Starch food applications

Starch is isolated from plant sources by various methods (Ratnayake and Jackson, 2003 Zobel, 1992). The method of starch isolation depends on the nature and composition of the raw material source. Most food starches are isolated and purified on a commercial scale and then used as ingredients by food manufacturers. Commercial food starches are generally classified based on both botanical origin and functionality. With the increasing availability of modified starches prepared for specific food applications, starch manufacturers tend to emphasize and market starch with a secondary focus on botanical source. In fact, for food... 

Modification, which involves the alteration of the physical and chemical characteristics of the native potato starch to improve its fimctional characteristics, can be used to tailor it to specific food applications. The rate and efficacy of any starch modification process depend on the botanical origin of the starch and on the size and structure of its granules. This also includes the surface structure of the granules, which encompasses the outer and iimer surface depending on the pores and channels, which cause the development of the so-called specific surface (Juszczak, 2003). Potato starch modification can be achieved in three different ways physical, conversion, and chemical (derivatization) (Table 10.6). 

Singh, J., Kaur, L., McCarthy, O. J. (2007). Factors influencing the physico-chemical, morphological, thermal and rheologieal properties of some chemically modified starches for food applications - A review. Food Hydr., 21, 1-22. 

Edible film and coating is defined as a thin, continuous layer of edible material used as a coating or as a film placed between food components to provide a barrier to mass transfer (Balasubramaniam et al., 1997 Guilbert et al., 1997). These films/coatings have the potential to replace conventional packaging in some applications. Starches such as potato starch, cellulose... 

The sweetness of fmctose is enhanced by syneigistic combinations with sucrose (12) and high intensity sweeteners (13), eg, aspartame, saccharin, acesulfame K, and sucralose. Information on food application is available (14,15). Fmctose also reduces the starch gelatinization temperature relative to sucrose in baking applications (16—18). 

Although most seeds contain starch as the principal food reserve, many contain other polysaccharides and some have industrial utility. The first seed gums used commercially were quince, psyllium, flax, and locust bean gum. However, only locust bean gum is still used, particularly in food applications quince and psyllium gums are only used in specialized applications. 

Starch is an abundant, inexpensive polysaccharide that is readily available from staple crops such as com or maize and is thus is mostly important as food. Industrially, starch is also widely used in papermaking, the production of adhesives or as additives in plastics. For a number of these applications, it is desirable to chemically modify the starch to increase its hydrophobicity. Starch modification can thus prevent retrodegradation improve gel texture, clarity and sheen improve film formation and stabilize emulsions [108], This may, for example, be achieved by partial acetylation, alkyl siliconation or esterification however, these methods typically require environmentally unfriendly stoichiometric reagents and produce waste. Catalytic modification, such as the palladium-catalyzed telomerization (Scheme 18), of starch may provide a green atom-efficient way for creating chemically modified starches. The physicochemical properties of thus modified starches are discussed by Bouquillon et al. [22]. 

Starch, in general, is used in a number of non-food applications.589-596 Worldwide, the majority of wheat starch is sold in unmodified form to manufacturers of paper,... 

Table 12.8 Specification of chemically modified starch for food applications according to Thai regulations... 

Rye starch has been tried as a gelling and thickening agent in the food industry and also in non-food applications.12 Rye starch can be substituted for potato starch. A combination of rye starch and lipids has been used in dessert mixes.16... 

In 2006, Stanelco announced that it had developed a potentially new application area for biodegradable polymers, a cigarette film made from food grade starch that will decompose in two months. 

While biodegradable polymers may be similar to petrochemical-based thermoplastics in terms of their structure, their chemical structure imbues them with technical properties that make them perform in different ways. For example, starch blends can produce film with better moisture barrier protection and higher clarity than some conventional plastics. PLA has a high water vapour transmission rate, which is beneficial for fresh food applications where it is important that the water vapour escapes quickly from the packaging. PLA also reduces fogging on the lid of the packaging. 

Functional food applications where higher choline content is desired Baked goods, starch based sauces, puddings... 

Starches have been chemically modified to improve their solution and gelling characteristics for food applications. Common modifications involve the cross linking of the starch chains, formation of esters and ethers, and partial depolymerization. Chemical modifications that have been approved in the United States for food use, involve esterification with acetic anhydride, succinic anhydride, mixed acid anhydrides of acetic and adipic acids, and 1-octenylsuccinic anhydride to give low degrees of substitution (d.s.), such as 0.09 [31]. Phosphate starch esters have been prepared by reaction with phosphorus oxychloride, sodium trimetaphosphate, and sodium tripolyphosphate the maximum phosphate d.s. permitted in the US is 0.002. Starch ethers, approved for food use, have been prepared by reaction with propylene oxide to give hydroxypropyl derivatives [31]. 

In 1886 the use of malted barley flour was mentioned for use in breadmaking. The enzymes in the malt converted starch into sugars which could serve as yeast substrate during fermentation. Almost 50 years later, the use of a purified enzyme (lipoxygenase) was described for bleaching the cmmb of bread. Since then enzyme usage has become widespread in food applications. 

Unlike starch, waste paper has no human food applications. 

Neo-amylose is suited for food and non-food applications. Due to its resistant starch properties it is suited for use as dietary fiber [139]. Beside this food application, smooth spherical microparticles with a size of 10-100 pm are accessible by recrystaUization of Neo-amylose in dimethylsulfoxide (DMSO). These are suited as cosmetics additive in creams, lotions, or as UV-reflectors [140]. Furthermore, Neo-amylose has proved to be an advantageous constituent in hard or soft films in order to generate gelatin free capsules [139]. 

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