Proximate Composition Analysis Research Articles

Nutrition composition differences among steamed and freeze-dried mature silkworm larval powders made from 3 Bombyx mori varieties weaving different colored cocoons

The mulberry silkworm, Bombyx mori has been one of the most important domestic animals which have provided with silk fibers for weaving fabrics and a food for a protein and lipid source. In addition, various health improvement effects of diverse silkworm larval powders were reported. Recently we found that steamed and freeze-dried mature silkworm larval powder (SMSP) generated using white-jade (also known as Backokjam) silkworm variety extended healthspan and increased resistance to Parkinson`s disease in animal models. Because the colors of cocoons in silkworm varieties were caused by altered signal transduction pathways transporting phytochemicals from intestinal lumens to silk glands, we performed the proximate, amino acid, mineral, carbohydrates, fatty acid, and cholesterol composition analyses of SMSPs of 3 silkworm varieties which were weaving light yellow, golden, and red cocoons. Although most of nutrient compositions among 3 SMSPs were similar, there were significant differences in certain amino acids, minerals, and fatty acid compositions. Red silk silkworm (RS)-SMSP had higher contents of crude proteins and total amino acids than other SMSPs. In addition, the ratio of n-3/ n-6 unsaturated fatty acids were higher than the other SMSPs. In contrast Golden silk silkworm (GS)-SMSP had higher ratio of potassium/sodium than the other SMSPs. These nutrient analysis results suggested that 3 SMSPs might have common and unique health improvement effects. Thus, further studies in the functionalities of the 3 SMSPs will reveal unknown their health improvements effects.

Comparative analysis of physico-chemical properties and amino acids profile of three tropical maize hybrid cultivars in Nigeria

Purpose The purpose of this study was to compare the physico-chemical properties and amino acid profile of three maize hybrid cultivars grown in Nigeria. Design/methodology/approach Two normal maize endosperm varieties, yellow SUWAN-ISR (YNM) and white ART/98/SW05-OB-WC (WNM), and one yellow QPM variety, TZE-POP-DT-STR-QPM (YQPM), were selected for the study. Physico-chemical properties, physical tests, proximate composition analysis, functional properties and characteristics and amino acid profile tests were carried out on the grains using standard methods. Findings Protein was significantly higher (p < 0.05) in YQPM (10.49 per cent) than in normal endosperm, YNM (8.83 per cent) and WNM (8.50 per cent). Amino acid profile of the grains revealed that total amino acid of YQPM (94.67 g/100 g of protein) and essential amino acid of YQPM (39.070) were the highest among the three, with highest significantly different value of tryptophan (0.388 g/100 g of protein) at p < 0.05. The cooking quality of YQPM was found to be better than the other two, with highest hydration capacity and increase in volume after cooking (90.8 ± 0.01 g/1000 grains and 147.53 ± 0.02 per cent). Originality/value YQPM will be highly beneficial in the tropics, where maize is grown as the major staple food to reduce hunger and malnutrition because of its amino acid balance and its better cooking quality.

Assessment of nutritional quality of water hyacinth leaf protein concentrate

This study was embarked upon to convert water hyacinth, an environmental nuisance, to a natural resource for economic development. Water hyacinth leaf protein concentrate (WHLPC) was extracted in edible form and determination of its physicochemical characteristics, total alkaloids and phenolic compounds was done. Analysis of proximate composition and amino acid profile of the WHLPC was also done. The level of heavy metals (mg/kg) in WHLPC was found to be Cd (0.02±0.001), Cr (0.13±0.001), Pd (0.003±0.001) and Hg (0.02±0.001) while concentrations of Pb, Pt, Sn, Fe, Cu, Zn, Ni and Co were found to be 0.001±0.00. Level of all heavy metals was found to be within safe limit. Proximate analysis revealed that protein in WHLPC accounted for 50% of its nutrients, carbohydrate accounted for 33% of its nutrients while fat, ash and fibre made up the remaining nutrients. Amino acid analysis showed that WHLPC contained 17 out of 20 common amino acids, particularly, Phe (3.67%), Leu (5.01%). Level of total alkaloids and phenolic compounds was 16.6mg/kg and 6.0mg/kg respectively. Evidence from this study suggests that WHLPC is a good source of leaf protein concentrate (LPC); it is nutritious and acutely non toxic.

Monthly variation in the proximate composition of jack mackerel (Trachurus japonicus) from Geumo Island, Korea

Proximate analysis for proportions of lipids, proteins, ash, and water contents of fish tissue provides a powerful insight to obtain physiological information for the fish population being studied. In this study, the proximate compositions for the jack mackerel (Trachurus japonicus) caught in Geumo Island, Korea known as a nursery ground were examined monthly in 2013 and 2014. No significant seasonal variation was found in protein and ash contents whereas a strong seasonal variation was found in water and lipid contents. The lipid contents showed relatively higher values ranging from 3.94% to 5.75% in summer and fall which corresponds to their active feeding periods. A strong inverse relationship was found between the lipid and water contents (n=16, r=−0.859, p<0.01). The water contents was significantly (t-test, p<0.01) higher in the early period from May to August in 2014 than in 2013, which was probably caused by the smaller fork lengths on May and June in 2014. The overall lipids, proteins, ash, and water contents of jack mackerel were 3.71, 21.41, 3.65, and 68.90%, respectively, which was significantly different from the results reported previously for jack mackerel. Mainly three major factors were suggested for the difference. The first one is the different body sizes of jack mackerel since growing fish accumulate lipids in their bodies as they feed more prey. The different methods for the proximate composition analysis might be another reason. In general, the whole fish analysis had lower water contents and higher ash contents than only fish fillet analysis. The other reason might be different sampling regions and times. A long term monitoring for the physiological status of early stage jack mackerel is expected to provide necessary information for the successful management of this fish stock.

Proximate composition and elemental analysis in soft tissues of freshwater mussels (Anodonta anatina) from the Chashma Lake, River Indus Pakistan

Aquatic invertebrates are playing an important role in assessment of the water contaminants and also serve as a major component of food chain. Freshwater mussels are considered to be the good bioindicator species of aquatic environment and widely used to determine the metals load. Proximate composition and elemental analysis were carried out in edible (foot, mantle) and non-edible portion (gills) of freshwater mussels (Anodonta anatina) harvested from various site of Chashma Lake, River Indus Pakistan. The nutritional components were varied among the studied portion and muscular foot found to be the best part for consumption. Protein and fat contents were significantly higher in foot (15.90±0.88%, 1.19±0.26%) as compared to mantle (10.78±2.24%, 0.27±0.09%) and gills (6.44±1.22%, 0.53±0.15%) respectively. For the macro minerals mantle had high concentration of Ca (46838±984 mg/kg), Na (2706±343 mg/kg), P (6921±1063 mg/kg) and Mn (7207±1046 mg/kg) as compared to foot. Heavy metals (Cd, Cu, Cr) concentration in edible portions were lower than the permissible limit by WHO whereas the concentration of Pb was slightly higher than the recommended value that might be the risk for the consumers. Being filter feeder gills accumulated the high concentration of all the metals and found to be the key portion for biomonitoring studies. Freshwater mussels of Chashma Lake Indus River are the rich source of protein and all the other micro and macro minerals therefore could be used as an excellent source of food.

Nutritional and bioactive compounds composition ofEulepida mashona, an edible beetle in Zimbabwe

Eulepida mashona Arrow (Coleoptera: Scarabaeidae) is widely consumed in rural and farming communities ofZimbabwe. Preparation methods before consumption for these insects are variable and have not been documented. Our study hypothesised that cooking for different durations result in different nutritional and bioactive compoundscomposition in insects and significant losses of beneficial bioactive compounds. Representative samples derivedfrom standard insect sampling procedures were collected from natural occurrences in Mashonaland West Province, Zimbabwe. Proximate composition and bioactive component analyses were conducted following standard proceduresusing dried pulverised material from whole insects. There were no significant differences in proximate componentsbetween dried uncooked and cooked insects. Both insect samples prepared differently showed high crude protein and fibre contents of 62.4 and 25.4%, respectively, on dry matter basis; values which were higher than those of mostsimilarly handled edible insects in southern Africa. In dried uncooked insects flavonoids occurred in quantitiesof 0.024 mg/g. Relative to other compounds tested, saponins and oxalates occurred in higher quantities, that is, 196 and 28 mg/g, respectively, on dry matter basis. These two components were reduced by factors of 12 and 1.4, respectively, when insects were cooked for 30 minutes and dried. Cyanogen glycosides content was reduced three fold (from 1.4 to 0.43 μg/g) when insects were cooked for 30 minutes. However, safety concerns of hydrogen cyanideexposure exist, also in cases where smaller quantities (&lt;50 g dry weight) of insects are consumed. Studies are neededon adequate processing to reduce risk of toxicity from cyanogen compounds. In general, cooking insects for 30minutes resulted in significant reduction of potentially harmful bioactive compounds namely: alkaloids, cyanogen glycosides, oxalates, tannins and saponins. There is high potential for exploitation ofE. mashona as an additional commercial source of protein and fibre if consumer safety concerns are addressed.

Influence of natural and synthetic carotenoids on the color of egg yolk

Carotenoids are incorporated into the diet of laying hens in order to modify the yolk color. A natural source of carotenoids in tropical countries is annatto, which could be used in the diets of hens. This study aimed to evaluate the addition of natural (annatto) and synthetic carotenoids to the diet of laying hens (commercial and alternative) and their effects on yolk color and consumer sensory perception of fresh and stored eggs obtained from two different preparations (boiled and fried). Physicochemical analysis of proximate composition, thiobarbituric acid reactive substances (TBARS), emulsion activity and instrumental color were performed. Cooking caused significant alterations to the moisture in the preparations and this may have directly affected the color intensity, influencing factors related to egg appearance. In this study, 85 % of the panelists indicated that yolk color is an important attribute of the product’s quality. There was no antioxidant effect of the carotenoids in raw eggs. Synthetic additives should be better dosed to obtain the desired effect. Storage did not alter the proximate composition of the eggs.

Composition of broilers meat

SUMMARY Brazil stands out in the ranking of broiler chicken production, holding the positions of the world's largest exporter and the third largest producer, scores that demand continuous attention to market requirements with regard to product quality, including the search for alternative sources of feed ingredients. This research's goal was to examine the effects of using Rubrivivax gelatinosus biomass in the feed of broilers on proximate composition, cholesterol content, and fatty acid profile of the meat cuts. Two hundred Cobb 500 male chicks were randomly assigned to one of the 4 dietary treatments containing zero, one, 2 or 3 g of dried R. gelatinosus biomass per kg of the finisher ration. At the end of the experiment, 20 birds from each treatment were slaughtered and their carcasses were cut into breast and thigh for the analyses of proximate composition, cholesterol, and fatty acids, all performed by standard methodologies. Data were analyzed by ANOVA and t test for the multiple comparisons of means using 5% of significance. Proximate composition and cholesterol concentration in both breast and thigh meats did not differ among treatments (P > 0.05). The biomass at 3 g/kg in the diet increased EPA in breast but decreased it in thigh. Nevertheless, no concentration of the biomass altered the ratio n-6/n-3 in either cut. Thus, the use of R. gelatinosus biomass at 3 g/kg in broilers’ rations was shown to be harmless or even beneficial to broiler meat composition.

Production of bioethanol by bacterial co-culture from agro-waste-impacted soil through simultaneous saccharification and co-fermentation of steam-exploded bagasse

The production of bioethanol by co-culture of cellulolytic and xylanolytic bacteria isolated from agro-waste-impacted soil through simultaneous saccharification and co-fermentation (SSCF) of steam-exploded bagasse was investigated. The cellulolytic (VCE-19) and xylanolytic (VXE-41) isolates were screened using the Congo Red Plate Method. The DNS method was used in the determination of reducing sugar content. Chemical analysis of the sugarcane bagasse was determined using standard methods. The bagasse was subjected to steam explosion to reduce lignin content and enhance cellulose availability. Mean proximate composition analysis of the bagasse showed total carbohydrate and lignin content (% dry weight) of 70.3 ± 1.9 and 19.2 ± 1.2 before pretreatment and 85.4 ± 2.33 and 4.2 ± 0.44 after pretreatment, respectively. Phylogenetic analysis based on partial sequence of the 16S rRNA gene classified VCE-19 and VXE-41 as Bacillus cereus GBPS9 and Bacillus thuringiensis serovar kurstaki HD1, respectively. The sequences obtained from these isolates have been submitted to GenBank and accession numbers (KT350986.1 for VXE-41 and KT318371.1 for VCE-19) assigned to them. The result of the optimization of cultural conditions of the bacterial co-culture revealed optimum cellulase production at the following conditions: temperature, 40 °C; pH, 7; substrate concentration, 4.0 % (w/v); inoculum concentration, 4 % (v/v) and when yeast extract was used as nitrogen source. The gas chromatography–mass spectrometry (GC–MS) analysis of the fermentation broth detected the following components: acetone (3.49 g/L), ethylacetate (8.75 g/L), ethanol (19.08 g/L), N-propanol (4.96 g/L), isobutanol (3.73 g/L) and acetic acid (6.53 g/L). This study has demonstrated the production of significant quantity of ethanol by a co-culture of B. cereus GBPS9 and B. thuringiensis serovar kurstaki HD1 through SSCF of steam-exploded bagasse. Efficient bioethanol production from bagasse can help solve the need for alternative source of energy and the crisis that results from bioethanol production from food and feed crops.

Enrichment of Food Mixtures with Essential Fatty Acids and Calcium from Nile Tilapia By-Products

ABSTRACTThis work aimed at increasing the content of calcium and the quality of fatty acid composition of food mixtures developed with by-products from Nile tilapia fed with flaxseed. Mixes using cassava flour and by-products were submitted to analyses of proximate composition, fatty acids and minerals quantification, and sensory assessment. The lipid and protein fractions were higher for the mix containing 30% addition of fish meal. There was an incorporation effect of essential fatty acids in the mix of flours containing fish fed with flaxseed. Calcium had the highest concentration among minerals. Sensory acceptance range was 55–65% for formulations with fish by-products.

Detoxification of Olive Mill Wastewater and Bioconversion of Olive Crop Residues into High-Value-Added Biomass by the Choice Edible Mushroom Hericium erinaceus.

Environmentally acceptable disposal of olive cultivation residues (e.g., olive prunings; olive pruning residues (OLPR)) and olive mill wastes is of paramount importance since they are generated in huge quantities within a short time. Moreover, olive mill wastewater (OMW) or sludge-like effluents ("alperujo"; two-phase olive mill waste (TPOMW)) are highly biotoxic. Hericium erinaceus is a white-rot fungus which produces choice edible mushrooms on substrates rich in lignocellulosics, and its suitability for the treatment of olive by-products was examined for the first time. Fungal growth resulted in a notable reduction of OMW's pollution parameters (i.e., 65% decolorization, 47% total phenolic reduction, and 52% phytotoxicity decrease) and correlated with laccase and manganese peroxidase activities. Solid-state fermentation of various mixtures of OLPR, TPOMW, and beech sawdust (control) by H. erinaceus qualified OLPR in subsequent cultivation experiments, where it exhibited high mushroom yields and biological efficiency (31%). Analyses of proximate composition and bioactive compound content revealed that mushrooms deriving from OLPR substrates showed significantly higher crude fat, total glucan, β-glucan, total phenolics, and ferric-reducing antioxidant potential values than the control. H. erinaceus demonstrated the potential to detoxify OMW and bioconvert OLPR into high-quality biomass, and hence, this fungus could be successfully exploited for the treatment of such by-products.

Morphological divergence in Indian oil sardine, Sardinella longiceps Valenciennes, 1847- Does it imply adaptive variation?

The Indian oil sardine, Sardinella longiceps, is an important pelagic species in Indian waters, and shows divergent morphology while in sympatry. The reasons behind this divergent morphology were investigated using morphometric, genetic and nutritional analyses. Twenty-one morphometric characters (as percentage of standard length) and eight meristic characters were studied in the three variants to assess whether they are significantly diverged. Distinct clustering of morphotypes was evident in the principal component analysis on log-transformed ratios of morphological characters with PC1 and PC2, explaining 50.7% and 17.6% of the total morphological variation, respectively. PC1 was highly correlated with the distance from snout to anal origin, depth at dorsal, distance from snout to pelvic and distance from snout to first dorsal. PC2 was highly correlated with head length, caudal width and anal depth. Analysis of similarities (ANOSIM) was conducted using log-transformed morphometric ratios, with the results showing the clusters to be well differentiated (R = 0.511; P < 0.01). Similarity of percentage analysis (SIMPER) analysis showed that the differences in depth at the dorsal, anal base length, caudal width, distance from pelvic to anal origin, anal depth and eye diameter accounted for 52% of variations between variant 1 and 2. Differences in caudal width, distance from pelvic to anal origin, anal base length, depth at dorsal and anal depth accounted for 56% of the variation between variant 2 and 3. Differences in caudal width, eye diameter, anal base length, anal depth, distance from pelvic to anal origin accounted for 50% of the variation between variant 1 and 3. Genetic divergence was not significantly based on mitochondrial cytochrome c oxidase I (COI) or control region sequences. Proximate composition analyses showed significantly high fat content in variants 1&3 and significantly high protein content in variant 2, probably due to dissimilar dietary preferences. The study shows that morphotypes of the Indian oil sardine may be the result of divergent selection and adaptive variations, which need further investigation using a long-term sampling design.

Differences in meat colour between free-range Swallow Belly Mangalitsa and commercially reared Swedish Landrace pigs during 6 days of vacuum storage

Abstract. The influence of storage on meat colour differences between free-range Swallow Belly Mangalitsa (MA, n = 19) and commercially reared Swedish Landrace (SL, n = 17) pigs, are investigated in the present study. Proximate composition analyses were done on fresh samples of M. longissimus thoracis (LT) and M. gluteus medius (GM), while pH values and colour quality attributes were determined on fresh cuts of the muscles (day 1) and after 3 and 6 days of vacuum storage at 4 ± 1 °C. MA pork had a significantly higher share of intramuscular fat, a darker colour, a higher deoxymyoglobin (Mb) content and oxy ∕ met (oxymyoglobin ∕ metmyoglobin) ratio, higher pH24 h values and a slower pH decline compared to the control SL group (P &lt; 0.05). Greater changes in myoglobin forms during storage were observed in MA pork, which were reflected in a significant decrease in the content of Mb and an increase in the oxy ∕ met ratio (P &lt; 0.05).After 6 days of vacuum storage, higher pH6d values, a lower metmyoglobin (MetMb) content and a higher oxy ∕ met ratio of MA pork lead to the conclusion that aged meat from free-range Swallow Belly Mangalitsa pigs had better colour quality compared to Swedish Landrace pigs.

돈피 젤라틴을 첨가한 유화형 소시지의 이화학적 특성 연구

본 연구는 돈피 젤라틴 첨가에 따른 유화형 소시지의 이화학적 특성을 조사하였다. 처리구별로 유화형 소시지 제조 시 젤라틴 함량을 0%, 1%, 3%, 5%를 첨가하여 제조하였다. 일반성분 측정 결과 수분 함량은 대조구에 비해 젤라틴 3%와 5% 첨가구가 유의적으로 높았으며(P0.05), 단백질 함량은 젤라틴 5% 첨가구가 대조구와 젤라틴 1% 첨가구보다 유의적으로 높은 결과를 나타내었다(P0.05). 또한 지방은 감소하는 경향을 보였으나 유의적인 차이는 없었다. pH는 가열 전후 모두 젤라틴 첨가 함량이 증가할수록 유의적으로 증가하였다(P0.05). 색도 측정 결과 가열 전 적색도와 황색도는 처리구 간에 유의적인 차이가 없었으며, 명도는 젤라틴 첨가구가 유의적으로 높은 값을 나타내었다(P0.05). 가열 후 명도와 황색도는 젤라틴 첨가구가 대조구에 비해 유의적으로 높은 값을 나타내었으며(P0.05), 적색도는 젤라틴 3%, 5% 첨가구가 낮은 값을 나타내었다(P0.05). 보수력은 대조구가 젤라틴 첨가구보다 유의적으로 낮았으며(P0.05), 젤라틴 3%와 5% 첨가구가 유의적으로 높은 값을 나타내었다(P0.05). 가열수율은 젤라틴 첨가량이 증가할수록 유의적으로 높아졌다(P0.05). 점도는 젤라틴 3%와 5% 첨가구가 대조구와 1% 첨가구보다 유의적으로 높았다(P0.05). 물성 측정 결과 탄력성, 응집성, 씹힘성은 대조구와 처리구간에 유의적인 차이를 보이지 않았다. 경도는 대조구와 젤라틴 1% 첨가구가 다른 처리구에 비해 유의적으로 낮았으며 (P0.05), 젤라틴 5% 첨가구가 가장 높은 값을 나타내었다. 또한 검성은 젤라틴 5% 첨가구가 대조구에 비해 유의적으로 높은 값을 나타내었다(P0.05). 이러한 결과로 보아 유화형 소시지에 젤라틴 첨가 시 이화학적 특성을 우수하게 변화시키는 것으로 나타내어 향후 다양한 소시지형 제품에 기능성 소재로 활용할 가능성이 있을 것으로 판단된다.

Phytopreventive antihypercholesterolmic and antilipidemic perspectives of zedoary (Curcuma Zedoaria Roscoe.) herbal tea.

BackgroundMetabolic syndrome is an increasingly prevalent problem, not only in industrialized developed countries, but in developing countries as well. The modern healthcare to reduce the dysfunction of metabolic syndrome is burdened with great problems of unsafe medicines and certain degree of side effects. Medicinal plants and derived component products are becoming increasingly popular in modern society as natural alternatives to synthetic multiple drugs for the treatment of hypercholesterolemia and hypertriglyceridemia. The present research work was carried out to evaluate the zedoary (Curcuma zedoaria Roscoe.) herbal tea (ZHT) for antihypercholestrolemic and antilipidemic perspectives in discerning consumers.MethodsZedoary rhizome dried powder (ZRDP) after proximate composition analysis was used to prepared ZHT samples as T1 (500 mg ZRDP), T2 (1 g ZRDP) and T3 (1.5 g ZRDP) in 200 mL boiling water for 5 minutes, respectively. ZHT samples were characterized for total phenolic compounds (TPC), DPPH inhibition, total flavonoids, color tonality (L*, a* and b* value), pH, acidity, total soluble solids (TSS) and sensory acceptance. Thirty mild–hypercholestrolemic male human volunteers were randomly allocated to three groups (G1, G2 and G3) and each group consisting of 1o mild–hypercholestrolemic male human subjects. The volunteers were assigned ZHT samples for consecutive two months. The blood drawn for day 0, day 30 and day 60 after an overnight 12 h fast was analyzed for serum parameters such as total cholesterol (TC), high–density lipoprotein cholesterol (HDL–cholesterol), low–density lipoprotein cholesterol (LDL–cholesterol) and triglycerides (TG) concentration.ResultsThe ZRDP possessed abundantly the crude protein (13.5 ± 0.68 %), total dietary fiber (21.86 ± 0.71 %), acid detergent fiber (13.22 ± 0.44 %), neutral detergent fiber (18.68 ± 0.53 %) and mineral contents. Highest TPC, DPPH inhibition and total flavonoids values were observed 9.74 ± 0.64 (mg GAE/g DW), 47.28 ± 1.62 (%) and 17.12 ± 0.75 (QE mg/g), respectively in T3. L* value was significantly (p ≤ 0.05) low for T3 samples. In contrast, a* value and b* value was significantly (p ≤ 0.05) higher for T3 when compared with T1 and T2. T3 samples showed lower pH (5.13 ± 0.13) and higher acidity (0.25 ± 0.08) values than T1 (5.64 ± 0.25, 0.17 ± 0.05) and T2 (5.42 ± 0.21, 0.21 ± 0.06), respectively. Similarly, an increasing trend in TSS contents was observed. Sensory scores assigned to color, flavor, aroma and overall acceptability attributes varied in a quite narrow range for all ZHT samples. The lowest evaluation scores were recorded for T3 samples. The G3 showed the more reduction in body weight and BMI during efficacy study as compared to G1 and G2. The decrease in serum TC for G1, G2 and G3 on day 60 was observed 9 %, 14 % and 17 %, respectively when compared with reference value at day 0. The consumption of T3 resulted in significant increase (6.8 %) of HDL-cholesterol after two months. A trend in decrease of serum LDL–cholesterol (5.6 %) and TG (12.5 %) was also observed after consumption of T3 at day 60.ConclusionsThe results of the present study conclude that the strong phenolic contents and radical scavenging activity of zedoary rhizome have protective role against hypercholesterolemic and lipidemic conditions.

Nursery performance of Pacific white shrimp (Litopenaeus vannamei Boone, 1931) cultivated in a biofloc system: the effect of adding different carbon sources

Effect of different carbon sources on nursery performance of Pacific white shrimp (Litopenaeus vannamei) cultivated in biofloc system was investigated. Shrimp postlarvae (98.47 ± 8.6 mg) were fed for 32 days in tanks with water volume of 130 L and density of 1 individual L−1. One control treatment and four biofloc treatments (BFT1, BFT2, BFT3 and BFT4) with adding different carbon sources including molasses, starch, wheat flour and mixture of them, respectively, were considered at equal weight ratios. According to the results, salinity, dissolved oxygen and pH were not significantly different among the biofloc treatments (P > 0.05). Maximum pH (8.27) and maximum dissolved oxygen (6.35 mg L−1) were recorded in the control. Maximum (0.43 mg L−1) and minimum (0.09 mg L−1) ammonia were recorded in the control and BFT2, respectively (P < 0.05). Using simple carbohydrates (molasses and starch) lowered the ammonia concentration significantly. The highest increase in body weight (1640.43 ± 231.28 mg), growth rate, specific growth rate (8.97 ± 0.42% per day) and biomass (190.29 ± 26.83 mg) were found in BFT1 and the highest survival (90 ± 0.77%) was found in BFT4. The highest feed conversion (1.52 ± 0.23) and the lowest feed efficiency (66.81 ± 7.95) were observed in the control (P < 0.05). The proximate composition analysis revealed an increase in lipid and ash in biofloc treatments. Results indicated that using biofloc technology with zero-water exchange system and adding carbon sources could help to recycle waste and improve the water quality. Moreover, the type of carbonaceous organic matter as a substrate for heterotrophic bacteria would be effective in degradation and metabolization of ammonia and nitrite.

Assessment of quality and safety of traditional smoked spotted tilapia fish (Tilapia mariae) from Lagos State, Nigeria

Purpose – This study aims to assess the quality and microbial safety of traditional smoked spotted tilapia fish from Lagos State and, by doing so, determine the quality and microbial safety level of traditional smoked spotted tilapia fish, their distribution, effects and possible public health implications of the quality/rancidity indices and microorganisms on the consumers. Design/methodology/approach – Fresh spotted tilapia fish (100 samples) were collected from 20 different fishing/processing centres and divided into two batches. One batch was smoked with local drum kiln at processing centres, and the second batch was smoked with convective smoking kiln as control in the laboratory. Each batch was assessed for moisture content, protein content, fat content, crude fibre content, ash content, pH, thiobarbituric acid (TBA), total volatile base- nitrogen (TVB-N), trimethylamine (TMA), peroxide value (PV) and free fatty acid (FFA) values. Microbiological analyses were also conducted. Each batch was assessed for total viable count (TVC), fungal count, Listeria monocytogenes count, Staphylococcus aureus count, Salmonella paratyphi count and presence or absence of Escherichia coli. Findings – The results of the proximate composition, quality indices and microbiological analyses revealed that there was significant variations (p &lt; 0.05) between smoked fish with different smoking methods. The mean pH, TBA, TVB-N, TMA, PV and FFA values of fresh and smoked spotted tilapia fish samples were within the range recommended by United States Food and Drug Administration. The mean TVC of fresh spotted tilapia fish samples was 6.3 × 106-8.8 × 108 cfu/g and TVC of samples of smoked spotted tilapia fish and the control were 2.0 × 104-6.4 × 104 cfu/g and 1.0 × 103-8.6 × 103 cfu/g, respectively. The mean L. monocytogenes count of fresh spotted tilapia fish samples was 1.3 × 102-2.4 × 102 cfu/g and that of samples of smoked spotted tilapia fish ranged from 1.6 × 101 to 23.1 × 101 cfu/g while samples of smoked spotted tilapia fish using convective smoking kiln showed no count for L. monocytogenes. The mean S. aureus count of fresh spotted tilapia fish samples ranged from 4.7 × 103 to 8.0 × 103 cfu/g and that of samples of smoked spotted tilapia fish ranged from 5.1 × 102 to 88.6 × 102 cfu/g and 1.1 × 102 to 3.8 × 102 cfu/g. The mean fat content (FC) count of samples of smoked spotted tilapia fish ranged from 1.1 × 101 to 6.0 × 101 cfu/g. S. paratyphi and E. coli were not detected in all smoked spotted tilapia fish samples. The study, however, concluded that the traditional drum smoked spotted tilapia fish could expose consumers to high microbial risk because of the presence of L. monocytogenes. Research limitations/implications – The fresh fish used in this study were obtained from coastal villages in Lagos State, and there were limitations in getting the samples in time to the processing centres and in preserving the fresh fish because of poor or non-availability of power (electricity). Practical implications – The paper includes implications for the development of a cost-effective smoked fish, to ensure food safety, enhanced health and improve the preservation and post-harvest losses of fresh fish. Social implications – The paper helps in developing an effective smoked method that will produce good-quality smoked fish, reduce the incidence of food poison and enhance the health of consumers. Originality/value – This research is of value to the traditional fish smokers and consumers. Smoked fish has been implicated as a source of microbial infection in Nigeria and West African sub-region in recent times and the need for good manufacturing practices cannot be overemphasized.

Proximate composition and heavy metal analyses of commercial fish feeds in Nigeria

Fingerling, juvenile and grower fish feeds (imported and locally produced) were obtained and proximate analysis was done to determine moisture content, ash content, crude fibre content, crude fat content, crude protein content and carbohydrate content. Results revealed that locally grower (LG) feed have higher moisture and carbohydrate content and the least crude protein and fat content. According to the results obtained, glutamic acid was the most abundant followed by aspartic acid, leucine, arginine, phenylalanine, lysine, valine and proline. All the amino acid content of Imported fingerling (IF) and juvenile (IJ) feeds are higher than the amino acid content of Imported and local grower (IG, LG) feeds. . Mineral content in increasing order of all the samples in mg/kg of feeds are as follows: Fe (67.20 - 93.99): IG &gt;IF&gt;LG&gt;IJ; Cu (8.29 – 13.61): IJ&gt;IG&gt;IF&gt;LG; Mn (48.02 –82.78): IJ&gt;LG&gt;IG&gt;IF; Zn (122.30 – 146.27): IF&gt;IJ=IG&gt;LG; Se (0.227 – 0.672): LG&gt;IF&gt;IG&gt;IJ; Cr (0.457 – 1.120): LG&gt;IF&gt;IJ&gt;IG; Cd (0.224 – 0.490): IF&gt;IJ&gt;LG (IGND); Ni (0.229 – 0.245): LG&gt;IF&gt;IG (IJ- ND). Cobolt was not detected in all the feeds while 1.12 mg/kg feeds Lead was detected in locally produced grower feed only.Key words: Fish-feed, proximate analysis, amino-acid, mineral content, statistical analysis

Acceptability of reformulated whole-grain products using net acceptance score (NAS) and relative acceptance score (RAS)

Objectives: (1) To determine the proximate composition and sensory qualities of three traditional, commonly consumed Omani grain products (samoon, khubs, and rekhal), while replacing refined refined-wheat flour by whole wheat flour at three levels (0%, 50%, and 100%). (2) To develop the Net Acceptance Score (NAS) and Relative Acceptance Score (RAS) based on the Net Promoter Score (NPS) using sensory evaluation results. Materials and Methods: Samoon, khubs, and rekhal were reformulated with whole wheat flour at three levels: (i) RF100 (refined flour 100%, control), (ii) RF50 WWF50 (refined flour 50% + whole wheat flour 50%), and iii) WWF100 (whole wheat flour 100%). Proximate composition analysis and sensory evaluation [using the hedonic scale (9–1)] were conducted for each product type. The hedonic scores received from the panelists were then used to calculate the Net Acceptance Score (NAS) and the Relative Acceptance Score (RAS). The NAS is an indicator of the net acceptability of an individual product, whereas RAS is the relative acceptability of the reformulated product with respect to the control product. Results: Among all three product types, NAS of taste was the highest for WWF100. The NAS values of the taste attribute for WWF100 were 42%, 73%, and 16% for rekhal, khubs, and samoon, respectively. Both RF50 WWF50 and WWF100 rekhal products yielded the RAS value of 100%.

Effects of Dietary Lecithin, Nucleoside, and Krill Supplementation to a Fishmeal Based Diet on Growth and Feed Utilization of Sharpsnout Sea Bream (Diplodus Puntazzo)

The aim of this 96 day feeding trial was to investigate the effects of the addition of different combinations of dietary lecithin, nucleosides, and krill to a fishmeal-based diet on the growth, feed utilization, feed consumption, and body composition of sharpsnout sea bream (Diplodus puntazzo). Six hundred (600) fish (average weight 21.21 ± 0.06SD g) were divided into 8 groups (triplicate treatments) and fed eight isoenergetic fishmeal-based diets, (C-control, L-lecithin, N-nucleosides, K-krill, L+N-lecithin+nucleosides, N+K-nucleosides+krill, L+K-lecithin+krill, L+N+K-lecithin+nucleosides+krill). The effects of the dietary regimes were evaluated in terms of specific growth rate (SGR), feed conversion ratio (FCR), daily feed intake (DFI), and whole body chemical composition (moisture, crude ash, crude protein and crude lipid). At the end the trial the fish had tripled their initial weight. SGR, FCR and DFI were 1.17-1.24 %, 0.95-1.01, and 1.03-1.14% respectively. Although differences were observed between some groups, none of the tested feed additives improved SGR, FCR, and DFI, compared to the control diet. Analysis of whole body proximate composition showed that moisture, crude ash, crude protein, and crude lipid ranged 61.45-64.00%, 3.96-4.26%, 15.44-17.26% and 14.87-18.82% respectively. Crude lipid concentration was higher in whole body of fish fed the nucleoside supplemented diet compared to control, lecithin, and krill groups. No other effects of the dietary regime on the whole body composition of sharpshout sea bream were observed.