Cellulose shelf life

The synthesis of vinylsulfonyl dyes is a good example for a method to obtain pH indicator layers with operational stability of weeks and shelf life of years. Commercial transparencies with a cellulose coating are used as the polymer matrix and the reactive vinylsulfonyl dye is bound to the cellulose... 

Carrageenans, alginates, polysaccharides, carboxy methyl cellulose etc. Provide mouthfeel, shelf-life stability, viscosity... 

A microdefibrillated suspension of cellulose in water has been reported to have an indefinite shelf-life (Weibel, 1994). 

SEPIFILM 003 and 752 The association of cellulose with a film coating agent was originally patented by SEPPIC. Microcrystalline cellulose is probably one of the most extensively used excipients in pharmaceutical and nutritional products. Unlike other fillers, such as lactose, cellulose is inert, vegetable derived, and accepted worldwide and its shelf life is unlimited. Figure 31 shows the advantage of cellulose microcrystalline in film coating. 

Moisture absorbers. Based on cellulose fibres or a cross-linked polymer hydro gel to remove the drip from fresh meat resulting in a better appearance of the food. In some packaging, mixtures of herbs are added to the absorbing pad to avoid microbiological growth in the drip juice and as a result a longer shelf life. For dry foods, e.g., biscuits, moisture regulators based on silica gel or molecular sieve may be employed. 

These compounds will substantially increase the shelf life of propellant through binding decomposition products like free acid and nitrogen oxides, which are formed during the slow decomposition of the cellulose nitrate. The stabilizer is transformed into relatively stable nitro and nitroso derivatives. 

Uses Crosslinking agent for carboxylated SBR latex, carbor methyl cellulose, PVA, and other water-sol. polymers water resist, aid for starch-based adhesives and coalings food-contact paper/paperboard Regulatory FDA 21 CFR 176.170,176.180 Properties Pale amber liq. water-soL sp.gr. 1.03 vise. 50 cps f.p. -3.9 C pH 4.7 cationic 12.5% total solids Storage 100 days shelf life below 32 C Polycup 1884 [Hercules]... 

Coatings and edible films are used to protect food products and improve their quality and shelf life. There has been a great interest in production of edible films and coatings from biopolymers in recent years. The most widely used edible and biodegradable films are cellulose derivatives. 

A few examples of applications of cellulose edible films or coatings are discussed below. They are used to increase product appearance or conservation (increasing shelf life). 

Highly oxidizable oils such as fish oils can be protected by a process known as microencapsulation, which coats the oil with a matrix of protein (gelatin, casein), carbohydrates (starch, cellulose, carboxymethylcellulose or cellulose derivatives) and lecithin. Microencapsulation provides protection against oxidation and imparts oxidative stability. The use of carboxymethylcellulose and cyclodextrins as coatings is claimed to provide better protection of oils by improved oxygen barrier properties. For special applications as nutritional supplements, fish oils enriched in n-3 PUFA are microencapsulated, in the presence of antioxidants, into a powder that is relatively stable at ambient temperatures. However, encapsulated fish oils can impart undesirable fishy taste when incorporated into food emulsions. More research and development is needed to evaluate potential applications and benefits of active packaging to increase the shelf life of fish oils and other highly oxidizable oils in foods. 

The properties listed in Table 5.8 were responsible for the rapid replacement of cellophane or other cellulose-based packaging materials by polyethylene. Utilizing polyethylene in food packaging applications, such as fresh produce, provided much longer shelf-life and a reduction in waste and spoilage. As can be seen from the physical properties of polyethylene relative to cellulose, polyethylene was more elastic, less likely to tear, heat sealable and much less permeable to water vapor. 

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