Solid food industry

Agar occurs as a cell-wall constituent of the red marine algae Rho ophyceae, from which it is extracted by hot water, and marketed as a dry powder, flakes, or strips. It dissolves in hot water and sets on cooling to a jelly at a concentration as low as 0-5%. Its chief uses are as a solid medium for cultivating micro-organisms, as a thickener, emulsion stabilizer in the food industry and as a laxative. 

Shelf Devices Equipment having heated and/or cooled shelves is available but is httle used for divided-sohds heat processing. Most extensive use of stationaiy shelves is freezing of packaged solids for food industries and for freeze drying by sublimation (see Sec. 22). 

The complexity of the problems associated with future food packaging can be seen from these examples. We have focused on only one factor in one segment of the food industry—the effect of change in solid waste disposal. The present uncertainties in technical and political aspects of the disposal problem prevent a definite decision as to whether packaging changes should be made. All the industry can do at present is prepare itself for a possible major shift that would have to be made in a short time. 

This reaction is used in the food industry to convert vegetable oils into shortening (Fig. 18.12). Oil and solid fat molecules both have long hydrocarbon chains, but... 

Since, the pineapple canning industry is one of the many food industries producing large quantities of solid and liquid wastes and due to the stringent environmental regulations regarding to waste disposal a special interest has developed in using the pineapple waste. 

TKPP (K4P2O7) is a merchant chemical produced by many major companies throughout the world. It is available commercially as a free flowing, white, grsr.ular solid or as a 60% wt. solution. In addition to its widespread use in the liquid detergent formulations, TKPP is also utilized in the food industry. It has been certified by the U. S. Department of Transportation as nontoxic. The solubility of TKPP in water at 60° F is shown in Table I. It is possible to achieve increased density at temperatures above 60° F because of increased solubility. 

As most sensors are limited to single point probing, their application is confined to samples where the investigated point(s) are representative for the sample. Though this is the case for the majority of fluid samples, solid objects may not fulfil this requirement. This is true for high-tech products containing a wide range of different materials as well as e.g. in the food industry, where an item that is analysed as edible at one spot may very well be rotten at a different one. 

The freeze drying of coffee extracts has been, and still is, the most frequent application of this process in the food industry. For economic reasons it is best to start with 40 % solid content in the extract. The final product is judged by the following criteria ... 

The relationship between the refractive index and the amount of dry substance content is well known for sucrose and is the basis for the degree Brix (°Brix) scale. It is arbitrarily set such that 1° Brix is equal to a concentration of 1% sucrose. In other words, the °Brix scale indicates the number of grams of sucrose per 100 g of solution. This relationship also holds for a large number of similar substances and finds extensive use in the food industry. For example, a reading of 40° Brix would mean that the sample contained 40 g of solid per 100 g of solution. 

You may find the term hydrogenation familiar. Some food products, such as margarine and peanut hutter, contain hydrogenated vegetable oils. Hydrogenation is used in the food industry to convert liquid vegetable oils, which contain carbon-carbon double bonds, to solid fats, such as shortening, which are fully saturated. 

Bauer, W. and Kunz, B., Solid-state fermentation in food industry, in Chmiel, H., Hammes, W.P. and Bailey, J.E., (eds.). Biochemical engineering, Gustav Fischer Verlag, Stuttgart, 1987, 228-241. 

Carbon dioxide is a gas at room temperature. Below -78°C it is a solid and is commonly referred to as dry ice. At that temperature it sublimes and changes directly from a solid to a vapor. Because of this unique property, as well as its non-combustible nature, it is a common refrigerant and inert blanket. Table 3.4 shows the uses of carbon dioxide in all its forms liquid, solid, and gas. Refrigeration using dry ice is especially important in the food industry. Beverage carbonation for soft drinks is a very big application. In oil and gas recovery carbon dioxide competes with nitrogen as an inert atmosphere for oil wells. 

Spray-drying is an economical effective method widely used for flavour encapsulation [22-27]. The technology has been used in the food industry since the late 1950s to provide protection of aroma chemicals against oxidation or degradation and to convert liquids into free-flowing solids. The main limitations... 

One of the oldest production methods for the production of dry flavours is the plating of a liquid flavour or extract onto a solid carrier. Carriers of main importance for the food industry are salt, lactose, starch and maltodextrin [64]. 

Flavor Release. Encapsulated flavors find uses throughout the food industry. One major example would be beverage dry mixes. Maltodextrins and corn syrup solids have excellent cold water solubility, so their use in encapsulated flavors will provide a rapid release of flavors used in beverage applications. Maltodextrins and low DE corn syrup solids also have very little flavor or sweetness of their own, form clear solutions, and virtually disappear once in an application. 

Extraction using a supercritical fluid (CO2, N20 or CHC1F2 Freon-22) is a well-known process in the food industry (cf. 6.1). Extractors used for analytical purposes operate on the same principle. They incorporate a highly resistant tubular container into which the sample is placed (in solid or semi-solid form) with the supercritical fluid. Two modes of operation are employed ... 

Crystalline D-fructose also finds use in the food industry. The annual consumption, in the United States, of dextrose is >600,000 tons and of HFCS >8,000,000 tons (71% solids basis). 

Pectins are readily soluble in water to give viscous stable solutions. However, the importance of pectin to industry, in particular the food industry, is the ability of its solutions to form gels with sugar (ca 65% solids) and acid or calcium ion under suitable conditions (51). 

The extent of oxidative deterioration will determine the acceptability of a food product. Because of this, methods for determining the degree of oxidation are very useful to the food industry. There are many possible methods that can be utilized (see Commentary) however, due to the stability of some of the end products, and their direct relationship with rancidity, headspace GC provides a fast and reliable method for oxidation measurement. Headspace techniques include static, dynamic, and solid-phase microextraction (SPME) methods. 

In the food industry it has often been difficult to obtain true viscosity measurements (unithj.j) of complex fluid foods such as coarse fruit suspensions. These are usually non-Newtonian suspensions. Fruit concentrates are dispersions of solid particles (pulp) in aqueous media (serum). Their rheological properties are of interest in practical applications related to processing, storage stability, and sensory properties. Expensive rheometers are often not available in quality control and product development laboratories. However, viscosity is nonetheless an important quality factor of these products. 

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