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Exploring the influence of external product attributes on consumers' perceived acceptance of pea protein as a protein substitute in food productsQuinn, Tineke 07 1900 (has links)
The purpose of this study was to explore the influence of external product attributes on
consumers’ perceived acceptance of pea protein as a protein substitute in food products.
The interest in pea protein as a possible protein source was investigated and the various
advantages of consuming pea protein were highlighted. In previous studies, pea protein
was identified as a possible substitute for red meat (Davies & Lightowler, 1998), but also
as protein containing the amino acid profile which corresponds with the profile
recommended for adults by the Food and Agriculture Organisation (FAO) (Swendseid,
1981). Additionally the nutritional and health benefits, the environmental benefits of
growing pea protein as well as the non-allergen declaration accompanying pea protein
were discussed.
The various factors that will influence the consumer’s decision making process when
introduced to a new and unfamiliar protein source such as pea protein were investigated
in terms of the external product attributes as well as the factors indicated in the Theory of
Reasoned Action (TRA) (Fishbein & Ajzen, 1975). The external product attributes were
identified as the influence of price, marketing of the product, packaging attributes of new
food products, branding importance of a product and new product education and
knowledge perceived necessary for acceptability of a new food product. The additional
factors which were investigated, as indicated by the TRA, included the influence of the
subjective norms or significant others, as well as the consumers’ personal attitude. attitude.
Due to the limited insight and understanding of the influences that external product
attributes have on a consumer’s perceived acceptance of pea protein as a protein
substitute in food products, a qualitative exploratory research design was initiated. An
exploratory research design was incorporated because this afforded the researcher the
opportunity to gather thorough and comprehensive data or information and it also
increased the richness and depth of explorations that could be researched (Key, 2002).
The fact that an exploratory research design was incorporated, a non-probability sampling
strategy was implemented. Additionally a convenient sampling strategy was also
implemented because this type of sampling strategy represents sites or individuals from
which data can easily be collected and where access is convenient (Cresswell, 2007).
The unit of analysis for this research was female shoppers, being the main grocery and
food shoppers in the household, who were living in suburban areas. The participants of
the research, therefore, resided mainly in the Johannesburg and Pretoria suburban areas,
within the Gauteng province and were chosen because these are two of the major
suburban cities in South Africa. The data were collected through means of a multi-method
approach whereby different data collection instruments were applied. In this regard focus
group interviews, sentence completion exercise and a vignette were used which
addressed the objectives set out in the study.
From the findings of the study on the influence of external product attributes on
consumers’ perceived acceptance of new products in general and new products
containing pea protein, it was found that there were not any noticeable differences
between a new food product and a new food product containing pea protein. The
consumer did not indicate a greater willingness to accept general new products in
comparison to a pea protein product. On the contrary, the fact that a new product
contained pea protein did not make any difference. For consumers external product
attributes in general played a major role in their purchasing decision making process. The
most important requirement that the consumers had was that additional information
regarding the pea protein should be provided. It was indicated by the participants that they
would be interested in the pea protein product and consider purchasing it and
incorporating it into their daily diet, providing they knew more about the product and had
sufficient background information about the new product. Furthermore, the importance of
marketing of a new product was highlighted and the fact that the packaging of the new
product should be attractive and eye-catching. Price competiveness was mentioned,
however, should a new and unfamiliar product be introduced by a well-known brand, this
would lower the initial resistance to the new product. One of the main limitations of this study is the relatively small sample size from a
particular area in South Africa and, therefore, resulting in a very selective sample. The
sample, therefore, remains one of convenience which limits the ability to generalize or
transfer findings to a bigger group of consumers. Furthermore the study location was
within a limited area, namely Gauteng. For this reason no assumptions were made nor
were findings considered to be transferable to other population groups or consumer
groups. Another limitation is that the topic of this study is very new and unfamiliar; there
are, therefore, no previous studies with which to compare the findings. This study was
exploratory in nature and the instruments were chosen specifically to explore a new and
unfamiliar topic. The transferability of this study might be limited, but care was taken to
describe the research context in as much detail as possible. In doing so, an attempt was
made to enhance the transferability, should another researcher wish to duplicate the
study.
From the findings of this study certain recommendation can be made as most participants
were of the opinion that they would be interested in the pea protein product and consider
purchasing it and incorporating it into their daily diet provided they knew more about the
product and sufficient background information had been supplied. Furthermore, it was
noted from the findings that these external attributes would influence the new product
acceptability and, therefore, giving the research and developers as well as the marketing
team of a manufacturing company the information necessary to understand the
requirements from the consumers regarding the product containing pea protein better and
how this product should be marketed as a healthy alternative to other vegetable protein
sources. Further recommendations are that should a food manufacturing company wish to
develop a pea protein product, they would need to promote the product beforehand and
create an awareness of the advantages and benefits of pea proteins. This can be done by
editorials in magazines as well as promotions in printed media. Additionally, the
competition between products and brands is fierce and, therefore, manufacturing
companies need to differentiate their products to keep consumers interested in their
product or brand. Pea protein is a new and innovative product and can, therefore, add that
differentiation and benefit to food products.
Future research that can be considered is that of a sensory study, to determine the actual
viability of the pea protein products based on sensory evaluation. One of the main criteria
indicated for the acceptability of a food product containing pea protein has been the taste.
The present research was theoretical and exploratory in nature and, therefore, there were
no actual products which the participants could taste.
Additionally, the inclusion criteria for this study was identified as female shoppers who are
in charge of household grocery and food purchases and were, therefore, specifically
recruited to participate in the research. However, based on a study done by Jensen
(2011), it is recommended that further studies specifically include males because men are
doing more of the household grocery shopping and they are not as brand loyal as females
and would, therefore, be more willing to try and experiment with new food products. A
study based on the gender differences of the acceptability of new products, could highlight
different extrinsic attributes that would influence the purchasing decision. / Business Management / M. Consumer Sc.
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Development of a method to measure protein in red wines : a survey of protein, mannan and tannin in Pinot noir winesSmith, Mark R. (Mark Robert) 24 August 2010 (has links)
A number of methods to isolate and quantify protein in Pinot noir wines were evaluated. The combination of precipitation by acetone containing 10% w/v trichloroacetic acid followed by quantification with the Bradford assay, reported in yeast invertase equivalents yielded the most accurate results when compared to micro-Kjeldahl analysis. The technique was validated by dialysis and proteolysis experiments and was used to assay protein in 57 Pinot noir wines. These wines were found to contain protein concentrations ranging from 49 to 102 mg/L. The mannan and tannin content of the wines was also measured, but no correlation between protein content and concentrations of these components was found. The
presence of protein in red wines greater than 30 years old at concentrations typically found in white wines contradicts the notion that interactions with tannin severely reduce protein levels. / Graduation date: 2011
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Quantitative genetic analysis of agronomic and kernel endosperm traits in quality protein maize (QPM) and investigations of the putative nutritional value of contaminated QPM crops.Machida, Lewis. January 2008 (has links)
The importance of maize in sub-Saharan Africa and the potential of quality protein
maize (QPM) to alleviate the nutritional gap caused by lack of access to adequate
protein rich foods were highlighted. Frustrations from complex inheritance systems of
the QPM trait leading to calls for more information on the inheritance and stability of
the QPM trait, fear of total loss of the QPM trait due to the recessive nature of the
opaque-2 gene to the wild type gene in normal endosperm maize when QPM and
normal endosperm maize coexist, lack of information on the nutritional value of
contaminated QPM grain, and poor linkages with the smallholder farmers were all
cited as drawbacks in the promotion and adoption of QPM. Therefore the objectives
of the study were:
1) To solicit the participation of smallholder farmers in the development and
setting up of QPM breeding goals, objectives and dissemination strategies;
2) To estimate general combining ability (GCA), specific combining ability (SCA)
and reciprocal cross effects on anthesis days, quality traits and grain yield
among the publicly available elite QPM inbred lines;
3) To compare experimental QPM hybrids with selected check cultivars, and
normal endosperm maize hybrids for grain yield performance and kernel
endosperm modification scores;
4) To evaluate QPM hybrids for grain yield and kernel endosperm modification
scores in selected sub-Saharan Africa target environments.
5) To determine the level of normal endosperm maize pollen contamination that
can occur in quality protein maize without loss of nutritional superiority;
6) To estimate the average levels and the patterns of foreign maize pollen
contamination in QPM crops coexisting with normal endosperm maize
varieties.
The contribution of smallholder farmers in setting breeding goals and dissemination
strategies for QPM was solicited. One major finding was that the kernel endosperm
qualities of landrace “Hickory King” need to be incorporated into new QPM varieties
so as to encourage adoption. Farmers preferred getting information on QPM varieties
through their local Agricultural Research and Extension (AREX) officers.
A diallel study of 36 F1 QPM hybrids and their reciprocals was conducted across
seven environments for agronomic traits and three environments for nutritional value
traits. There were significant differences for all traits analysed using Griffing Method 3
model 1. General combing ability effects were significant and important in the control
of anthesis days, kernel endosperm modification, protein content, tryptophan content,
and Quality Index (QI). Specific combining ability effects were highly significant and
important in the control of grain yield. There were significant SCA effects for anthesis
days and QI but the proportions were lesser than the corresponding GCA effects in
both traits. Kernel endosperm modification had significant GCA effects and
nonsignificant SCA effects.
Reciprocal-cross differences were significant for anthesis days, tryptophan content
and QI. Nonmaternal effects were significant for tryptophan content whilst both
maternal and nonmaternal effects were significant for QI and anthesis days.
Nonmaternal effects were relatively more important than maternal effects in all the
cases where there were significant reciprocal-cross differences. The cross with the
highest SCA effects for grain yield was CZL03016/CML144. The most desirable
cross with the lowest anthesis days was CZL03016/CML144 whilst the most
desirable inbred line with the lowest anthesis GCA effects was CZL03016. The
inbred line with the most desirable GCA effects for protein content, tryptophan
content and QI was CML264Q. Inbred line CML264Q crossed to CZL03016 had
significant SCA effects for QI. The most desirable GCA effects for kernel endosperm
modification were associated with inbred line CZL03016 followed by CZL01006.
Maternal effects for both tryptophan content and QI were associated with inbred line
CML264Q.
Genotype by environment interaction effects across all the seven environments were
significant for grain yield and kernel endosperm modification. Check hybrids
performed better than experimental hybrids for grain yield but were not different for
kernel endosperm modification. The normal endosperm maize hybrids were
significantly better for both grain yield and kernel endosperm modification. However,
in all the comparisons the best check or normal endosperm maize hybrid was not
significantly better than the best experimental or QPM hybrid, respectively. The most
desirable score for kernel endosperm modification was from the cross of CZL01006
to CZL03016 though not significantly different from the check hybrid with the best
score. AMMI1 was the best model for kernel endosperm modification scores and
AMMI2 was suitable for grain yield. Both environments and hybrids were diverse.
Grain yield of most hybrids was not stable with specific adaptation to environments.
The most stable hybrid with no specific adaptation was CML176/CML181f with a
mean yield of 6.51t ha-1.
The putative nutritional superiority of normal endosperm maize pollen contaminated
QPM as measured by the QI depended on the environmental conditions. The
moisture stressed environment (CIMMYT Harare) had a lower QI value (0.858) and a
lower tolerance to pollen contamination of 15.3% whereas the grain produced under
near to optimum growing conditions (ART farm) had a higher QI value (0.915) and a
higher tolerance to pollen contamination of 31.9% before total loss of nutritional
superiority. Thus contaminated QPM grain had nutritional superiority up to a certain
point before total loss of nutritional superiority.
Geostatistical analysis was used to determine the levels and patterns of pollen
contamination that occur when QPM and normal endosperm maize crops coexist
under conditions minimising both temporal and geographical isolation to the lowest
possible levels for the two independent crops. Higher pollen contamination levels
were restricted mostly to the sections of the QPM crop proximal to the rows of normal
endosperm maize crop, with the central parts of the QPM crops experiencing
relatively low levels of contamination. For the four experiments (QCS200711,
QCS200712, QCS200721 and QCS200722) in which the thresholds to nutritional
superiority were determined, 87.9%, 94.8%, 62.2% and 65.6% of the crop areas
passed for superior QPM grain, respectively. Estimates for average contamination
levels of homogenous mixtures of grain from each of the nine experiments were
below 20% contamination. The contamination levels were far less than previously
thought.
“Hickory King” kernel quality attributes were important in breeding QPM varieties for
the smallholder farmers. Parents of the 72 hybrids were diverse for the agronomic
characters studied and three of the experimental hybrids were found to be adapted
and comparable to the check varieties. Quality protein maize tolerance to foreign
pollen contamination without loss in nutritional superiority depended on growing
conditions. The coexistence of QPM and normal endosperm maize without total loss
of QPM nutritional superiority was feasible. / Thesis (PhD.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
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Exploring the influence of external product attributes on consumers' perceived acceptance of pea protein as a protein substitute in food productsQuinn, Tineke 07 1900 (has links)
The purpose of this study was to explore the influence of external product attributes on
consumers’ perceived acceptance of pea protein as a protein substitute in food products.
The interest in pea protein as a possible protein source was investigated and the various
advantages of consuming pea protein were highlighted. In previous studies, pea protein
was identified as a possible substitute for red meat (Davies & Lightowler, 1998), but also
as protein containing the amino acid profile which corresponds with the profile
recommended for adults by the Food and Agriculture Organisation (FAO) (Swendseid,
1981). Additionally the nutritional and health benefits, the environmental benefits of
growing pea protein as well as the non-allergen declaration accompanying pea protein
were discussed.
The various factors that will influence the consumer’s decision making process when
introduced to a new and unfamiliar protein source such as pea protein were investigated
in terms of the external product attributes as well as the factors indicated in the Theory of
Reasoned Action (TRA) (Fishbein & Ajzen, 1975). The external product attributes were
identified as the influence of price, marketing of the product, packaging attributes of new
food products, branding importance of a product and new product education and
knowledge perceived necessary for acceptability of a new food product. The additional
factors which were investigated, as indicated by the TRA, included the influence of the
subjective norms or significant others, as well as the consumers’ personal attitude. attitude.
Due to the limited insight and understanding of the influences that external product
attributes have on a consumer’s perceived acceptance of pea protein as a protein
substitute in food products, a qualitative exploratory research design was initiated. An
exploratory research design was incorporated because this afforded the researcher the
opportunity to gather thorough and comprehensive data or information and it also
increased the richness and depth of explorations that could be researched (Key, 2002).
The fact that an exploratory research design was incorporated, a non-probability sampling
strategy was implemented. Additionally a convenient sampling strategy was also
implemented because this type of sampling strategy represents sites or individuals from
which data can easily be collected and where access is convenient (Cresswell, 2007).
The unit of analysis for this research was female shoppers, being the main grocery and
food shoppers in the household, who were living in suburban areas. The participants of
the research, therefore, resided mainly in the Johannesburg and Pretoria suburban areas,
within the Gauteng province and were chosen because these are two of the major
suburban cities in South Africa. The data were collected through means of a multi-method
approach whereby different data collection instruments were applied. In this regard focus
group interviews, sentence completion exercise and a vignette were used which
addressed the objectives set out in the study.
From the findings of the study on the influence of external product attributes on
consumers’ perceived acceptance of new products in general and new products
containing pea protein, it was found that there were not any noticeable differences
between a new food product and a new food product containing pea protein. The
consumer did not indicate a greater willingness to accept general new products in
comparison to a pea protein product. On the contrary, the fact that a new product
contained pea protein did not make any difference. For consumers external product
attributes in general played a major role in their purchasing decision making process. The
most important requirement that the consumers had was that additional information
regarding the pea protein should be provided. It was indicated by the participants that they
would be interested in the pea protein product and consider purchasing it and
incorporating it into their daily diet, providing they knew more about the product and had
sufficient background information about the new product. Furthermore, the importance of
marketing of a new product was highlighted and the fact that the packaging of the new
product should be attractive and eye-catching. Price competiveness was mentioned,
however, should a new and unfamiliar product be introduced by a well-known brand, this
would lower the initial resistance to the new product. One of the main limitations of this study is the relatively small sample size from a
particular area in South Africa and, therefore, resulting in a very selective sample. The
sample, therefore, remains one of convenience which limits the ability to generalize or
transfer findings to a bigger group of consumers. Furthermore the study location was
within a limited area, namely Gauteng. For this reason no assumptions were made nor
were findings considered to be transferable to other population groups or consumer
groups. Another limitation is that the topic of this study is very new and unfamiliar; there
are, therefore, no previous studies with which to compare the findings. This study was
exploratory in nature and the instruments were chosen specifically to explore a new and
unfamiliar topic. The transferability of this study might be limited, but care was taken to
describe the research context in as much detail as possible. In doing so, an attempt was
made to enhance the transferability, should another researcher wish to duplicate the
study.
From the findings of this study certain recommendation can be made as most participants
were of the opinion that they would be interested in the pea protein product and consider
purchasing it and incorporating it into their daily diet provided they knew more about the
product and sufficient background information had been supplied. Furthermore, it was
noted from the findings that these external attributes would influence the new product
acceptability and, therefore, giving the research and developers as well as the marketing
team of a manufacturing company the information necessary to understand the
requirements from the consumers regarding the product containing pea protein better and
how this product should be marketed as a healthy alternative to other vegetable protein
sources. Further recommendations are that should a food manufacturing company wish to
develop a pea protein product, they would need to promote the product beforehand and
create an awareness of the advantages and benefits of pea proteins. This can be done by
editorials in magazines as well as promotions in printed media. Additionally, the
competition between products and brands is fierce and, therefore, manufacturing
companies need to differentiate their products to keep consumers interested in their
product or brand. Pea protein is a new and innovative product and can, therefore, add that
differentiation and benefit to food products.
Future research that can be considered is that of a sensory study, to determine the actual
viability of the pea protein products based on sensory evaluation. One of the main criteria
indicated for the acceptability of a food product containing pea protein has been the taste.
The present research was theoretical and exploratory in nature and, therefore, there were
no actual products which the participants could taste.
Additionally, the inclusion criteria for this study was identified as female shoppers who are
in charge of household grocery and food purchases and were, therefore, specifically
recruited to participate in the research. However, based on a study done by Jensen
(2011), it is recommended that further studies specifically include males because men are
doing more of the household grocery shopping and they are not as brand loyal as females
and would, therefore, be more willing to try and experiment with new food products. A
study based on the gender differences of the acceptability of new products, could highlight
different extrinsic attributes that would influence the purchasing decision. / Business Management / M. Consumer Sc.
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Extração de proteínas e carboidratos da biomassa de Spirulina platensis e caracterização da fração proteica / Protein and carbohydrates extraction from Spirulina platensis biomass and characterization of protein fractionLupatini, Anne Luize 28 March 2016 (has links)
CAPES; CNPQ / A Spirulina platensis é reconhecida como uma fonte não convencional de proteínas, em função da sua constituição favorável deste nutriente (46 a 63%), possuindo concentração superior a das carnes e da soja. Além disso, apresenta potencial como matéria-prima para a produção de bioetanol, podendo acumular entre 8,0 e 14,0% de carboidratos. A fim de abranger o conceito de Biorrefinarias Integradas, o objetivo deste trabalho consistiu em avaliar a extração conjunta de proteínas e carboidratos da biomassa de Spirulina platensis utilizando tratamento ultrassônico e agitação em meio alcalino, e a posterior produção e caracterização do concentrado proteico. Na primeira etapa do trabalho, aplicou-se uma estratégia sequencial de planejamento experimental (Planejamento Fatorial Fracionário (PFF) seguido de Delineamentos Compostos Centrais Rotacionais (DCCR)) para seleção e maximização das variáveis com influência significativa sobre o processo de extração. Com as condições de extração otimizadas, foi possível atingir recuperação final de 75,85% e de 41,54% de proteínas e carboidratos, respectivamente. Na segunda etapa do trabalho foi realizada a precipitação de proteínas, para a separação da fase líquida contendo os carboidratos e obtenção do concentrado proteico, o qual foi caracterizado quimicamente e de acordo com sua funcionalidade tecnológica. O concentrado proteico apresentou coloração verde azulada com 75,97% de proteínas (b.s.), concentrações apreciáveis de aminoácidos, sendo o que o triptofano apresentou o maior escore químico (1,71) e o aminoácido limitante foi a histidina; na análise da estrutura secundária das proteínas, as conformações mais abundantes foram β-folha e α-hélice. Na etapa de avaliação da funcionalidade tecnológica observou-se que o pH apresentou influência nas propriedades de capacidade de absorção de água, capacidade de formação e estabilidade de espuma e emulsão, e capacidade de formação de gel, o que pode ser justificado pela solubilidade desta proteína, que é mínima em pH 3,0 e máxima em 9,0. A concentração de concentrado proteico também interferiu no desempenho destas propriedades; melhores resultados foram obtidos em maiores níveis de concentração, exceto para a capacidade de absorção de água e de óleo. Desta forma foi possível determinar que as proteínas de Spirulina platensis podem contribuir na formulação de alimentos, possuindo características eficazes de formação de emulsões, espumas ou géis, bem como pode ser utilizada como fonte suplementar de proteínas. / Spirulina platensis is considered an unconventional source of protein, because its avorably constitution on this component (46 to 63%), which is higher than the meat and soy. Furthermore, it has potential as a feedstock for bioethanol production and can accumulate between 8.0 to 14.0% of carbohydrate. In order to cover the concept of Integrated Biorefineries, the aim of this study was to evaluate the combined extraction of proteins and carbohydrates from Spirulina platensis biomass using sonication and agitation, under alkaline conditions, and the subsequent production and characterization of protein concentrate. The first stage of this work consisted of applying a sequential strategy of experimental design (Fractional Factorial Design FFD) and Central Composite Rotatable Design (CCRD)) by selecting and maximizing variables with significant influence on the protein and carbohydrates extraction. With the extraction conditions established, a final yield of 75.85% and 41.54% from protein and carbohydrate, respectively, was reached. In the second step, the protein concentrate obtained by precipitation was submitted to chemical and echnological functionality analyzes. The protein concentrate showed blue-green color with 75.97% of proteins (dry weight), appreciable concentrations of amino acids, where tryptophan had the highest chemical score (1.71) and the limiting amino acid was histidine; the secondary structure of proteins showed that the most abundant conformations present were β-sheet and α-helice. At the step of echnological functionality evaluation it was observed that the pH influenced on the properties of water absorption capacity, foaming and emulsion capacity and stability, and gelation capacity; it can be justified by the solubility of this protein which is minimal at pH 3.0 and maximum at 9.0. The level of addition of protein concentrate also interfered on the performance of these properties; better results have been obtained at higher concentrations levels, except for water and oil absorption capacity. Thus, it was confirmed that the Spirulina platensis proteins may contribute in different ormulations of foods, having effective characteristics to form emulsions, foams or gels, and can be used as a supplemental source of protein.
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Extração de proteínas e carboidratos da biomassa de Spirulina platensis e caracterização da fração proteica / Protein and carbohydrates extraction from Spirulina platensis biomass and characterization of protein fractionLupatini, Anne Luize 28 March 2016 (has links)
CAPES; CNPQ / A Spirulina platensis é reconhecida como uma fonte não convencional de proteínas, em função da sua constituição favorável deste nutriente (46 a 63%), possuindo concentração superior a das carnes e da soja. Além disso, apresenta potencial como matéria-prima para a produção de bioetanol, podendo acumular entre 8,0 e 14,0% de carboidratos. A fim de abranger o conceito de Biorrefinarias Integradas, o objetivo deste trabalho consistiu em avaliar a extração conjunta de proteínas e carboidratos da biomassa de Spirulina platensis utilizando tratamento ultrassônico e agitação em meio alcalino, e a posterior produção e caracterização do concentrado proteico. Na primeira etapa do trabalho, aplicou-se uma estratégia sequencial de planejamento experimental (Planejamento Fatorial Fracionário (PFF) seguido de Delineamentos Compostos Centrais Rotacionais (DCCR)) para seleção e maximização das variáveis com influência significativa sobre o processo de extração. Com as condições de extração otimizadas, foi possível atingir recuperação final de 75,85% e de 41,54% de proteínas e carboidratos, respectivamente. Na segunda etapa do trabalho foi realizada a precipitação de proteínas, para a separação da fase líquida contendo os carboidratos e obtenção do concentrado proteico, o qual foi caracterizado quimicamente e de acordo com sua funcionalidade tecnológica. O concentrado proteico apresentou coloração verde azulada com 75,97% de proteínas (b.s.), concentrações apreciáveis de aminoácidos, sendo o que o triptofano apresentou o maior escore químico (1,71) e o aminoácido limitante foi a histidina; na análise da estrutura secundária das proteínas, as conformações mais abundantes foram β-folha e α-hélice. Na etapa de avaliação da funcionalidade tecnológica observou-se que o pH apresentou influência nas propriedades de capacidade de absorção de água, capacidade de formação e estabilidade de espuma e emulsão, e capacidade de formação de gel, o que pode ser justificado pela solubilidade desta proteína, que é mínima em pH 3,0 e máxima em 9,0. A concentração de concentrado proteico também interferiu no desempenho destas propriedades; melhores resultados foram obtidos em maiores níveis de concentração, exceto para a capacidade de absorção de água e de óleo. Desta forma foi possível determinar que as proteínas de Spirulina platensis podem contribuir na formulação de alimentos, possuindo características eficazes de formação de emulsões, espumas ou géis, bem como pode ser utilizada como fonte suplementar de proteínas. / Spirulina platensis is considered an unconventional source of protein, because its avorably constitution on this component (46 to 63%), which is higher than the meat and soy. Furthermore, it has potential as a feedstock for bioethanol production and can accumulate between 8.0 to 14.0% of carbohydrate. In order to cover the concept of Integrated Biorefineries, the aim of this study was to evaluate the combined extraction of proteins and carbohydrates from Spirulina platensis biomass using sonication and agitation, under alkaline conditions, and the subsequent production and characterization of protein concentrate. The first stage of this work consisted of applying a sequential strategy of experimental design (Fractional Factorial Design FFD) and Central Composite Rotatable Design (CCRD)) by selecting and maximizing variables with significant influence on the protein and carbohydrates extraction. With the extraction conditions established, a final yield of 75.85% and 41.54% from protein and carbohydrate, respectively, was reached. In the second step, the protein concentrate obtained by precipitation was submitted to chemical and echnological functionality analyzes. The protein concentrate showed blue-green color with 75.97% of proteins (dry weight), appreciable concentrations of amino acids, where tryptophan had the highest chemical score (1.71) and the limiting amino acid was histidine; the secondary structure of proteins showed that the most abundant conformations present were β-sheet and α-helice. At the step of echnological functionality evaluation it was observed that the pH influenced on the properties of water absorption capacity, foaming and emulsion capacity and stability, and gelation capacity; it can be justified by the solubility of this protein which is minimal at pH 3.0 and maximum at 9.0. The level of addition of protein concentrate also interfered on the performance of these properties; better results have been obtained at higher concentrations levels, except for water and oil absorption capacity. Thus, it was confirmed that the Spirulina platensis proteins may contribute in different ormulations of foods, having effective characteristics to form emulsions, foams or gels, and can be used as a supplemental source of protein.
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