Effect of fatty acid positional distribution and triacylglycerol composition on lipid by-products formation during heat treatment: I. Polymer formation

Baltic herring (Clupea harengus membras) is one of the most abundant commercially caught fish species from the Baltic Sea. Despite the high content of fat and omega-3 fatty acids, the consumption of Baltic herring has decreased dramatically over the last four decades, mostly due to the small sizes and difficulty in processing. At the same time there is an increasing global demand for fish and fish oil rich in omega-3 fatty acids. This study aimed to investigate enzyme-assisted oil extraction as an environmentally friendly process for valorizing the underutilized fish species and by-products to high quality fish oil for human consumption. Three different commercially available proteolytic enzymes (Alcalase®, Neutrase® and Protamex®) and two treatment times (35 and 70 min) were investigated in the extraction of fish oil from whole fish and by-products from filleting of Baltic herring. The oil quality and stability were studied with peroxide- and p-anisidine value analyses, fatty acid analysis with GC-FID, and volatile compounds with HS-SPME-GC-MS. Overall, longer extraction times led to better oil yields but also increased oxidation of the oil. For whole fish, the highest oil yields were from the 70-min extractions with Neutrase and Protamex. Protamex extraction with 35 min resulted in the best fatty acid composition with the highest content of eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) but also increased oxidation compared to treatment with other enzymes. For by-products, the highest oil yield was obtained from the 70-min extraction with Protamex without significant differences in EPA and DHA contents among the oils extracted with different enzymes. Oxidation was lowest in the oil produced with 35-min treatment using Neutrase and Protamex. This study showed the potential of using proteolytic enzymes in the extraction of crude oil from Baltic herring and its by-products. However, further research is needed to optimize enzymatic processing of Baltic herring and its by-products to improve yield and quality of crude oil.

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Composition and Nutritional Value of Acid Oils and Fatty Acid Distillates Used in Animal Feeding

Animals ◽

10.3390/ani11010196 ◽

2021 ◽

Vol 11 (1) ◽

pp. 196

Author(s):

Elisa Varona ◽

Alba Tres ◽

Magdalena Rafecas ◽

Stefania Vichi ◽

Ana C. Barroeta ◽

...

Keyword(s):

Fatty Acid Composition ◽

Fatty Acid ◽

Acid Composition ◽

Nutritional Value ◽

Oil Refining ◽

Analytical Control ◽

Dietary Energy ◽

Feed Ingredients ◽

Animal Feeding ◽

By Products

Acid oils (AO) and fatty acid distillates (FAD) are oil refining by-products rich in free fatty acids. The objective of this study is their characterization and the identification of their sources of variability so that they can be standardized to improve their use as feed ingredients. Samples (n=92) were collected from the Spanish market and the MIU value (sum of moisture, insoluble impurities, and unsaponifiable matter), lipid classes, fatty acid composition, and tocol content were analyzed. Their composition was highly variable even between batches from the same producer. As FAD originated from a distillation step, they showed higher free fatty acid amounts (82.5 vs 57.0 g/100 g, median values), whereas AO maintained higher proportions of moisture, polymers, tri-, di-, and monoacylglycerols. Overall, the MIU value was higher in AO (2.60–18.50 g/100 g in AO vs 0.63-10.44 g/100 g in FAD), with most of the contents of insoluble impurities being higher than those in the guidelines. Tocol and fatty acid composition were influenced by the crude oil’s botanical origin. The calculated dietary energy values were, in general, higher for AO and decreased when a MIU correction factor was applied. The analytical control and standardization of these by-products is of the outmost importance to revalorize them as feed ingredients.

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Modeling the effect of heat treatment on fatty acid composition in home-made olive oil preparations

Open Life Sciences ◽

10.1515/biol-2020-0064 ◽

2020 ◽

Vol 15 (1) ◽

pp. 606-618 ◽

Cited By ~ 1

Author(s):

Dani Dordevic ◽

Ivan Kushkevych ◽

Simona Jancikova ◽

Sanja Cavar Zeljkovic ◽

Michal Zdarsky ◽

...

Keyword(s):

Heat Treatment ◽

Fatty Acids ◽

Fatty Acid ◽

Olive Oil ◽

Heating Temperature ◽

Virgin Olive Oil ◽

Extra Virgin Olive Oil ◽

Fatty Acid Profiles ◽

Refined Olive Oil ◽

Cross Correlation Analysis

AbstractThe aim of this study was to simulate olive oil use and to monitor changes in the profile of fatty acids in home-made preparations using olive oil, which involve repeated heat treatment cycles. The material used in the experiment consisted of extra virgin and refined olive oil samples. Fatty acid profiles of olive oil samples were monitored after each heating cycle (10 min). The outcomes showed that cycles of heat treatment cause significant (p < 0.05) differences in the fatty acid profile of olive oil. A similar trend of differences (p < 0.05) was found between fatty acid profiles in extra virgin and refined olive oils. As expected, the main differences occurred in monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). Cross-correlation analysis also showed differences between the fatty acid profiles. The most prolific changes were observed between the control samples and the heated (at 180°C) samples of refined olive oil in PUFAs, though a heating temperature of 220°C resulted in similar decrease in MUFAs and PUFAs, in both extra virgin and refined olive oil samples. The study showed differences in fatty acid profiles that can occur during the culinary heating of olive oil. Furthermore, the study indicated that culinary heating of extra virgin olive oil produced results similar to those of the refined olive oil heating at a lower temperature below 180°C.

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Fatty acid positional distribution (sn-2 fatty acids) and phospholipid composition in Chinese breast milk from colostrum to mature stage

British Journal Of Nutrition ◽

10.1017/s0007114518002994 ◽

2018 ◽

Vol 121 (1) ◽

pp. 65-73 ◽

Cited By ~ 9

Author(s):

Ke Wu ◽

Runying Gao ◽

Fang Tian ◽

Yingyi Mao ◽

Bei Wang ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Linoleic Acid ◽

Fatty Acid Profile ◽

Unsaturated Fatty Acids ◽

Fatty Acid Content ◽

Positional Distribution ◽

Phospholipid Composition ◽

Mature Stage ◽

Feeding Time

AbstractThis study quantified the fatty acid profile with emphasis on the stereo-specifically numbered (sn) 2 positional distribution in TAG and the composition of main phospholipids at different lactation stages. Colostrum milk (n 70), transitional milk (n 96) and mature milk (n 82) were obtained longitudinally from healthy lactating women in Shanghai. During lactation, total fatty acid content increased, with SFA dominating in fatty acid profile. A high ratio of n-6:n-3 PUFA was observed as 11:1 over lactation due to the abundance of linoleic acid in Chinese human milk. As the main SFA, palmitic acid showed absolute sn-2 selectivity, while oleic acid, linoleic acid and α-linolenic acid, the main unsaturated fatty acids, were primarily esterified at the sn-1 and sn-3 positions. Nervonic acid and C22 PUFA including DHA were more enriched in colostrum with an sn-2 positional preference. A total of three dominant phospholipids (phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM)) were analysed in the collected samples, and each showed a decline in amount over lactation. PC was the dominant compound followed by SM and PE. With prolonged breast-feeding time, percentage of PE in total phospholipids remained constant, but PC decreased, and SM increased. Results from this study indicated a lipid profile different from Western reports and may aid the development of future infant formula more suitable for Chinese babies.

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Co-valorization of agro-industry by-products: effect of citrus oil on the quality of soap derived from palm fatty acid distillate and spent bleaching clay

Letters in Applied NanoBioScience ◽

10.33263/lianbs83.571575 ◽

2019 ◽

Vol 8 (3) ◽

pp. 571-575

Author(s):

Teerasak Punvichai ◽

Daniel Pioch

Keyword(s):

Fatty Acid ◽

Oil Refining ◽

Bleaching Clay ◽

Microbial Count ◽

Basic Solution ◽

Soap Content ◽

Palm Fatty Acid Distillate ◽

Spent Bleaching Clay ◽

By Products ◽

Fatty Acid Distillate

This study deals with the co-valorization of spent bleaching clay (SBC) and palm fatty acid distillate (PFAD) –by-products of palm oil refining plants- through soap manufacture. Obtained SBC and PFAD samples show differing acidity and saponification values depending on fatty acids and acylglycerols content. Soaps are prepared using the stoichiometric amount of NaOH, under the varying proportion of water introduced through the basic solution. The mixing SBC and PFAD (ratio 1:3), the reaction completion (92.5%) is surprisingly higher than expected, indicating a synergistic effect on the course of the saponification reaction. The water is also a critical parameter, 30% w/w of added water allowing the highest yield. When testing for cleaning efficiency the products having the highest soap content, those from individual by-products give a low microbial count reduction after hand-washing (30-37%). But a much better score (74%) is obtained when using SBC:PFAD soap mixtures. This improvement could be due to abrasive and absorption effects of the clay, combined with the high soap content. The acceptability through a panel test is good for all soaps when formulated with citrus oil. The most active product corresponds to a SBC:PFAD ratio close to the production one in refining plants. Therefore these results provide an easy way for co-valorising these by-products, after further optimizing the saponification reaction in this complex triphasic medium (aqueous solution, oil, clay).

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