MINISTRY OF EDUCATION AND TRAINING HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING GRADUATION THESIS FOOD TECHNOLOGY INFLUENCES OFF FORMULATIONS, PROCESSING CONDITIONS AND STORAGE ON GABA CONTENT AND QUALITY OF GERMINATED BROWN RICE MILK SUPERVISOR: HOANG VAN CHUYEN STUDENT: NGO GIA BAO SKL 0 0 9 1 5 6 Ho Chi Minh City, August, 2022 HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING GRADUATION PROJECT Thesis code [2022-18116002] INFLUENCES OF FORMULATIONS, PROCESSING CONDITIONS AND STORAGE ON GABA CONTENT AND QUALITY OF GERMINATED BROWN RICE MILK NGÔ GIA BẢO Student ID: 18116002 Major: FOOD TECHNOLOGY Advisor: HOÀNG VĂN CHUYỂN, PhD. Ho Chi Minh City, August 2022 1 HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING GRADUATION PROJECT Thesis code [2022-18116002] INFLUENCES OF FORMULATIONS, PROCESSING CONDITIONS AND STORAGE ON GABA CONTENT AND QUALITY OF GERMINATED BROWN RICE MILK NGÔ GIA BẢO Student ID: 18116002 Major: FOOD TECHNOLOGY Advisor: HOÀNG VĂN CHUYỂN, PhD. Ho Chi Minh City, August 2022 2 THE SOCIALIST REPUBLIC OF VIETNAM Independence – Freedom– Happiness -------- GRADUATION THESIS ASSIGNMENT Student name: Ngo Gia Bao Student ID: 18116002 Student name: __________________________ Student ID: ___________________ Major: Food Technology Class: 18116CLA Supervisor: Dr. Hoang Van Chuyen Email: chuyenhv@hcmute.vn Date of assignment: 14/02/2022 Date of submission: 09/08/2022 1.
Thesis title: Influences of formulations, processing conditions and storage on GABA content and quality of germinated brown rice milk 2. Thesis assignment: Design process of germinated brown rice milk. Determine the effects of soaking time and rice to water ratio to the GABA content of germinated brown rice milk, determine the effects of time and temperature of thermalizing process to the GABA content of germinated brown rice milk, determine the effects of thickeners at different concentrations to the GABA content of germinated brown rice milk, determine the viscosity and stability of germinated brown rice milk by use of different thickeners at different concentrations, determine the preservation parameters for germinated brown rice milk. The content and requirements of the graduation thesis have been approved by the Chair of the Food Technology program Ho Chi Minh City, August 9, 2022 CHAIR OF THE PROGRAM SUPERVISOR (Sign with full name) (Sign with full name) 3 4 ACKNOWLEDGEMENT In order to complete my thesis, a lot of work and time was put in.
There have been many challenges for me during this study. But thanks to my lecturers, my beloveds and others around that have help me and motivate me to move on and coming through. For that, I want to sincerely thank to all the lecturers in charge of the Department of Food Technology, Faculty of Chemical and Food Technology, and Ho Chi Minh City University of Technology and Education for having valuable knowledge and give me the best conditions in equipment as well as facilities for me to complete this thesis. I want to give a sincerely thank mine supervisor, PhD.
Hoang Van Chuyen, who has always been enthusiastically guiding and sharing all teaching knowledge and experience for me to accomplish this graduation thesis. Sincerely, I would like to thank Ms. Ho Thi Thu Trang of the Department of Food Technology for facilitating and helping me able to use the measuring tools and equipment that are available at the laboratory of the Faculty of Chemical and Food Technology. Nevertheless, I would like to send our sincere thanks to our schoolmates, for supporting in the experiment of the thesis and always be there to support me.
I sincerely thank! 1 DECLARATION Except where there is obvious recognition and reference to the work of others, where by declare that all content and material presented and involved in this thesis is my work. We also certify that the contents referenced in the thesis have been adequately and accurately cited in accordance with regulations. 9th August 2022 Signature 2 Table of Contents ACKNOWLEDGEMENT .2 Objective of the thesis .3 Meaning of the thesis. 9 Chapter 2: Literature review.1 Overview about germinated brown rice .2 Overview about germinated brown rice milk .1 Introduction about germinated brown rice milk .2 Introduction about GABA .3 Factors affect the stability of GABA in a product .4 Nutritional value of germinated brown rice milk .5 Health benefits of rice milk.6 Overview of thickening agents used in processing of GBRM.3 Researches about GBRM in Vietnam .4 International Researches about GBRM in foreign.
19 Chapter 3: Materials and methods .2 Determination of water – rice ratio for preparation .3 Storage study of GBRM.1 Method for determination of GABA content using UV-VIS spectrophotometry .2 Determination of viscosity of GBRM with the addition of different thickeners .3 Determination of stability of GBRM .4 Determination of emulsion particle size of GBRM .5 Sensory evaluation of GBRM .7 Determination of bacterial count. 24 Chapter 4: Result and discussion .1 Determination of the suitable soaking time and ratio of rice for achieving GABA.2 Sensory evaluation of the GBRM .3 Effects of heating time and temperature on the GABA content of the germinated rice milk (µg/ml) .4 Influence of different thickener formulations on the stability of the rice milk .5 Determination of the suitable use of thickeners and their effects on the GABA content of GBRM .6 Determination of the preservation parameters of GBRM. 34 Chapter 5: Conclusion and recommendations. 45 4 List of Figures Figure 2.
1:Germinated brown rice and germinated brown rice milk. 2:The structure of Gamma-amino butyric acid. 3:Synthesis pathway of GABA in rice. 4:The chemical structure of xanthan gum.
5:Structure of pectin. 6:Structure of Guar Gum. 1: Diagram of experimental design. 1: GABA content (µg/ml) by soaking time and ratio of rice to water.
2:Sensory evaluation of GBRM. 3:GABA of GBRM at different thermalize temperature and time (µg/ml). 4:Stability (%) of GBRM between the use of hydrocolloids. 5:Seperate time of GBRM between hydrocolloids (h).
6:Viscosity (mPa) of GBRM between different use hydrocolloids and concentrations. 7:GABA (µg/ml) content between hydrocolloids and formulation. 33 5 List of Tables Table 2. 1:Comparison of nutritional values of brown rice and white rice.
1:Ratio of rice – water for soaking of GBR. 2: Ratio of rice to water and time for soaking of GBR. 1:Proximate composition of germinated brown rice milk product. 2: The GABA loss of GBRM preserved at different temperature for 7 days (µg/ml).
3: Microbial count of GBRM preserved at different temperature for 7 days (CFU/ml). 4: pH value of GBRM preserved at different temperature for 7 days. 36 6 ABSTRACT In the recent years, germinated brown rice has been recognized as a nutritious product for consumption for specific people. Rice milk is known to be most convenient and sufficient way to consume germinated brown rice.
Thus researching the formulation, processing conditions and storage conditions effects on the GABA content of this product is necessary. In this study, all the mentioned criteria have been experimented through the GABA content achieved by soaking time and ratio of rice to water, effects of thermalization temperature and duration on the GABA content of the GBRM, effect of different formulation by using different thickeners at different concentrations to the GABA content and stability of the GBRM product, effects of storage parameter on the GABA content. As the result, the soaking ratio of rice to water 1:10 at 8 hours of soaking produce the most favorable GABA content 304.47 µg/ml comparing to other ratio and time for soaking for the purpose of this research. The thermalizing temperature under 90C regardless of time are suitable for retaining the GABA content during processing.
In the use of thickening agents, the mixture of Guar gum and Pectin retain the most GABA content 421.79 µg/ml when added to the rice milk while mixture Guar gum and Xanthan gum create a more stabilized product with the stability approximately 100% after 7 days of storage. Storage condition of the GBRM result in the best quality of storage is when stored at 5C.1 Research rationale Ever since introduced, germinated brown rice is known for its many beneficial to the human health, as the rice contain more nutritional value than regular brown rice, mainly vitamins, antioxidants, sugars, especially the amount of gamma-amino butyric acid (GABA)[1]. This substance is an amino acid which act as a neurotransmitter in the human brain. GABA has been proven to have calming effect, development in the children brain, healing and curing effect in overactive children and autism[2].
Nowadays, more and more product using the germinated brown rice to produce other product which are easier for consumption. Germinated brown rice milk is the most ideal way for consumption, the process for suitable yield of GABA However, the loss of this substance is found to be loss by different influences during process and preserving[3]. Heat is known to be the main cause for the loss of GABA during processing. Research conducted by[4] show that GABA is sensitive to heat, the greater the heat, the greater the loss in GABA.
There are also concerns that the rice – water ratio for extraction and the extraction time can also affect the retrieved GABA content as well as other nutrients post extraction. GABA also known to have chemical interaction with other chemical component within the rice itself, but these interactions mostly occur due to the catalyst components such as enzymes or lipid oxidation[5] Thus for retaining the GABA content, determination of the appropriate conditions for processing, suitable formulation and preservation of the produced germinated brown rice milk is necessary. In this study, effects of parameter including soaking time and ratio of rice, preserving temperature and different formulations of thickening agents (xanthan gum, guar gum, pectin) of the product were investigated.2 Objective of the thesis 1.1 General objective The main objective of this thesis is to investigate the influences of different processing factors for determining the most suitable parameters for manufacturing germinated brown rice milk 1.2 Specific objectives - Achieve the suitable temperature and time for thermalizing the germinated brown rice milk with minimal loss of GABA - Determine the suitable soaking time and ratio parameters for achieving the suitable GABA post soaking - Determine the preserving method and food safety parameters of the GBRM - Determine the suitable formulation of food additives (xanthan gum, guar gum, pectin) and their effects on the GABA content and quality of the germinated brown rice milk - Evaluate the sensory criteria of the germinated brown rice milk 8 1.3 Meaning of the thesis This thesis results an be used as a reference for developing the production procedures of germinated brown rice milk and further studies on the processing of related food products 9 Chapter 2: Literature review 2.1 Overview about germinated brown rice Rice (Oryza sativa L) is the most important cereals product and is the major staple food for most parts of the world[6]. There has been a trend in the current modification of this product by germinating its to achieve more nutritional values, mainly the Gamma-aminobutyric acid content.
Germinated brown rice (GRB) is the unpolished rice that has been germinated for gaining more nutrition. The germinated brown rice has a better texture and flavor, most importantly is that the Gamma-aminobutyric Acid (GABA) is increased[7]. Germinated brown rice is used in many different cuisines such as Japanese and Korean. The nutritional content of the Germinated brown rice appears to be higher than its normal white counterpart.
The nutritional value of brown rice is compared with milled white rice and rice bran is described in the Table 2. 1:Comparison of nutritional values of brown rice, milled and rice bran[8] 10 The production of Germinated brown rice is conducted by soaking the ungerminated brown rice into warm water of (30-40 degree Celsius). At this temperature the enzymes are activated. The rice is swollen with water, enzymes such as phytase, lipase, α-amylase and β-amylase are activated for the purpose of germination[9].