Silage preparation from tuna fish wastes and its nutritional evaluation in broilers

The present study was conducted to obtain tuna waste silage from the canning industry by using fresh fish viscera for the autolytic process. Chemical characterisation of the product and nutritional evaluation for broiler diets were then carried out. Three types of studies were performed. In study one the proximal composition was measured and three acid mixtures were tested for silage development. The formic–sulphuric acid mixture was chosen. The measurement of non-protein nitrogen (NPN) formation indicated that more than 50% NPN was obtained after 2 days of storage; pH changes were also measured and stabilisation occurred after 24 h. Contents of aerobic mesophiles, total coliforms, yeast and mould were reduced during the first month of storage. Study two was then conducted to determine the proteolytic activity in fresh viscera, the changes in lipid oxidation and the trimethylamine formation during silage development. It was observed that cooked dark meat wastes were oxidised at the beginning, but trimethylamine did not change during 2 months of storage. Thirty-nine per cent of tryptophan content was lost, but available lysine decreased only 8% from original content after 20 days of storage. Fe, Ca, P, Zn, Na and K contents were also measured. A larger batch of silage was obtained and dried after sorghum addition. The silage–sorghum ratio was 70:30. Four starter diets for 9-day-old broiler chicks were prepared at different levels from the final dried silage (5, 10 and 15%). The control diet (0%) contained soybean meal as the predominant protein supplement. Food intake, weight gain and feed conversion were recorded during the short-time feeding study. There were no significant effects of dietary inclusion on the final dried product (p < 0.05). The results showed that 15% of this product can be included without adverse effects on broilers. © 1999 Society of Chemical Industry     

太湖白鱼肌肉的营养及风味研究

本文对太湖白鱼肉的基本营养成分进行了分析,并利用固相微萃取和气质联用法分析了太湖白鱼肌肉的挥发性成分。结果表明,太湖白鱼蛋白质和脂肪含量丰富,肌肉内必需氨基酸含量高,达到41.5%。太湖白鱼肌肉内含有大量呈味氨基酸,如甘氨酸、丙氨酸和脯氨酸等,达到氨基酸总量的46.2%;同时,其肌肉内的5’-肌苷酸、5’-鸟苷酸以及对风味有益的金属离子Na+、K+、Ca2+和Mg2+等含量也十分丰富,这些物质均为太湖白鱼的非挥发性风味做出了贡献。同时,研究发现新鲜太湖白鱼肌肉的挥发性成分中含有26种,包括丰富的醇类（54.12%）、醛类（4%）及酮类（10.61%）物质,这些成分共同作用构成了太湖白鱼肌肉的香气成分。      

Process optimisation and physicochemical characterisation of potato powder

Samples of two potato cultivars (Agria and Merit), cultivated either conventionally or organically, were analysed to evaluate their suitability to transformation into powder. Agria cultivar potatoes from the conventional farming were selected as the most suitable for drying process both for their high-dry matter and good nutritional value. Blanching resulted in the most effective treatment to prevent potato browning. The potato powder was obtained by means of a drum dryer using different process parameters (temperature, time and product thickness) to minimise thermal damage on the final product. The effects of these different processes were evaluated by analysing some quality indicators, as final moisture, nutrients (carbohydrates, proteins and amino acids) and colour of the powder, and rheological properties of the rehydrated puree. The results of such analyses showed that the lower the process temperature, the better the powder quality.     

鱼油的绿色制备工艺、标准规范及营养功效研究进展北大核心CSCD

鱼油富含ω-3多不饱和脂肪酸、维生素A、维生素D和天然色素等营养物质,具有多种营养功效。为促进我国鱼油产业的绿色可持续发展,保障产品质量安全,结合国内外研究进展,分别从鱼油的绿色制备工艺、标准规范和营养功效等方面进行综述,梳理了应用于鱼油生产的水酶法、超临界流体萃取法、超声辅助提取法、微波辅助提取法等绿色制备工艺,基于国内外鱼油相关的标准规范,阐述了鱼油的基本成分和质量指标、污染物限量和添加剂限量等,探讨了鱼油在预防心血管疾病、抗炎和预防脑部疾病方面的营养功效,并针对鱼油应用中存在的问题进行了分析和展望。未来应深入研究鱼油制备新工艺,完善相关标准规范,并进一步探究其生物活性机制。     

Chemical and nutritional quality of silage made from raw or cooked lizard fish (Saurida undosquamis) and blue crab (Portunus pelagicus)

Twelve silages were prepared from uncooked or cooked lizard fish (Saurida undosquamis) and blue crab (Portunus pelagicus) and stored at ambient temperature (30 ± 2 °C) for 60 days. The antioxidative effect of adding ethoxyquin was also investigated. Generally, the nutritional quality of all the silages was stable for up to 60 days of storage and the composition of raw materials was reflected in the composition of the silages. Crab had a lower level of crude protein than fish (85 versus 162 mg kg^?1), but a higher level of ash (96 versus 36 g kg^?1); moreover, there were significant differences in nutritional composition between uncooked and cooked materials. High level of ash in crab required addition of high levels of formic acid in crab‐related silages. At the end of the experiment cooked silages showed a tendency for spoilage; in particular, maggots were observed in cooked crab silages on the last few days of the experiment. Comparison of treatments with or without ethoxyquin showed that only rancidity of fish silage groups was higher without addition of ethoxyquin. Uncooked materials are more suitable for prolonged storage than cooked materials, and it is probably not necessary to add antioxidants to silages made from material with low lipid content. Copyright © 2009 Society of Chemical Industry     

Biochemical and nutritional changes in fish proteins during drying

Biochemical and nutritional changes in the muscle proteins of a lean marine fish Nempiterus japonicus during drying at 50, 60 and 70°C were investigated. Solubility of proteins in water, 0.6 M NaCl, 1.5 M urea, 8 M urea and 10 g litre^?1 sodium dodecyl sulphate (SDS) decreased as drying progressed at all three temperatures; most of the decrease occurring in the initial 4 h of drying SDS-polyacrylamide gel electrophoresis of 1.5 M urea, 8 M urea and SDS extracts showed that higher molecular weight (MW) protein fractions were more sensitive to drying and disappeared much earlier from electropherograms than the lower MW protein fractions. Residual solubility of proteins near the pH range of 4–6 was found to increase during drying, but solubility at acid and alkaline pH was adversely affected. Decrease of solubility by drying was more affected at acid pH, especially at higher temperatures than at alkaline pH. Sulphydryl groups registered a regular and sharp decrease with drying except at 50°C, where initially an increase was observed. Apart from disulphide and hydrophobic bonds, free amino groups also appear to be involved in denaturation reactions during drying. Pepsin digestibility of fish muscle decreased slightly during drying but a clear relationship with drying temperature was not evident. Highly significant differences in proteins between protein efficiency ratio (PER), net protein utilisation (NPU) and biological value were observed between the drying temperatures. The PER and NPU of fish dried at 60°C were significantly higher than those dried at 50 or 70°C.     

Physicochemical characterisation of raw fish and stickwater from fish meal production

Chemical and microbiological properties of raw fish (RF) and chemical properties of stickwater (SW) samples were studied as a function of the staleness level of the fish. As time elapsed from fish capture increased, the microbial count in RF, volatile nitrogen content in RF and SW, and dissolved solids and dissolved protein in SW, increased. The apparent viscosity of SW increased as the temperature decreased and as the dry solids or suspended matter content increased. The size distribution of suspended particles in SW depended on the sample preparation technique, method used to measure particle size and whether the size distribution was expressed in terms of the weight or population of fractions. The average size (by weight) of suspended solids in SW was 2.5 μm as estimated by electronic counting. The solubility of protein in SW decreased when acid or alkali were added or thermal treatment (1 h at 90°C) applied. A minimal solubility point occurred near pH 5. The molecular weight of most dissolved proteins in SF was 3 kD. SF also contained a small proportion of 67 kD proteins. The significance of this basic characterisation study for the selection of improved processes for stickwater recovery is discussed.     

Stability,sensory quality,texture properties and nutritional value of fish oil‐enriched spreadable fat

A Correction has been published for this article in Journal of the Science of Food and Agriculture 84(15):2142 (2004). The intake of omega‐3 long‐chain polyunsaturated fatty acids (PUFAs) in the typical Western diet is usually below the recommended level. Without radical changes of eating patterns the diet may be enhanced by enrichment of foods with unhydrogenated fish oil, which is the richest source of the long‐chain omega‐3s, eicosapentaenoicacid (EPA) and docosahexaenoicacid (DHA). The aims of the study were to establish the sensorily acceptable fish oil enrichment level of a reduced‐fat spread, to enhance the omega‐3 long‐chain PUFA content and to evaluate the enriched spread's stability during 3 months of storage (6°C, limited exposure to light and air). Samples were prepared in an industrial pilot plant. Overall sensory quality, intensity of fishy flavour, texture properties (sensory and instrumental), peroxide value, acid number and fatty acids composition were measured. A spread enriched by addition of 30.0 g kg^?1 of unhydrogenated fish oil could be stored for up to 3 months without significant decrease of the measured stability indicators. A daily portion of this enriched spread (30 g) would provide 0.25 g of EPA and DHA, significantly increasing long‐chain omega‐3 levels in the average diet. Copyright © 2004 Society of Chemical Industry     

产卵前后长江刀鲚肉中营养成分差异

对比研究了产卵前后长江刀鲚肉的营养价值以及在产卵过程中营养成分的代谢。结果表明产卵后长江刀鲚肉粗脂肪含量显著降低（p<0.05）。两个时期的鱼肉均含有丰富的脂肪酸,尤其是单不饱和脂肪酸。产卵后大部分不饱和脂肪酸含量显著下降,而饱和脂肪酸所占比例显著上升。不饱和脂肪酸中C17∶1,C20∶4和C18∶2n6c含量下降最多,分别为97.72%,96.67%和88.77%。而C14∶1与C20∶3n6的含量发生显著性上升。产卵前后刀鲚肉中n-3/n-6为7.71、9.32,P/S为0.40、0.60。产卵后氨基酸总量显著高于产卵前（p<0.05）,分别为60.00 g/100 g和43.17 g/100 g（干重）。其中半必需氨基酸His含量升高最多,增长了85.12%。产卵前后刀鲚肉AAS值均大于100,EAAI值为157、161。产卵前后K的积累和Na的消减与刀鲚产卵时向淡水洄游的生殖洄游习性相吻合,产卵后Cu和Mn含量显著降低,用于产卵过程中维持卵巢发育。两个时期的刀鲚肉中均含有丰富的Ca。      

Comparison of check-all-that-apply and forced-choice Yes/No question formats for sensory characterisation

The application of check-all-that-apply (CATA) questions for sensory product characterisation is gaining acceptance and popularity. This question format has been reported to be a quick and reliable means of gathering sensory profiles from consumers, concurrently with hedonic assessment. However, a limitation of CATA questions is that they do not encourage deep processing by respondents. Forced-choice questions, where respondents answer “yes” or “no” for each term, may encourage systematic processing and be useful when consumers undertake sensory profiling tasks. This research compared sensory profiles elicited by consumers using CATA questions or forced-choice Yes/No questions and contribute to ongoing investigations of CATA questions and related question formats with a view to developing guidelines for best practise. Across seven consumer studies with 600+ consumers and multiple product categories, consistent evidence was obtained that forced-choice Yes/No questions are associated with higher term citation frequencies. However, this did not consistently translate into greater product discrimination. Conclusions regarding similarities and differences amongst samples and the stability of sample and term configurations were generally independent of question format (i.e., whether the sensory data were elicited by CATA or forced-choice Yes/No questions). Overall, the comparison of CATA and forced-choice Yes/No questions for sensory characterisation suggested parity of the two question formats. This extended to consumers’ perceived difficulty and tediousness for completing the test. Regardless of question format, consumers, on average, perceived the tests as easy and not tedious.     

Enzymatic hydrolysis of by‐products from the fish‐filleting industry; chemical characterisation and nutritional evaluation

Fish frames without heads from Atlantic cod and Atlantic salmon were proteolysed with the industrial enzymes neutrase®, alcalase® and pepsin for 1, 15, 30, 45, 60, 90 and 120 min. After 120 min of hydrolysis, salmon treated with alcalase and cod treated with pepsin yielded significantly (p < 0.05) higher protein recoveries (67.6 and 64% respectively) as compared to salmon treated with neutrase or pepsin and cod treated with neutrase or alcalase (53–62%). To minimise bitterness in the fish hydrolysates, kojizyme™ was added after 120 min of pre‐hydrolysis with alcalase, and the hydrolysis was run for additional times of 120, 240, 360, 480, 600 and 720 min. Protein recovery did not change significantly during the hydrolysis with kojizyme, but the degree of hydrolysis increased significantly (p < 0.01) in both the cod and salmon hydrolysates. A hydrolysate from cod treated with alcalase (150 min) followed by treatment with kojizyme (510 min) was produced. The final hydrolysate was freeze‐dried to a fish protein hydrolysate (FPH) and chemically characterised. The nutritional value of the FPH was established in an experiment with rats. Inclusion of 10% FPH‐N showed significantly (p < 0.05) higher nutritional value as compared to rats fed higher inclusion levels of FPH. © 2000 Society of Chemical Industry     

Marine and farmed fish in the Polish market: Comparison of the nutritional value

The proximate composition and fatty acids profiles of the muscle tissues of nine fish species that are popular on the Polish market were examined. The nine studied fish species were: Baltic fish (cod, herring, salmon), fish farmed in Poland (carp, trout), oceanic fish imported from China (walleye pollock, sole), and farmed fish imported from Vietnam and China (sutchi catfish, tilapia). The lowest lipid content (below 0.1%) was noted in the muscle tissues of Baltic cod and walleye pollock caught in the Pacific. The muscle tissue of walleye pollock also had the lowest protein content (12.2 ± 2.0%). The highest lipid content was noted in the muscle tissues of Baltic salmon (13.1 ± 2.4%). The highest percentage content of eicosapentaenoic (C20:5 n − 3 – EPA) and docosahexaenoic (C22:6 n − 3 – DHA) acids (over 40%) was noted in the fat extracted from the oceanic fish and Baltic cod. However, due to the low fat content, the concentrations of EPA + DHA in these fish species and in imported farmed fish expressed in mg/100 g of muscle tissues are the lowest and range on average from 24.8 ± 5.7 mg/100 g (sutchi catfish) to 207.4 ± 125.4 mg/100 g (sole). This is why the consumption of these fish species has no significant meaning for coronary heart disease prevention. Consumers with symptoms of cardiovascular diseases should include the following fish species, which have high concentrations of EPA + DHA: Baltic salmon (3807.2 ± 666.3 mg/100 g); Polish farmed trout (1804.0 ± 279.2 mg/100 g); and Baltic herring (940.9 ± 306.6 mg/100 g) in their diets. However, the consumption of Baltic salmon must be limited on account of the levels of persistent organic pollutants found in it.     

Lack of evidence that concurrent sensory product characterisation using CATA questions bias hedonic scores

In response to the growing use of consumers for sensory product characterisation, methodological research contributing to development of best practise guidelines is ongoing. We focus here on concurrent elicitation of hedonic and sensory product characterisation by check-all-that-apply (CATA) questions. Jaeger et al. (2013b) reported that CATA questions only caused weak and transient bias of co-elicited hedonic scores. In the current research six studies were conducted, in which more than 700 consumers took part. Five product categories were tested (rice crackers, lite bread, cheese, kiwifruit, black currant drinks) with 4–7 samples per study. In none of these studies was evidence obtained suggesting bias of hedonic scores and it is now possible to conclude with greater certainty that co-elicitation of hedonic scores and product attribute information using CATA questions is unlikely to bias hedonic scores. A second result of the current research was that the use of designs that rotate presentation order of CATA terms was not associated with hedonic bias, and neither was the use of the forced Yes–No CATA question format. In future research, in light of a strong dominance of positive CATA terms used in these studies, we recommend studying more thoroughly the influence of positive/negative/neutral words in CATA lists as a possible source of hedonic bias. An exploratory component to this research suggested that consumers perceive the concurrent elicitation of hedonic and CATA responses as easy, but that too many samples may make the task tedious.     

Enzymatic hydrolysis of Nile tilapia (Oreochromus niloticus) myofibrillar proteins: effects on nutritional and hydrophilic properties

Protein concentrate (PC) was prepared from eviscerated and mechanically deboned fish. The pulp was washed sequentially with 0.05 M NaCl and 4 g l^?1 NaHCO₃ solutions, with cold ethanol and then with hot (50 °C) ethanol. Subsequently, it was dried (40 °C) and ground to 60 mesh. Enzyme (Flavourzime^®) hydrolysates were prepared with a degree of hydrolysis (DH) ranging from 3.5 to 45%. The PC was characterized for proximate composition, amino acid profile, physical and functional properties. The influence of DH on functional and nutritional properties was evaluated. Hygroscopicity increased in all hydrolysates for environmental relative humidities above 40% and solubility increased rapidly for DH above 7%. Water retention, water absorption and oil absorption all decreased as a function of DH. The pH (3 to 9) influenced the water and oil absorption of the hydrolysate with 7% DH. A pH near the isoelectric point tends to decrease water absorption but increase oil absorption capacity. The insoluble fraction (IF) of the hydrolysates presented a better amino acid profile than the soluble fraction (SF). The nutritional indexes determined for the IF did not differ from the total hydrolysate, but they were consistently higher than those for the SF. Copyright © 2003 Society of Chemical Industry     

粗粮挂面感官质构及营养成分的对比分析

研究分析五种粗粮挂面的质构特性、营养成分,并对其进行感官评价。TPA结果表明:五种粗粮面条质构特性差异明显,玉米面条的质构参数值偏高,硬度314.867 g、胶着性219.352、咀嚼性208.672、弹性0.994、拉断力19.8 g、拉伸距离58.840 mm,其感官评分较高,蛋白质含量高。根据营养成分分析,每天吃50 g粗粮,玉米面条所提供的蛋白质为4.5 g,脂肪2.2 g,磷188.5 mg,钙15.5 mg,接近标准值,适合人们食用。     

The effects of rosemary extract combination with vacuum packing on the quality changes of Atlantic mackerel fish burgers

The effects of the use of antioxidant technology on the quality of mackerel burgers stored at 4 °C were investigated in terms of sensory, biochemical [thiobarbituric acid (TBA), total volatile basic nitrogen (TVB‐N), peroxide value (PV) and free fatty acids (FFA)] and microbiological analyses [total viable count (TVC)]. Fish meat was divided into three groups; the control (C) without rosemary extract, the second group with 0.4% rosemary extracts (Group A) and the third with 0.8% rosemary extracts (Group B). Results showed that the TVB‐N level did not exceed acceptability limit (30–35 mg 100 g^?1) for all groups. TBA value for the control significantly increased from 1.47 to 4.80 MA kg^?1 whereas it slightly increased in treatment groups as the storage time increased. Significantly higher PV and FFA (P < 0.05) were obtained from the control group. Rosemary extract, in combination with vacuum pack was effective in controlling the growth of bacteria and biochemical indices.     

不同贮藏方法对鸭汤营养成分和感官品质的影响

为探讨不同贮藏方法对鸭汤营养成分和感官品质的影响,以新鲜鸭汤为对照,分别研究了速冻、缓冻和高温杀菌对鸭汤感官评价、可溶性固形物、粗蛋白、氨基态氮、粗脂肪和TBARS值的影响。结果表明,速冻组鸭汤感官评价、可溶性蛋白和氨基态氮与对照组无显著差异(p>0.05),而粗蛋白和粗脂肪显著降低(p<0.05),TBARS值显著升高(p<0.05),对照组和速冻组粗蛋白分别为2.92%和2.56%、粗脂肪分别为0.53%和0.37%、TBARS值分别为0.57和0.74 mg/kg。与对照组相比,缓冻组鸭汤氨基态氮差异不显著(p>0.05),感官评价、可溶性固形物、粗蛋白和粗脂肪显著降低(p<0.05),TBARS值显著升高(p<0.05)。与对照组相比,高温组鸭汤感官评价、可溶性固形物、粗蛋白和粗脂肪显著降低(p<0.05),氨基态氮和TBARS值显著升高。此外,速冻组鸭汤感官评价、可溶性固形物和粗蛋白含量均显著高于缓冻组和高温组(p<0.05)。综上所述,速冻处理能够最大限度保持鸭汤的营养成分和感官品质,本文为汤煲产品的贮藏保鲜提供了一种新方法。      

'Fagiolo a Formella', an Italian lima bean ecotype: biochemical and nutritional characterisation of dry and processed seeds

BACKGROUND: An ecotype of the lima bean, named ‘fagiolo a Formella’, which, to the best of our knowledge, is the only example of an Italian lima bean (Phaseolus lunatus L.) ecotype, is cultivated in the Campania region of southern Italy. Physical, nutritional and processing traits of dry seeds were evaluated for two consecutive growing seasons (2009 and 2010). The canning quality was also investigated, but only for the harvest of 2010. RESULTS: Sodium dodecyl sulfate–polyacrylamide gel electrophoresis of total seed proteins allowed the attribution of ‘fagiolo a Formella’ to the Mesoamerican gene pool and Sieva morphotype. Seeds have a trapezoid shape, white coat and 100‐seed weight greater than 42 g. Yield, protein, trypsin inhibitor and phytic acid values were found comparable with those reported for lima bean varieties cultivated in sub‐tropical areas. Moreover, we found that this ecotype is devoid of lectin. CONCLUSIONS: The good adaptation to growing environment is indicated by the fact that ‘fagiolo a Formella’ seed quality is comparable to that of lima beans grown in America. Overall the canning quality was found satisfactory and canning significantly destroys the main anti‐nutritional compounds present in dry seeds. Copyright © 2012 Society of Chemical Industry     

黄鳞多孔菌营养成分分析及营养价值评价

以云南黄鳞多孔菌为原料,分析黄鳞多孔菌的营养成分,对其营养价值进行分析评价。结果表明:黄鳞多孔菌营养成分丰富,蛋白质、粗脂肪、粗纤维、总糖含量分别为2.45、0.22、1.40、61.30 g/100 g,含有钾、磷、钠、硒、钙、铁、锌等多种矿质元素和VB1、VB2。黄鳞多孔菌中包含16种氨基酸,7种人体必需氨基酸,氨基酸总含量为1829 mg/100 g,必需氨基酸占总氨基酸含量的41.61%,氨基酸评分(AAS)、化学评分(CS)、必需氨基酸指数(EAAI)、生物价(BV)、营养指数(NI)分别为68.00、60.00、81.69、77.34、2.00。药用氨基酸占氨基酸总含量的67.14%。黄鳞多孔菌是一种高营养价值的食用菌,具有良好的开发利用前景。