Food crispness

Srisawas, W. and Jindal, V.K. Acoustic testing of snack food crispness using neural networks, /. Texture Stud., 34, 401, 2003. 

P. A. Fenner-Crisp, "Risk Assessment Methods for Pesticides in Food and Drinking Water," Office of Pesticide Programs, U.S. Environmental Protection Agency, presented at the Florida Pesticide Review Council Meeting, July 7, 1989. 

Sucrose is widely used in the food industry to sweeten, control water activity, add body or bulk, provide crispness, give surface glaze or frost, form a glass, provide viscosity, and impart desirable texture. It is used in a wide variety of products from bread to medicinal symps. 

Xanthan gum is used as a thickener in sauces, as an agent in ice cream that prevents ice crystals from forming, and as a fat substitute that adds the mouth feel of fat without the calories. It is used in canned pet food to add cling. In pastry fillings, it prevents syneresis (weeping of the water in the filling), protecting the crispness of the crust. 

Nylon barrier layers are used in packaging films and blow molded bottles. In these applications, their excellent resistance to oxygen permeation are valued when packaging greasy foods, such as potato crisps (chips), that rapidly turn stale when exposed to oxygen. 

Rye will grow under much harsher conditions than wheat. In Germany and Scandinavia rye breads, either wholly rye or mixed with other grains, are eaten. In the UK, rye is little used and the somewhat bitter flavour that it imparts is in general not appreciated. The small amount of rye used is deployed in health food products, crisp breads and in making rye products to satisfy foreign tastes. 

The term biscuit now covers a whole range of products, even including pet foods. The crisp savoury products known as crackers are considered as biscuits while wafers are not biscuits. 

Once in the amorphous solid state, undesirable changes in the properties of amorphous ingredients and foods (e.g., stickiness, caking, collapse, loss of crispness) can occur via a reversal in the two events discussed earlier (1) an increase in moisture content (water plasticization) so that the Tg of a material is decreased to below room temperature and (2) an increase in temperature [thermal plasticization (Roos, 2003)] so that the temperature of the material rises above its Tg. In both cases and their combination, the once glassy material is now in a rubbery or liquid state and is undesirable and/or unfit for consumption. 

Roudaut, G., Dacremont, C., and Le Meste, M. 1998. Influence of water on the crispness of cereal foods Acoustic, mechanical, and sensory studies. J. Texture Stud. 29, 199-213. 

In practice this means that BHT can be present at up to 100 mg/kg in the fat fraction of manufactured foods such as baked goods and fried foodstuffs such as potato crisps or fried chicken. Although higher levels are permitted in chewing gum and dietary supplements, these might be expected to have a lesser impact on intakes because of the relatively small amounts of such foods consumed. 

It also appears that traditional forms of food processing may not be as safe as expected. The example of the formation of acrylamide in different heat-processed foods may be cited (see Chapter 13 of this volume). However, there are no incontrovertible answers to the questions is acrylamide in food harmful for consumers , and what is the average intake The American Council on Science and Health states that there is no credible evidence that acrylamide in foods poses human cancer risk. New Zealand food safety experts, using a no observable adverse effect level for acrylamide of 0.1 mg per kg bodyweight, also estimate that people eating fried potatos and crisps (products suspected to contain the largest amounts of acrylamide) are a very low risk of cancer from this source. European Union experts decided that the risk of exposure to polyacrylamide in food remains undetermined (Sharp, 2003). 

Trans fatty acids are produced during the commercial hydrogenation of plant oils (Chapter 11). Some margarines contain these fatty acids, as do some commercially prepared snack foods (e.g. biscnits, cookies, cakes, crisps, chips). In addition, bacteria in the rnmen of rnminants prodnce trans fatty acids, which are therefore present in dairy prodnce and meat. Trans fatty acids can be incorporated into the phospholipids of the plasma membrane of endothelial and other cells, resulting in damage to the membranes. Furthermore, these abnormal fatty acids can interfere in the production of thromboxanes, prostacyclins or leucotrienes and hence interfere in control of blood clotting, immune cell activity and inflammation (Chapter 11). 

Gamble, M. H. and Rice, P. (1988). The effect of slice thickness on potato crisp yield and composition. ]. Food Eng. 8, 31-46. 

Nowadays potato is one of the major food crops in the world. Heavy yields can be grown relatively cheaply in a wide variety of soils and climates, and potatoes are one of the mainstays in the diet of people in many parts of the world. In 2005 total EU 25 (Europe of the 25) potato production reached 58 848 0731, with yields of 29.2 t/ha and a cultivation area of 1 985 358 ha (British Potato Council, 2007). Thus, potato processing and potato products are popular and acceptable throughout Europe. Figure 7.1 shows the 2005 production and external trade in processed potatoes for the European Union (25 countries). The main item is frozen potatoes, including prefried, at 3 414 9311, followed by potatoes prepared or preserved as potato chips or crisps, 1 647 9501 dried potatoes in the form of flour, meal, flakes, granules, and flakes, 280 3771 potatoes prepared or preserved in the form of flour, meal, or flakes (excluding frozen, dried, crisps), 207 0371 and 18 9861 of dried potatoes not further prepared (Eurostat, 2005). Frozen potato products account for more than 61% of all potatoes that are processed, crisps for... 

In April 2002, Swedish researchers shocked the food safety world when they presented preliminary findings of acrylamide in some Ified and baked foods, most notably potato chips and French fries, at levels of 30-2300 p,m/kg. Reports of the presence of acrylamide in a range of fried and oven-cooked foods have caused worldwide concern because this compound has been classified as probably carcinogenic in humans with significant toxicological effects, namely neurotoxic and mutagenic (Rosen and Hellenas, 2002 Tareke et al., 2002). French fries and potato crisps exhibit relatively high values of acrylamide 424 p-g/kg and 1739 p-g/kg, respectively. 

The value of potatoes in nutritional management may depend on other food components which contribute to the composition of the form of potato consumed. For instance, Ified potatoes in the form of potato crisps (Table 13.2) contain a high proportion of fat, and very little water, so on an equal weight basis they are about six times more energy-dense than potatoes alone. However, that has little to do with potatoes, but is more a result of the way they are treated. 

Caldwell, J. (1992) Problems and opportunities in toxicity testing arising from species differences in xenobiotic metabolism. Toxicol. Lett., 64/65, 651-659 Caldwell, J., Anthony, A., Cotgreave, I.A. Sangster, S.A., Sutton, J.D., Bernard, B.K. Ford, R.A. (1985) Influence of dose and sex on the disposition and hepatic effects of cinnamyl anthranilate in the B6C3F1 mouse. Food chem. Toxicol., 23, 559-566 Cattley, R.C., DeLuca, J., Elcombe, C., Fenner-Crisp, R, Lake, B.G, Marsman, D.S., Pastoor,... 

T Asap, MA Augustin. Effect of frying oil quality and TBHQ on the shelf-life of potato crisps. J Sci Food Agric 37 1045-151, 1986. 

Nitrogen In the production of ammonia by the Haber process (see p. 176) the ammonia is then used to make nitric acid, which is used in the manufacture of dyes, explosives and fertilisers In liquid form, as a refrigerant As an inert atmosphere for some processes and chemical reactions, because of its unreactive nature for example, empty oil tankers are filled with nitrogen to prevent fires In food packaging to keep the food fresh, for example in crisp packets where it also prevents the crisps being crushed (Figure 11.10)... 

The extent of contact is also important and it can be expressed as the ratio of food weight to contact area. An example is the situation where a film is used to pack a solid food like potato crisps which make only point-contact with a limited area of the film. Clearly, in this case the potential for migration is less than if the same film was used in more intimate contact with a food - for example if it were used to vacuum-pack a food item. Even if the food contact is intimate with a liquid or semi-solid food, there can still be large differences in the food mass to contact area ratio. Common examples would be an individual portion pack of margarine or butter (say, 7 g in contact with 28 cm2, or 4000 cm2/kg) compared with a catering pack of the margarine or butter (say, 2 kg in contact with... 

This buttery, crisp shortbread can be flavored in so marry ways with herbs from the farmers market (rosemary, lemon verbena, sage), with lavender, with crystallized ginger. After visiting a boutique in Paris that makes all its sweet and savory foods with infusions of tea,... 

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