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Lipids rich in polyunsaturated fatty acids (PUFA) are of great importance to the food industry. However, due to unsaturation they are highly prone to rancidity, thereby presenting an enormous technological challenge. Emulsification and subsequent microencapsulation of oil forms a protective micro‐environment for these bioactives. Further, freeze drying of emulsified lipids is used to enhance shelf‐life of the dietary targets. In the current study, α‐linolenic acid (ALA) rich oil from Lepidium sativum seed was stabilized through microencapsulation by freeze drying. O/W emulsion was prepared using a combination of gum ghatti, gum arabic, and soy protein isolate. Thereafter induced coacervates were lyophilized by the batch method in a tray dryer. The encapsulation procedure was optimized by the central composite design, through variation of parameters such as the ratio between gum and soy protein isolate (SPI), wall and core and the speed of homogenization. The response was measured in terms of microencapsulation efficiency (MEE) with the maxima of 81.11% for the parameter values of Gum:SPI at 0.32, Wall:Core at 2 and homogenization speed of 10 000 rpm. The prepared emulsion was characterized through ζ‐potential, viscosity, and droplet size measurements while the encapsulated product was deliberated through Raman spectroscopy and aw evaluations. Practical applications: Dietary requirement of polyunsaturated fatty acids (PUFA) is seldom met by a vegetarian diet and therefore for the benefit of the vegetarian population, novel food products incorporating vegetarian PUFA need to be developed. However, rancidity is a major problem encountered while working on unsaturated molecules. Thus to gain maximum benefit from these functional lipids one needs to design stable bioavailable ingredients. With this in mind, the focus of the current study was formulation and process optimization to obtain encapsulated oil. Freeze drying process for microencapsulation leads to superior quality capsules due to the low temperature conditions. In this way L. sativum seed oil was explored for the first time to develop α‐linolenic acid rich bioactive ingredient. Microencapsulation of PUFA rich oil by freeze drying. In the current study α‐linolenic acid rich oil was extracted from Lepidium sativum and processed into a functional ingredient by freeze drying. Soxhlet extracted oil along with SPI, gum arabic, and gum ghatti was utilized for formation of coacervates. Encapsulated oil in the form of coacervates was then dehydrated to form microcapsules in a freeze dryer. The capsules were then analyzed for microencapsulation efficiency and capsule composition. The optimized capsules can be used to deliver α‐linolenic acid rich oil in novel targeted food products.

Mussel cultivation results in tons of by-product, with 27% of the harvest considered as reject material. In this study, mussel by-products considered to be undersized (mussels with a cooked meat yield <30%), mussels with broken shells and barnacle-fouled mussels were collected from three different locations in the west, north-west and south-west of Ireland. Samples were hydrolysed using controlled temperatures and agitation, and the proteolytic enzyme Protamex® was added at an enzyme:substrate ratio of 1:50 (w:v). The hydrolysates were freeze-dried and analysed for protein content and amino acid composition, lipid content and fatty acid methyl ester (FAME) composition, ash and techno-functional and bioactive activities. The degree of hydrolysis was determined using the Adler-Nissen pH stat method and was found to be between 2.41% ± 0% and 7.55 ± 0.6 %. Mussel by-products harvested between February and May 2019 had protein contents ranging from 36.76% ± 0.41% to 52.19% ± 1.78%. The protein content of mussels collected from July to October (the spawning season) ranged from 59.07% ± 1.375% to 68.31% ± 3.42%. The ratio of essential to nonessential amino acids varied from 0.68–0.96 and it was highest for a sample collected in November from the west of Ireland. All the hydrolysate samples contained omega-3 polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are known anti-inflammatory agents. Selected hydrolysates which had angiotensin-converting enzyme I (ACE-I; EC 3.4.15.1) and dipeptidyl peptidase IV (DPP-IV; EC 3.4.14.5) inhibitory activities were filtered using 3-kDa membrane filtration and the permeate fraction was sequenced using mass spectrometry (MS). Identified peptides were >7 amino acids in length. Following BIOPEP database mining, 91% of the by-product mussel peptides identified were found to be previously identified DPP-IV and ACE-I inhibitory peptides, and this was confirmed using in vitro bioassays. The ACE-I inhibitory activity of the by-product mussel hydrolysates ranged from 22.23% ± 1.79% to 86.08% ± 1.59% and the most active hydrolysate had an ACE-I inhibitory concentration (IC50) value of 0.2944 mg/mL compared to the positive control, captopril. This work demonstrates that by-product mussel hydrolysates have potential for use as health-promoting ingredients.

Brewers' spent grain (BSG), a brewery by‐product, seldom finds high value applications. The present work investigated functionality of BSG oil fractions through evaluation of its 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) quenching ability. The scavenging activity of BSG oil was 71.60% and was more than its polar, nonpolar and unsaponified fractions (61.14, 52.42, and 34.47%). The IC50 of the BSG oil (7.39 µg mL−1) was 1000 times lower than common antioxidants—Ascorbic acid (2.86 mg mL−1) and BHT (2.60 mg mL−1), establishing its superior antioxidant activity. The total phenolic content of oil was found to be 1.22 mg GAE per ml of oil while its protein content was found to be between 10.2 and 11.0 mg mL−1. EPR spectroscopy showed 100% quenching of DPPH at 0.5% (w/v) of oil. GCMS revealed the presence of anti‐oxidants. The accelerated oxidation study showed acceptable values for peroxide (till 6 hr) and anisidine (1 hr) tests. Practical applications Brewer' spent grain (BSG) comprises residual constituents of the brewing process that have been utilized for low value applications. The present study revealed a number of bioactive compounds (antioxidants and phenolic compounds) and volatiles in the BSG oil. The antioxidant functionality of this phytochemical rich extract can be utilized for nutraceutical applications to reduce free radical damage in humans. For food preservation, the oil can be employed to reduce browning, rancidity and other deterioration reactions. Thus oil extracted from waste by‐product can be used for high value applications.