Frozen minced fish, which is commonly referred to as “frozen surimi”, is typically produced by the process in which fish meat, such as pollack, is firstly minced, the minced fish is subjected to two or more washes with fresh water to remove undesirable fish odours, a small amount of common salt is added to the fresh water in the final wash step, the skin is removed where necessary, a screw-press is used to remove water from the product, sugars or sugar alcohols are mixed with the dried product and, finally, the product is packed and stored under refrigeration at −20° C. to −40° C.
One problem with this process is that the repeated washing steps remove not only undesirable flavours but also many of the desirable flavours. Therefore, replacement flavours must typically be added back into the surimi to achieve the desired flavour profile.
Flavour compositions that can be used for adding back the desired flavour profile contain dimethyl sulphide (referred to herein as “DMS”) as a major component because it delivers a desirable sulphury, vegetal, crab-like top note.
However, DMS is a volatile component that evaporates undesirably quickly upon storage such that product containing it lose a significant part of the crab-like tope note.
Additionally, DMS is often incompatible with various other ingredients used for adding back flavour into surimi products. This results in the presence of an undesirable film, comprising the DMS, which is visible on the surface of the flavour composition.
One approach to stabilize DMS in surimi products is to generate an emulsion of the DMS, which is hydrophobic, with certain hydrophilic ingredients. However, emulsions are intrinsically unstable, especially upon storage over longer periods and/or at elevated temperatures and, once the emulsion separates, the known problems identified above can recur.
Furthermore, emulsion manufacture is often an expensive and time-consuming process requiring harsh processing conditions, such as high pressure, high shear or both This is undesirable since the large amount of heat generated by such processing risks driving off the volatile DMS component.
Thus, it is an objective of the present invention to address one or more of the abovementioned problems and/or to provide one or more consumer desirable benefits.
We have now found that the addition of certain cellulose ether derivatives at the correct dosage can address one or more of these problems.
The use of hydroxypropyl methyl cellulose has been described in “Surimi and Surimi Seafood”, Second Edition by Jae W. Park, publisher: Food Science and Technology) as an ingredient which can improve the texture of surimi. However, this requires very high levels of the ingredient. In the present invention, much lower levels of the cellulose ether derivative are required in order to stabilise the flavouring composition comprising DMS.
In U.S. Pat. No. 5,958,502 (Fulger et al), there is described a process for incorporating a volatile component into a matrix. The volatile component can be any component having a low boiling point, such as DMS and the matrix can be selected from a large number of materials, including cellulose ether derivative. The product is a glassy carbohydrate matrix and there is no disclosure or suggestion of using DMS together with a specific cellulose ether derivative.
In Pangborn R M et al., Journal of Texture Studies, vol. 4, No. 4, 1974, pages 467 to 482, table 1 on page 468 discloses a composition comprising, amongst other ingredients, DMS and hydroxpropylcellulose. The amount of DMS is at most 0.0006 g/100 ml water, which is far below the amount used according to the present invention.