Research on the ratio of added sugar for the production of tangerine marmalade .... Study on the effect of sugar mix ratio on product quality in tangerine marmalade .... Processing diagr
INTRODUCTION
Research rationale
In the world, the genus Citrus has about 20-25 species, distributed in East, South and Southeast Asia, Australia, the southwest Pacific islands, with many varieties growing throughout the country with a harmonious climate In Vietnam, the genus Citrus has 15 species, mostly grown, including tangerines
Tangerine is the general name only with a number of the same genus Citrus
Vietnam, South China and Japan are considered the birthplace of these tangerine tangerine varieties by people and found wild relatives in this area, as in China Said has been cultivated for at least 3,000 years now and is widely cultivated to get results in many tropical to tropical regions The cultivation of tangerines produces an output of about 33 million, of which 6 countries have an output of 1 million tons or more (Table 1)
Table 1: Tangerines producing countries in the world
No Countries Fruit production in 2017 (million tons)
Vietnam is considered to be in the region of common tangerine (Citrus reticulata) Many varieties of traditional tangerines are widely planted such as tangerine tangerine, with large fruit, thin skin, citrus fruits, sweet water, sweet and fragrant, grown mainly in Bac Giang, Lang Son, Cao Bang, Thai Nguyen, ;
5 Tangerines with sugar, small fruit, thick skin, very sweet, are grown in Phu Tho, Tuyen Quang, Yen Bai, Hanoi, ; Tangerines, small fruits, thick and sour skin, are grown mainly in the mountains with an altitude of 800-1,600m in Lang Son, Ha Giang, Lai Chau, There are many other varieties imported and planted in Tangerines such as pink tangerines, green tangerines, Thai tangerines,
In Vietnam, tangerines are grown mainly for fruit, essential oil distillation and medicine In Traditional Medicine, many parts are used differently such as: Ripe pods (Bare skin), peel of green pods (Serum), outer shell of fruit (Kumquat), Leaves (Quat), seeds (Quat ganglion)
Tangerine peel (Tran derm) is a part widely used in traditional medicine in Vietnam, China, The main ingredient of Tran vera is essential oil with the main ingredients D-limonene, and flavonide, including hesperidin, methylhesperidin, nobiletin, tangeretin, are the active ingredients of most interest in the dermis
In tangerine juice contains a lot of Vitamin C, it contains 36 mg of vitamin C in each fruit Vitamin C is good for your hair, skin, immune system and weight balance, and it's also a great vitamin for your digestive system Vitamin C helps regulate the intestines and improves the absorption of nutrients from other foods In addition, tangerines have only 35 calories in each fruit They contain free fats and antioxidants, which can help slow down the aging process
Tangerine seeds have a bitter taste, calculated in average, in 2 canals and kidneys; has the function of gas, hemolysis, and system; used to treat intestinal prolapse, scrotal pain, inflammation of the mammary glands, back pain with a dose of 3-9g / day
Tangerine leaves have a spicy taste, bitterness, in the two canals and waste, the function of the first, gas, phlegm; used to treat chest pain; cough, breast swelling, intestinal prolapse at a dose of 10-20g/day
Vietnamese tangerines are cheap and have a short harvest time So it's difficult to consume, the value is low Tangerine products are few, not diverse Jam and Marmalade in Vietnam market do not yet have, especially tangerine products
On that basis, I conducted this research in order to diversify products from tangerines, improve the value of tangerine products, help tangerine growers have a stable income, not dependent on the seasons.
Research’s objectives
Research and improve technology in the production of tangerine jams, take advantage of and solve the problem of improving the value of tangerine in the province by taking advantage of cheap and affordable tangerine raw materials, diversifying products tangerine products
1 Survey of demand and sensory assessment of tangerine jam and marmalade from tangerine
2 Research and improve technological process to produce tangerine jam and marmalade from tangerine
3 Quality assessment of jam and marmalade from tangerine based on national standards
- In terms of economy and society:
The successful implementation project will be the basis for the initial production of tangerine jam and tangerine marmalade and transfer the production process to local people to diversify products from tangerines, thereby increasing income and improving life
LITERATURE REVIEW
The scientific basis of the thesis
On the market there are many types of jam with fruits such as strawberrys, oranges, grapes, etc That has been trusted by the people Production and sales of tangerine jam are still quite new, and obscure This can be considered an advantage to help diversify products, increase choices for consumers, especially preserving, and increasing the value of tangerines after harvest, creating jobs for labor
2.1.1 Tangerine peel and tangerine juice overview
Tangerine is a mandarin orange variety called after Tangier, Morocco, where it originated While there are many different types of tangerines available today, they are all called mandarin orange hybrids Because of their intense, sweet flavor, tangerines are a popular citrus fruit They have a reputation for being sweeter than oranges in general As a result, they're a tasty and healthful dessert alternative
Tangerines, like all citrus fruits, are high in vitamin C Tangerines also contain a moderate amount of vitamin A, with 100 grams providing around 14% of your daily necessary vitamin A consumption Eating tangerine peels has also been linked to health advantages Tangerine is a super-flavonoid, or antioxidant, found in the peel
In studies, super-flavonoids have showed promise as a means to decrease cholesterol
Having enough vitamin C in your body has been linked to having good skin
Vitamin C has been demonstrated to play an important function in the production of collagen in the body Collagen is the substance that gives our skin its youthful appearance Vitamin C has also been demonstrated to help prevent and repair skin damage from the sun Another advantage of tangerines' high vitamin C content is that it promotes eye health by preventing cataracts and age-related macular degeneration Vitamin C and other nutritional antioxidants have been shown to help keep your eyes healthy for longer
Tangerine peel is taken by mouth for a variety of reasons, including asthma, indigestion (dyspepsia), cancer prevention, and many others, although there is no clear scientific evidence to back up these claims Tangerine fruit and peel are both edible Tangerine juice can also be prepared from the fruit
2.1.2 Feature of tangerine juice and tangerine peel
It can provide various health benefits to the body in addition to giving a wide range of key vitamins and characteristics Tangerine is a left-handed tree with few qualities and a complete fat You will be challenged on portion sizes in your primary meals because the process of eating will give you a feeling of hunger rapidly and for a long time There is a wide range, much like fruits, with plenty of vitamin C In fact, just one serving can provide up to 26% of your daily vitamin C requirements
Vitamin C is important for a variety of reasons, the most important of which is its impact on immune function
Getting enough vitamin C each day can help lessen the symptoms of common respiratory infections like colds and minimize their duration Not only that, but a lack of this essential vitamin can lead to lowered resistance to illnesses and infections One of the most notable tangerine advantages is its high antioxidant content, which includes naringin, naringenin, nobelitin, narirutin, and hesperidin
Antioxidants are potent molecules that aid in the battle against the detrimental effects of free radicals in the body, lowering the risk of inflammation and chronic diseases such as cancer and diabetes
Cough, nausea, constipation, and flatulence can all be relieved with tangerine peel Repel foul breath and improve sleep quality
2.1.3 The chemical composition and nutritional value of tangerine juice
Table 2 Nutritional composition in 100g of tangerine juice
The fruit, which is high in vitamin C and is used for both fresh consumption and canned juice production, is the most widely used part Tangerine fruits are high in nutrients, have a delightful taste and perfume, and are a good source of anthocyanins/carotenoids, minerals like K, Na, Ca, Mg, and iron, and vitamins, particularly vitamin C (Table 2)
Citrus juice is a good source of flavonoids, which have a variety of biological benefits, including antioxidant properties and the ability to treat cancer Dietary flavonoids, in particular, operate on carcinogenic active chemicals, activate carcinogen detoxification, remove free radicals, govern cell cycle progression, limit cell proliferation, and so forth Preclinical research has shown that these juices have anticancer properties in both in vitro and in vivo settings (lab animals)
Tangerine juice: It has vibrant colors and a pleasant flavor, and it's made from freshly squeezed tangerine juice that's been pasteurized to prevent spoiling
Tangerine syrup is mostly used in the production of soft foods and beverages, but it can also be used to make ice creams, dairy goods, bread products, ready meals, jams, and other syrups
Tangerine Essential Oil is made from the peel of various Citrus Sinensis fruits and is 100% natural This product was created by a mechanical process that used a cold-pressed method with no thermal modifications Then, immediately after extraction, pack it in drums to preserve its qualities
Fruit puree is a product made from fresh fruit or semi-prepared (fruit puree, fruit juice, sulphated fruit ) cooked with sugar to 65-70% dryness, with the addition of pectin or agar-agar to create frozen gel Jam products stand out in the sweet taste and characteristic aroma of the fruit Processing jam is also one of the important measures to preserve fresh fruit The product is completely different from the starting material in terms of usage In the world, fruit puree has been applied in production and trade with ingredients such as strawberries, cherries, blueberries, pineapples, papayas But the products of tangerine puree just stop at manual processing, serving the needs of the family, there has not been any specific research on the production of tangerine puree in the direction of application at the production scale
Marmalade prepared from fruit (fresh, sulfite or frozen) whole or cut, cooked with sugar, with or without added food acids and pectin
Jelly is a type of jam whose main ingredient is fruit juice instead of fresh fruit like jam, then added sugar and pectin, etc to make jam Therefore, jelly is usually clearer and smoother than jam and can use herbs, tea, etc even wine to make jelly instead of fruit
2.2.2 General process of producting tangerine jam and tangerine marmalade
2.2.2.1 General process of producting tangerine jam
Figure 1 General process of producting tangerine jam
2.2.2.2 General process of producting tangerine marmalade
Figure 2 General processing of producting marmalade
2.3 Tangerine production of some northern provinces in Vietnam
Bac Son yellow tangerine is famous for its sunny yellow color, sweetness and aroma, giving the tangerine a special flavor Currently, the total area of tangerine trees in the district is over 600 hectares, of which the area for harvesting is over 400 hectares, the tangerine production of the cooperative in recent years has reached
CONTENT AND METHODS
Content
3.1.1 Survey of demand and sensory assessment of tangerine Jam and Marmalade tangerine products
Conduct surveys on consumption and demand for jam products
3.1.2 Research and improve processing of jam and marmalade products from tangerines
Tangerine pulp is used as raw materials for the production of jam and marmalade from tangerines
Research to build the jam and marmalade production process from tangerine, determine the mixing formula and production conditions Construction is required for citrus raw materials for production
3.1.3 Quality assessment of jam and marmalade from tangerine
3.1.3.1 Food safety assessment based on national standards
Products are assessed for microbiological contamination limits in food according to QCVN 8-3: 2012 / BYT - National technical regulation for microbiological contamination in food The product is determined microorganisms in food according to TCVN 4884-2: 2015 and quantitative Escherichia coli according to TCVN 7924-1: 2008
3.1.3.2 Analyze the composition and indicators of product concern
The product is determined moisture, sugar, dissolved dry matter, vitamim, total ash according to national standards
3.1.3.3 Evaluation of quality variation of jam and marmalade products from tangerine, preserved under normal conditions
1 Determination of microorganisms in tangerine jam products 2 Quantification of Escherichia coli bacteria in tangerine jam products 3 Determination of moisture content of tangerine jam products
4 Determination of total ash in tangerine jam products
15 5 Determination of vitamin C content in tangerine jam products
6 Determination of reducing sugar content in tangerine jam products
7 Evaluation of changes in quality of tangerine jam products preserved under normal conditions
Research methods
3.2.1 Survey of demand and sensory evaluation of tangerine jam and tangerine marmalade
The survey method uses a questionnaire to collect consumer information (age, income, )
+ Analysis assessment table to identify the group of potential customers to consume the product
3.2.2 Approach method and experimental layout
Over the past years, tangerines have been widely used by consumers, many people have expanded cultivation and tending tangerines according to technical processes, bringing into play the value of bringing income to the people However, harvesting tangerines is only seasonal, with a short harvest time (2-3 months), in many places the cost is lower Therefore, to increase economic value for tangerines and tangerine products, group research and apply science and technology to processing and diversifying tangerine products to increase income, increase value and increase income for people
Jam products from tangerine are produced according to the following general process:
Citrus raw materials are processed without seeds, film processing materials and pressed to collect tangerine juice The juice is inhibited and removed from the citrus-bitter ingredients group (Limonin, nomilin, naringin…) Tangerine juice and a part of the untouched tangerine meat are used in different recipes to cook onions and produce tangerine jam Tangerine jam is researched and produced according to the technological process described in Figure 1
Figure 3 Processing diagram of Tangerine Jam
Marmalade products from tangerines are produced according to the following general process:
Citrus raw materials are processed seedless, raw materials processing and pressed to collect tangerine juice The juice is inhibited and removed from the citrus-bitter ingredients group (Limonin, nomilin, naringin…) Tangerine extract and a part of tangerine peel are used in different recipes to cook and produce tangerine Marmalade Tangerine Marmalade is researched and manufactured according to the technological process described in Figure 2
Figure 4 Processing diagram of Tangerine Marmalade
3.2.2.1 Research on the ratio of added sugar for the production of tangerine jam
Table 3 Research on the ratio of added sugar for the production of tangerine jam
Recipes CT1 CT2 CT3 CT4 CT5
Evaluate the sensory quality of each product and choose the right sugar mixing ratio
3.2.2.2 Research on the ratio of added sugar for the production of tangerine marmalade
Table 4 Research on the ratio of added sugar for the production of tangerine marmalade
Recipes CT6 CT7 CT8 CT9 CT10
Evaluate the sensory quality of each product and choose the right sugar mixing ratio
3.2.2.3 Study on the ratio of Cyclo Dextrin to the ability to reduce bitterness of tangerine marmalade
Using research results at home and abroad, we can mix the ratio of raw materials with factors and conditions like the two items below
Next, evaluate the sensory quality of each sample and choose the most appropriate ratio of Cyclo Dextrin to mix
+ Cyclo Dextrin content from the ratio 1000:13 to 1000:21 according to the table below
Table 5 Study on the ratio of Cyclo Dextrin to the ability to reduce bitterness of tangerine marmalade
Recipes CT11 CT12 CT13 CT14 CT15
3.2.2.4 Study on the ratio of Citric Acid added to tangerine jam
Table 6 Study on the ratio of Citric Acid added to tangerine jam
Recipes CT16 CT17 CT18 CT19 CT20
Assess the sensory quality of each product and choose the appropriate citric acid mixing ratio
3.2.2.5 Study on the ratio of Citric Acid added to tangerine marmalade
Table 7 Study on the ratio of Citric Acid added to tangerine marmalade
Recipes CT21 CT22 CT23 CT24 CT25
Assess the sensory quality of each product and choose the appropriate citric acid mixing ratio
3.2.2.6 Study on the ratio of pectin affecting the structure of tangerine jam
Using the research results, we can mix the ratio of ingredients with fixed factors as follows:
+ Ratio of sugar to juice: 60%
Table 8 Study on the ratio of pectin affecting the structure of tangerine jam
Recipes CT26 CT27 CT28 CT29 CT30
Evaluate the sensory quality of each product and choose the most appropriate ratio
3.2.2.7 Study on the ratio of pectin affecting the structure of tangerine marmalade
Using the research results, we can mix the ratio of ingredients with fixed factors as follows:
+ Ratio of sugar to juice: 60%
Table 9 Study on the ratio of pectin affecting the structure of tangerine marmalade
Recipes CT31 CT32 CT33 CT34 CT35
Evaluate the sensory quality of each product and choose the most appropriate ratio
3.2.2.8 Study on the ratio of gelatine to the structure of tangerine jam
Using the research results, we can mix the ratio of ingredients with fixed factors as follows:
+ Ratio of sugar to juice: 50%
Table 10 Study on the ratio of gelatine to the structure of tangerine jam
Reipes CT36 CT37 CT38 CT39 CT40
3.2.3 Food safety assessment of microbiological contamination limits
3.2.3.1 Determination of microorganisms in food according to TCVN 4884- 2:2015
A specified quantity of the test sample, or a specified amount of the initial suspension in the case of other products, is poured onto the surface of a solid agar culture medium in a Petri dish
Other dishes are prepared under the same conditions, using a decimal dilution of the test sample or the initial suspension
Plates were incubated aerobically at 30 °C for 72 h
Calculate the number of microorganisms per gram or milliliter of test sample by the number of colonies obtained in dishes containing less than 300 colonies
Test portion, initial suspension and dilutions
As specified in ISO 6887 or the specific standard relevant to the product concerned
Using a sterile pipette, transfer 0.1 ml of the test sample if the product is liquid or the initial suspension (10-1 dilution in the case of other products) to the center of the two agar plates If plates from more than one dilution are prepared, they can be reduced to one plate [TCVN 6404 (ISO 7218)]
For some products, it is preferable to count small numbers of microorganisms, the limit of detection can be increased by a factor of 10 by inoculating 1.0 ml of the test sample if the product is liquid or 1.0 ml of the sample initial suspension of the product in another form, on the surface of one large agar plate (140 mm) or on the surface of three small agar plates (90 mm) In either case, prepare dual plates using two large agar plates or six small agar plates
Get another jelly plate Using another sterile pipette dispense 0.1 ml of 10-1 diluent (liquid products) or 0.1 ml of 10-2 diluents (other products)
If necessary, repeat the procedure with subsequent decimal dilutions, using a new sterile pipette for each decimal dilution
Carefully spread the inoculum as quickly as possible over the surface of the agar plate, not allowing the array to touch the side of the plate If possible, use the same set of samples for all dilutions from a sample with the highest dilution,
Leave the plates covered for about 15 min at ambient temperature for the inoculum to absorb into the agar
Turn the prepared dishes upside down and place in the incubator (6.3) set at 30 °C in accordance with ISO 7218 Incubate for (72 ± 3) h
NOTE Using a spiral inoculation device for culture, see Annex A
After the specified incubation period, retain plates with less than 300 colonies, if possible Count the colonies on the plates, using a colony-counting device, if necessary Colonies must be counted correctly to avoid miscounting food particles with major colonies
Spreading colonies are considered as single colonies If growth of colonies is expected, examine the plates after 24 h or 48 h and mark visible colonies If colonies grow to less than one-quarter of the plate, count the colonies on the remainder of the plate and calculate the corresponding number for the whole plate If the colony grows to more than one-quarter of the plate, the plate should not be counted If all plates have spreading colonies, count the most appropriate plates and record in the report that the results may be influenced by spreading colonies
3.2.3.2 Quantitative method of Escherichia coli according to TCVN 7924- 1:2008
Inoculate a specified amount of the test sample or a specified amount of the initial suspension onto cellulose membranes coated on modified mineral glutamate agar (MMGA), then incubate at 37 °C for 4 h
Use decimal dilutions of the test sample or of the initial suspension inoculated
23 in two dishes for each dilution, under the same conditions
For isolation, transfer membranes from the recovery phase on MMGA to tryptone-bile-glucuronide (TBX) agar, and then incubate at 44 °C for 18 h to 24 h
The number of colony-forming units (CFUs) of β-glucuronidase-positive Escherichia coli per gram or per milliliter of sample is calculated from the number of typical green CFUs
Test portion, initial suspension and subsequent dilutions
See ISO 6887-1 or the specific standard relevant to the product to be determined
Using the sterile blunt end clamps (6.6), place the cellulose acetate membrane (6.5) on the dry surface of the two MMGA agar plates (5.2.1.3), taking care not to mix air bubbles into the filter membrane Use a sterile spreader (6.12) to flatten the membrane, if necessary
Using a sterile pipette (6.8), place 1 ml of the test sample or initial suspension in the center of the membrane Using a sterile spreader, spread the inoculum evenly over the membrane surface, avoiding spillage from the membrane
Repeat the procedure in 9.2.1 with further decimal dilutions, if necessary, using another sterile pipette and a different sterile spreader for each diluent
Leave the inoculated plates horizontally at room temperature for about 15 min until the inoculum has penetrated deeply into the agar Incubate the plates for 4 h ± 1 h in the incubator (6.2) set at 37 °C with the membrane/agar face up
+ Switch to selective medium and incubate
After recovery, using sterile clamps, transfer membranes from MMGA (recovery medium) to agar plates containing TBX medium
WARNING – The wet film will adhere to the agar surface Avoid air bubbles
Do not use the sampler set
Incubate the plates for 18 h to 24 h in an incubator set at 44 °C and not more than 45 °C, with the membrane/agar side facing up Do not stack discs more than three layers
Counting of colony forming units (CFU)
After the specified incubation period, count typical CFUs of β- glucuronidase-positive Escherichia coli on each agar plate containing less than 150 typical CFU and less than 300 total CFU (typical and atypical)
If the inoculum cannot be separated and typical colonies cannot be observed, dishes containing typical 0 CFU should be considered according to different calculation methods as in clause 10
Calculations should take into account the most common cases when carried out in accordance with good laboratory practice There are also some exceptional but rare cases (e.g very different CFU numbers between two plates from the same diluent, or much different ratios from a single dilution factor between different diluents) plates from two consecutive dilutions) Counting results should be checked and interpreted by a qualified analyst, and the results may also be rejected
For correct results, typical CFUs should be counted on at least one plate containing at least 15 typical blue CFUs
Calculate N, the number of CFUs of β-glucuronidase-positive Escherichia coli present in the test sample per milliliter or per gram of product using the formula (1):
N = (1) Inside Σa is the sum of colonies counted on all plates retained after two consecutive
25 dilutions, with at least one plate containing at least 15 blue CFUs; n1 is the number of plates retained at the first dilution;
V volume of inoculum used per plate, in millilitres; n2 is the number of plates retained at the second dilution; d the dilution factor corresponding to the first dilution is retained [d=1 in the case of (liquid samples) directly inoculated test specimens]
Round the results to two significant figures (see ISO 7218:2007)
3.3.1 Determination of moisture (loss in mass at 103 oC) (based on TCVN 9741: 2013)
Inside: m0 is the initial mass of the test portion, in grams (g); m1 is the mass, in grams, of the test portion after drying
The results are the average of the two determinations, provided that the repeatability requirements are met (see 9.1)
For moisture content in the range 3% (m/m) to 4% (m/m), the difference between the results of two determinations, carried out consecutively (or simultaneously) by the same operator , using the same apparatus, on the same test piece, shall not exceed 0,2% (absolute value)
For moisture content in the range 3% (m/m) to 4% (m/m), the difference between the final results obtained by two laboratories using this method to analyze the same laboratory sample , not more than 0.8% (absolute value)
3.3.2 Method for determination of total ash (based on TCVN 9742: 2013)
- Principle: Decompose organic matter by treating with concentrated hydrochloric acid solution and heating at 550 oC Weigh the rest
Ensure that the crucible is completely clean, then heat for at least 30 min at 550 °C ± 25 °C in the furnace Cool in a desiccator After cooling to room temperature, weigh to the nearest 0.001 g
Open the sample container and immediately weigh approximately 2 g of the prepared test sample, to the nearest 0.001 g, into the prepared crucible Spread the sample evenly over the bottom of the cup
Add the concentrated hydrochloric acid solution dropwise to the test portion in the crucible, using sufficient quantity (approximately 1 ml) to completely moisten the sample
Place the crucible on a cooled electric stove, turn it on to medium and cook for 30 min Raise the hob temperature to the highest setting in three consecutive steps, at each step, cook for 30 min Hold the test portion at the highest heating until no smoke appears for at least 5 min
Place the crucible containing the test portion in the furnace at 550 °C ± 25 °C for 16 h Remove, let cool and add a few drops of water to moisten and disperse the ash Evaporate to dryness on a hotplate as above and return to the furnace and heat for a further 30 min Remove, cool to room temperature in a desiccator, and weigh to the nearest 0.001 g Determine the mass of total ash to the nearest 0.001 g
+ Number of times determined Carry out two determinations on the same test sample
Total ash, expressed as a percentage by mass of dry matter, is calculated using the following formula:
Inside m0 is the mass of the test portion, in grams (g); m1 is the total mass of ash, in grams (g);
RS is the dry matter content of the test sample, expressed as a mass percentage This content is equal to 100 minus the moisture determined, using the method specified in ISO 7513
Take the result as the average of the two determinations, provided that the repeatability requirements are met
For total ash content in the range 10% (m/m) to 22% (m/m), the difference between the results of two determinations, carried out consecutively (or simultaneously) by the same operator operation, using the same apparatus on the same test material, shall not exceed 0.4% (absolute value)
For total ash content in the range 10% (m/m) to 22% (m/m), the difference between the final results obtained by two laboratories using this method for analysis on the same test sample, not more than 1,2% (absolute value)
3.3.3 Method of determining vitamin C content (according to TCVN 4715:1989)
- Principle: Extract vitamin C of the sample with hydrochloric acid, then titrate the reduced ascorbic acid with sodium 2,6 - diclofenolindofenol (Na 2,6 D) solution
Immediately before the test, it is necessary to determine the titer (T) of the 2.6-diclofenolindofenol sodium solution, use a micro pipette to aspirate 1 ml of 0.0001 g/l ascorbic acid solution into a 50 ml conical flask, add 14 ml of distilled water Titrate the above solution with 2.6 diclofenolidofenol sodium solution until the appearance of a pale pink color that does not fade within 30 seconds
The titration of Na 2,6 D, in g/ml, is given by the formula:
V - volume of 2.6 D Na solution used for titration, ml 0.1.10-3- mass of ascorbic acid present in 1ml, g - Proceed:
Weigh 10 g of sample to the nearest 0.001 g If it is a liquid sample, draw 10ml directly into the volumetric flask Transfer the sample to a ceramic mortar, add 5 g of clean quartz sand, pulverize the sample with 15 ml of 2% HCl, quickly transfer the entire sample to a 100 ml volumetric flask, add 2% HCl to the mark, leave for 10 min, shake evenly, filter
Take 5-10 ml of the filtrate into a 50 ml conical flask, add distilled water to 15 ml, and titrate with 2.6 D Na solution until a pale pink color persists for 30 seconds
Standard time should not exceed 2 minutes The volume of the extract was taken so that 1-2 ml of the standard was used up
Simultaneously conduct the standardization of the test sample
Take 5-10ml of 2% HCl (corresponding to the amount of filtrate taken for titration) into a 50ml conical flask Titrate with 2.6 D Na until a pale pink color persists for 30 s
The content of vitamin C (X) in % according to the formula:
T - titration of Na 2,6 D solution against ascorbic acid, g;
V1 - volume of 2.6 D Na solution used for reagent correction titration, ml;
V2 - volume of the first sample dilution volumetric flask, ml;
V3 - volume of extract taken for titration, ml; m - weight of sample to be weighed, g
The result is the average of 2 parallel determinations accurate to 0.0001%
The difference between two parallel determinations is not more than 10 mean results
3.3.4 Method of determining reducing sugar content (according to TCVN 4075:2009)
Weigh, to the nearest 0.1 mg, a mass of sample with a balance, so that in 100 ml of the test sample solution there is about 0.5 g of reducing sugar
Dissolve the test portion with 100 ml of warm water between 600 °C and 700 °C If the sample is not completely dissolved, heat for a further 15 min in a water bath set at 600 °C to 700 °C Transfer the entire test solution to a 250 ml volumetric flask and rinse again with water (the total volume of water in the flask is about 150 ml) Allow the solution to cool to room temperature To remove non-sugar precipitates, add to the flask 10 ml of zinc sulfate solution if the sample mass is not more than 5 g or 15 ml of zinc sulfate solution if the sample mass is greater than 5 g Shake well, then add a volume of 1 M sodium hydroxide solution corresponding to the volume of 1 M sodium hydroxide solution used to neutralize the above volume of zinc sulfate solution, using phenolphthalein indicator in a separate test separate
Shake the solution in the flask well and make up to the mark with water, mix well and allow the solution to stand for 10 min and filter through clean, dry filter paper
Discard the initial filtrate used to rinse the flask, yielding the test sample solution
Add 25 ml of Fehling solution A and 25 ml of Fehling solution B, respectively, into a 250 ml conical flask and mix well Add exactly 25 ml of the sample solution, shake well, and boil for 3 min on the electric stove from the start of boiling Remove to settle the precipitate The solution in the flask shall be of the
33 dark blue color of copper sulfate, if not done with a smaller amount of sample solution
When the copper (I) oxide precipitate has settled, filter the water above the precipitate in the conical flask into the filter funnel, using a vacuum filter Pour boiled water into the conical flask and continue filtering until the water in the conical flask is completely alkaline During filtration always keep a layer of water on the precipitate to prevent copper(I) oxide from coming into contact with air
Place in a conical flask about 20 ml of the iron(III) sulfate solution (3.1) to dissolve the copper(I) oxide precipitate Use a glass rod to gently stir to dissolve the precipitate Replace the upper filter with a new filter suction flask, transfer the solution in the conical flask to the funnel, filter the filter, and rinse the conical flask and funnel several times with boiling water All of them suck the filter down the bottle Remove the filter aspirator and titrate immediately with potassium permanganate solution, until the solution changes color
Determine with the blank in the same way as with the test sample, replacing the test sample solution with distilled water
- Calculate and display the result
The reducing sugar content in terms of glucose, X, expressed as a mass percent, is given by the formula:
Inside: m1 is the mass of sugar converted to Table A.1, in milligrams (mg);
V1 volume of test sample solution, in milliliters (ml);
V2 is the volume of test sample solution taken for determination, in milliliters (ml); m is the mass of the sample, in grams (g);
1000 is the coefficient for converting grams to milligrams;
The difference between the two simultaneous determinations is ± 0.01% Get results accurate to 0.01%
3.3.5 Evaluation of changes in quality of soluble products of tangerines stored under normal conditions
Instant tea samples were selected at different time points and monitored and compared with moisture, sugar, ash, vitamin C, etc
3.3.6 Sensory evaluation method according to TCVN 3215 – 79
When assessing sensory food products by scoring method according to TCVN 3215 - 79, all sensory criteria or individual criteria of the product are used 20 points to build a unified scale of 6 levels of 5 scores (from 0 to 5) where 0 corresponds to the defective product quality level, and from 1 to 5 corresponds to the decreasing defect level At point 5, the product is considered to have no defects in the quality of the comment, the product has good and specific properties for that criterion
Table 11 Product quality level according to sensory quality scores
RESULTS
Survey results on consumer demand for Tangerine jam and Tangerine
Figure 5 Results of a survey on consumer demand for fruit jam products in Thai Nguyen
41 From figure data 5, we have drawn the conclusion that tangerine jam and tangerine marmalade are still a new product in the northern market of Vietnam in general and Thai Nguyen city in particular Fruit jam products that most of the surveyed people have tried but not many products We noticed that Thai Nguyen people tend to go to supermarkets and markets to buy ingredients and food We also found that the majority of women will have easier access to fruit jam products than men, especially female friends who are students or housewives
The age group from 18-24 is considered as a potential customer for tangerine jam products Because they often tend to try new types of products Do not be afraid to experience and explore quality and delicious products Ages 25-35 are also considered loyal customers if they like a product they are more likely to come back and buy that product over a long period of time The rest of the age groups often do not have the habit of buying, younger than 18 years old will often be bought for them by adults, and older, they do not have the habit of using prepackaged products
According to the survey results, most of the surveyed people do not know much about fruit jam products They tend to try all kinds of domestic fruit products
From that, it can be seen that Vietnamese people are still very interested in Vietnamese goods produced and distributed by themselves.
Analysis of research and improve processing of products
4.2.1 Analysis of research and improve processing of Tangerine Jam
4.2.1.1 Study on the effect of sugar mix ratio on product quality in tangerine jam
To know the influence of the percentage of sugar used on product quality (sensory quality), we changed the percentage of sugar used according to the formulas presented in Section 3.2.2.1 under the same working conditions technology Then evaluate the sensory quality of the products obtained according to item 3.3.6, the results are shown in Table 11
Table 11 Effect of sugar ratio on sensory quality of products
Color Smell Taste Status Total
The results of Table 11 show that the percentage of sugar has an influence on the sensory properties of the product, the most influential property is the taste
Specifically, CT5 has the lowest sensory score, the product has a bitter sweet taste and is not harmonious The product CT4 has a too sweet taste, little harmony in taste
CT3 gives the product a harmonious sweet taste CT2 obtained products are slightly pale, no harmony yet The total score of the formula CT3 is also the largest, so choose CT3 for the next study
4.2.1.2 Study on the effect of the ratio of Citric Acid on the ability to adjust taste in tangerine jam
To study the ability of citric acid to improve the taste of tangerine jam, we
43 carried out according to the procedure presented in Section 3.2.2.4 under the same technological conditions Then evaluate the sensory quality of the product obtained according to 3.3.6, the results are shown in Table 12
Table 12 Effect of the ratio of Citric Acid on the ability to adjust taste in tangerine jam
Acid (%) Color Smell Taste Status Total
The results of Table 12 show that the mixing ratio of citric acid affects the sensory properties of the product The most influential property is taste CT16, CT17 for products with unsatisfactory taste CT19, CT20 gives the product a sour, unharmonious taste CT18 for a product with a harmonious taste The total score of CT18 is also the largest, so choose the formula of CT18 for the next study
4.2.1.3 Study on the effect of Pectin ratio on the structure of tangerine jam
To know the effect of pectin ratio on structure of tangerine jam, we changed the ratio of pectin with different concentrations following the procedure presented in section 3.3.6, the results showed in Table 13
Table 13 Effect of pectin ratio on the structure of tangerine jam
Pectin (%) Color Smell Taste Status Total
The results of Table 13 show that the ratio of pectin affects the sensory properties of the product The most influential property is the state Specifically, CT16, CT17 have the lowest status perception score, the product has little state harmony CT19, CT20 does not have a complete harmony of state and taste, this recipe gives a smooth and smooth state but the smell and taste are not harmonious
CT18 has the largest total score, the state of consistency and smoothness, the harmonious taste is not affected by the taste So choose CT18 for the next study
4.2.1.4 Study on the influence of Gelatine ratio on the structure of tangerine jam
In order to know the effect of Gelatine ratio on the structure of tangerine jam, we changed the ratio of Gelatine with different concentrations and followed the procedure described in Section 3.2.2.8 under the same technological conditions Then evaluate the sensory quality of the product obtained according to item 3.3.6, the results are shown in Table 14
Table 14 The effect of Gelatine ratio on the structure of tangerine jam
Color Smell Taste Status Total
The results of Table 14 show that the percentage of gelatine affects the sensory properties of the product, the most influential properties are the properties of the state and the smell Specifically, CT21, CT22 products obtained have a non- uniform, non-comparable state CT24, CT25 products obtained have a
45 homogeneous and mixed state but have a strange smell M3 has the largest total score, has a homogeneous product and does not contain strange odors So choosing CT23 is the best
4.2.2 Analysis of research and improve processing of Tangerine Marmalade
4.2.2.1 Study on the effect of sugar mix ratio on product quality in tangerine marmalade
To know the influence of the percentage of sugar used on product quality (sensory quality), we changed the percentage of sugar used according to the formulas presented in Section 3.2.2.2 under the same working conditions technology Then evaluate the sensory quality of the products obtained according to item 3.3.6, the results are shown in Table 15
Table 15 Effect of sugar ratio on sensory quality of tangerine marmalade
Color Smell Taste Status Total
The results of Table 15 show that the percentage of sugar has an influence on the sensory properties of the product, the most influential property is the taste
Specifically, CT10 has the lowest sensory score, the product has a bitter sweet taste and is not harmonious The product CT9 has a too sweet taste, little harmony in taste
CT8 gives the product a harmonious sweet taste CT7 obtained products are slightly pale, no harmony yet The total score of the formula CT8 is also the largest, so choose CT8 for the next study
4.2.2.2 Research on optimizing the ratio of Cyclo Dextrin to the ability to remove bitterness at normal temperature
To know the influence of the ratio of Cyclo Dextrin on the de-bitterness of tangerine jam and tangerine marmalade, we changed the ratio of Cyclo Dextrin to the tangerine juice, the steps followed the procedure described in Section 3.2.2.3 under the same technological conditions Then evaluate the sensory quality of the product obtained according to item 3.3.6, the results are shown in Table 16
Table 16 Effect of the ratio of Cyclo Dextrin on the anti-bitterness of tangerine marmalade
Màu sắc Mùi Vị Trạng thái
The results of Table 16 show that the ratio of Cyclo Dextrin has an influence on the quality of the product The most influential property is taste Specifically, CT11, CT12 have the lowest sensory evaluation score of the state, the resulting product still has a bitter, unharmonious taste CT14, CT15 for products with chemical taste CT13 gives the product a harmonious taste, no more bitter taste The total score of the CT13 formula is also the largest, so the CT13 formula is selected for the next study
4.2.2.3 Study on the effect of the ratio of Citric Acid on the ability to adjust taste in tangerine marmalade
To study the ability of citric acid to improve the taste of tangerine marmalade, we added citric acid with different concentrations to tangerine marmalade The steps are carried out according to the procedure presented in Section 3.2.2.5 under the same technological conditions Then evaluate the sensory quality of the product obtained according to 3.3.6, the results are shown in Table 17
Table 17 Effect of the ratio of Citric Acid on the ability to adjust taste in tangerine marmalade
Acid (%) Color Smell Taste Status Total
The results of Table 17 show that the mixing ratio of citric acid affects the sensory properties of the product The most influential property is taste CT21, CT22 for products with unsatisfactory taste CT24, CT25 gives the product a sour, unharmonious taste CT23 for a product with a harmonious taste The total score of CT23 is also the largest, so choose the formula of CT23 for the next study
4.2.2.4 Study on the effect of Pectin ratio on the structure of tangerine marmalade
To know the effect of pectin ratio on structure of tangerine marmalade, we changed the ratio of pectin with different concentrations following the procedure presented in section 3.3.6, the results showed in Table 18
Table 18 Effect of pectin ratio on the structure of tangerine marmalade
Pectin (%) Color Smell Taste Status Total
Product quality analysis results
4.3.1 Microoganisms results of tangerine Jam and tangerine Marmalade
The finished product, in addition to checking the content of substances nutrients in the product, microbiological testing is also important Check for microorganisms in the product to make sure it is produced not only good in quality but also ensure food hygiene and safety strictly regulations of the Ministry of Health
Table 19 Microorganisms in the product
Number Experimental criteria Test method Unit
According to Vietnamese standards on jam products (TCVN 6846:2007) the quantity Permissible aerobic microorganisms in canned jam products must be smaller 3 Based on the results of the table above, we can see that the tangerine marmalade and tangerine marmalade products after the cooling period met the VSV safety standards in terms of total quantity
The product goes through a phase Cooking and pasteurization should have the effect of killing microorganisms present in the product, contributing to prolong storage time With the above jam product, it can be used well in about 6 months
4.3.2 Evaluate the nutritional quality of the tangerine jam and the tangerine marmalade
Table 20 Product quality analysis results
Number Experimental criteria Test method Unit
Average total acid content in mixed jam products tangerine is 4.96mg/100g
This amount of acid is suitable for food products fruit jam box Normally, canned fruit products have an acid content of 0.5 - 1%, for example mango jam or marmalade puree is 0.6 - 1% Jaw The right amount of acid in the product has the effect of preserving, inhibiting the activity of microorganisms in order to prolong the storage time, reduce the pasteurization time for the product, reduce production costs In addition, this amount of acid also creates a harmony of flavor for product
One of the important criteria of canned fruit and vegetable products in general and canned jam in particular is the norm of Vitamin C Vitamin C content has in a product indirectly indicates the quality of that product Vitamin content C in the material is relatively 49.6%, however, through the cooking process, the in bacteria, the Vitamin C content is greatly reduced due to the influence of temperature
According to the research results, the Vitamin C content of mandarin marmalade and mandarin marmalade products is 4.96% and 3.95%, slightly lower than other products (Example: mango and papaya jam products is 22.18%, pineapple jam is 16.10%), contribute to supplementing the amount of Vitamin C for users
Along with that, sugar is an important factor that helps prolong the shelf life and contribute to increase the sensory as well as nutritional value Total sugar content the average amount in the product after analysis was 33.24% and 36.99%
This sugar content is quite low for canned fruit products
Go through the table and compare with the criteria of other canned fruit and jam products previously studied, we concluded that this is a product that supplements nutrients for users and has long-term preservation value
DISCUSSION AND CONCLUSION
Discussion
Because the process of doing the thesis took place only in a short time, I have not yet time to dig deeper Therefore, in order to have a better quality tangerine jam and marmalade, meeting increasingly demanding requirements of the market, it is necessary to continue to study the following issues:
- Survey more about consumption trends of potential customers
- According to studies on jam as well as shelf life of other jam products on the market, the shelf life of puree can be 9-12 months under normal conditions, but tangerine puree products and my processed tangerine marmalade has a shelf life of 4-6 months, worse than other products the same type is 5-6 months The poorer preservation time is due to the lack of hygiene during the processing, the lack of processing tools, the poor sterilization and the limitation of preservative additives
Therefore, it is necessary to further research and supplement the necessary processing tools to ensure hygiene and technology requirements
- Determination of the remaining microbiological criteria of the product immediately after production: For example Coliforms and molds,
- Determine the remaining criteria on chemical composition, nutritional composition contained in the product
- Add other ingredients to increase the quality of the product
- Researching and surveying raw materials, selecting materials for production application on a large scale
- Research user reactions to make reasonable adjustments
- Select packaging design and label design for the product when it is mass- produced
Conclusion
5.2.1 Survey on consumer tastes and preferences for tangerine jam and tangerine marmalade products
Because of the covid19 pandemic, our research team only conducted a survey of local consumer needs and tastes, after the survey and analysis, we found that tangerine jam and tangerine marmalade is a product brand new, 95% of the people surveyed have not heard of tangerine jam before The tendency of young people to have easier access to new products, from which we realize that this is a potential customer for fruit jam products in the future The majority of people surveyed are particularly interested in domestic products Prioritizing Vietnamese products, but we have not taken full advantage of the advantages that we have
5.2.2 Improving procuction process for tangerine jam and tangerine marmalade
5.2.2.1 Developing production process for tangerine jam products
Building a production process for tangerine jam products: The tangerine raw materials, after being selected, are cleaned, filmed and seeded, then pressed to get the juice The auxiliary ingredients were mixed (sugar ratio 1:1,25, Citric Acid 0.5% and Cyclo Dextrin 1%) compared to the volume of the mixture of tangerine juice, and then when starting to heat, mix the juice with Pectin 0.6% and cooked at ≤ 1000C After the concentration is complete, bring the mixture to mix and add 0.05%
Gelatine After cooking, jam is poured into sterilized glass jars, closed with lids, stored at 0℃-5℃ Finally, check product quality according to standards (TCVN 10393:2014) The product has a good sensory rating
5.2.2.2 Developing a production process for tangerine marmalade products
Building a production process for tangerine marmalade: Tangerine raw materials, after being selected, cleaned, peeled and pressed for juice After that, it was mixed with Cyclo Dextrin (ratio of 1%) compared to the mass of the tangerine juice mixture, let it rest for 30 minutes, continued to mix with sugar (ratio 1:1,25) and citric acid (ratio 0 0) .05%) At the beginning of heating, mix the juice with Pectin 0.6% and cook at ≤ 1000C After concentrating the mixture After cooking, jam is poured into sterilized glass jars, closed with lids, stored at 0℃-5℃ Finally,
5.2.3 Quality assessment of jam and marmalade from tangerine
Based on the results, we can see that the tangerine marmalade and tangerine jam products after the cooling period met the VSV safety standards in terms of total quantity
The product goes through a phase Cooking and pasteurization should have the effect of killing microorganisms present in the product, contributing to prolong storage time With the above jam product, it can be used well in about 6 months
This is a product that supplements nutrients for users and has long-term preservation value
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