Off-Flavors of Dairy Products

Quality control of raw cows’ milk by headspace analysis

“…In the sterilized milk samples, the highest amount of volatile components was found; up to 77 (Valero et al, 1999(Valero et al, , 2001. During sterilization of milk, volatile components are formed (Azzara & Campbell, 1992;McSweeney et al, 1997). Because we analyzed fresh raw milk samples, these components were not detected.…”

“…Cows' diet, microbiological and chemical contamination, as well as enzymatic deterioration may change the volatile composition of raw milk (Azzara & Campbell, 1992;Shipe et al, 1978). As headspace analysis can detect a whole range of volatile components at the same time, it may be able to detect a wide range of quality defects with a single analysis.…”

Chemical and sensory characterization of oxidative behavior in different wines

“…Changes in wine aroma properties linked to oxidation are very often related to the formation of aldehydes (Azzara & Campbell, 1992;Baró & Quiros, 1977). The role of two aldehydes (methional and phenylacetaldehyde) in wine oxidation process is well known and has been addressed in the literature (Aznar, Lopez, Cacho, & Ferreira, 2003;Escudero, Hernandez-Orte, Cacho, & Ferreira, 2000b;Ferreira, de Pinho, Rodrigues, & Hogg, 2002;Silva Ferreira, Hogg, & Guedes de Pinho, 2003a;Silva Ferreira, Oliveira, Hogg, & Guedes De Pinho, 2003b).…”

Advanced Dairy Chemistry Volume 3

“…an emulsion of fat globules in a colloidal aqueous solution, and a slightly salty and sweet taste, due to the presence of salts and lactose. That there is a real fresh milk aroma is belief rather than fact; because of its blandness, milk certainly is an effective vehicle for offodours (Bassette eta/., 1986;Azzara and Campbell, 1992); because of the lability of some of its components, odorous compounds are readily generated from milk by hydrolysis, oxidation, and enzymatic and microbial activity. The American Dairy Science Association lists the following flavour criticisms: acid, astringent, barny, bitter, cooked, cowy (acetone), feed, fermented/fruity, flat, foreign, garlic/onion (weedy), lacks freshness (stale), malty, oxidized (metal-induced), oxidized (light-induced), rancid (lipolysed), salty, and unclean (psychrotrophic), as well as the corresponding sensory characteristics (Azzara and Campbell, 1992).…”