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Simple Summary: In this study, we investigated the impact of incorporating freeze-dried mealworm larvae powder (Tenebrio molitor) into wheat bread on its quality, nutritional value, and consumer acceptance. Mealworms represent a sustainable protein source that can enhance the nutritional profile of foods. Bread was prepared with varying concentrations of mealworm powder (5%, 10%, and 15%), which significantly increased the bread's protein and fat content, particularly in terms of essential amino acids and beneficial fatty acids. However, higher levels of mealworm powder also resulted in darker bread and decreased consumer acceptance, as the altered taste and texture were perceived less favourably. This study emphasizes that while mealworm powder can enhance the nutritional value of bread, it is crucial to balance these benefits with sensory qualities to maintain consumer appeal. The findings suggest that mealworm powder could be a valuable ingredient for producing nutritionally enriched bread, provided that consumer preferences are carefully considered. This research contributes to the growing body of literature on the use of insects as sustainable food ingredients. The research context involves analyzing the potential benefits derived from integrating insect protein into everyday food items. Utilizing methods consistent with established food science protocols, wheat bread was prepared with variations of 0%, 5%, 10%, and 15% Tenebrio molitor larvae powder, derived from larvae cultivated on brewery spent grain. A substrate selected for its superior nutritional content and a substrate with agar–agar gels were used. The tests included basic bread tests; sugar, acrylamide, amino, and fatty acid (FA) tests; and sensory acceptability. The results have shown that the acrylamide levels in bread with larvae remained below harmful thresholds, suggesting that using T. molitor can be a safe alternative protein source. The incorporation of powdered T. molitor larvae (p-TMLs) into bread was observed to increase certain sugar levels, such as glucose, particularly at higher larval concentrations. The addition of T. molitor significantly raised the protein and fat levels in bread. The inclusion of larvae enriched the bread with essential amino acids, enhancing the nutritional value of the bread significantly. The FA profile of the bread was altered by the inclusion of p-TMLs, increasing the levels of monounsaturated FAs. Despite the nutritional benefits, higher concentrations of larvae decreased the sensory acceptability of the bread. This suggests that there is a balance to be found between enhancing the nutritional content and maintaining consumer appeal. These findings highlight the potential for using p-TMLs as a sustainable, nutritious ingredient in bread making, although the sensory qualities at higher concentrations might limit consumer acceptance. [ABSTRACT FROM AUTHOR]

Mealworms provide a viable option for transforming agricultural and food processing by-products that can be converted into a valuable source of high-quality protein and fat suitable for both animals and humans. Hence, our investigation was aimed at employing sprouted and green potatoes, wheat bran, and by-products from brewers' production as a comprehensive substrate for rearing mealworms. The nutritional value (fat and protein content) and composition of amino acids (AAs) and fatty acids (FAs) were tested in lyophilized and milled larvae. The results showed that the highest amount of protein was detected in sample 3L (59.18 ± 007%), grown on brewers' spent grain, whereas sample 2S (with wheat bran) comes out with the highest fat content (34.22 ± 0.491%). It was found that the amount of FAs in the larvae depended on the substrate used: the statistically highest amount of monounsaturated FAs was detected in the sample with sprouted potatoes (1L), the highest content of omega-3 FAs was found in the control sample (4CL), with agar–agar gels, and the sample with brewers spent grains (3L) showed a statistically higher amount of oleic acid. Meanwhile, the highest content of total polyunsaturated FAs (36.23%) was detected in the sample with wheat bran (2L). During the study, 16 distinct AAs have been analyzed, and sample 3L has demonstrated the highest content in 11 instances. It is noteworthy that the sample containing brewers' spent grain exhibited the highest peroxide levels, indicating oxidation. Meanwhile, the determined number of volatile fatty acids did not exceed the regulatory limits for meat. In summary, it can be asserted that adjusting the substrate is essential for extracting specific amino acids and FAs. However, this could potentially affect the content of peroxides. This adaptation enables the desired chemical composition in larvae, making it suitable for specific purposes such as animal or human nutrition and health enhancement. [ABSTRACT FROM AUTHOR]

The rising global demand for animal-based food has an increasingly detrimental ecological impact, exacerbated by significant food waste (approximately one-third of all food). This research aimed to analyze the possibility of changing the usually balanced feed with sustainable alternatives that remain as a by-product of the production of farms, grain processing, and breweries, thus promoting the sustainability of agriculture. The mealworm larvae were reared on different substrates: (1) agar-agar gels, wheat bran, and brewer's yeast, (2) carrots, wheat bran, and brewer's yeast, (3) sprouted potatoes, wheat bran, and brewer's yeast, and (4) carrots, brewers' spent grain and brewer's yeast. For analysis, the frozen larvae were lyophilized and tested for chemical safety in three accredited laboratories. The results have shown that all tested samples had lower levels of pesticides than the detection limit. In scientific literature, we didn't find studies on polycyclic aromatic hydrocarbons (PAH). In our study, we found PAH in the substrate and these toxins, as our study shows, can also enter the larvae, but no significant accumulation was observed (sum of benzo(a)pyrene, benz(a)anthracene, benzo(b)fluoranthene and chrysene was 0.0007 mg/kg). Furthermore, the total content of PAH, benzo(a)pyrene and histamine did not exceed recommended levels. We have noticed that the highest concentration of heavy metals (e.g., chromium—1.45 ± 0.02) was found in the sample with the brewer's by-products. While numerous studies utilize plant-derived by-products, the accumulation of glycoalkaloids has not been explored. Among the all glycoalkaloids (tomatidin, tomatine, α-solanine, α-chaconine and solanidin), amounts of α-solanine and α-chaconine were the highest, detected in the sample with sprouted potatoes (175.12 ± 0.21 and 139.32 ± 0.32 mg/kg, respectively). The amount of total putrescine, tyramine, spermine, and spermidine in mealworm larvae was statistically higher compared to the amount detected in the substrate, and histamine level-on the contrary, was statistically significantly lower compared to the amount detected in the substrate. Considering the amount of toxic substances found in the substrate from the by-products, we can assume that mealworms did not accumulate high levels of toxins, which would violate regulations. [ABSTRACT FROM AUTHOR]

Fatty acids (FA) and their composition are very important for human nutrition. Fish products are one of the most beneficial sources of FA for human health; therefore, it is very important to know which products in the Lithuanian market are the most suitable for consumers. The aim of the study was to determine the content of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), the quantity and ratio of omega 6 and omega 3 fatty acids(n-6/n-3) in the raw material of salmon, herring and mackerel and their salted and smoked products, and to calculate the atherogenic (AI) and thrombogenic (TI) indices of these products. The study was carried out in 2019-2020. A test sample for FA analysis was prepared according to LST EN ISO 12966-2:2011 standard. The content of FA was determined by gas chromatography using a flame ionization detector. Chromatographic analysis of fatty acid methyl esters was performed with Shimadzu GC - 2010 (Japan) gas chromatograph, using a BPX - 70, 120 m column according to the LST EN ISO 15304:2003/AC:2005 standard. Compared with heat-treated products, fish raw material (fillets) had a higher content of PUFA (P < 0.05), higher levels of omega 3 FA (n-3) (P < 0.05), and their n-6/n-3 ratio was reliably lower. Salmon products had the healthiest FA composition for humans, the highest amount of omega 3 FA and the most suitable for human diet n-6/n-3 ratio. The most favourable indices of atherogenicity and thrombogenicity (AI - 0.13, TI - 0.1) for human diet in tested fish product samples were calculated in the raw material of Atlantic salmon fillet and were slightly higher than in cold smoked mackerel (AI - 0.23, TI - 0.25). Moreover, the assessment of correlation relationships between individual indicators showed that the ratio n-6/n-3 decreased with increasing quantity of PUFA (coefficient r =-0.602 in salmon; r = -0.628 in mackerel; r = -0.831 in herring products). [ABSTRACT FROM AUTHOR]