Beijing University of Agriculture and Harper Adams University College Food Quality with Retail Management Module Title: Food Processing, Preservation and Packaging Assignment Title: A Specification of Food Manufacture Module Tutors: Tan Feng, Lorna White BUA ID: 201021021201 HAUC ID: 11222000 Word Count: 2480 words Date of submitted: 1st March Content Summary2 1. 0 Introduction3 2. 0 The composition and characteristics of yogurt4 2. 1 My opinion on judgments of the yogurt quality4 3. 0 The evaluation of raw material with description and justification of food ingredient4 3. The identification of packaging material and describe the forming process of the container6 4. 0 The flowchart of food processing and packaging7 4. 1 The description of the objectives and manipulations of each section and relatives principles7 5. 0 Three quality issues11 6. 0 The limitation of yogurt and the scheme of product13 Conclusion14 References15 Summary This report is going to make a whole process summarization and analysis of yogurt processing, packaging and preservation. In the first, the report generally describes the development situation of yogurt and introduces the Yili yogurt approximately.
Then, the report starts to make analysis about yogurt in many sections, including the composition and characteristics of yogurt by sensory analysis, the judgments of yogurt quality according to standard, the evaluation of raw material with description and justification of food ingredient (including raw milk, lactic acid bacteria, Food Additives, nutrition and so on), identify the packaging material and the description of the forming process of container, the flowchart of both yogurt processing and packaging (the objectives and manipulations of each section will be described step by step).
After that, there are three quality issues are put forward to be solved, incompletely fermented of yogurt, wrong preservation ways and packaging problems. Finally, there is going to come up with a reformation of Yili yogurt and give some advices. 1. 0 Introduction Over the past decade, the milk industry have rapid advance in China. Per capita consumption of milk had increased from few kilograms to dozens of kilograms. Milk product already become an inevitable nutritious foods, and it is closely bound up with and inseparable with man’s life.
As main manufacturers in China, Yili occupy the dominant position because of its excellent brand and wide product line. Yogurt is the fastest growing milk product for nearly three years relies on the many available varieties, good flavor and elegant packaging. The manufacture of yogurt is a complex process, it is affected by various factors in many sections, such as processing, packaging and preservation. The enterprise may come up against problems in product process, so how to avoid the emergency quality issue is an important point for enterprise. (Yao, Y, C. 2009) 2. The composition and characteristics of yogurt The packaging of Yili yogurt is plastic, people can drink it by riving the cover of yogurt. The appearance of yogurt is white viscous liquid with fragrance. Yogurt is opacity of transparent liquids and absence of particles of visible size. The taste of yogurt is cool, sweet and a little sour. 2. 1 My opinion on judgments of the yogurt quality According to government standard, there are some hygienic indexes to judge the quality of yogurt, such as the content of nitrate and nitrite, the content of benzoic acid, sorbic acid and melamine.
All the indexes of Yili yogurt reach the government standard, and the yogurt need constant refrigeration in the transport process. The storage temperature of yogurt is between 2-6?. The shelf life of yogurt is three weeks, it would cause harm to human body when it is out of date. The packaging of yogurt must be sealed and the yogurt should be thrown away if its packaging is broken. 3. 0 The evaluation of raw material with description and justification of food ingredient The type of production is flavored fermented milk.
The ingredient of yogurt is raw milk, white granulated sugar, lactic acid bacteria (Streptococcus thermophiles, Lactobacillus bulgaricus, Lactobacillus acidophilus and Bifid bacterium) and Food Additives (Gelatin, Pectin). Nutrition content is each containing one hundred grams of 479 kilojoule of energy, 3. 3 grams of protein, 5 grams of fat, 14 grams of carbohydrate, 0. 06 grams of Sodium and 0. 082grams of Calcium. Lactic acid The raw milk hardly contains the lactic acid. After the fermentation, amount of lactose transform into lactic acid.
Lactic acid can restrain harmful bacteria, and promote gastric contents of discharge, in the meanwhile, reduce the gastric acid secretion lead to improve the utilization rate of calcium phosphorus iron. (Yao, Y, C. 2009) Protein Because of the lactobacillus fermented, the protein of yogurt is broken down to imperceptible solidification cheese, peptide and amino acid. So it is easy to be digestive absorption, and improve the protein digestibility. (Yao, Y, C. 2009) Fat The fat of milk in the form of particle shape is scattered in the milk, but in the yogurt, the fat is break down into fatty acid to the benefit of bsorption. The content of free fatty acid and essential amino-acid in yogurt reach 4 times as many as milk. After fermentation, the yogurt contain twice raw milk content of fatty acid. (Yao, Y, C. 2009) Calcium Yogurt is rich in calcium, a cup of yogurt about 150 grams can meet the children’s demand of calcium content per day. (Yao, Y, C. 2009) Lactic acid bacteria Yogurt have abundant lactic acid bacteria, it could be maintain normal intestinal flora balance, regulation of intestinal beneficial bacteria to normal levels by drinking 0. 5-0. 5 Kg per day. In addition, lactic acid bacteria have a beneficial effect, for some instances, it will maintain the ecological balance of intestinal flora, avoid constipation, promote digestion and absorption, against aging and improve human immunity. (Yao, Y, C. 2009) 3. 1 The identification of packaging material and describe the forming process of the container The packaging of Yili yogurt is a kind of multi-layer packaging material which mix the PE, PVDC, adhesive, EVA and Black master batch.
PVDC has good properties to resistance to moisture and oxygen, EVA has good cold-resistance and heat-resistance, black master batch has light-shielding resistance contribute to avoid light irradiation. In general, this kind of yogurt should be preserved between 2-6? , the shelf life is 21 days. So manufacturers choose the double composite film and plastic cup to packaging yogurt. In the transport, the yogurt after packaging to be loaded in corrugated case, it is convenience to transport and storage. In addition, corrugated case will improve the safe of yogurt because of its good cushioning. Li, S, Z. 2006) 4. 0 The flowchart of food processing and packaging Milk storage ; Fresh milk ? v? Add the ingredients v? Preheating/Make uniform quality v? Pretreatment process Sterilization ; Heat preservation v? Pre-cooling v? Add the special ingredients v? Inoculation/Mix the liquid v? Heat preservation for fermentationFermentation section v? Fermentation termination v? Mixing/Refrigeration v?? Packaging and Preservation Package the product ; Preservation 4. 1 The description of the objectives and manipulations of each section and relatives principles 4. . 1 Pretreatment process of milk and mixing section. * The storage of raw milk: monitor the time and measure the temperature of raw milk storage, and active sampling to verification and inspection. Then the raw milk is separated to be fresh milk by separator, all the mechanical impurity is removed in this stage, the raw milk is standardized. (Li, Y. 2008) * Blending process: the ingredients should be adjusted to reach the requirements of product design. It should prevent the fat oxidation while mix raw milk and ingredients.
After mixing it needs to transfer as quickly as possible, the liquid without sterilization and refrigeration should not be place exceed 2 hours. Under the appropriate temperature, add the ingredients into the raw milk, sometimes preliminary dry mixing processing. At this stage, Ingredients index and taste should be concentrated to meet the standard. (Li, Y. 2008) * The milk with ingredients need to preheated under 70? , and then put it into homogenizer after degassing. The objectives of this stage is the good taste of yogurt, it prevents fat rise to the surface and make the fat into particles. (Li, Y. 008) There are some other effects of homogeneity to increase the yogurt quality: First, enhance the tissues texture and cream texture. Second, appropriate to improve the viscosity of final product. Third, reduce the precipitation of whey. In general, homogeneous pressure keeps in the extent from 9. 8MPa to 24. 5MPa. (Li, Y. 2008) * There are three objectives of sterilization: first, it can remove the oxygen of raw milk in order to reduce the REDOX reaction, and promote the growth of lactic acid bacteria. Secondly, because of the denaturation of protein, it improves the hardness and organization of milk.
Thirdly, this is a good method to prevent the whey off. The preheated should be conducted under 90? and continue it for 15 minutes in pasteurized machine. The milk should to keep warm in 40?. It had better remove the oil in the surface so as to degrease the milk during the sterilization process. (Li, Y. 2008) * After sterilization the milk need to be cool down about 40-42? , always this process will conduct in pasteurized machine. (Li, Y. 2008) * Put the mixture of white sugar and other ingredients which need heat insulation into the aseptic milk.
Then put it into sterile glass bottle, leaving no space in it in order to anaerobic conditions of lactic acid fermentation. (Li, Y. 2008) 4. 1. 2 Fermentation section of yogurt. * The inspection before fermentation: In order to make a comparison with theorization index of end product, the product which has not been fermentation should be selected. People need to concentrate on the inoculum size while add bacterium into milk, after 15-20 minutes, they can collect samples. The leavening agent should be inoculated in gnotobasis, mixing the milk and leavening agent to blend well.
This process will finish in the metering pump or fermentation cylinder. (Ye, R, Y. 2000) * The mixture need to keep still for 4-6 hours under 40-42? in the fermentation cylinder. During the period of fermentation, it is not allowed to open mixing until the end of process. * The condition of fermentation time: The texture is concretionary state, and no longer appear whey off of milk. If fermentation time more than 6 hours, the product should be brought to the forefront because of the acid production, it will cause the change of taste. Quick chilling the semi-finished yogurt to 20-24? in the cold type system, and the cooling time no more than 1 hour. The precondition of mixing is the PH value must below 4. 6 and temperature is between 20-24?. It can improve the viscosity of yogurt. After this step, the taste of yogurt will be desired. At last, put the product into refrigerator (2-6? ) for 12 hours in order to increase the viscosity of yogurt. (Hao, D, F. 2009) 4. 1. 3 Packaging and Preservation * The flowchart of packaging: Yogurt after sterilization v
Coiled material ; Print ; Sterilization ; Vertical sealing ; Filling ; Transverse sealing ; Cut off ; Verification ; Counting ; Encasement ; Verification ; Sealing Moreover, it will use the yogurt packaging machine in some procedures. * Yogurt contains no preservatives so that it requires refrigeration. If the temperature is too high, the live lactic acid bacteria will constantly develop lead to high acidity. The worst situation that yogurt goes bad. The shelf life of this kind of yogurt is 2-3 weeks, and the condition of temperature is 2-6?. (Zhang, J. 2012) 5. 0 Three quality issues
Incompletely fermented of yogurt The incompletely fermented means that fermented milk solidify incompletely at a predetermined fermentation time, under the influence, acidity cannot be increased so end failing to ferment. One of the main reasons is phage pollution. Phage can easy to cause pollution in the productive process, reducing the number of bacterium give rise to produce acid slowly. Seriously, bacterium almost all death leads to failure. Poor production workshop environment, unclean air, indiscriminate discharge of raw milk and dirty equipment are the major cause of phage pollution.
After the phage pollution had happened, workshop environment should be given a thorough cleaning, especially the gutter and corner of wall. Increasing the sterilization of fermenting room, change the methods of sterilization and extend the time of sterilization. In addition, the bacterium should be replaced to antiphagin one immediately. The actual results of above measures show that can insure to recover normal production. (Zhang, R, M. 2008) Incorrect preservation methods Temperature The main ingredient of yogurt is biodiasmin.
Normally, the status of biodiasmin is motionless between 0-4? , with the rise of the temperature of the environment, lactic acid bacteria will increase and die rapidly, as a result the product become a nonactin yogurt lead to reduce the nutritive value. So the correct preservation temperature is about 2-6?. Time Long storage time will change the hygienic quality of milk product. So the fresh yogurt should be sold during the right time, and recover the yogurt past the time. The shelf life of yogurt with pasteurization is 21 days. Humidity
For the yogurt, it is best to be preserved in a low humidity environment, damp milk product enhancing microorganism fermentation. Light ray Under the light, the ingredient of yogurt goes bad rapidly, such as fat, vitamins. These ingredients will produce the oxidation-reduction. Avoid light irradiation is important during the process of processing, transportation, preservation and sales. (Lin, H, F. 2006) (Tong, G, P. 2010) Packaging The raw material of corrugated case is paper, it is made by corrugated board with hollow corrugated structure.
After filling, the corrugated case is regard as the best logistics package of yogurt, it is convenience for product storage, transportation and circulation. The usability of corrugated case will be decreased by various kinds of factors in the distribution process. For example, in the transport process, corrugated case may suffer a shock, and case wall tend to grow thin because of the repeated impact between case and product. In addition, the shock in transportation, bumpy road, distant transports way and alternately modes of transportation have a negative impact in case, all these factors cause the serious decline of mechanical property.
Therefore, for the service life and use intensity of case, people need more strict transportation condition, technical test and on-site management, thus, to ensure the safest of yogurt products. (Shen, H. 2006) (Liu, Z. 2009) 6. 0 The limitation of yogurt and the scheme of product In the Chinese market, Yili occupy the dominant position, at the same time, there are many competitors in this market, such as Mengniu, Guangming and Sanyuan. It is a tremendous stress for Yili yogurt, so Yili need to strengthen its position in the market by improving its selling strategy. The first step is to make a pricing strategy.
In order to attract customers, the new products join the discount promotion. One of the benefits is the discount may remind consumer’s desire, another is to create repeat buyers for Yili yogurt. The appropriate promotion is a feasible way to improve the volume as well. Yili invite music star and sports star who have ultra-high popularity in china to endorse the yogurt with the purpose of consumer’s interest. In addition, by the combine of appropriate arrangement and fun activity, Yili can provide the free trial of yogurt contribute to expand popularity by this direct way. Conclusion
A good yogurt product should be perfect in every section, such as the quality of raw material, ingredients, nutrition for people, processing, packaging, preservation, even the selling strategy and so on. Especially, the process of processing, packaging and preservation is important to make sure yogurt’s quality. Every step should be taken great care. In addition, an appropriate marketing strategy is inevitable as well. The discount promotion is the most used method the attract consumers. References 1. Yao, Y, C. 2009. New type of yoghurt starter and high quality probiotic yogurt research.
Jiangsu: Jiangsu Agricultural Sciences. 2. Li, S, Z. 2006. Printing technology of liquid packaging. Beijing: China Packaging Industry. 3. Ye, R, Y. 2000. Agitated yogurt process analysis. Beijing: Science and Technology. 4. Hao, D, F. 2009. Yogurt quality control and the research of prolong the shelf life. Beijing: China Brewing. 5. Zhang, R, M. 2008. Quality problems and solutions of Yogurt product in the common. Xinjiang: Xinjang animal husbandry. 6. Li, Y. 2008. The key control point of processing and the influence factors of the quality of yogurt.
Liaoning: The Beverage Industry. 7. Lin, H, F. 2006. Affect yogurt quality factors and the solutions. Conference paper. 8. Tong, G, P. 2010. The technology of improvement of yogurt quality. Xinjiang: Xinjang animal husbandry. 9. Shen, H. 2006. The problems and solutions of carton in use process. Zhejiang: Packaging World. 10. Liu, Z. 2009. The influence factors of the compressive strength of the corrugated carton. Beijing: China Packaging Industry. 11. Zhang, J. 2012. Extend the shelf life of dairy products. Heilongjiang: China Dairy. The picture of yogurt product