Pick one product category (Fruit/vegetables, meat, dairy) and discuss the packaging systems used for each of these products and one product category form the product group with the emphasis on active, intelligent packaging systems that will help preserve the quality and safety of those products. (3000 words) The written assignment should be formatted like a scientific paper with a title, abstract, introduction, body containing information with appropriate sub heading, conclusion and references. 1.0 Introduction The significance of packaging in food can be traced back to ancient times where simple materials like leaves, bark and animal skin were used to store and carry food when early societies started to travel and trade (Karaman, Özer, Pascall, & Alvarez, 2015). Food packaging plays an integral part of food processing with primary function of protection and shelf life extension of food through prevention of outside contaminants and loss of components like aroma, moisture from the food products along the distribution chain (Ahvenainen, 2003). On the other hand Karaman et al. (2015) states role of packaging as a useful marketing tool through product consumer interface by conveying product information to the consumers on the product ingredient, nutritional value and aesthetical appeal of the product. Marsh and Bugusu (2007) describes role of packaging in reducing food wastage caused due to spoilage, ease in product traceability, convenience and product integrity. Milk and dairy products are considered food of high nutritional value and also serves as a nutritional media for the growth of microorganisms causing fast deterioration of milk. The shelf life of milk and dairy products is dependent on several factors starting from the microbial load in raw milk, the processing conditions and sanitization of processing equipment (I. Arvanitoyannis & Tziatzioa, 2012). Among the different types of milk products, cheese has the most varieties of more than 2000 different varieties. Cheese is a product obtained from coagulation of milk with bacterial culture, rennet and acid, followed by whey separation, pressing, cheddaring, salting and molding. The production procedure varies for each cheese product type. Cheese is a complex matrix containing network of various cheese components like fat, protein, moisture and the added cheese microflora, which makes the shelf life of cheeses very unpredictable and unstable (Cerqueira et al., 2010). Based on the moisture content cheese can be further classified into hard cheese containing moisture content of as low as 20 to 42%, 44 to 55% for semi hard and more than 55% soft cheese, (Matteo Alessandro Del Nobile & Conte, 2013). The shelf life of cheese is dependent on the moisture content, cheese composition, the temperature treatment during distribution and storage; where high moisture content cheese are more prone to deterioration by spoilage bacterial and fungal microorganisms and also more susceptible to proteolysis and lipolysis due to high fat and protein content. Packaging material selected for preservation of quality and freshness of cheese is specific to each cheese types and is dependent on initial milk quality, starter cultures, and conditions during ripening and storage. Cheese is a niche product having high market demand however due to loss of product to spoilage during the distribution chain, the market is limited to the regions of its origin. Conventional cheese packaging method consist of vacuum packaging and gas flushing methods, however this method has its limitations leading to off flavor, discoloration, toxin compounds due to exposure to light by the transparent packaging material (I. Arvanitoyannis & Tziatzioa, 2012). There is a change in consumer preferences in food; increased demand for quality, safe, minimally processed food and cost effectiveness, which could no longer be fulfilled by the conventional packaging (Ahvenainen, 2003). In addition, the traditional concept of passive packaging of food has changed to newer focus of active packaging materials in food (Biji, Ravishankar, Mohan, & Srinivasa Gopal, 2015; Karaman et al., 2015). Thus, efforts have to be put into newer packaging methods in different food including cheese to meet the changing consumer demands. Therefore, this assignment mainly focuses on the new packaging systems available in different varieties of cheese because of its high susceptibility to spoilage and traditions associated with cheese production. 2.0 Different packaging types and systems Packaging consists of namely three different types, primary package; main frontline of barrier for the product, if breached leads to quality deterioration and spoilage of the products, the package comes in direct contact with the product. Secondary package; the primary package is placed inside the secondary package during storage and distribution for protection and ease of handling of the product. Tertiary package; encloses the secondary package for the purpose of ware house storage and long duration transport during shipment of the products. Karaman et al. (2015) states that the different packaging types and systems for dairy products is derived from both the industry and consumer point of view such as the product type, cost effectiveness, distribution channel and storage, the consumers preference and convenience and the proposed end use of the product like for example in retail sliced cheese packaged in flexible films and aluminum foils. A package is “active” when it provides more than the traditional function of protection from physical elements, like enhancing shelf life through changes in the package conditions while maintaining the product quality through several approaches like oxygen scavengers, temperature and moisture control and addition of active compounds like chemicals (Biji et al., 2015). Moreover, a package is “intelligent” when it monitors the condition of the package and providing information on the quality of the product during storage and distribution such as time-temperature indicators, gas leakage indicators, toxin indicators and freshness indicators. (Coating and intelligent). The effectiveness of the above mentioned systems are dependent on the type of dairy products and have found to be very significant in the preservation and prolonging the shelf life of various dairy products including cheese. Packaging system in cheese Packaging materials primary role is protection of cheese against external contaminants mainly microorganisms like in any other dairy products and also according to Cerqueira et al. (2010) packaging influences the functional properties like, exchange of volatile gases and moisture from cheeses during ripening which is essential in formation of desirable cheese flavors. However, the role of packaging in providing desired functional properties acceptable by consumers is different for each specific type of cheese product. Packing material in cheese mostly includes, flexible film laminates, such as ethylene vinyl alcohol (EVOH), nylon, aluminum foil (Karaman et al., 2015). Soft cheese and cream cheese is more susceptible to photo oxidation due to its high moisture and fat content, hence requires use of light barrier compounds like TiO2 in the packaging material. The main spoilage causing agent in cheese making is contamination of spoilage microorganisms, and release of detrimental enzymes by spoilage microorganism resulting in lipolysis and proteolysis, thus there is a need of other control mechanisms of these spoilage agents in enhancing the shelf life of cheese products other than traditional means of heating milk during processing. Rooney (1995) states that it is rare for the cheese manufacturers to change procedure of cheese making due to traditional values associated with cheese making, therefore to prolong the shelf life of cheese focus is made on innovations in packaging material. Following are some of the active packaging technologies applied in the preservation of different cheese varieties. Active coatings and compound According to Karaman et al. (2015) edible coatings film made from polysaccharides, lipids, protein are used as an extra coating in addition to traditional packaging to enhance preservation of cheese without influencing the sensorial qualities in the cheese products. Cerqueira et al. (2010) showed the use of edible coating from galactomanan and chitosan in effectively reducing the moisture loss, weight loss, discoloration, hardness and reduction on the growth of total mesophilic bacterial count in semi hard cheese at both test temperatures of 4oC and 20oC. Chitosan is a polysaccharide known to have antimicrobial properties and has many applications in food, agriculture, medicine (Karaman et al., 2015) and is relatively cheaper and environment friendly (Altieri, Scrocco, Sinigaglia, & Del Nobile, 2005). The distinguishing properties of chitosan is found to be the study of interest by many researcher. The effect of chitosan as an active compound was evaluated on the shelf life of mozzarella cheese by Altieri et al. (2005), whey prepared lactic acid/chitosan solution of 0.075% concentration was directly added to milk with starter culture during processing. They found that chitosan inhibited the growth of spoilage microorganisms such as coliforms and Pseudomonas spp. With no effect on the growth of starter culture under refrigeration conditions. With growing concerns on the impact of plastic wastes to the environment and international leaders collaborating in mitigating this environmental issues. One way of confronting such issues is through application of biodegradable materials. Poly lactic acid (PLA) is a biodegradable thermo plastics made from corn starch or sugar cane and is used in the packaging of food requiring low water vapor barrier properties. Thus, the use of this poly lactic acid film barrier properties was investigated in Danbo cheese a semi hard cheese variety, exposing packaged cheese to dark and light to simulate storage conditions. The result successfully demonstrated the use of PLA in protection of Danbo cheese from moisture loss and lipolysis for a period of 56 days and 84 days during exposure to light and dark respectively. Active Antimicrobial agents The application of antimicrobial agents in packaging as the name indicates is aimed at destruction of spoilage bacteria in the cheese product. According to Sinigaglia, Bevilacqua, Corbo, Pati, and Del Nobile (2008) presence of coliform in dairy products is an indication of poor sanitary conditions during processing, coliforms causes swelling in cheese due to release of CO2 during storage, hence can predict the shelf life of mozzarella. Mozzarella cheese is a traditional product of Italy with unique characteristics of melting and stretching into fibrous structure when heated. Mozzarella is a mild soft cheese containing high moisture content. With increased consumers demand in safe and healthier products and in the perspective of cost effectiveness form the manufacturer’s side has lead researchers to search in areas using natural active compounds in packaging material for preservation. In one of the studies conducted by Conte, Scrocco, Sinigaglia, and Del Nobile (2007) successfully demonstrated the use of lemon extract of different concentrations in preventing the growth of spoilage microorganisms without any detrimental effect on the sensorial properties. Mozzarella cheese it is generally placed in brining solution after processing in order to extend the shelf life of cheese, however the shelf life of the product is very short, approximately 5 to 7 days (Altieri et al., 2005; Conte et al., 2007). Sinigaglia et al. (2008) explored the use of active substances like lysozyme and ethylenediaminetetraacetic disodium salt (Na2-EDTA) in the brining solution which resulted in reduction of spoilage coliform and Pseudomonas in the mozzarella cheese. Metallic compounds like silver, copper oxide and zinc oxide are known to have a high anti-microbial property. The use of these metallic compounds in low density poly ethylene (LDPE) as antimicrobial agent was studied in ultra-filtered cheese (UF) using different ratios of the metal at refrigeration temperature, the composition of 0% silver, 1% copper oxide, 0% zinc oxide nanoparticle in LDPE polymer effectively reduce coliform by 4.21 log cfu/g in cheese as compared to 1.04 log cfu/g in pure LDPE film, with no migration of nanoparticles, toxicity into cheese (Beigmohammadi et al., 2016). Natamycin is used in food industry as a natural preservative to inhibit growth of mold and fungi. The use of biodegradable films made from triticale flour incorporated with natamycin of different concentration as an active packaging material was evaluated in soft cheese. Natamycin was added into film forming solution during film preparation to get a concentration of 5 mg natamycin/ dm2 film, 10 mg natamycin/dm2 film and 20 mg natamycin/dm2 film. Natamycin did not affect the barrier properties of triticale film and significantly retarded the growth of A. niger and the inhibition effect of C. albicans increased as the concentration of natamycin increased in soft cheese (Romero, Borneo, Passalacqua, & Aguirre, 2016). According to Matteo Alessandro Del Nobile and Conte (2013), essential oil of plant origin is said to have antimicrobial properties to wide range of bacteria and fungi. Cellulose acetate films incorporated with pink pepper essential oil demonstrated inhibition of growth of Escherichia coli, S. Typhimurium Staphylococcus aureus, Listeria monocytogenes, in sliced mozzarella cheese and ability of EO to diffuse from the film to the solid agar medium. The application of antimicrobial agents from natural compounds in the packaging systems have the potential to reduce high heat treatment processing and use of chemical preservatives in cheese, however further understanding of use these active compounds is necessary in view of public safety. Modified Atmosphere packaging (MAP) Modified atmosphere packaging is a method in which the internal atmosphere of packaging is changed using different ratios of carbon dioxide (CO2) for preservation of cheese by preventing growth of mold and nitrogen (N2) is used as filler to prevent package collapse. However, CO2 is said to degrade the flavor and affect the starter microorganisms crucial in cheese production. I. S. Arvanitoyannis, Kargaki, and Hadjichristodoulou (2011) studied the influence of MAP on anthotyros cheese a type of whey cheese hydrated to moisture content of 35%. Cheese was stored for 55 days under refrigeration condition, using different types of atmosphere composition, atmosphere of 60% CO2/40% N2 showed remarkable inhibition of E.coli and total viable counts (TVC) with no change in sensory attributes in cheese. Similarly, the effectiveness of modified atmosphere packaging was carried out in Stracciatella cheese a fresh variety of cheese, where four different gas mixtures of CO2:N2:O2 of 50:50:0 (M1), 95:5:0 (M2), 75:25:0 (M3), and 30:65:5 (M4) vol/vol stored at 8° C were used, gas mixture of (M1) and (M2) retarded microbial growth of spoilage bacteria, having no effect on the starter micro flora and the sensory qualities of cheese (Gammariello, Conte, Di Giulio, Attanasio, & Del Nobile, 2009). In contradiction to the above two studies, sliced samosa cheese was packaged in different atmosphere of in 0% CO2:100% N2, 20% CO2:80% N2 and 100% CO2 which was exposed to light and darkness for 3 weeks. Cheese packaged in atmospheres containing 100% CO2 showed a significant discoloration in cheese from yellow to red and development of rancid flavor when exposed to light and also observed drying out effect in cheese stored in both light and darkness. Whereas compared in other two atmospheres the cheese did not show any discoloration and rancidity however slight loss of moisture was detected in both the storage conditions (Juric, Bertelsen, Mortensen, & Petersen, 2003). Thus it can be concluded that the concentration of gas mixture used for MAP has a significant role in preservation of different types of cheese with both beneficial and detrimental effects and is also dependent on storage conditions of these MAP packed cheese products. Further, the efficacy of MAP can be enhanced in combination with other active packaging methods. Fior di latte cheese is similar to mozzarella, popular in southern Italy, high moisture content and fat content contributes to short shelf life of this cheese product. Matteo A. Del Nobile, Gammariello, Conte, and Attanasio (2009) also demonstrated the al=application of chitosan into cheese making, combined with active coating of sodium alginate prepared by mixing sodim alginic acid in lysozyme, ethylenediamine tetra acetic acid EDTA, disodium salt (Na2-EDTA) and gas mixtures of 30:5:65 (CO2:O2:N2) were used and resulted in prolonged shelf life of Fior di latte cheese by 5 days. The combined effect of modified atmospheres consisting of carbon dioxide CO2 30% and nitrogen N2 70% with iron based oxygen scavenger sachets of 50 cc in soft cheese kelko stored under refrigerated temperature, shelf life was extended, good outside appearance and lactic acid aroma was observed. Consumer Acceptance Conclusion Ahvenainen, R. (2003). Novel food packaging techniques. 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