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Determination of oxidative stability and textural properties of quinoa starch encapsulated oil

Rashid, Md Harun Ar LU (2017) KLGM01 20161
Food Technology and Nutrition (M.Sc.)
Abstract
Emulsion is a novel technique to deliver fats and fat soluble compounds in food, pharmaceuticals and cosmetic products. Different emulsifiers are often used to stabilize the emulsions. Chemically modified quinoa starch granule has taken research importance as an emulsifier in last decade. Chemically modified starch stabilized emulsions are now also been dehydrated to facilitate its use multidimensional way. However the current trend is “Natural and Go Green”. Though, previous studies proved long-term storage stability of native quinoa starch stabilize emulsions. But dehydration effect on emulsion droplets as well as the oxidative stability of native quinoa starch stabilized emulsions is still unknown. At the same time, Therefor, the aim of... (More)
Emulsion is a novel technique to deliver fats and fat soluble compounds in food, pharmaceuticals and cosmetic products. Different emulsifiers are often used to stabilize the emulsions. Chemically modified quinoa starch granule has taken research importance as an emulsifier in last decade. Chemically modified starch stabilized emulsions are now also been dehydrated to facilitate its use multidimensional way. However the current trend is “Natural and Go Green”. Though, previous studies proved long-term storage stability of native quinoa starch stabilize emulsions. But dehydration effect on emulsion droplets as well as the oxidative stability of native quinoa starch stabilized emulsions is still unknown. At the same time, Therefor, the aim of this work was to study the protective effects of native quinoa starch against: oxidation, storage deformity of droplets and force compression and compare with chemically (octenyl succinic anhydride) modified quinoa starch. Oil-in-water type Pickering emulsions were stabilized using NS and OSA-modified starch. Emulsions were subjected to heat treatment over the quinoa starch gelatinized peak and conclusion temperature (60 and 75 °C respectively) for 10 minutes. The impact of time, temperature and storage on emulsion droplet properties were assessed. The protective effects of unheated, heated and dried emulsions against oil oxidation were evaluated with differential scanning calorimetry (DSC). This study also investigated the textural properties of dried emulsion by TVT texture analyzer. The higher temperature treatment presented more separated emulsion droplet than lower temperature. Heat treated free native starch formed gelatinized starch network with droplet by entrapping them during storage, where 75 °C heat treated OSA-modified starch stabilized emulsions showed superior storage stability of droplet upon storage. Developed method of oxidative stability analysis by DSC produced reproducible data. Oil emulsifies by native and OSA-modified starch enhanced the oxidative stability significantly. Heat treatment and dehydration of emulsions primarily reduced the oxidative stability in some extent then demonstrated a steadiness against oxidation in storage. In terms of long time storage (5 months), both starch stabilized emulsions, heat treated emulsions and dried emulsions dropped their oxidative stability significantly except 60 °C heat treated OSA-modified starch stabilized dried emulsion. Only this one confirmed subsequent steadiness throughout the storage period. Oil and unheated emulsions showed the same degree of oxidation after five month of storage. Both starch stabilized dried emulsion represented similar physical strength against low compression force. Higher temperature heat treated dried emulsions were stronger than lower temperature heat treated dried emulsion in the mater of larger compression force. Regarding powder sample, weaker strength observed in finer sample and vise versa. (Less)
Popular Abstract
Do you know most of the cosmetics as well as medicine such as lotion, cream, moisturizer, syrup, ointment, etc. are formulated as emulsions? Most of the natural and process food products for instance milk, yoghourt, mayonnaise, drinks etc. are also designed based on emulsion. What is actually an emulsion? Emulsion is a mixture of two immiscible liquids like oil and water. Emulsions are of two types: oil-in water (O/W) and water-in-oil (W/O). Emulsions are quite unstable and can be separated into two phases due to coalescence of droplets, creaming and Ostwald ripening. Thus, this system are often stabilized by different stabilizers for instance, soluble protein, small molecular weight surfactant, polymeric emulsifier and solid colloidal... (More)
Do you know most of the cosmetics as well as medicine such as lotion, cream, moisturizer, syrup, ointment, etc. are formulated as emulsions? Most of the natural and process food products for instance milk, yoghourt, mayonnaise, drinks etc. are also designed based on emulsion. What is actually an emulsion? Emulsion is a mixture of two immiscible liquids like oil and water. Emulsions are of two types: oil-in water (O/W) and water-in-oil (W/O). Emulsions are quite unstable and can be separated into two phases due to coalescence of droplets, creaming and Ostwald ripening. Thus, this system are often stabilized by different stabilizers for instance, soluble protein, small molecular weight surfactant, polymeric emulsifier and solid colloidal particle. Now stabilizer stabilizing emulsion that can also been converted into encapsulated powder are requested since there are huge demands of powder in the industry. At present 50% of industrials raw materials are powder. The demand is increasing day by day as it facilitates the long-term storage, handling and transportation. However most of the stabilizers are either chemically modified or from expensive natural sources. Starch (a hydrocolloid) is most abundant and inexpensive stabilizer, currently used as octenyl succinic anhydride (OSA) modified form. Research showed that native quinoa starch can also stabilize emulsions. But there is a question, is it possible to formulate native starch to stabilize a dehydrated emulsion, and how will that perform in comparison with a chemically modified one? These questions arise because the current trends are environmental sustainability, natural and go green. So far there has been no answer to this.

Therefore, this research study was carried out as a challenge to produce native quinoa starch stabilized emulsion and emulsion powder. Oil-in-water type emulsion was stabilized by native quinoa starch and encapsulated in two different ways. Dehydrated emulsion was obtained by freeze drying of encapsulates. A Differential Scanning Caloritmetry (DSC) technique was developed for rapid analysis of oxidative stability of oil, emulsion and dehydrated emulsion. Oxidative stability of pure oil, chemical modified and native starch stabilized emulsions and dried emulsions were evaluated using the developed method. Another technique was also developed to analyze the physical property of dehydrated emulsion using texture analyzer. Physical properties of chemically modified and natural starch were investigated by this method.

In conclusion, this study showed that the complex oxidation analysis of oil can be simplified and faster by the application of DSC. Both chemically modified and natural quinoa starch can enhance the oxidative stability of oil by emulsification. This stability can be decreases to pure oil level after long term (five month) storage. Heat treatment plus dehydration of emulsion can retain the stability for longer period. Natural starch can protect oil from oxidation as chemical modified starch in dried emulsion condition till five month or longer storage time. In case of physical properties the native starch stabilize dehydrate emulsion was strong against force compression. These results showed that the clean label natural quinoa starch could be a worthy alternative of chemical modified quinoa starch as an emulsifier and can help in environmental sustainability. (Less)
Please use this url to cite or link to this publication:
author
Rashid, Md Harun Ar LU
supervisor
organization
course
KLGM01 20161
year
type
H2 - Master's Degree (Two Years)
subject
keywords
oxidative stability, dried emulsion, Quinoa starch, emulsion, textural properties, food technology, livsmedelsteknologi
language
English
id
8916650
date added to LUP
2017-07-04 10:10:37
date last changed
2017-07-04 10:10:37
@misc{8916650,
  abstract     = {{Emulsion is a novel technique to deliver fats and fat soluble compounds in food, pharmaceuticals and cosmetic products. Different emulsifiers are often used to stabilize the emulsions. Chemically modified quinoa starch granule has taken research importance as an emulsifier in last decade. Chemically modified starch stabilized emulsions are now also been dehydrated to facilitate its use multidimensional way. However the current trend is “Natural and Go Green”. Though, previous studies proved long-term storage stability of native quinoa starch stabilize emulsions. But dehydration effect on emulsion droplets as well as the oxidative stability of native quinoa starch stabilized emulsions is still unknown. At the same time, Therefor, the aim of this work was to study the protective effects of native quinoa starch against: oxidation, storage deformity of droplets and force compression and compare with chemically (octenyl succinic anhydride) modified quinoa starch. Oil-in-water type Pickering emulsions were stabilized using NS and OSA-modified starch. Emulsions were subjected to heat treatment over the quinoa starch gelatinized peak and conclusion temperature (60 and 75 °C respectively) for 10 minutes. The impact of time, temperature and storage on emulsion droplet properties were assessed. The protective effects of unheated, heated and dried emulsions against oil oxidation were evaluated with differential scanning calorimetry (DSC). This study also investigated the textural properties of dried emulsion by TVT texture analyzer. The higher temperature treatment presented more separated emulsion droplet than lower temperature. Heat treated free native starch formed gelatinized starch network with droplet by entrapping them during storage, where 75 °C heat treated OSA-modified starch stabilized emulsions showed superior storage stability of droplet upon storage. Developed method of oxidative stability analysis by DSC produced reproducible data. Oil emulsifies by native and OSA-modified starch enhanced the oxidative stability significantly. Heat treatment and dehydration of emulsions primarily reduced the oxidative stability in some extent then demonstrated a steadiness against oxidation in storage. In terms of long time storage (5 months), both starch stabilized emulsions, heat treated emulsions and dried emulsions dropped their oxidative stability significantly except 60 °C heat treated OSA-modified starch stabilized dried emulsion. Only this one confirmed subsequent steadiness throughout the storage period. Oil and unheated emulsions showed the same degree of oxidation after five month of storage. Both starch stabilized dried emulsion represented similar physical strength against low compression force. Higher temperature heat treated dried emulsions were stronger than lower temperature heat treated dried emulsion in the mater of larger compression force. Regarding powder sample, weaker strength observed in finer sample and vise versa.}},
  author       = {{Rashid, Md Harun Ar}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Determination of oxidative stability and textural properties of quinoa starch encapsulated oil}},
  year         = {{2017}},
}