene practices. Results: About 83% of the meals contained pathogenic microorganisms. All meals had a temperature from 4°C to 60°C called the “danger zone”. The level of knowledge about food hygiene was low in 65.7% of the vendors. About 47% had poor personal and clothing hygiene, food storage and service practices. Conclusion: These results show that the meals sold in the CHU-MEL and CNHU-HKM could present a health risk for the consumer. There is a need for improvement of the sanitary quality of the meals delivered in the canteens and vicinity of these hospitals.

Evaluation of Nutritional Value and Safety of Black Soldier Flies Fed on Dead Pig Meat and Bone Meal

[Objectives]This study was conducted to evaluate the nutritional value and safety of black soldier flies fed with dead pig meat and bone meal(DPMBM)and to explore the resource utilization of DPMBM.[Methods]The general nutrient composition,amino acids,fatty acids and mineral elements of black soldier fly meal(BSLM)were detected and analyzed.[Results]The results showed that the contents of moisture,crude protein,crude fat and ash in BSLM were 3.42%,42.31%,34.04%and 5.40%,respectively.The contents of total amino acids(TAA),essential amino acids(∑EAA)and non-essential amino acids(∑NEAA)and umami amino acids(∑DAA),the EAA/TAA value and the EAA/NEAA value were 37.93%,13.08%,24.85%,13.43%,34.47%,52.61%,respectively.A total of eight kinds of saturated fatty acids and seven kinds of unsaturated fatty acids were detected,accounting for 63.65%and 32.67%of the total fatty acids.Among the major mineral elements,the content of Ca was the highest,followed by K,Mg and Na.Among the trace mineral elements,the content of Mn was the highest,followed by Fe,Zn,Cu,Ni,Cr,Cd,As,Pb,Se,Sn,Ti,Sb and Hg.The contents of heavy metal mineral elements in BSLM were far lower than the limits specified in Hygienical Standard for Feeds.[Conclusions]In conclusion,BSLM has high nutritional value and good safety of heavy metals,and thus great potential for development and utilization as a high quality dietary protein,fat and mineral elements source.

花生粕的饲用资源开发及在养殖业的应用

花生粕粗蛋白含量和代谢能均高于大豆饼粕,但缺乏赖氨酸、蛋氨酸等,且赖氨酸与精氨酸比例失衡,蛋白质品质欠佳。花生粕极易感黄曲霉毒素,同时在高温压榨条件下,蛋白质变性严重,导致蛋白质和氨基酸的利用率降低。由于花生粕自身品质缺陷和加工质量的不稳定性,限制了其在配合饲料中的应用。利用微生物发酵或菌酶协同发酵技术,可使花生粕中含有丰富的益生菌、寡肽、有机酸等,改善其适口性,有效降解霉菌毒素或抗营养因子,有利于改善动物肠道健康,增强机体免疫,提高生产性能,缓解蛋白质原料匮乏的现状。文章综述了花生粕资源状况、营养特性、生物发酵花生粕研究现状及在养殖业中的应用,为花生粕安全高效可持续利用提供参考依据。

魔芋果蔬健康代餐粉的功能特性

研究了不同杀菌条件对自制代餐粉功能特性及产品品质的影响,紫外冷杀菌可以最大限度地保留代餐粉原来的功能特性,但是杀菌效率不高;而射频杀菌既可以保留功能性成分又可以取得良好的杀菌效果。将自制代餐粉与市售代餐粉进行对比,结果表明自制代餐粉总酚质量分数及抗氧化活性均高于市售代餐粉,且自制代餐粉的风味滋味均优于市售代餐粉。为研究自制代餐粉的贮藏稳定性,对自制代餐粉进行了3个月的贮藏实验。结果表明,自制代餐粉在90 d的贮藏期内功能特性、微生物指标均在标准范围内。为了延长代餐粉的保质期,应尽可能将代餐粉置于干燥、阴凉处贮藏。

脱酚棉籽蛋白替代豆粕对凡纳滨对虾生长、饲料利用和免疫应答的影响

为研究脱酚棉籽蛋白替代凡纳滨对虾(Litopenaeus vannamei)饲料中豆粕的效果,以初始体质量为(0.81±0.01) g的凡纳滨对虾为研究对象,进行6周的养殖实验。对照组饲料中豆粕含量为25%(编号为S0),分别用4.93%、10.06%、14.80%、19.73%的脱酚棉籽蛋白等蛋白替代25%、50%、75%、100%的豆粕(分别编号为S25, S50, S75, S100)。每个处理3个重复,每个重复70尾对虾。实验表明,与对照组相比,脱酚棉籽蛋白替代100%豆粕对对虾的生长和饲料利用无显著影响,但显著降低了胰蛋白酶和淀粉酶活性,显著降低了干物质和粗蛋白表观消化率。与对照组相比,脱酚棉籽蛋白替代75%豆粕时,对虾肠道中免疫相关基因的表达显著升高。肠道组织形态学观察实验表明,脱酚棉籽蛋白替代100%豆粕会影响对虾的肠道健康,肠道绒毛高度显著降低。结果表明,脱酚棉籽蛋白替代饲料中100%的豆粕不会对凡纳滨对虾的生长和饲料利用产生显著影响,但会影响对虾的消化、免疫应答以及肠道健康。

液态饲喂杂粕型饲粮对生长猪生长性能、养分消化率、血清炎性因子及粪便短链脂肪酸含量的影响

本试验旨在研究液态饲喂杂粕型饲粮对生长猪生长性能、养分消化率、血清炎性因子及粪便短链脂肪酸(SCFAs)含量的影响。选取平均体重为(30.00±4.26)kg的“杜×长×大”三元杂交猪126头,随机分为3组,每组7个重复,每个重复6头猪。试验Ⅰ组饲喂豆粕型颗粒饲粮;试验Ⅱ组饲喂杂粕型颗粒饲粮(由双低菜籽粕、玉米胚芽粕、喷浆玉米皮及米糠替代部分豆粕和玉米组成);试验Ⅲ组饲喂杂粕型液态饲粮,即在杂粕型饲粮的基础上加入2.7倍的水,混合均匀后饲喂。各组饲粮营养水平基本一致。试验期56 d。结果表明:1)试验全期,与试验Ⅰ组相比,试验Ⅱ组平均日采食量和平均日增重分别降低了2.29%和5.33%(P>0.05),料重比提高了3.40%(P>0.05);与试验Ⅱ组相比,试验Ⅲ组平均日采食量和平均日增重分别提高了7.04%(P<0.05)和6.32%(P>0.05)。2)试验Ⅱ组和试验Ⅲ组干物质、总能和粗蛋白质消化率极显著低于试验Ⅰ组(P<0.01),粗脂肪、磷和粗灰分消化率显著低于试验Ⅰ组(P<0.05)。试验Ⅱ组和试验Ⅲ组间各养分消化率均无显著差异(P>0.05)。3)试验Ⅲ组粪便丁酸含量显著高于试验Ⅱ组(P<0.05),与试验Ⅰ组差异不显著(P>0.05)。4)与试验Ⅰ组相比,试验Ⅱ组和试验Ⅲ组血清抗炎因子白细胞介素-10(IL-10)含量极显著提高(P<0.01),试验Ⅱ组血清促炎因子白细胞介素-1β(IL-1β)和肿瘤坏死因子-α(TNF-α)含量显著提高(P<0.05);与试验Ⅱ组相比,试验Ⅲ组血清IL-1β含量显著降低(P<0.05),血清白细胞介素-6(IL-6)、白细胞介素-2(IL-2)和TNF-α含量有一定程度降低但未达到显著水平(P>0.05)。综上可知,与豆粕型颗粒饲粮相比,杂粕型颗粒饲粮会降低生长猪采食量和养分消化率,提高血清炎性因子含量,而通过液态方式饲喂杂粕型饲粮可改善饲粮适口性,提高生长猪采食量,降低血清促炎因子IL-1β含量,对养分消化率无改善作用。

玉米蛋白粉替代豆粕对肉牛生长性能、氮代谢及屠宰性能的影响

文章旨在研究玉米蛋白粉(Corn Gluten Meal,CGM)替代豆粕对肉牛生长性能、氮代谢及屠宰性能的影响。试验将96头健康、370 kg左右的西门塔尔肉牛随机分为4组,每组3个重复,每个重复8头。CON组根据肉牛饲养标准(NY/T 815-2004)配制全混合日粮,其余3组在全混合日粮中分别添加2.5%(CGML组)、5.0%(CGMM组)、7.5%(CGMH组)的玉米蛋白粉(等氮替代豆粕),试验为期80 d。结果表明:(1)与CON组相比,CGMH组肉牛的末重、平均日增重显著降低(P<0.05),料重比显著提高(P<0.05)。4组中CGML组肉牛的末重、平均日增重最高,料重比最低。(2)与CON组相比,CGMM组、CGMH组肉牛的沉积氮、氮利用率显著降低(P<0.05),CGML组肉牛的沉积氮、氮利用率高于CON组,但无显著差异(P>0.05)。(3)与CON组相比,CGMH组肉牛的宰前活重、胴体重、净肉重均显著降低(P<0.05)。4组中CGML组肉牛的宰前活重、胴体重、净肉重最高。结论:综合各项指标,在不考虑饲料成本的情况下,肉牛全混合日粮中玉米蛋白粉的适宜添加水平为2.5%。

无鱼粉无豆粕饲料中补充蛋氨酸对鲤生长性能、氮循环和氨基酸沉积率的影响及补充晶体氨基酸饲料的投喂策略

本试验旨在研究无鱼粉无豆粕饲料中补充蛋氨酸对鲤生长性能、氮循环和氨基酸沉积的影响,以及投喂频率和补充蛋氨酸对鲤餐后血浆氨基酸含量的影响。选取初始体重为27 g的鲤幼鱼540尾,随机分为2组(每组9个重复,每个重复30尾),分别投喂添加0(C组)和3 g/kg蛋氨酸(DL-蛋氨酸形式,纯度为98%)(M组)的无鱼粉无豆粕饲料,2种试验饲料中蛋氨酸含量分别为3.85和6.83 g/kg饲料(1.14和1.99 g/16 g N),进行为期8周的生长试验。生长试验结束后称重,采样后继续进行1周的投喂频率试验。投喂频率试验中,将C组和M组试验鱼分别随机分为3组,投喂频率分别为1、2和3次,共6组,每组3个重复,每个重复25尾。采集餐后不同时间点血浆样品,测定血浆游离氨基酸含量。结果显示:1)在无鱼粉无豆粕饲料中补充蛋氨酸显著提高了鲤的总摄食量、特定生长率和蛋白质效率(P<0.05),显著降低了摄食率和饲料系数(P<0.05);2)与C组相比,M组鲤氮摄入量从54.33 g/桶显著提高到60.73 g/桶(P<0.05),但氮排放量从41.08 g/桶显著降低到37.93 g/桶(P<0.05),各氨基酸以及总必需氨基酸和总非必需氨基酸沉积率均显著提高(P<0.05),血浆尿素氮和总胆固醇含量显著下降(P<0.05);3)投喂频率达到3次时,饲料中补充蛋氨酸可显著提高鲤血浆蛋氨酸、赖氨酸曲线下面积(AUC)(P<0.05)。综上所述,在无鱼粉无豆粕饲料中补充蛋氨酸至鲤需求量,在日投喂3次的养殖模式下,鲤的生长性能得到显著改善,饲料效率和氮沉积率显著提高,说明提高投喂频率是提高晶体氨基酸利用率的有效方法。

响应面法优化藜麦代餐粉工艺

以催芽藜麦粉、木糖醇、黑芝麻粉、脱脂奶粉为原料,以上述原料所占质量百分比及感官评价为指标进行单因素对照试验。在单因素试验的基础上,选取催芽藜麦粉用量为6.40 g,木糖醇用量为6.99 g,脱脂奶粉用量为10.36 g,羧甲基纤维素钠用量0.80 g,黑芝麻粉用量4.00 g作为优化因素进行响应面法分析,结果表明,各因素对结果的影响排序为催芽藜麦粉>木糖醇>脱脂奶粉。

低温/中温花生粕蛋白的理化特性及结构特性分析

对低温/中温花生粕的感官色差、功能特性和结构特性进行了研究和分析,旨在为提高花生粕的综合利用价值提供理论基础。结果表明,低温花生粕呈象牙色,中温花生粕呈灰白色。从功能特性上来看,低温/中温花生粕蛋白的持油性、乳化性和泡沫稳定性无显著性差异。低温花生粕蛋白具有更好的溶解度、起泡性、持水性、热稳定性,中温花生粕蛋白具有更好的乳化稳定性。进一步通过分子量、二级结构、DSC对蛋白质结构进行分析,低温花生粕和中温花生粕蛋白质二级结构主要是β-折叠、β-转角,中温花生粕蛋白变性程度更高,低温花生粕的蛋白结构相对更松散。低温花生粕蛋白具有更高的变性温度和热焓值,且具有更好的热稳定性。

大口黑鲈饲料营养需求及鱼粉替代研究进展

水产养殖动物的精准营养需求参数对其配合饲料的优化或者开发至关重要。文章概述了大口黑鲈蛋白质、脂肪、矿物质、碳水化合物以及维生素等主要元素需求以及蛋白源替代研究,对大口黑鲈饲料配制和降低成本等有重要的指导意义。

基于HS-GC-IMS和HS-SPME-GC-MS的蛋白酶对豆粕挥发性风味的影响分析

为研究不同蛋白酶酶解对豆粕挥发性风味成分的影响,选用4种蛋白酶(碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、风味蛋白酶)对豆粕进行酶解,采用顶空-气相色谱-离子迁移谱(Headspace-gas chromatography-ion mobility spectroscopy,HS-GC-IMS)和顶空固相微萃取-气相色谱-质谱(Headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用技术分析不同豆粕酶解物(Soybean meal hydrolysates,SMH)的挥发性风味成分,并结合主成分分析(Principal component analysis,PCA)、热图聚类和正交偏最小二乘判别法(Orthogonal partial least squares-discriminant analysis,OPLS-DA)对不同SMH进行分析。结果表明:碱性蛋白酶、中性蛋白酶、木瓜蛋白酶和风味蛋白酶酶解豆粕的挥发性风味成分存在较大差异。HS-GC-IMS鉴定出84种挥发性成分,筛选得到33种差异风味物质,发现酶解后酮类物质显著降低而醛类、醇类和酯类物质含量明显增加。PCA结果表明不同SMH之间的风味存在显著差异。最终通过OPLS-DA筛选出贡献较大的挥发性化合物,同时构建出可靠的用以鉴别SMH的模型。HS-SPME-GC-MS检测出103种差异风味物质,可用于区分不同SMH,被检出的挥发性组分中醛类、醇类和酮类等化合物为SMH风味的形成做出主要贡献,明晰了部分风味化合物形成的原因。PCA和聚类热图结果表明不同蛋白酶酶解对豆粕的挥发性风味物质的种类和含量有显著影响,其中,风味蛋白酶和木瓜蛋白酶对豆粕的风味改善最为显著。

北京市60岁及以上老年人三餐就餐情况分析

目的:了解北京市60岁及以上老年人三餐就餐情况及影响因素。方法:利用2015年中国成人慢性病与营养监测中北京市60岁及以上老年人的数据,分析三餐就餐情况及其影响因素。结果:北京市60岁及以上老年人的每日三餐的比例为77.5%,每日早餐为86.5%,每日午餐为88.1%,每日晚餐为92.4%。60岁及以上老年人早餐、午餐及晚餐最主要食物均来自家庭制作的比例分别为82.1%、81.8%、85.7%。多因素Logistic回归模型分析结果显示,家庭月收入越高、腰围不适宜者、每日身体活动时间≥30 min/d及不饮酒的老年人每日三餐的比例高(均P<0.05);年龄越高早餐来自家庭制作的比例高(P<0.05);家庭月收入越高、高密度脂蛋白不正常者及不饮酒的老年人午餐来自家庭制作的比例高(均P<0.05);不饮酒的老年人晚餐来自家庭制作的比例高(P<0.05)。结论:北京市60岁及以上老年人每日三餐的比例和三餐食物来自家庭制作的比例均较低,急需相关部门开展有针对性的干预,让更多的老年人每日三餐都有保障。

紫苏副产物籽粕中黄酮的提取新工艺

优化离子液体辅助微波法提取紫苏籽粕中的黄酮工艺,为进一步高值化利用紫苏籽粕废弃物提供依据。将离子液体加至提取溶剂中辅助微波法提取紫苏籽粕中的黄酮。以总黄酮提取率为指标,在单因素实验结果的基础上结合响应曲面设计优化最佳提取条件,HPLC测定咖啡酸、木犀草苷、迷迭香酸、槲皮素、木犀草素等成分的含量,探究不同方法对紫苏籽粕中黄酮提取的变化规律。最佳提取条件为微波功率860 W,V(提取液)∶m(原料)=30 mL/g,V(乙醇)∶V(离子液体)=10,t=70℃,紫苏籽粕黄酮的实际提取率为3.18%,与预测值3.1769%接近。HPLC测定黄酮含量,离子液体法提取黄酮成分含量均高于传统方法。微波辅助离子液体提取紫苏籽粕黄酮的新方法具有可行性。