Effects of Oils and Fats on the Quality Characteristics, Nutritional Value, and Storage Capacity of Cookies

Introduction. The quality profile and nutritional values of cookies depend on the raw material. The research objective was to study the effect of oils and fats on the quality characteristics and storage capacity of cookies. Study objects and methods. The study involved such types of oils and fats as margarine, confectionery fat, milk fat substitute, palm oil, sunflower oil, and high oleic sunflower oil. It was based on standard methods of sensory, physicochemical, structural, and rheological analyses. Results and discussion. The experimental formulations relied on contemporary dilatory recommendations, consumer acceptability, and traditionality of sensory indicators. The mass fraction of fat was limited to ≤ 18%; added sugars – to ≤ 22%; salt – to ≤ 0.3%. For each type of oil and fat, as set of experiments was performed to define the optimal technological emulsion and dough parameters. Other aspects involved the patterns of moisture transfer, indicators of oxidative spoilage, fatty acid composition, sensory properties, physicochemical and microbiological indicators, storage capacity, etc. The samples with vegetable oils instead of fat had a lower content of saturated fatty acids, which fell from 8–9 to 2–3 g/100 g. However, the risk of oxidative spoilage increased significantly. On storage day 104, the content of linoleic acid in the samples with sunflower oil decreased from 62.0 to 60.4%, while the samples with high oleic sunflower oil maintained the same level of linoleic acid. The samples with confectionery fat and palm oil demonstrated the lowest rate of oxidative processes, while those with margarine and milk fat substitute had the best sensory profile after storage. Conclusion. The cookies with sunflower oil and high oleic sunflower oil appeared to have a shelf life of two months, while for those with milk fat substitute, margarine, palm oil, and confectionery fat it was six months. Further research should focus on various emulsifiers and antioxidants capable of forming bonds with proteins and starch fractions of flour, which could increase the resistance of liquid vegetable oils to oxidation.

Production of human milk fat substitute by engineered strains of Yarrowia lipolytica

Human milk fat has a distinctive stereoisomeric structure where palmitic acid is esterified to the middle (sn-2) position on the glycerol backbone of the triacylglycerol and unsaturated fatty acids to the outer (sn-1/3) positions. This configuration allows for more efficient nutrient absorption in the infant gut. However, the fat used in most infant formulas originates from plants, which tend only to esterify palmitic acid to the sn-1/3 positions. Oleaginous yeasts provide an alternative source of lipids for human nutrition. However, these yeasts also exclude palmitic acid from the sn-2 position of their triacylglycerol. Here we show that Yarrowia lipolytica can be engineered to produce triacylglycerol with more than 60% of the palmitic acid in the sn-2 position, by expression of a lysophosphatidic acid phosphatase with palmitoyl-Coenzyme A specificity, such as LPAAT2 from Chlamydomonas reinhardtii. The engineered Y. lipolytica strains can be cultured on glycerol, glucose, palm oil or a mixture of substrates, under nitrogen limited condition, to produce triacylglycerol with a fatty acid composition that resembles human milk fat, in terms of the major molecular species; palmitic, oleic and linoleic acids. Culture on palm oil or a mixture of glucose and palm oil produced the highest lipid titre in shake flask culture and a triacylglycerol composition that is most similar with human milk fat. Our data show that an oleaginous yeast can be engineered to produce a human milk fat substitute (β-palmitate), that could potentially be used as an ingredient in infant formulas.

Composite Gel Fabricated with Konjac Glucomannan and Carrageenan Could Be Used as a Cube Fat Substitute to Partially Replace Pork Fat in Harbin Dry Sausages

The effect of the partial replacement of pork back-fat with a cube fat substitute (CFS) fabricated from konjac glucomannan and carrageenan on the physicochemical and sensory characteristics of Harbin dry sausages during 7 days of fermentation was investigated. There were the following five treatments: control (100% back-fat), FS1 (80% back-fat, 20% CFS), FS2 (60% back-fat, 40% CFS), FS3 (40% back-fat, 60% CFS) and FS4 (20% back-fat, 80% CFS). The results showed no significant differences (p > 0.05) in the physicochemical and sensory characteristics among the control, FS1 and FS2 treatments. However, higher replacement levels (60% and 80%) rendered higher degrees of change in the characteristics of the sausages, lowering the moisture content and aw and increasing the pH, hardness, chewiness and atypical appearance at the end of fermentation. Moreover, electronic nose analysis and hierarchical cluster analysis demonstrated that the FS3 and FS4 treatments destroyed the characteristic quality of the sausage. Overall, our results indicated that, to ensure the traditional characteristics of Harbin dry sausages, the upper limit of the fat replacement level with CFS should be set at 40%.

FATTY ACID COMPOSITION OF DAIRY PRODUCTS AT THEIR MODIFICATION (FALSIFICATION)

The article presents research on the fat of chicken, goose, lamb, beef, sour cream and a milk-containing product with a milk fat substitute, produced using sour cream technology. There is a tendency towards the absence in the composition of a milk-containing product with a milk fat substitute, butyric, nylon, capric, caprylic, decenoic acids. Fatty acids are also absent in chicken, lamb, beef and goose fats, which makes it possible to exclude the use of these fatty acids in the production of a milk-containing product.