MINISTRY OF EDUCATION AND TRAINING HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING GRADUATION THESIS FOOD TECHNOLOGY DEVELOPING LOW ALCOHOLIC KEFIR BEVERAGE WITH PASSION FRUIT, GAC FRUIT AND GINGER ADVISOR: CAO THI THANH LOAN STUDENT: PHAN NGUYEN THANH TRUC BUI MAI UYEN LINH SKL 0 0 8 9 4 1 Ho Chi Minh City, August, 2022 HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING GRADUATION PROJECT 2022-18116021 DEVELOPING LOW ALCOHOLIC KEFIR BEVERAGE WITH PASSION FRUIT, GAC FRUIT AND GINGER PHAN NGUYEN THANH TRUC Student ID: 17116040 BUI MAI UYEN LINH Student ID: 18116021 Major: FOOD TECHNOLOGY Supervisor: CAO THI THANH LOAN, Ph. Ho Chi Minh city, August 2022 HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING GRADUATION PROJECT 2022-18116021 DEVELOPING LOW ALCOHOLIC KEFIR BEVERAGE WITH PASSION FRUIT, GAC FRUIT AND GINGER PHAN NGUYEN THANH TRUC Student ID: 17116040 BUI MAI UYEN LINH Student ID: 18116021 Major: FOOD TECHNOLOGY Supervisor: CAO THI THANH LOAN, Ph. Ho Chi Minh city, August 2022 THE SOCIALIST REPUBLIC OF VIETNAM Independence – Freedom– Happiness -------- GRADUATION THESIS ASSIGNMENT Student name: Phan Nguyen Thanh Truc Student ID: 17116040 Class: 17116CLA1 Student name: Bui Mai Uyen Linh Student ID: 18116021 Class: 18116CLA2 Major: Food Technology Class: 17116CLA1 – 18116CLA2 Supervisor: Cao Thi Thanh Loan, Ph. Email: thanhloanafu@gmail.com Date of assignment: 20/01/2022 Date of submission: 08/08/2022 1.
Thesis title: Developing low alcoholic kefir beverage with passion fruit, gac fruit and ginger. Thesis assignment: - Evaluate effect of the sugar types, ratio, concentration and kefir grain amount on the production of low alcoholic kefir beverage. - Investigate the fruit juice formula for the final product and evaluate the sensory qualities of the kefir beverages. - Determine the physiochemical and microbiological properties of the passion gac ginger kefir beverage.
- Determine shelflife of the passion gac ginger kefir beverage. The content and requirements of the graduation thesis have been approved by the Chair of the Food Technology program Ho Chi Minh City, August 08, 2020 CHAIR OF THE PROGRAM SUPERVISOR (Sign with full name) (Sign with full name) i DISCLAIMER We declare that the entire content of this thesis is our original work. We declare that all references in the graduation thesis were properly cited in accordance with regulations. ii ACKNOWLEDGEMENTS The successful completion of this thesis has everything to do with the support and guidance given by many people.
Among them, first and foremost we extend our heartfelt gratitude to Ph. Cao Thi Thanh Loan, our supervisor for the enthusiastic support and conscientious guidance. We would like to acknowledge our supervisor for giving us precious suggestions. If not for the motivation provided by our supervisor, this thesis would not have been completed.
We must be thankful to Assoc. Nguyen Tan Dung, Head of the Faculty of Chemical and Food Technology. All the theories we applied to complete this thesis successfully were taught to us by the excellent panel of lecturers in our department. Therefore, we are forever in debt to them for providing us the wisdom to accomplish this task successfully.
We would also like to express our deep thanks to the School Board of Ho Chi Minh University of Technology and Education, the Dean Board, lecturers, and staff from the Faculty of Chemical and Food Technology, who allowed and created favorable conditions for us to do the research at the laboratory. We would like to send the most respectful thanks to Nurturing Foods Co. (Vietnam), and all staff members for providing us with all the necessary resources for the implementation of the thesis. Thanks to everyone for helping us with their suggestions to make the project better, especially Ms.
Hoang Thi Thu and Mr. Tran Trung Tin. Last but not least, we would like to thank our parents and friends for always being with us and supporting us overcome difficulties in the process of implementing the thesis. iii iv v vi vii viii ix x xi xii xiii xiv xv TABLE OF CONTENTS GRADUATION THESIS ASSIGNMENT.
iii TABLE OF CONTENTS .xvi LIST OF FIGURES .xix LIST OF TABLES. xx LIST OF ABBREVIATIONS. Historical development of water kefir. Health benefits of water kefir beverage.
Microorganisms and yeasts in water kefir. The kefir market. Substrates and solvents for F1 water kefir fermentation. MATERIALS AND METHODS.
Production of F1 water kefir beverage. Preparation of passion gac ginger juice. Production of passion gac ginger kefir beverage. Experiment 1: Effect of different sugar types on biomass growth and alcoholic content of water kefir.
Experiment 2: Effect of different ratios of two sugar types on biomass growth and alcoholic content of water kefir. Experiment 3: Effect of sugar concentration and kefir grains rate on biomass growth and alcohol content of water kefir. Experiment 4: Investigation of the appropriate fruit juice mixing ratio for kefir beverages and evaluate sensory of kefir beverages. Experiment 5: Determination the physiochemical and microbiological properties of the passion gac ginger kefir beverage.
Experiment 6: Determination the shelf-life of passion gac ginger kefir beverage. Determination of the alcohol content of kefir water after each fermentation. Determination of the biomass of water kefir grains. Determination of pH .Determination of total soluble solids (TSS).
RESULTS AND DISCUSSION. Effect of different sugar types on biomass growth and alcoholic content of water kefir. Effect of different ratios of two sugar types on biomass growth and alcoholic content of water kefir. Effect of sugar concentration and kefir grain rate on biomass growth and alcoholic content of kefir water.
Investigation of the appropriate fruit juice mixing ratio for kefir beverages and evaluate sensory of kefir beverages. Investigation of gac fruit powder portions. Investigation of ginger portions to minimize the off-odor. Investigation the application of the mixed juice portions on the alcohol production and sensory quality of the kefir drink.
Determination the physiochemical and microbiological properties of the passion gac ginger kefir beverage. Physicochemical criteria of the kefir beverage. Microbiological characteristics of the kefir beverage. Determination the shelflife of passion gac ginger kefir beverage.
Conclusion of main findings. 62 xviii LIST OF FIGURES Figure 2. 1 Some overseas kefir fermented water products. 2 Vinamilk unsweetened kefir yogurt.
3 Vinamilk drinkable yogurt kefir without sugar. 4 Kefir home's kefir soda products. The chemical formula of sodium bicarbonate. 8 Chemical structure of active ingredients of Ginger [96].
9 The main properties of ginger [97]. 1 Activated water kefir grains (Nurturing Foods Co. 2 Types of sugars used in water kefir fermentation. 3 Production of F1 water kefir beverage [8], [27].
4 Production of passion fruit juice. 5 Production of gac fruit solution. 6 Production of ginger juice. 7 Production of passion gac ginger juice.
8 Production of passion gac ginger kefir beverage. 9 Kefir beverages made from passion fruit juice and gac fruit powder 0.5% from left to right. 10 Mixing ratio of fruit juice 10%; 20%; 30% with F1 kefir water. 1 Total aerobic plate count and Lactobacillus spp.
of the F1 kefir water and the passion gac ginger kefir beverage after 24h storing at 3-6oC. 2 Total yeast count of the F1 kefir water and the passion gac ginger kefir beverage after 24h storing at 3-6oC. 3 Total soluble solids (TSS), pH and ethanol content changes of kefir drinks during the storage time (10days). 4 Color parameters changes of the passion gac ginger kefir beverage during storage time (10days).
45 xix LIST OF TABLES Table 1. 1 Overview of genera and species of yeasts and bacteria found in water kefir via culture-dependent and -independent methods. 1 Composition of sugars [61]. 2 Chemical composition of honey [66].
3 The of composition of Lavie natural mineral water ( Lavie product’s label). 4 Composition of passion fruit [76] Nutritional value per 100 g (3. 5 Composition of 100g gac fruit aril [86]. 1 Formula of gac fruit powder ratios in the fruit juice.
2 Formula for examination juice added to enhance the aroma. 3 Formula of ingredients used in juice mixture. 4 Ratios of fruit juice examined for mixing with F1 water kefir solution. 5 Methods for chemical components analysis.
6 Methods for microbiology analysis. 1 Results effect of sugar types on kefir water growth. 2 Composition of sugars [61]. 3 Results effect of sugar ratio on kefir water growth.
4 The initial total soluble solids and pH of sugary medium. 5 Results effect of sugar concentration on kefir water growth. 6 Results effect of kefir grain rate on kefir water growth. 7 Microbiological analysis of the kefir fermented with 5% (12g) kefir grains.
8 Microbiological analysis of the kefir fermented with 10% (24g kefir grains). 9 Sensory evaluation of kefir drinks from passion fruit juice and three different ratios of gac fruit powder ratios (0. 10 Sensory evaluation of kefir drinks from passion fruit juice, gac fruit powder and three different ratios of ginger juice ratios (5%; 10%; 15%). 11 Total soluble solids (TSS), pH and ethanol content of three kefir samples at 0h.
12 Total soluble solids (TSS), pH, ethanol content of kefir samples after storage at 24h. 13 Sensory evaluation of kefir drinks made from the final fruit juice mixture formula with three different ratios (10%; 20%; 30%). 14 Chemical components of the kefir beverage. 42 xxi LIST OF ABBREVIATIONS AAB : Acetic Acid Aateria ANOVA : Analysis of Variance AOAC : Association of Official Agricultural Chemists SD : Standard Deviation CFU : Colony Forming per Unit EPS : Exopolysaccharides LAB : Lactic Acid Bacteria TSS : Total Soluble Solids BWK : Brown can sugar Water Kefir RWK : Refined white sugar Water Kefir GWK : Garape molasses Water Kefir HWK : Honey Water Kefir TCVN : Tiêu chuẩn Việt nam PGG : Passion gac ginger MRS : De Man, Rogosa and Sharpe PDA : Potato Dextrose Agar DNS : 3,5-dinitrosalicylic acid Spp.
: Species xxii ABSTRACT This study aimed to solve the dilemmatic situation of high-alcohol kefir soda in reaching the entire market, particularly children and women. The fermentation of different sugar types, ratios and concentrations, using kefir grains was proposed to produce a low-alcoholic kefir beverage. The microbiological analysis (total aerobic plate count and lactobacillus spp. and yeasts), chemical properties (pH, total solids, ethanol content) were investigated at the end of fermentation and after 24h of the final product.
The results showed that among 4 sugar types of grape molasses, honey, brown cane sugar and refined sugar, the latter two produced the lowest alcohol content, with the optimal concentration of sugar is 5% (12g) with 75% and 25% of brown cane sugar and refine sugar, respectively. Regarding sensory analysis, kefir drink containing 20% juice mixtures of passion fruit, gac fruit, and ginger received high marks for flavor and overall acceptability. Furthermore, with a density of Lactobacillus spp. in the final product of 2.2 x 106cfu/ml, this kefir drink can be considered a promising functional food.
During storage, low decreases of pH, total soluble solids, and color were observed, while the alcohol content slightly increased at day 10. Therefore, the shelf life of passion gac ginger kefir drinks made from natural kefir grains is suggested to be 8 days based on the alcohol content and sensory results. Keywords: low alcoholic kefir beverage, passion fruit, gac fruit, ginger. Problem statement The current COVID-19 virus epidemic has necessitated the usage of non-traditional antiviral agents to lower the risk of infection and enhance patient recovery.
The market demand for nutritious and functional foods has also increased due to the development of economy and the health-concious improvement in awareness of customers. Probiotic drinks were highlighted factors among many choices because of theirs healthy benefits for digestion and immune system.