Manufacturing Process of Almond Milk

Manufacturing process of Almond Milk

Module: Food Manufacturing Engineering Tutor: Dr Jibin He Student: Pedro Pereira Candiani Student number: V8213544 Date of submission: 05/05/2019

Contents 1.

Introduction .......................................................................................................................... 3

2.

Market Justification............................................................................................................... 3

3.

Production process................................................................................................................ 4 3.1.

Formulation ................................................................................................................... 4

3.2.

Storage .......................................................................................................................... 6

3.3.

Type of production ........................................................................................................ 6

3.4.

Processes and equipment ............................................................................................. 7

3.4.1.

Soaking .................................................................................................................. 7

3.4.2.

Blanching and Peeling ........................................................................................... 8

3.4.3.

Grinding ................................................................................................................. 9

3.4.4.

Filtration .............................................................................................................. 11

3.4.5.

Metal detection ................................................................................................... 11

3.4.6.

Pasteurization...................................................................................................... 12

3.4.7.

Packaging............................................................................................................. 13

3.4.8.

Labelling .............................................................................................................. 13

3.5.

Flowchart..................................................................................................................... 14

3.6.

Mass and energy balance ............................................................................................ 15

4.

Food Safety Management system....................................................................................... 16

5.

Key stage definition ............................................................................................................. 17

6.

New design proposition ...................................................................................................... 17 6.1.

High Pressure Process ................................................................................................. 17

6.2.

Ultra high pressure homogenization........................................................................... 19

6.3.

Pulsed electric field ..................................................................................................... 20

7.

References ........................................................................................................................... 22

8.

Appendices .......................................................................................................................... 25 8.1.

Appendix 1: Mass balance........................................................................................... 25

8.2.

Appendix 2: Energy balance ........................................................................................ 26

1. Introduction According to Maghsoudlou, Y. et. al. (2016) and Mintel Academic report (2018), the rise of the vegetable milks is related to the increase of allergies or intolerances to milk protein. In addition, Mintel Academic report (2018) also highlights the environmental impact created by livestock rearing and ethical concerns about the animals as reasons to this growth. Among the numerous options available until this moment, it is possible to find plant-based milk produced from soy, almond, oat, rice, cashew, coconut, flax and a lot of others, as presented by Bridges, M. (2018).

This paper will focus on the almond milk which is an “oil-in-water emulsion with the dispersed phase constituted by complex protein dispersion and oil droplets� as characterised by Hasan, N. A. B. (2012). This beverage, as explained by Valencia-Flores, D. C., et. al. (2013) is a good choice because it has a good nutritional value, with a balanced ratio of protein, fat, fiber, vitamins and minerals, as pointed by Maghsoudlou, Y. et. al. (2016). It has also lower calories when compared to soy and dairy milk and has a low sodium content, as highlighted by Yetunde, A. E. and Ukpong, U. S. (2015)

2. Market Justification The free-from market in the United Kingdom is showing a significant growth in the past few years, 133% over 2013 to 2018, as shown by Mintel (2018). Veganism is one of the reasons that the dairy-free market is growing even more than the gluten-free, as presented by Mintel (2018), which shows a great opportunity for focusing in the vegetable milks, more specifically the almond milk, for the reasons presented in the introduction. This can be observed by the data presented in the Mintel (2018) report, which says that dairy is the most commonly avoided ingredient and 23% of the

consumers look for substitutes. In addition, according to the same report, the projection for the next five years is a strong growth although by a slowing rate.

Moreover, according to Mintel (2017) 31% of the consumers search for products with a shorter list of ingredients. Winston, A. (2015) also presents the same trend and states that this is a movement called “Clean label�, which leads to the choice of the product this report will discuss being an almond milk produced without the addition of sugars, preservatives, artificial colours. The aim is to create a product as natural as possible and reach the existing market for this kind of beverage. A few examples available in the markets is presented in the figure 1 below.

Figure 1: Almond milk brands.

3. Production process 3.1. Formulation The almond milk can be composed by water and almonds only, but some brands adds sugar or sweeteners, vitamins, emulsifiers, acidity regulators, stabilisers and flavours, as seem on several brands’ products like Alpro, Califia, Blue Diamond, Plenish and Rude Health.

The recommended specifications for the almonds are moisture lower than 6.5% and the following, according to UNECE STANDARD DDP-06 provided by the United Nations (2016): •

Intact, it is considered a whole almond if no more than 1/8 th is missing;

•

Well developed, if more than 25% of the almond is shrunken, shrivelled, tough, it must be excluded;

•

The almonds must be without blemishes, area of discoloration, yellowing in more than 25% or the almond must be excluded;

•

Free from pests and damage caused by it;

In addition, according to the same standard, there are 3 classes of almonds, Extra Class, Class I and Class II, which vary by allowing more defects in shape, development, colour and scratches. For almond milk production it is possible to use all three types.

The water used in the production is potable water following the parameters of the Directive 98/83/EC on the quality of water intended for human consumption Storage (1998).

At last, the final ingredient is soy lecithin, an emulsifier that decreases the oil-water interfacial tensions in order to improve the emulsion stability, as explained by Hasan, N. A. B. (2012) and which, as presented by Bueschelberger, H. et. al. (2015), it is one of the most used emulsifiers in the food industry.

Therefore, the initial quantities of the ingredients for the almond milk per day are presented in the table 1 below.

Ingredient

Weight (kg)

Almonds

1656

Lecithin

1.2

Water (soaking+grinding)

8040

Table 1: ingredients.

3.2. Storage Since almonds can only be harvested once a year, it is important to store them in the optimal conditions, so they do not lose quality, according to Shahidi, F., John, J. A. (2013).

According to Kader (2013), the high amount of lipid facilitates the absorption of odours, which makes important to store the almonds in a place free from it and, commonly, almonds are stored in bins, silos or other bulk containers, as explained by Pleasance, E. A., et. al. (2018). The conditions for storage, according to the Almond Board of California (2016), are a cool and dry place, with controlled temperature below 10°C, to prevent insect activity and lipid oxidation, and relative humidity below 65%, so the almond moisture can be maintained below 6%.

Emulsifier chosen, the soy lecithin, must be stored in a dry place with a controlled temperature that do not exceed 23.8°C, as informed by a supplier, Fisher scientific.

3.3. Type of production This report will present the conditions for the production 4000 litres of almond milk per day. This quantity was defined considering a medium business, but with capacity for increasing the production, since the projections this the sector are growth, as presented in the market justification. This number was reached by an estimation of the demand for almond milk. The prediction for the sales of the free-from market for 2018 was

£837mi and 23% of consumers buy dairy substitutes, according Mintel Academic Report (2018). Therefore, it was estimated that the market of dairy substitutes would represent £192.51mi and, according to Higgins, M. (2018), out of three sales of plant-based milk, two are almond milk, which leads to a £128.43mi income per year. After a comparison between different brands like Alpro, Blue Diamond, Innocent, Rude Health, Plenish, an average price per litre was estimated at £1.5, which turns into a demand of 7,135,000 litres of almond milk per month. Since the objective is produce in a small scale at first, the amount proposed, which represents approximately 1.17% of the market, seems feasible.

The production will be carried out in batches, although all the almonds used in the day will be soaked together, stored and then used during the day, since it is necessary to soak the almonds for several hours before grinding for the almond milk preparation.

The production will start at 6:00h in the morning with an interval of one hour between batches and the last batch to starting at 13:00h and finishing at 18:00h.

3.4. Processes and equipment 3.4.1. Soaking As presented by Yetunde, A. E. and Ukpong, U. S. (2015), Kundu, P., Dhankhar, J. and Sharma, A. (2018) and Maghsoudlou, Y. et. al. (2016), the ideal soaking time can vary between 6 and 20 hours. Therefore, in order to allow the production line to work without been required to stop the almonds will be soaked for 12 hours, as previously tested by Kundu, P., Dhankhar, J. and Sharma, A. (2018). Considering that to create a schedule to soak the almonds for each batch separately would be necessary to do this process during the night, all the almonds for the day of production will be soaked in the

end of the previous day and after that, the production will be divided in 8 batches of 206.5kg of almonds. The remaining almonds will be stored under refrigerated conditions, 4°C, until they are required for the production of almond milk. Since no data was found regarding the water absorption of almonds after 12 hours of soaking, an experiment was conducted to determine this. Five samples containing 30g of almonds were soaked in 90 ml of water for 12 hours under cool temperature. After 12 hours the water was drained, the almonds were weighted and an average of 40% of water absorption was found.

According to Aydin, C. (2003), the density of almonds is 995 kg/m3 and the weight of the almonds required per batch, the dimensions of the tank should be enough to support 1.66 m3 of almonds and 4.98 m3 of filtered water, requiring a minimum volume of 6.64 m3.

3.4.2. Blanching and Peeling In addition to the skin removal, which according to Chen, C. et. al. (2005) represents four percent of the total weight of the almond, this step helps to decrease microbiological hazard, for example, bacterial and mould growth, as stated by Grundy, M. M., Lapsley, K. and Ellis, P. R. (2016). Therefore, it is an important stage, considering that the almonds were previously immersed in water for 12 hours, which could lead to an increase of microbiological growth, as stated by Feng, Y., Lieberman, V., Harris, L. J. (2018). To achieve the safety degree required it is necessary to immerse the almonds in hot water, 90°C, for at least 2.5 minutes in order to achieve a 5-log reduction of Salmonella spp, according to the Almond Board of California (2007).

This process consists in a few steps, first, as mentioned above, the almonds are immersed in hot water for 2.5 minutes, then, they go through the rubber rollers, which remove the skins. Finally, the almonds and the skins are dropped into a shaking table and the skins are aspirated away, as presented by the Almond Board of California (2007).

This process will blanch and skin 289.8kg of almonds per hour, and the equipment is presented in the figure 2 below.

Figure 2: blancher and peeler.

3.4.3. Grinding At this stage the blanched almonds and water are grinded into an aqueous emulsion, which will be submitted to a filtering step later to remove the solid portion.

However, this process could lead to metal contamination from the wear caused by metal to metal contact, as stated by Grocery Manufacturers Association (2010). Therefore, it is essential that the equipment is always maintained in good conditions and, also, that an inspection for metal is done afterward grinding.

In addition, to avoid separation of the aqueous emulsion due to the sedimentation and creaming mechanisms as pointed by to Aiello, G., Scalia, G. L. and Cannizzaro, L. (2010), it is required that the grinding process reduces the average particle size to 5 Âľm. However, that is not the only possible measure. As stated by Hasan, N. A. B. (2012), the addition of lecithin can improve the emulsion stability by decreasing the oil and water interfacial tensions, therefore 0.03% (w/w) of lecithin is added for every litres of almond milk prepared, which is enough to improve the stability as tested

by Valencia-Flores, D. C., et. al. (2013).

The equipment chosen for this operation will process the ingredients at the proportion of 281.5kg of almond for 385.45kg of water and 0.15kg of lecithin per hour with a controlled temperature of 45°C, in order to maintain the nutritional content of the ingredients as presented by Aiello, G., Scalia, G. L. and Cannizzaro, L. (2010). An example of the equipment is shown in the figure 3 below.

Figure 3: grinder.

3.4.4. Filtration At this stage the solids are removed from the emulsion. Kundu, P. et. al. (2018) and Hasan, N. A. B. (2012) found similar solids content after sedimentation of almond milk, approximately 25% of solids in the emulsion. Therefore, considering that this stage will remove the solid portion, a 25% of mass reduction will occur after the filtration.

Considering that the grinding process achieved an average particle size of 5 Âľm, the filter needs to be able to hold this size of solids, therefore, a 2500 mesh screen. An example of the equipment is presented below in the figure 4.

Figure 4: filtration equipment.

3.4.5. Metal detection As mentioned above, it is important that metal contamination is investigated. As explained by the Metal Detection Guide provided by the company Mettler Toledo the metal detector works by creating a magnetic field, using a high frequency electric current, in a section of the pipe where the almond milk is pumped. Therefore, if there is any kind of metal (ferrous, non-ferrous and stainless steel) in the almond milk it will disturb the magnetic field and cause a change in the voltage, which will be detected and

the flow will be diverted to dispose the contaminated almond milk. An example is presented in the figure 5 below.

Figure 5: Metal detector.

3.4.6. Pasteurization This process is responsible for the safety of the product, considering the microbiological hazard. As pointed by the US Food and Drug Administration (2018), Bacilus Ereus, Pathogenic E. coli and Salmonella spp. are the bacteria that presents hazards considering the almond milk and should be considered when establishing the time and temperature of this process. Ferragut, V. et. al. (2015) states that heating the product up to 90°C and maintaining for 90 seconds are the conditions required to achieve the desired reduction of the microbiological count. After that the almond milk is cooled down to 4°C, as tested by the same author. This process works by causing a series of events inside the cells leading to its inactivation. According to Cebrián, G. and Mañas, S. P. C. (2017), DNA alterations, loss of membrane functions, ribosome conformation loss, loss of specific protein functions and intracellular components are some events that could occur in consequence of heating.

The initial temperature for the pasteurization is 45°C and considering an equipment with a heating capacity of 60kW and a cooling capacity of 98 kW, according to a supplier (Plevink), it will take approximately one hour to reach 90°C, pasteurize and cool down to 4°C. 3.4.7. Packaging The almond milk will be packed in a carton box with 1l of the product.

3.4.8. Labelling As presented above, the almond milk will be packed in a carton box and, therefore, the label will be printed previously the packaging process occurs. The list of ingredients must contain the almonds in bold, since it is an allergen. The nutritional table of the almond milk is presented below in the table 2:

Almond milk nutritional table (per 100g) Energy

49.1kcal (2.46%RI)

Fat

4.5g (6.43%RI)

Saturated

0.4g (1.78%RI)

Carbohydrates

0.6g (0.21%RI)

Sugars

0.3g (0.37%RI)

Fibre

0.6g

Protein

1.7g (3.36%RI)

Salt

9.2mg (0.15%RI)

Vitamin E

1.912mg (15.93%RI)

Calcium

73.6mg (9.2%RI)

Magnesium

23.9mg (6.38%RI)

Potassium

1mg (0.05%RI) Table 2: Nutritional table

3.5. Flowchart The flowchart of the production of the almond milk is presented below in Figure 6 with the mass changes during the process and the conditions of process.

Figure 6: Flowchart.

3.6. Mass and energy balance The calculations of mass and energy balance are presented in the Appendix 1 and 2 of this report, respectively. The process chosen for the calculation of energy balance is

the pasteurisation, which involves heating up the almond milk to 90°C, maintaining this temperature for 90s and then cooling down to 4°C.

4. Food Safety Management system In order to provide safe food for the consumers, good manufacturing practices (GMP) should be put in place as well as a Hazard Analysis Critical Control Point (HACCP) system. GMP stands for a series of previous actions that an industry must apply before using, it is the minimum standards to ensure the food safety, as presented by Gall, K. (2008). According to the Food Standards Agency (2007) the GMP are necessary so the HACCP can be focused on the significant hazards of the products and processes.

Among the GMP, the Food Standards Agency (2007) highlights a few, as presented below: •

Cleaning and maintenance schedules

•

Chemical and pest control programmes

•

Waste management procedures

•

Personal hygiene training

Once the GMP has been applied, the HACCP is used to identify, evaluate and control the hazards. This tool is divided in principles and the first two involve a hazard analysis of the process and the definition of the critical control points. A critical control point is any stage of the production where, if any problem occurs, could lead to a food safety issue, as explained by the Food Standards Agency.

The almond milk production faces physical, chemical and biological hazards, in several stages of the manufacturing line. Therefore, some of the processes are

responsible for the elimination of those hazards, blanching, metal detection and pasteurization. However, only the metal detection and pasteurization are critical control points, since even if after blanching there are bacteria that have survived it can be killed during the posterior process, the pasteurization. Consequently, it is of extreme importance that these two stages are always with the right parameters.

5. Key stage definition The pasteurisation process is important to ensure the quality and safety of the almond milk and, therefore, is considered a key stage of the product preparation. This is a thermal process and, besides the efficient inactivation of the bacteria that offers a health hazard, there a few disadvantages of this kind of procedure. According to Bevilacqua, A., Campaniello, D. and Sinigaglia, M. (2010), it can lead to loss and degradation of nutritional and sensorial properties. For example, it could lead to degradation of amino acids and vitamins, browning reactions, also known as Mailard reaction, and generation of cooked flavours as explained by Ferragut, V. et. al. (2015).

6. New design proposition 6.1. High Pressure Process According to Bevilacqua, A., Campaniello, D. and Sinigaglia, M. (2010), high pressure processing is characterized as a non-thermal food process, which, as presented by Penchalaraju, M. and Shireesha, B. (2013), is an alternative method to ensure the safety of foods by the use of elevated pressure to inactivate pathogenic microorganisms.

According to Li, X. and Farid, M. (2016), the inactivation of the microorganisms is due to the damage caused to membrane, denaturation of protein and decrease of pH inside

the cell. In addition, according to Dhakal, S. et. al. (2014) this process can maintain the characteristics of the almond milk, like nutritional quality and texture. This process does not depend on the size and shape, as presented by Yordanov, D., G. and Angelova, D., G. (2010), however, it is limited by the moisture, products with low moisture do not achieve enough microbial reduction, as pointed by Bevilacqua, A., Campaniello, D. and Sinigaglia, M. (2010).

Bevilacqua, A., Campaniello, D. and Sinigaglia, M. (2010) explains the procedure as described below and that the equipment is composed by a pressure vessel, a pressure generation system, a temperature control device and a material handling system. The process works by placing the product in the pressure vessel and sealing it. Then, it is filled with water and, then, a pump is used to increase the pressure, which can reach 600MPa according to thyssenkrupp company and Elbrhami, A., A. (2016), up to the required value and it is maintained by the determined time. After completing the time, the vessel pressure is released and the temperature, which can slightly increase during the process, returns to the initial value. An example of the operation is presented by Hiperbaric company and is shown in the figure 7 below.

Figure 7: high pressure process example.

The conditions for processing the almond milk through high pressure process are highlighted by a study done by Avure Technologies (2015) where Salmonella spp., E. coli and L. monocytogenes were successfully inactivated after applying 593 MPa for 3 minutes. Therefore, this is a possible alternative method for the pasteurization.

6.2. Ultra high pressure homogenization Ultra high pressure homogenization is a process for improving the safety and, also, the stability of colloidal fluids, by reducing the size of fat globules, as presented by Briviba, K. et. al. (2016). It consists of pumping the liquid through a homogenizing valve, as explained by Bevilacqua, A., Campaniello, D. and Sinigaglia, M. (2010), using high pressures, up to 350 MPa, as presented by Briviba, K. et. al. (2016). This causes some physical phenomena, for example, cavitation, shear forces and turbulence, as stated by Floury, J. et. al. (2004), and it is the cause of the disruption of microbial cells, as explained

by Kleinig, A., R. and Middelberg, A. P. J. (1998).

This process has been applied to almond milk by several authors to compare the results of ultra high pressure homogenization with other methods. Ferragut, V. et. al.

(2015) states that this procedure results in a stable product, considering both microbiological and physical aspects. A decrease on the fat globule and other dispersed particles size was achieved, without losing vitamins, by Briviba, K. et. al. (2016).

According to Valencia-Flores, D. C., et. al. (2013), treating the almond milk with 200 MPa, at 75°C, presented better results than pasteurization, regarding the microbiological aspect, with counts below the detection level.

6.3. Pulsed electric field This technology uses short pulses of electricity to cause the inactivation of microorganisms, as presented by Li, X. and Farid, M. (2016). According to Amiali, M. and Ngadi, M. O. (2012), this process leads to a minimum loss in flavour and food quality and has a lower environmental impact due to its efficiency.

The equipment is composed by a few components, “a high voltage power source, an energy storage capacitor bank, a switch, a treatment chamber(s), voltage, current and temperature probes, a pump to conduct food through the treatment chamber(s), cooling devices, and a computer or control panel to control operations�, as presented

by Amiali, M. and Ngadi, M. O. (2012). An example of the components is shown in the figure 8 below. As parameters, usually voltages within the range of 20 kV/cm to 80 kV/cm are used for less than 1 second, as explained by Kumar, Y., Patel, K., Kumar, V. (2015).

Figure 8: components.

Regarding the inactivation mechanism, when the pumped product reaches the treatment chamber, pulses of electricity are applied to it, generating a reaction inside the microorganisms’ cells, known as electroporation, as presented by Kumar, Y., Patel, K., Kumar, V. (2015). The electric field causes the cell membrane to disrupt, as explained

by Mohamed, M. A. E. and Eissa, A. H. A. (2012), and can lead to leakage of intracellular compounds according to Roobab, U. et al. (2018), and, therefore, cell death.

Since no data for almond milk processing was found regarding the parameters of this technology (electric field intensity, power and treatment time, as pointed by Li, X. and Farid, M. (2016)), to assure the elimination of the microbiological hazard tests should be done to define the optimal conditions. However, it is important to consider that if a pulse is kept for a long period, this process causes a raise in the temperature, which is an undesirable consequence, as presented by Amiali, M. and Ngadi, M. O. (2012), since this method is an option for the traditional pasteurization.

7. References Aiello, G., Scalia, G. L. and Cannizzaro, L. (2010). Controlled temperature grinding under modified atmosphere for Almond (Prunus Dulcis) paste production. International Journal of Engineering, Science and Technology, 2(9), pp. 69-82.

Almond Board of California. (2007). Guidelines for validation of blanching processes.

Available at: https://www.almonds.com/sites/default/files/blanching-validationguidelines.pdf (Accessed: 02/2019).

Amiali, M. and Ngadi, M. O. (2012). Microbial decontamination of food by pulsed electric fields (PEFs). In: A., Demirci and M., Ngadi, Microbial Decontamination in the Food Industry : Novel Methods and Applications,1st ed., Cambridge, pp. 407-449.

Aydin, C. (2003). Physical properties of almond nut and kernel. Journal of Food Engineering, 60, pp. 315-320.

Bevilacqua, A., Campaniello, D. and Sinigaglia, M. (2010). Use of High Pressure Processing for Food Preservation. In: A., Bevilacqua, M., Corbo and M. Sinigaglia, Application of Alternative Food-Preservation Technologies to Enhance Food Safety & Stability, pp. 114-142.

Bridges, M. (2018). Moo-ove Over, Cow’s Milk: The Rise of Plant-Based Dairy Alternatives. Practical Gastroenterology, pp. 20-27.

Briviba, K. et. al. (2016). Ultra high pressure homogenization of almond milk: Physicochemical and physiological effects. Food Chemistry, 192, pp. 82-89.

Bueschelberger, H. et. al. (2015). Lecithins. In: V., Norm, ed., Emulsifiers in Food Technology, 2nd ed. Oxford: John Wiley and Sons, Ltd., pp. 21-60.

Cebrián, G. and Mañas, S. P. C. (2017). Physiology of the Inactivation of Vegetative Bacteria by Thermal Treatments: Mode of Action, Influence of Environmental Factors and Inactivation Kinetics. Foods, 6(12), pp. 107-128.

Chen, C. et. al. (2005). Flavonoids from Almond Skins Are Bioavailable and Act Synergistically with Vitamins C and E to Enhance Hamster and Human LDL Resistance to Oxidation. American Society for Nutritional Sciences, pp. 1366-1373.

Dhakal, S. et. al. (2014). Effect of high pressure processing on the immunoreactivity of almond milk. Food Research International, 62, pp. 215-222.

Elbrhami, A., A. (2016). A Comparative Study of the Effects of High Hydrostatic Pressure and Ultraviolet Light on Stability, Health Related Constituents and Quality Parameters of Tiger Nut Milk.

University of Guelph.

Available at: https://atrium.lib.uoguelph.ca/xmlui/bitstream/handle/10214/10121/Elbrhami_Asma _201612_Msc.pdf.pdf?sequence=1&isAllowed=y. (Accessed: 03/2019).

European Communities (1998) COUNCIL DIRECTIVE 98/83/EC of 3 November 1998 on the quality of water intended for human consumption. Available at: https://eurlex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:31998L0083&from=EN (Accessed: 03/2019).

Feng, Y., Lieberman, V., Harris, L. J. (2018). An Examination of Microbiological Risks Associated with Almond Soaking and Drying.

Available at: https://iafp.confex.com/iafp/2018/meetingapp.cgi/Paper/17929 (Accessed: 03/2019).

Ferragut, V. et. al. (2015). Quality Characteristics and Shelf-Life of Ultra-High Pressure Homogenized (UHPH) Almond Beverage. Foods, 4, pp. 159-172.

Floury, J. et. al. (2004). Analysis of a new type of high pressure homogeniser. A study of the flow pattern. Chemical Engineering Science, 59, pp. 843-853.

Food Standards Agency (2007). Principles for preventing and Responding to food incidents. Available at: http://www.reading.ac.uk/foodlaw/pdf/uk-07010-incidentsguidance.pdf (Accessed: 03/2019).

Gall, K. (2008). Good Manufacturing Practices and Training. Available at: https://www.foodsafetymagazine.com/magazine-archive1/octobernovember2008/good-manufacturing-practices-and-training/ (Accessed: 03/2019).

Grocery Manufacturers Association (2010). Industry Handbook for Safe Processing of Nuts. Available at: https://www.gmaonline.org/downloads/technical-guidance-andtools/Industry_Handbook_for_Safe_Processing_of_Nuts_1st_Edition_22Feb10.pdf (Accessed: 03/2019).

Grundy, M. M., Lapsley, K. and Ellis, P. R. (2016). A review of the impact of processing on nutrient bioaccessibility and digestion of almonds. International Journal of Food Science and Technology, 51, pp. 1937-1946.

Hasan, N. A. B. (2012). Almond milk production and study of quality characteristics.

Journal of Academia, 2, pp. 1-8.

Higgins, M. (2018). Plant-Based Milk Sales Rise 30% Since 2015 In The UK. Available at: https://www.greenmatters.com/food/2018/08/27/2vp6CH/non-dairy-milk-sales-up (Accessed: 03/2019).

Kleinig, A., R. and Middelberg, A. P. J. (1998). On the mechanism of microbial cell disruption in high-pressure homogenisation. Chemical Engineering Science, 53(5), pp.

891-898.

Kumar, Y., Patel, K., Kumar, V. (2015). Pulsed Electric Field Processing in Food Technology. International Journal of Engineering Studies and Technical Approach, 1(2), pp. 6-17.

Kundu, P. et. al. (2018). Development of Non Dairy Milk Alternative Using Soymilk and Almond Milk. Nutrition and Food Science, 6(1), pp. 203-210.

Li, X. and Farid, M. (2016). A review on recent development in non-conventional food sterilization technologies. Journal of Food Engineering, 182, pp. 33-45.

Maghsoudlou, Y. et. al. (2016). Optimization of Ultrasound-assisted Stabilization and formulation of almond milk. Journal of food processing and preservation, 40, pp. 828839.

Metler Toledo (2016). The Metal Detection Guide. Available at: https://www.gwb.fi/wpcontent/uploads/2017/10/GWB_MT_Metal_Detection_Guide_EN.pdf (Accessed: 04/2019).

Mintel Academic Report (2017) ‘Attitudes towards Healthy Eating – UK’. Available at: http://academic.mintel.com/display/820349/?highlight#hit1 (Accessed: 02/2019).

Mintel Academic report, (2018) ‘Free-from Foods’. http://academic.mintel.com/display/859805/ (Accessed: 02/2019).

Available

at:

Mohamed, M. A. E. and Eissa, A. H. A. (2012). Pulsed Electric Fields for Food Processing Technology. In: A., Eissa, Structure and Function of Food Engineering, Rijeka, Croatia: InTech, pp. 275-306.

Penchalaraju, M. and Shireesha, B. (2013). Preservation of foods by high-pressure processing – a review. Indian Journal of Scientific Research and Technology, 1(3), pp. 3038.

Pleasance, E. A., et. al. (2018). Effects of Storage Conditions on Consumer and Chemical Assessments of Raw ‘Nonpareil’ Almonds Over a Two-Year Period. Journal of food science, 83(3), pp. 822-830.

Roobab, U. et al. (2018). The Impact of Nonthermal Technologies on the Microbiological Quality of Juices: A Review. Comprehensive Reviews in Food Science and Food Safety, 17, pp. 437-457.

Shahidi, F., & John, J. A. (2013). Oxidative rancidity in nuts. In L. J. Harris (Ed.), Improving the safety and quality of nuts (pp. 198–229). Cambridge, UK: Woodhead Publishing Ltd. Thyssenkrupp Industrial Solutions. High-pressure processing. https://www.thyssenkrupp-industrial-solutions.com/high-pressureprocessing/en/downloads (Accessed: 03/2019).

Available

at:

United Nations, (2016). UNECE Standard DDP-6 concerning the marketing and commercial quality control of almond kernels. New York and Geneva, pp. 1-7.

US Food and Drug Administration, (2018). Hazard Analysis and Risk-Based Preventive Controls for Human Food: Draft Guidance for Industry. Available at: https://www.fda.gov/downloads/food/guidanceregulation/fsma/ucm517402.pdf (Accessed: 03/2019).

Valencia-Flores, D., Hernández-Herrero, M., Guamis, B. and Ferragut, V. (2013).

Comparing the Effects of Ultra-High-Pressure Homogenization and Conventional Thermal Treatments on the Microbiological, Physical, and Chemical Quality of Almond Beverages. Journal of Food Science, 78(2), pp. E199-E205.

Winston, A. (2015). Keeping Up with the “Clean Label” Movement. Available at: https://hbr.org/2015/10/keeping-up-with-the-clean-label-movement (Accessed: 03/2019).

Yetunde, A. E. and Ukpong, U. S. (2015). Nutritional and sensory properties of almond (Prunus amygdalu var. dulcis) seed milk. World Journal of Dairy & Food Sciences, 10(2), pp. 117-121.

Yordanov, D., G. and Angelova, D., G. (2010). High Pressure Processing for Foods Preserving. Biotechnology & Biotechnological Equipment, 24(3), pp. 1940-1945.

8. Appendices 8.1. Appendix 1: Mass balance The equations for the mass balance of the production of almond milk is presented below.

Initial quantity of almonds: A = 0.414kg x AM Soaking: M1 = A + W1; W1 = 0.4 x A Blanching and peeling: M2 = 0.9714 x M1 / 8 As explained in the peeling section of this report, the skin of the almonds represents 4% of the total mass. However, as the mass of the almonds was increased by the water absorption this percentage has its value reduced to 2.8571%. In addition, as mentioned above, the batch size is now reduced to 1/8 of the quantity that was soaked.

Grinding: M3 = M2 + W2 + L x AM; W2 = 0.7709 x AM Filtration: M4 = 0.75 x M3 Final: AM = M4 / d Where: AM: litres of almond milk to be prepared A: raw almonds Mi: mass at stage i L: 0.3g of lecithin Wi: water used at stage i d: density of almond milk For the daily production of 4000l of almond milk: Initial quantity of almonds = 1656 kg M1 = 2318.4kg M2 = 281.51kg M3 = 667.11kg M4 = 500.3kg AM = 500l

8.2. Appendix 2: Energy balance The energy transfer will be calculated for the pasteurization stage, considering the initial temperature of 45°C, heat and maintain 90°C for 90 seconds and cool down to 4°C. The volume per batch is 500l, or 499.49kg.

To calculate the density of the almond milk the formula below was used to estimate the density of the lecithin at 45°C, the result was ρ = 792 kg/m3 ρ = 9.2559 × 102 – 4.1757 × 10–1t The density of almonds is 995kg/m3 as already mentioned in the sections above.

Therefore, the density of the almond milk is: ΡAM = 0.917 x 1000kg/m3 + 0.08 x 995kg/m3 + 0.003 x 792 kg/m3 = 998.98kg/m3 Using the formula below to calculate the specific heat of fats, presented by , the specific heat of the lecithin was estimated at the temperature of 45°C. cp = 1.9842 + 1.4733 × 10–3t – 4.8008 × 10–6t 2 Considering the specific heat of the ingredients as shown below: • • •

Water: 4.19 kJ/kg.K Almond: 2.2 kJ/kg.K Lecithin: 1.96 kJ/kg.K

The specific heat o the almond milk was calculated using the formula below: cu = Σci xi Where ci is the specific heat of each ingredient and xi is the percentage in the final product. Therefore, the specific heat of the almond milk is cAM = 4.02 kJ/kg.K. The heat required to increase the temperature to 90°C is: q = 500kg x 4.02kJ/kg.K x 45 K = 90450 kJ The minimum time to reach this temperature, considering a power source of 60kW is: tminutes = (90450.12kJ/60kJs-1)/60 = 25 minutes and 7 seconds.

The heat necessary to decrease the temperature to 4°C is: q = 500kg x 4.02kJ/kg.K x (-86) = 172860 kJ The required time to cool the almond milk to 4°C with a cool capacity of 98kW is: tcool down = (172860kJ/ 98kJs-1)/60 = 29 minutes and 23 seconds.