Organoleptic stability

Figure 15.1 Organoleptic stability of various muguet ingredients in an aerosol antiperspirant after storage at 37 °C for 12 weeks ( VG = very good G = good M = moderate P = poor)...

The organoleptic stability of an ingredient depends on a combination of two factors its sensory characteristics and its chemical stability. The latter, of course, is determined by the nature of the product base. Antiperspirant formulations are acidic because of partial hydrolysis of the active antiperspirant agents, such as aluminium chlorhydrate (equation 1). It is an inorganic salt that consists essentially of complex aluminium chloride described empirically as [Al2(OH)5] .nCl. The complex is polymeric and loosely hydrated. 

Ian Payne, Quest International, for organoleptical stability data of muguet ingredients. Steven Rowlands, Quest International, for analysis of the breakdown products of Lilial in antiperspirant base. 

The organoleptic stability of an ingredient depends on a combination of two factors its sensory characteristics and its chemical stability. The latter, of course, will be determined by the nature of the product base. 

Figure 14.2 Muguet ingredients used in organoleptic stability work...

A common method for determining the stability of pastry, potato chips, and the like is to place a number of broken pieces of the product in 4-ounce mayonnaise jars with screw tops and store them at room temperature or in the Schaal oven in the absence of light. At regular intervals samples are removed and tested for peroxide content and organoleptic rancidity. 

What are they like to eat Humans are particular about the organoleptic properties of their food. Microbial cells may have little taste or smell, or even smell or taste unpleasantly to some people. The texture may not be the same as in conventional foods, particularly with unicellular organisms. These draw-backs can be overcome by adding a proportion of SCP to manufactured foods. However, even when SCP is incorporated into manufactured foods it may not have suitable characteristics such as stability, ability to bind water or fats, or ability to form gels, emulsions or foams. SCP for feed does not have to meet such strict requirements. 

Chaib, J. et al., Stability over genetic backgrounds, generations and years of quantitative trait locus (QTLs) for organoleptic quality in tomato, Theoret. Appl. Genet. 112, 934, 2006. 

New developments are hydroxylamines and lactones (for processing stability), which operate at an earlier stage during stabilisation. Lactone (benzofuranone) chemistry has been identified as commercially viable, and marks a revolutionary advance in comparison to hindered phenols and phosphites [18]. New lactone chemistry (Figure 10.1) provides enhanced additive compatibility, reduced taste and odour (organoleptics), resistance to irradiation-induced oxidation, and inhibition of gas fade discoloration. The commercial introduction of fundamentally new types of stabilisers for commodity and engineering polymers is not expected in the near future. 

Desired organoleptic properties, particularly textural ones, are a direct consequence of these microstructural changes. A chip must be firm and snap easily when deformed, emitting a crunchy sound (Krokida et al., 2001a), whereas in thick products the better the contrast between a rich and soft inner structure and a crispy outside, the better the product (Moreira, 2006). Firmness is often related to starch swelling and gelatinization, as well as to the stability of pectic substances of the cell wall and middle lamellae. 

Another important aspect of encapsulation efficiency is the resistance to oxidation that the carrier imparts to the flavor oils. The oxidation resistance properties are critical to shelf-life stability of the encapsulated product. Oxidation properties can be measured organoleptically by a taste panel or by gas chromatograph of the recovered oil. Peaks related to oxidation products of orange terpenes obtained from GC analysis can be monitored as the powders are aged for three days at 80 C. The GC was used to measure beta-pinene, an oxidation product of orange terpenes. The results are reported in square inches. The greater the area for the beta-pinene peak, the poorer the oxidation resistance of carrier towards the orange terpenes. The data is presented in TABLE 5 ... 

Filtering. Conditioning or lagering gives the beer its desired organoleptic properties, but it still contains yeast, protein-tannin complexes, etc, ie, it has a hazy appearance. A high quality beer must be clear and totally sterile, have colloidal stability, and yeast must be removed to allow the beer to have biological stability. The protein-tannin complexes must also be removed so as not to upset the colloidal stability. 

Com symp solids are also dry products, have a smaller average size, and are comparatively sweeter (12). Both maltodextrins and com symp solids are used to prevent caking enhance dispersibility and solubility provide body or bulk impart desirable texture bind, carry, and protect flavors control extmsion expansion provide viscosity form films and coatings provide an oxygen barrier inhibit crystallization control sweetness improve sheen improve organoleptic characteristics slow meltdown and improve freeze—thaw stability. 

Organoleptic evaluation and product stability are usually assessed by a small expert panel trained to evaluate product appearance and ice cream consistency including smoothness, firmness, creaminess, sandiness, body, icy texture, and other properties. 

A number of sensory tests have so far revealed no difference in the organoleptic properties of ED- and cold-stabilized wines (Bach et al., 1999 Cameira dos Santos et al., 2000 Goncalves et al., 2003 Paronetto et al., 1977 Riponi et al., 1992 Wucherpfennig and Krueger, 1975). 

UF operations are able to produce a juice with a good microbiological stability, preserving organoleptic properties. The clarified juice is then concentrated by OD up to about 60° Brix, maintaining its nutraceutical characteristics [28]. 

These polar transformation products and sulfur oxides (SO2, SO3) arising in the ultimate stages of the transformation process are formed in trace amounts in the aged polymer matrix. Volatile products may be sources of undesirable organoleptic problems. This limits the use of organic thiocompounds in odor-sensitive applications. Organic S-proto-nic acids 85, 86 deactivate basic stabilizers (HAS). The peroxidolytic effect of 85, 86 is reduced in the presence of some antiacids or fillers, e.g., calcium carbonate. 

The addition of NaCl to the aqueous phase is mainly for organoleptic reasons but its effect on caseinate must not be overlooked. Increasing the concentration of NaCl increases the ionic strength without the complications of the strong binding phenomena found with divalent cations. Large changes in the concentration of the univalent cations and their associated anion have a number of important effects on the viscosity of the aqueous phase (Table 9.3) and the stability of the emulsion. The observed small decrease in pH and the increased viscosity of the aqueous system may be related directly. 

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