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The purpose of this paper is to prepare poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by two different routes. In the first route, poly(allyl amine-ran-acrylic acid)s were produced by radical copolymerization of a mixture of ally amine and acrylic acid, then converted into poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by the Mannich reaction with a mixture of formaldehyde and phosphonic acid. In the second route, allyl amino bis(methylene phosphonic acid) monomer was synthesized and copolymerised with acrylic acid. The aim of this work is to produce low-molecular-weight copolymer with the low amount of nitrogen and phosphorous having better scale inhibiting performance than commercial low-molecular-weight poly(acrylic acid)s.

Poly(allyl amine-ran-acrylic acid)s were prepared by radical copolymerisation of a mixture of ally amine and acrylic acid, and the molecular weight of copolymers was regulated by using an effective chain transfer compound and the formed copolymer was reacted with a mixture of formaldehyde and phosphorous acid. Allyl amino bis(methylene phosphonic acid) monomer was prepared and then copolymerised with acrylic acid using radical initiators.

Poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] produced with both routes, especially low-molecular weight ones have better anti-scaling performance than low-molecular-weight commercial poly(acrylic acid).

By using an excess of formaldehyde and phosphonic acid, a limited increase in the conversion of amine groups of poly(allyl amine-ran-acrylic acid) to amino methylene phosphonic acid groups was achieved, so unreacted amine groups were always present in the structure of the final copolymers.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] may be used as a better anti-scaling polymer in industry.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] is an alternative polymer for scale inhibition in the water boilers.

The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] copolymers containing both carboxylic acid and amino bis(methylene phosphonic acid) are more effective anti-scaling additives than poly(acrylic acid)s in water boilers.

This study was aimed to estimate and compare the contents of protein and amino acids in raw, boiled and fried fishes of Indian mackerel “kembong” (Rastrelliger kanagurta), sardine (Sardina pilchardus), red tilapia (Oreochromis mossambicusx) and black tilapia (Oreochromis mossambicus). Protein contents of raw mackerel, sardine, red and black tilapia were 8.1±0.0, 8.4±0.1, 9.6±0.4 and 9.0±0.0 percent, respectively. In a boiled fish, the protein contents were 7.9±0.1, 7.7±0.0, 7.5±0.1 and 8.9±0.1 percent, respectively, and for a fried fish the values were 8.6±0.5, 8.9±0.1, 9.1±0.2 and 8.4±0.0 percent, respectively. It was found that there was a significant difference (p<0.01) in the protein content of the raw fish compared to the heat‐treated ones for all the fishes. The study detected 17 components of essential amino acids (lysine, histidine, threonine, valine, methionine, leucine, isoleucine and phenylalanine) and non‐essential amino acids (arginine, aspartic acid, serine, glutamic acid, proline, glycine, alanine, cystein and tyrosine) in all the fishes. There was no significant difference in amino acids content among the boiled and fried fishes. In conclusion, heat treatment for five minutes in boiling water (100°C) and frying for three minutes in palm oil (160°C) did not alter the quality of protein in all the fishes studied.

In line with current research efforts to develop eco-friendly strategies for corrosion mitigation, the purpose of this study is to appraise the anti-corrosion potential of selected amino acids on magnesium corrosion in sodium chloride solutions.

The corrosion inhibition of magnesium in aqueous solutions in the presence of benign, eco-friendly and readily available amino acids (alanine, arginine, histidine, lysine, proline) were evaluated using electrochemical methods.

Amino acids suppressed magnesium corrosion rate in aqueous sodium chloride solutions. The order of inhibition efficiency (%IE) was as follows: alanine < arginine < histidine < lysine < proline. The open circuit potential shift with respect to the blank was less than 0.085 V_SCE, indicating that the amino acids are mixed-type corrosion inhibitors. In addition, the %IE of the amino acids was inversely proportional to the molecular weight. The results obtained indicate that the amino acids can serve as sustainable eco-friendly corrosion inhibitors for magnesium with the best inhibition efficiency attributed to proline with an efficiency of 85.1%.

New information on the application of amino acids as green sustainable corrosion inhibitors is provided herein.

The purpose of this study was to isolate Whitemouth croaker protein by alkaline solubilization process and evaluate their nutritional quality to evaluate the bioavailability of essential amino acids.

The proximate composition, essential amino acid composition, in vitro digestibility, apparent bioavailability, chemical score of amino acids and SDS-PAGE were determined for the isolated croaker proteins.

The isolated protein showed a high level of protein 92.21 percent and low amount of lipids 0.57 percent. The protein is rich in lysine and leucine, 108.73 and 96.75 mg/g protein, respectively. The protein isolate had high digestibility, 94.32 percent, which indicates proper utilization of this protein source, while the tryptophan had lower bioavailability (12.58 mg amino acid/mg protein). The high chemical scores were found for the amino acids lysine, methionine+cysteine (6.79 and 5.14). SDS-PAGE of proteins extracted showed appearance of the heavy chain of myosin (220 kDa), actin (50 kDa) and other fractions, with molecular weight between 20 and 50 kDa, such as troponin I, C and T.

The products obtained from croaker muscle can be incorporated as a high value supplements in human diets. The isolated protein exhibited a high content of essential amino acids and digestibility, indicating that the protein has a high nutritional quality.

The purpose of the paper is to study the effects of cooking on proximate composition, amino acids, fatty acids, minerals and total, heme and non‐heme iron content of camel meat.

A total of ten longissimus thoracis muscles (500 grams) were collected between the tenth and twelfth ribs of the left side. Samples were randomly collected from two to three year old camel carcasses chilled (1‐3°C) for 48 hours then stored at −20°C. The first portion was kept fresh while the second one was placed in plastic bags and cooked by immersion in a water bath at 70°C for 90 minutes. Both samples were freeze‐dried, and then ground to a homogeneous mass to be used for chemical analyses.

Cooked samples had significantly (p<0.05) higher dry matter by 27.7 per cent, protein by 31.1 per cent and fat by 22.2 per cent, but lower ash content by 8.3 per cent than the raw ones. Cooking had no significant effect on amino acid and fatty acid composition of the meat. The components of camel meat most significantly affected by cooking were macro‐ and micro‐minerals, which ranged between 13.1 and 52.5 per cent, respectively. Cooking resulted in a significant decrease in total, heme and non‐heme iron contents by 4.3, 8.7 and 4.0 per cent, respectively.

The research is restricted to camel meat but it is an exploratory study. The issue of research outcome as only longissimus thoracic muscle is another limitation. Further investigation is needed to include different muscles, temperatures, durations and cooking methods.

Amino acids and fatty acids of camel meat are not affected by cooking, while heating accelerated total and heme iron oxidation suggest camel meat to be a rich source of heme iron.

The paper is original in its findings and useful for both researchers and academics in the field of meat science.

The purpose of this study was to accelerate the fermentation process of minced mackerel fish (Scomber scombrus L.) mixed thoroughly with 20 per cent salt (w/w) and hydrolyzed by 0.2 and 0.4 per cent bromelain at 37°C.

S. scombrus L. was mixed thoroughly with 20 per cent salt (w/w) and hydrolyzed by the bromelain at levels of 0.2 and 0.4 per cent at 37°C. The physicochemical and sensory properties were evaluated after 60 and 90 days.

In a comparison of all of the aforementioned treatments, the results showed that the samples with higher bromelain levels (0.4 per cent) had higher concentrations of formal nitrogen (622 mg/100 mL) and total volatile base nitrogen (TVB-N, 0.3 g/dL) after 90 days of fermentation (p < 0.01) . The sample with 0.4 per cent bromelain showed total free amino acids content of 13.3 g/100 g after 90 days of fermentation (p < 0.01). High levels of total fatty acids (15.6 mg/100 g) were found in samples treated with 0.4 per cent bromelain and allowed to ferment for 90 days (p < 0.01). The sauce colour became significantly highly saturated (p < 0.01) with the increase in fermentation time. Chroma was significantly increased by 44 and 66 per cent in fermented sauce samples with 0.2 and 0.4 per cent bromelain during fermentation for as long as 90 days (p < 0.01). Moreover, the addition of bromelain (0.4 per cent) resulted in mackerel fish sauce that was organoleptically preferred at the end of fermentation.

The results showed that an acceptable fish sauce could be produced from mackerel fish with supplementation with 0.4 per cent of bromelain, which reduced the fermentation time to 90 days and resulted in the most satisfactory results without compromising the product quality.

The main purpose of this paper is to determine the content of amino acids, fatty acids and minerals in seven indigenous leafy vegetables (ILVs) in Ghana.

Leaves from plants growing near Kumasi were milled to a fine powder, dried to constant weight in a vacuum desiccator, and analyzed for their content of the afore‐mentioned nutrients. The plants were: Hibiscus sabdarifa, Hibiscus cannabinus, Amaranthus cruentus, Corchorus oliforius, Solanum macrocarpon, Xanthomosa sagittifolium and Vigna unguiculatus.

All seven ILVs contained a large amount of protein (15.5‐22.8 percent), which compared favorably to the essential amino acid pattern of a WHO standard. They all contained nutritionally useful amounts of α‐linolenic acid and had an omega‐6/omega‐3 ratio of 0.1‐0.9. The seven ILVs contained quantities of calcium, copper, iron, magnesium, manganese, molybdenum and zinc that could contribute significantly to satisfying an individual's need for these elements.

The presence of relatively large amounts of various nutritionally essential macro‐ and micronutrients in these seven ILVs does not necessarily mean these nutrients are bioavailable. Future research is required to determine the amounts of anti‐nutrients (e.g. protease inhibitors, chelators) in these vegetables, and the extent to which their protein, lipid and mineral constituents are digested and/or absorbed.

Since malnutrition (e.g. iron‐deficiency anemia, rickets, zinc deficiency, protein‐calorie malnutrition) is common in sub‐Saharan Africa, the information which is provided should increase awareness among agricultural and public health officials of the nutritional value of seven underappreciated and underutilized ILVs that are indigenous to Ghana and many other parts of Africa.

The purpose of this study was to compare the physico-chemical properties and amino acid profile of three maize hybrid cultivars grown in Nigeria.

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.

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).

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.

The purpose of this paper was to determine the nutritional quality of the surimi and kamaboko obtained from mechanically separated chicken meat and evaluate the bioavailability of essential amino acids found in these products.

The mechanically separated chicken meat (MSCM) was characterized by the proximate composition, and the surimi and kamaboko were characterized by in vitro digestibility, determination of chemical score of amino acids and apparent bioavailability.

The MSCM contains 68.1 ± 0.5, 12.9 ± 0.24, 18.5 ± 0.28 and 0.6 ± 0.06 per cent moisture, protein, lipids and ash, respectively. The moisture of the MSCM (surimi) was 80.45 ± 0.15 per cent, and the protein was 10.04 ± 0.21 per cent. The highest digestibility was found for the kamaboko (92.27 per cent) which was heat-treated and the lowest was for surimi (90.82 per cent). Histidine is a limiting amino acid. In this study, the surimi showed 84.69 per cent and the kamaboko presented 81.31 per cent of the minimum requirement for adults. In relation to the apparent bioavailability, there was a decrease of surimi to kamaboko of 2.52 per cent of the limiting amino acid histidine. The surimi and the kamaboko presented 76.94 and 75 per cent of the minimum requirement for adults, respectively.

The application of the surimi technology in the production of a surimi-like material from mechanically deboned chicken meat provides a new approach toward increasing its value and utilization, e.g. for the development of meat-based products and analogs, as alternative protein sources, the surimi and the kamaboko exhibited a high content of essential amino acids, indicating that the protein has a relatively high nutritional quality.

The purpose of this paper is to evaluate the proximate composition, amino acid and mineral profiles of seafood for human consumption.

A total of 21 seafood species (eight seawater, one fresh water fish, six crustacean and six mollusc species) of commercial importance were chosen and purchased from the Istanbul local fish market. The sample to amino acids analyze was prepared in accordance with the hydrolysis technique described by Waters AccQ.Tag Chemistry Package Method (HPLC). Determination of iron (Fe), sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), selenium (Se), phosphorus (P) and iodine (I) was performed with thermo electron X7 inductively coupled plasma mass spectrometry (ICP‐MS).

The lipid contents of species were found to be very low and considered as lean. The highest total amino acid values of fishes, crustaceans and molluscs were determined in John Dory, hake, red scorpion fish, spiny lobster, Norway lobster, sea snail and pecten. The mineral content of seafood species were found to be 9.3‐157.11 mg/kg Fe, 558.13‐6095.89 mg/kg Na, 253.25‐1032.29 mg/kg Mg, 125.43‐17174.76 mg/kg Ca, 0.18‐7.76 mg/kg Se, 1586.45‐5811.16 mg/kg P and 0.086‐2.630 mg/kg I.

This paper is helpful to consumers and academics concerning the proximate, amino acid and mineral composition of 21 estimable seafood species (nine fish, six crustacean and six mollusc species).