Effects of Season and Processing on Oil Content and Fatty Acids of Baltic Herring (Clupea harengus membras)

Abstract

Fatty acid composition, oil content, free fatty acid content, and peroxide value of Baltic herring (Clupea harengus membras) and two processed products (fried fillets and fish burgers) were investigated. The highest oil content of the fillets was found in autumn (10%), at the time when the free fatty acids had their minimum (1.4%). The main fatty acids were oleic (18-23%), palmitic (17%), palmitoleic (8-12%), and docosahexaeneoic (8-10%) acids. The proportion of saturated fatty acids was a constant 23% all year around, whereas mono- and polyunsaturated acids varied from 34 to 39% and 33 to 37%, respectively. During processing the oil content doubled and the fatty acid composition changed to the pattern of the rapeseed oil used for frying. Oleic acid was a major fatty acid in the products comprising over 40% of the total fatty acids. The proportion of n-3 acids decreased during processing but the total amount of polyunsaturated acids remained fairly constant.

Effects of pan-frying in margarine and olive oil on the fatty acid composition of cod and salmon

“…Several studies were undertaken to determine the effects of different cooking methods on the fatty acids of fish species, in particular deep fat-frying and oven-baking (Agren & Hanninen, 1993;Aro et al, 2000;Candela, Astiasaran, & Bello (1997, 1998 ;Gall, Otwell, Koburger, & Appledorf, 1983;Mai, Shimp, Weihrauch, & Kinsella, 1978;Mustafa & Medeiros, 1985;Sanchez-Muniz, Viejo, & Medina, 1992). Yet, less information on the effect of pan-frying can be found.…”

Fish Lipids as a Source of Healthy Components: Fatty Acids from Mediterranean Fish

“…The same observation was made for D. sargus captured along the eastern Mediterranean coast of Turkey (Ozyurt et al, 2005;Imre & Saglik, 1998). The seasonal changes in the contents of these fatty acids were previously recorded for gilthead sea bream (Sparus aurata) (Grigorakis et al, 2002), for Baltic herring (Clupea harengus membras) (Aro et al, 2000), and some other fish species (Luzia et al, 2003;Tanakol et al, 1999). Furthermore, observations regarding the seasonality of fatty acid composition in D. vulgaris caught in other areas of the Mediterranean Sea that were previously published (Donato et al, 1984) …”

Incorporation of medium chain fatty acids into fish oil triglycerides by chemical and enzymatic interesterification

“…The total n-3 fatty acid content in the original ROPUFA ® fish oil was 31.92 %, with a predominance of EPA and DHA, and no MCFA was identified in this sample. Such a composition is a characteristic feature of marine oils (Pigott and Tucker, 1990;Aro et al, 2000). Capric and caprylic acids were responsible for more than 98% of the Trigliceril CM ® fatty acid composition.…”