Free‐choice flavour and odour profiling of fish spoilage: Does it achieve its objective?

Abstract

A BS T R A C TFree-choice odour and flavour profiling of fish spoiling under diflerent regimes leads to a wide range of descriptors which are difjicult to collate and quantify. An attempt was made to gain an insight into the spoilage process by applying a variety of analytical techniques to the profile data including cluster analysis, principal coordinates analysis and especially generalised Procrustes analysis. However, it was concluded that manipulation of 9 e echoice profiles does not provide any additional information about the spoilage of fish that cannot be obtained from analytical taste panels, simple chemical tests and a cursory examination of the profiles themselves.

Sampling of potato tubers – a method based on a mathematical interpretation of gross potato tuber anatomy

“…I t has been shown, however, by Wilson & Lindsay (1969), and discussed by Quarmby & Ratkowsky (1972), that the relationship between solids* or dry matter* and SG in vegetative tissue, is only near-linear and the true linear relationship lies between DM and the reciprocal of SG or specific volume (SV).…”

“…All experimental work was carried out at constant temperature (20°C), and weighings in air and water were made on a top pan balance reading to 10 mg. Before use, all weight data were corrected for air buoyancy. , 1969;Quarmby & Ratkowsky, 1972) then And so if the first part of the intratuber DM concentration gradient is considered linear (profile A, Fig. 2), then the first part of the SGI gradient must be non-linear (profile B, Fig.…”

“…Two well-shaped medium sized tubers from each of the three varieties Sebago, Brownell, 9-1 (unnamed) and two each from two different lots (0 & N) of Kennebec (a total of ten tubers), were selected from the current season's crop and concentrically peeled according to Quarmby & Ratkowsky (1972). The major features of the ten experimental tubers are given in Table 1.…”

“…The data presented in this paper are the partial result of concentric peeling experiments (Quarmby & Ratkowsky, 1972) carried out during the development of a sampling technique whereby tests, especially specific gravity (SG) determinations, made on small tissue samples, could be transformed to values representative of the tuber from which they were taken.…”

Seafoods: Chemistry, Processing Technology and Quality

“…This technique has been applied to fish products by several workers at the Seafood Technology group of the CSIRO. Quarmby and Ratkowsky (1988) used the method to evaluate the process of fish spoilage in a comparison of the use of onboard handling of gemfish. Analysis of the terms chosen by each assessor showed that the first principal component was essentially an acceptability axis as the descriptors showed association with spoiled fish odours.…”