More polyunsaturated fats in processed foods and fewer additives are a huge demand of public health agencies and consumers. Consequently, although foods have an enhanced tendency to oxidize, the usage of antioxidants, especially synthetic antioxidants, is restrained. An alternate solution is to better control the localization of reactants inside the food matrix to limit oxidation. This review establishes the state-of-the-art on lipid oxidation in oil-in-water (O/W) emulsions, with an emphasis on the role of the interfacial region, a critical area in the system in that respect. We first provide a summary on the essential basic knowledge regarding (i) the structure of O/W emulsions and interfaces and (ii) the general mechanisms of lipid oxidation. Then, we discuss the factors involved in the development of lipid oxidation in O/W emulsions with a special focus on the role played by the interfacial region. The multiple effects that can be attributed to emulsifiers according to their chemical structure and their location, and the interrelationships between the parameters that define the physicochemistry and structure of emulsions are highlighted. This work sheds new light on the interpretation of reported results that are sometimes ambiguous or contradictory.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/1541-4337.12097

Lipid Oxidation in Oil‐in‐Water Emulsions: Involvement of the Interfacial Layer

The objective of this study was to chemically and nutritionally characterize the commercial chia seeds and oil from Chile and investigate their antioxidant potential by different in vitro methods. The chia seed presented a good source of protein (25.32 g/100 g), oil (30.22 g/100 g) and total dietary fiber (37.50 g/100 g), with predominant insoluble fiber (35.07 g/100 g). The main fatty acids, ranked order of abundance, were α-linolenic acid > linoleic acid > palmitic acid ∼ oleic acid > stearic acid. The triacylglycerols (TAG) in chia oil were identified by direct mass spectrometry using the easy ambient sonic-spray ionization (EASI-MS) technique and linolenic acid (Ln) was present in the most TAG found. The oil also presented a low peroxide index value (2.56 mEq peroxide/kg). The samples exhibited a high antioxidant activity by the various in vitro methods evaluated; it is due to the presence of phenolic compounds in the seed or oil, which were, mainly, myricetin, quercetin, kaempferol, chlorogenic acid and 3,4-dihydroxyphenylethanol-elenolic acid dialdehyde (3,4-DHPEA-EDA). Our results therefore suggest that Chilean chia seeds and oil should be considered as functional ingredients with high antioxidant potential in food products with commercial applications.

Chemical characterization and antioxidant potential of Chilean chia seeds and oil (Salvia hispanica L.)

Polyunsaturated fatty acids (PUFAs) of the -3 and -6 class (e.g. -linolenic acid, linoleic acid) are essential for maintaining biofunctions in mammalians like humans. Due to the fact that humans cannot synthesize these essential fatty acids, they must be taken up from different food sources. Classical sources for these fatty acids are porcine liver and fish oil. However, microbial lipids or single cell oils, produced by oleaginous microorganisms such as algae, fungi and bacteria, are a promising source as well. These single cell oils can be used for many valuable chemicals with applications not only for nutrition but also for fuels and are therefore an ideal basis for a bio-based economy. A crucial point for the establishment of microbial lipids utilization is the cost-effective production and purification of fuels or products of higher value. The fermentative production can be realized by submerged (SmF) or solid state fermentation (SSF). The yield and the composition of the obtained microbial lipids depend on the type of fermentation and the particular conditions (e.g. medium, pH-value, temperature, aeration, nitrogen source). From an economical point of view, waste or by-product streams can be used as cheap and renewable carbon and nitrogen sources. In general, downstream processing costs are one of the major obstacles to be solved for full economic efficiency of microbial lipids. For the extraction of lipids from microbial biomass cell disruption is most important, because efficiency of cell disruption directly influences subsequent downstream operations and overall extraction efficiencies. A multitude of cell disruption and lipid extraction methods are available, conventional as well as newly emerging methods, which will be described and discussed in terms of large scale applicability, their potential in a modern biorefinery and their influence on product quality. Furthermore, an overview is given about applications of microbial lipids or derived fatty acids with emphasis on food applications.

/pdf/production-strategies-and-applications-of-microbial-single-2rj7kw3zql.pdf

Production Strategies and Applications of Microbial Single Cell Oils

Vitamin D is a micronutrient that is needed for optimal health throughout the whole life. Vitamin D3 (cholecalciferol) can be either synthesized in the human skin upon exposure to the UV light of the sun, or it is obtained from the diet. If the photoconversion in the skin due to reduced sun exposure (e.g., in wintertime) is insufficient, intake of adequate vitamin D from the diet is essential to health. Severe vitamin D deficiency can lead to a multitude of avoidable illnesses; among them are well-known bone diseases like osteoporosis, a number of autoimmune diseases, many different cancers, and some cardiovascular diseases like hypertension are being discussed. Vitamin D is found naturally in only very few foods. Foods containing vitamin D include some fatty fish, fish liver oils, and eggs from hens that have been fed vitamin D and some fortified foods in countries with respective regulations. Based on geographic location or food availability adequate vitamin D intake might not be sufficient on a global scale. The International Osteoporosis Foundation (IOF) has collected the 25-hydroxy-vitamin D plasma levels in populations of different countries using published data and developed a global vitamin D map. This map illustrates the parts of the world, where vitamin D did not reach adequate 25-hydroxyvitamin D plasma levels: 6.7% of the papers report 25-hydroxyvitamin D plasma levels below 25 nmol/L, which indicates vitamin D deficiency, 37.3% are below 50 nmol/Land only 11.9% found 25-hydroxyvitamin D plasma levels above 75 nmol/L target as suggested by vitamin D experts. The vitamin D map is adding further evidence to the vitamin D insufficiency pandemic debate, which is also an issue in the developed world. Besides malnutrition, a condition where the diet does not match to provide the adequate levels of nutrients including micronutrients for growth and maintenance, we obviously have a situation where enough nutrients were consumed, but lacked to reach sufficient vitamin D micronutrient levels. The latter situation is known as hidden hunger. The inadequate vitamin D status impacts on health care costs, which in turn could result in significant savings, if corrected. Since little is known about the effects on the molecular level that accompany the pandemic like epigenetic imprinting, the insufficiency-triggered gene regulations or the genetic background influence on the body to maintain metabolic resilience, future research will be needed. The nutrition community is highly interested in the molecular mechanism that underlies the vitamin D insufficiency caused effect. In recent years, novel large scale technologies have become available that allow the simultaneous acquisition of transcriptome, epigenome, proteome, or metabolome data in cells of organs. These important methods are now used for nutritional approaches summarized in emerging scientific fields of nutrigenomics, nutrigenetics, or nutriepigenetics. It is believed that with the help of these novel concepts further understanding can be generated to develop future sustainable nutrition solutions to safeguard nutrition security.

/pdf/vitamin-d-a-critical-and-essential-micronutrient-for-human-3vapsma9nl.pdf

Vitamin D: a critical and essential micronutrient for human health

Increasing the shelf-life of sensitive substances and targeting the release of nutritional/bioactive molecules are among the great challenges for the food industry. The development of food products with embedded encapsulation devices used to reach these objectives, constitutes a growing market. Milk proteins are biopolymers that are chemically and structurally versatile and are well adapted to several encapsulation purposes. Therefore, in this paper, the strategies, techniques, advantages and trends associated with the use of milk proteins as encapsulating device are reviewed. Special attention is given to the novel potential of reversibly co-assembled protein structures as encapsulating devices.

/pdf/milk-proteins-as-encapsulation-devices-and-delivery-vehicles-1kkox62h78.pdf

Milk proteins as encapsulation devices and delivery vehicles: Applications and trends

A $600 million nutritional supplements market growing at 30% every year attests to consumer awareness of, and interests in, health benefits attributed to these supplements. For over 80 years the importance of polyunsaturated fatty acid (PUFA) consumption for human health has been established. The FDA recently approved the use of ω-3 PUFAs in supplements. Additionally, the market for ω-3 PUFA ingredients grew by 24.3% last year, which affirms their popularity and public awareness of their benefits. PUFAs are essential for normal human growth; however, only minor quantities of the beneficial ω-3 PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are synthesized by human metabolism. Rather PUFAs are obtained via dietary or nutritional supplementation and modified into other beneficial metabolites. A vast literature base is available on the health benefits and biological roles of ω-3 PUFAs and their metabolism; however, information on their dietary sources and palatability of foods incorporated with ω-3 PUFAs is limited. DHA and EPA are added to many foods that are commercially available, such as infant and pet formulae, and they are also supplemented in animal feed to incorporate them in consumer dairy, meat, and poultry products. The chief sources of EPA and DHA are fish oils or purified preparations from microalgae, which when added to foods, impart a fishy flavor that is considered unacceptable. This fishy flavor is completely eliminated by extensively purifying preparations of n-3 PUFA sources. While n-3 PUFA lipid autoxidation is considered the main cause of fishy flavor, the individual oxidation products identified thus far, such as unsaturated carbonyls, do not appear to contribute to fishy flavor or odor. Alternatively, various compound classes such as free fatty acids and volatile sulfur compounds are known to impart fishy flavor to foods. Identification of the causative compounds to reduce and eventually eliminate fishy flavor is important for consumer acceptance of PUFA-fortified foods.

Fortification of Foods with Omega-3 Polyunsaturated Fatty Acids

Manufacture and sensory analysis of reduced- and low-sodium Cheddar and Mozzarella cheeses.

Survival of probiotic adjunct cultures in cheese and challenges in their enumeration using selective media.

Aims

Starter lactic acid bacteria in Cheddar cheese face physico-chemical stresses during manufacture and ageing that alter their abilities to survive and to interact with other bacterial populations Nonstarter bacteria are derived from milk handling, cheese equipment and human contact during manufacture Probiotic bacteria are added to foods for human health benefits that also encounter physiological stresses and microbial competition that may mitigate their survival during ageing We added probiotic Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus paracasei and Bifidobacterium animalis subsp lactis to full-fat, reduced-fat and low-fat Cheddar cheeses, aiming to study their survival over 270 days of ageing and to determine the role of the cheese matrix in their survival



Methods and Results

Probiotic and other lactic acid bacterial populations were enumerated by quantitative PCR using primers specifically targeting the different bacterial genera or species of interest Bifidobacteria were initially added at 106 CFU g−1 cheese and survived variably in the different cheeses over the 270-day ageing process Probiotic lactobacilli that were added at 107 CFU g−1 cheese and incident nonstarter lactobacilli (initially at 108 CFU g−1 cheese) increased by 10- to 100-fold over 270 days Viable bacterial populations were differentiated using propidium monoazide followed by species-specific qPCR assays, which demonstrated that the starter and probiotic microbes survived over ageing, independent of cheese type Addition of probiotic bacteria, at levels 100-fold below that of starter bacteria, modified starter and nonstarter bacterial levels



Conclusions

We demonstrated that starter lactococci, nonstarter lactobacilli and probiotic bacteria are capable of surviving throughout the cheesemaking and ageing process, indicating that delivery via hard cheeses is possible Probiotic addition at lower levels may also alter starter and nonstarter bacterial survival



Significance and Impact of the Study

We applied qPCR to study multispecies survival and viability and distinctly enumerated bacterial species in commercial-scale Cheddar cheese manufacture

https://sfamjournals.onlinelibrary.wiley.com/doi/pdf/10.1111/jam.12482

C. Brothersen

Papers

Fortification of Foods with Omega-3 Polyunsaturated Fatty Acids

Manufacture and sensory analysis of reduced- and low-sodium Cheddar and Mozzarella cheeses.

Survival of probiotic adjunct cultures in cheese and challenges in their enumeration using selective media.

Probiotic bacteria survive in Cheddar cheese and modify populations of other lactic acid bacteria

Fortification of cheese with vitamin D3 using dairy protein emulsions as delivery systems.