Dietary inclusion of defatted silkworm (Bombyx mori L.) pupa meal in broiler chickens: phase feeding effects on nutritional and sensory meat quality

The present experiment was conducted to test the effect of a 4% defatted silkworm (Bombyx mori) pupae meal (SWM) incorporation into chickens' diets at different growth phases on meat quality characteristics and sensory traits. Ninety ROSS 308 day-old male broiler chickens were randomly assigned to 3 dietary groups, with 5 replicated pens/diet: the first group received a control (C) diet throughout the growing period of 42 d, the second group received a diet with 4% SWM (SWM1) during the starter phase (1-10 d) and the C diet up to slaughter, whereas the third group was fed the C diet during the starter phase and 4% SWM during the grower and finisher phases (SWM2). Diets were isonitrogenous and isoenergy, and birds had free access to feed and water throughout the experimental trial. At 42 d of age, 15 chickens/treatment were slaughtered at a commercial abattoir. Fatty acid (FA) and amino acid (AA) profiles and contents of meat, as well as its oxidative status, were determined in both breast and leg meat cuts. Also, a descriptive sensory analysis was performed on breast meat by trained panelists. Results highlighted that the SWM2 treatment increased the n-3 proportion and content in both breast and leg meat, thereby improving the omega-6/omega-3 (n-6/n-3) ratio in both cuts (P < 0.001). However, the dietary treatment had no significant effect on the oxidative status of either breast or leg meat (P > 0.05). The SWM had a limited impact on overall sensory traits of breast meat, but it contributed to improve meat tenderness in SWM-fed chickens (P < 0.01). Furthermore, SWM1 meat exhibited higher juiciness (P < 0.05) and off flavor intensity (P < 0.05) compared to the control meat. Overall, the present experiment indicated that defatted SWM holds promise as an alternative ingredient in chicken rations, ensuring satisfactory meat quality. Furthermore, administering SWM during the grower-finisher phase demonstrated beneficial effects on meat healthiness, ultimately enhancing n-3 fatty acids content and reducing the n-6/n-3 ratio.

Live yellow mealworm (Tenebrio molitor) larvae: a promising nutritional enrichment for laying quails

The study aimed to evaluate the effect of supplementing live Tenebrio molitor (TM) larvae to laying quails (Coturnix japonica) as nutritional enrichment. Live performances, apparent digestibility of nutrients (including that of sole live TM larvae), egg physicochemical quality, sensory traits, and storage stability were considered in this experiment. Sixty laying quails were divided into 2 dietary groups (6 replicated cages/group; 5 quails/cage): a Control group received a basal diet for laying quails and a TM10 group was fed with the Control diet supplemented with live TM larvae (10% of the expected daily feed intake). For the digestibility trial, 30 laying quails were divided into 3 dietary groups: the first 2 groups were fed with the Control and TM10 diets, while the third group received ad libitum live TM larvae (TM100) as a complete replacement for the Control diet. Overall, no mortality was recorded during the trials. Quails fed TM showed a remarkable capability of digesting dietary chitin (P < 0.0001). TM100 quails showed the lowest digestibility for dry matter, crude protein, and energy, but that of ether extract was the highest (P < 0.001). The presence of live TM larvae stimulated quails' feed intake (P < 0.0001), but did not affect performance traits. Similarly, overall physicochemical quality attributes and storage stability were comparable in Control and TM10 eggs. The sensory features of quail eggs differed in TM10 vs. Control groups: TM10 eggs had the lowest overall flavor (P < 0.01), sulfur (P < 0.05) and greasy-oily (P < 0.01) intensities. Therefore, a 10% TM dietary supplementation is effective in stimulating feeding activity of quails, but it did not provide any productive improvement compared to a standard diet. Further studies should assess the possible beneficial effect of live TM supplementation on quail's gut health. The digestibility trial with the sole live TM larvae allowed to assess the specific nutritional value of this emerging feedstuff which is of utmost importance for future feed formulations.

Determining the hierarchical order by which intestinal tract, administered diet, and individual relay can shape the gut microbiome of fattening quails

A bacterial metabarcoding approach was used to compare the microbiome composition of caecal and faecal samples from fattening Japanese quails (Coturnix coturnix japonica) fed three different diet regimes. The tested feedstuffs included (1) a commercial diet for fattening quails, (2) a commercial diet containing 12% full-fat silkworm (Bombyx mori) pupae meal, and (3) a commercial diet containing 12% defatted silkworm pupae meal. The aim of the experiment was to verify the relative effect of three variables (diet type, gut tract comparing caecum to rectum, and individual animal) in determining the level of bacterial community dissimilarity to rank the relevance of each of the three factors in affecting and shaping community composition. To infer such ranking, the communities resulting from the high-throughput sequencing from each sample were used to calculate the Bray-Curtis distances in all the pairwise combinations, whereby identical communities would score 0 and totally different ones would yield the maximum distance, equal to 1. The results indicated that the main driver of divergence was the gut tract, as distances between caecal and faecal samples were higher on average, irrespective of diet composition, which scored second in rank, and of whether they had been sampled from the same individual, which was the least effective factor. Simpson's species diversity indexes was not significantly different when comparing tracts or diets, while community evenness was reduced in full-fat silkworm diet-fed animals. The identities of the differentially displayed taxa that were statistically significant as a function of gut tract and diet regimen are discussed in light of their known physiological and functional traits.

Eurasian consumers' food safety beliefs and trust issues in the age of COVID-19: evidence from an online survey in 15 countries

BACKGROUND

This investigation provides an important insight into Eurasian consumers' food safety beliefs and trust issues influenced by the COVID-19 pandemic. An online survey was conducted in 15 European and Asian countries involving more than 4000 consumers.

RESULTS

It has confirmed that different socioeconomic characteristics, cultural aspects and education levels shape food safety perceptions within Eurasian countries. The COVID-19 pandemic influenced their beliefs and trust in food safety, which is relatively low on average. However, it is significantly higher for European consumers (especially European Union ones) compared to their Asian counterparts. Both Asian and European respondents agreed that food fraud and climate changes represent a food safety issue. However, European consumers were less concerned regarding the food safety of genetically modified foods and meat and dairy analogs/hybrids. Asian consumers were, to a greater extent, worried about the risk of getting COVID-19 from food, restaurants, food retail establishments and home food deliveries.

CONCLUSION

Eurasian consumers have put their greatest extent of trust, when food safety assurance is concerned, into food scientists and food producers holding a food safety certificate. Broadly, they are uncertain to what extent their federal governments and food inspectors are competent, able and efficient in ensuring food safety. Higher education of Eurasian consumers was followed by increased food safety confidence in all parts of the food chain. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Potential of Full-Fat Silkworm-Based Diets for Laying Quails: Performance and Egg Physical Quality

The present research was conducted to determine the optimal inclusion level of full-fat silkworm chrysalis meal (SWM) into laying quails' diets, focusing on performance traits and egg physical quality. A total of 240 31-day-old female Japanese quails were randomly assigned to four dietary groups (12 replicates/treatment; 5 quails/replicate); quails were initially fed a standard commercial diet for pullets until 63 days of age. When oviposition started, the experimental groups received the following diets: a conventional corn and soybean-based diet (control diet-C) and three other diets, including 4%, 8%, or 12% of full-fat SWM (SWM4, SWM8, SWM12, respectively). Experimental diets were provided until quails reached 119 days of age. Birds displayed satisfactory productive performance throughout the trial. SWM12 and SWM8 had higher (p < 0.001) egg production but also a higher feed conversion ratio compared to C. At the end of the trial, the eggs edible portion increased, and shell weight decreased with increasing the SWM dietary inclusion level (p < 0.001). At the same time, SWM12 displayed an increase in albumen pH (p < 0.05), even though in the normal range for quail egg. Overall, full-fat SWM (up to 12%) can be considered a promising feed ingredient for laying quails, although higher inclusion levels (>8%) require special attention because SWM also contains anti-nutritional factors.

Effect of the dietary inclusion of Camelina sativa cake into quail diet on live performance, carcass traits and meat quality

The present research studied the effect of the dietary inclusion of 3 different camelina (Camelina sativa (L.) Crantz) cakes on the live performance, slaughter traits, and breast meat quality of broiler quails (Coturnix japonica). With this purpose, a total of 480 fifteen-day-old broiler quails of both sexes were allocated to 48 cages (12 replicates/treatment, 10 quails/replicate) and received 4 dietary treatments: a control diet (Control), and 3 diets containing 15% of 1 commercial cultivar (Calena), and 2 improved lines (Pearl: low linoleic acid; Alan: low glucosinolates). During the experiment, individual live weight (LW) and cage feed intake were recorded to calculate body weight gain (BWG) and feed conversion ratio (FCR). At 35 d of age, quails were slaughtered, and carcasses were weighed and dissected to compute yields. On breast (pectoralis major muscle) the measurements and analyses considered ultimate pH, L*a*b* color values, proximate composition, oxidative status, cooking loss and WBSF toughness. Broiler quails receiving diets with camelina cakes exhibited mortality and health status similar to the control. However, growth performance was impaired in camelina-fed groups, especially for Calena (P < 0.05). Overall LW and BWG were slightly lower, whereas feed intake was slightly higher in camelina-fed groups compared to Control (P > 0.05). Therefore, higher FCR was recorded for camelina-fed groups compared to Control (P = 0.0004). Moreover, breast meat from Calena treatment displayed higher water (P = 0.0170), and lower lipid (P = 0.0051) contents compared to those of the Control group, while protein and ash content remained unaffected. Heme-iron content and oxidative status of breast meat were not influenced by the dietary incorporation of camelina (P > 0.05). The research outcomes indicated that camelina cakes can be used as an alternative feed ingredient for broiler quails' diets, without compromising carcass yields and meat quality. However, as 15% dietary incorporation worsened live performance, the ideal camelina cake inclusion level should be thoroughly investigated as well as a parallel research effort into further reducing glucosinolates content of camelina.

Sample preparation and storage effects on fatty acid profile of rabbit Longissimus thoracis et lumborum muscle

Twenty-five Pannon White male rabbits reared and fed in similar conditions were slaughtered at 11 weeks of age. The longissimus thoracis et lumborum muscles (LTL; right and left) were removed at 24 h post-mortem and allocated to four sampling/storage treatments: the left side of LTL muscle was divided in half perpendicularly, with the posterior portion being analysed within one day (fresh), and the anterior portion vacuum packaged and stored for 1 mo at –20°C (whole-frozen); the right LTL side was ground with half of the product vacuum packaged and frozen for 1 mo at –20°C (ground-frozen), whereas the other half was freeze-dried, vacuum packaged, and stored for 1 mo at 4°C (freeze-dried refrigerated). Treatments impacted percentages of total saturated (P<0.01), monounsaturated (P<0.05), and polyunsaturated fatty acids (P<0.001), whole-frozen treatment affecting the most the fatty acids profile of the meat. Method of preparation and storage of meat samples before performing fatty acid analysis had an impact on the percentage of specific fatty acids, which could render the precision of study-to-study comparisons less reliable.

Nutritional Composition of Bombyx mori Pupae: A Systematic Review

Simple Summary

The mulberry silkworm (Bombyx mori) is a domesticated insect traditionally reared to produce silk. Its pupae are historically eaten in Asian countries and are obtained as waste products from the silk reeling industry. Pupae are a promising novel food in Western countries as well as a source of proteins, lipids, and minerals. Several varied results are reported in the literature regarding the nutrient composition of silkworm pupa, and several factors must be considered when comparing the research. Some of the variables that could affect the pupal nutritional content include rearing techniques, diets, silkworm strains, killing, and drying techniques. This literature systematic review identifies the most important research areas and aids authorities and producers in the evaluation and development of silkworm pupae for novel uses.

Abstract

As insects have started to enter the eating habits of Western countries, an increasing amount of literature regarding the mulberry silkworm (Bombyx mori) prospective application as food has been published. Despite this growing interest, there is currently no systematic review of silkworm nutritional composition available. In this paper, we performed a systematic review of the recent available literature on the nutrient composition of mulberry silkworm pupae. After screening the titles and abstracts of 14,008 studies retrieved from three scientific databases, data about nutrients was extracted from 29 selected papers, together with their related variables. This systematic review provides an overview of the variety of data reported in the literature and highlights that many elements contribute to hindering a sound comparison of the different nutritional values reported for silkworm pupae. The observed variability of the composition data reported could be due to differences in diet, strains, pretreatments, and origin of the silkworm analyzed. However, all these variables were not always available and should be reported in future studies to simplify the data comparison.

Myofibrillar protein characteristics of fast or slow frozen pork during subsequent storage at -3 °C

This study aimed to investigate the effect of storage at -3 °C on myofibrillar protein in fast or slow frozen pork. Five pork loins at 48 h post-mortem were subjected to either fast (cold metal plate/-80 °C) or slow freezing (still air/-20 °C) followed by storage at -3 °C for 0, 1, 3, and 7 days before thawing. Freezing rate significantly influenced myofibrillar proteins within 3 days at -3 °C, evidenced by higher thaw loss, higher surface hydrophobicity and reduced water-holding of myofibrils, and accelerated appearance of a myosin-4 fragment (160 kDa) in slow freezing. However, these observed differences disappeared after 7 days of storage at -3 °C. The meat pH after thawing did not differ between fast and slow freezing rate. However, the pH values after thawing in both groups decreased with extended storage at -3 °C. Our results suggest that the beneficial effects of fast freezing are gradually lost by holding at -3 °C due to more extensive protein denaturation.

Effect of ambient temperature on the productive and carcass traits of growing rabbits divergently selected for body fat content

Rabbits are particularly sensitive to heat stress which can affect productive performance, with rabbit breed/line possibly playing a role on the response to this condition. The study aimed at evaluating the effect of different ambient temperatures on the live performance and carcass traits of growing rabbits divergently selected for total body fat content. The two genetic lines (Lean and Fat) were selected based on the total body fat content estimated by computer tomography during five generations. From birth to slaughter (13 weeks of age), the rabbits were housed in two rooms where the temperature was controlled with air conditioners: in the control room the average ambient temperature was 20 °C and in the high temperature room it was 28 °C. After weaning (35 d), 60 Lean and 60 Fat rabbits/room were housed by two in wire-mesh cages and fed ad libitum with commercial pellets. The BW and feed intake (FI) were measured at 5, 7, 9, 11 and 13 weeks of age to calculate the daily weight gain (DWG) and feed conversion ratio (FCR). Mortality was recorded daily. At the end of the experiment, rabbits were slaughtered and carcass traits were measured. Mortality was independent of temperature and line. The temperature significantly influenced the FI, DWG, BW and the fat deposits: they were lower at higher ambient temperature. The effect of temperature differed according to the rabbits' total body fat content. At control temperature, the FI (165 vs 155 g/day; P < 0.05) and FCR (4.67 vs 4.31; P < 0.05) were higher in Fat rabbits, which also had more perirenal (36.2 vs 23.1 g; P < 0.05) and scapular fat (10.8 vs 7.1 g; P < 0.05). At high temperature, no differences in fat depots (14.5 vs 9.8 g; 5.3 vs 3.5 g) were found between the two lines. It can be concluded that temperature × genetic line interaction had an important role in productive and carcass traits, as the effect of temperature differs between Lean and Fat rabbits.

Covid-19 pandemic effects on food safety - Multi-country survey study

This study provides an important insight into the response of food safety systems during the first months of the pandemic, elevating the perspective of preventing Covid-19 within conventional food safety management systems. A multi-country survey was conducted in 16 countries involving 825 food companies. Based on the results of the survey, it is obvious that the level of maturity of a food safety system in place is the main trigger in classifying companies and their responses to the pandemic challenge. Staff awareness and hygiene are the two most important attributes in combating Covid-19, opposed to temperature checking of workers in food establishment and health protocols from the World Health Organization, recognized as attributes with limited salience and importance. Companies confirmed implementation of more restrictive hygiene procedures during the pandemic and the need for purchasing more additional personal protective equipment. Retailers were identified as the food supply chain link mostly affected by the pandemic opposed to food storage facilities ranked as least affected. During this challenging period, all companies declared that food safety has not been compromised at any moment. It is important to note that less than a half of the food companies had documented any emergency plans associated with pandemics and health issues in place.

Rabbit Lines Divergently Selected for Total Body Fat Content: Correlated Responses on Growth Performance and Carcass Traits

The aim of this experiment was to study the effect of divergently selected rabbits for total body fat content (fat index) on growth performance and carcass traits. The fat index was determined at 10 weeks of age by computed tomography and lasted for four consecutive generations. The rabbits with the lowest fat index belonged to the lean line and those of the highest values belonged to the fat line. At generation four, 60 rabbits/line were housed in wire-mesh cages and fed with commercial pellet ad libitum from weaning (5 w of age) to slaughtering (11 w of age). Growth performance, dressing out percentage and carcass adiposity were measured. The lean line showed a better feed conversion ratio (p < 0.001) than the fat line. Furthermore, the carcass of the lean rabbits had the highest proportion of fore (p < 0.020) and hind (p < 0.006) parts. On the contrary, rabbits of the fat line had the highest carcass adiposity (p < 0.001). The divergent selection for total body fat content showed to be effective for both lean and fat lines. Selection for lower total body fat content could be useful for terminal male lines, while the selection for higher total body fat content could be an advantage for rabbit does in providing fat (energy) reserves.

Are Meat Quality Traits and Sensory Attributes in Favor of Slow-Growing Chickens?

The present study compared certain quality features and sensory attributes of the meat obtained from three different chicken genotypes: two endangered slow-growing indigenous breeds (Padovana: PAD, Polverara: POL) and a commercial broiler (Hybrid). Chickens (n = 42/genotype) were slaughtered at their commercial slaughter age: 183 days for PAD and POL chickens, and 35 days for the Hybrid. Breast and leg meat were dissected and used for qualitative evaluations. Results highlighted that genotype significantly affected final breast weight, with Hybrid showing higher values than both indigenous chickens. Conversely, PAD and POL meat was instrumentally tougher and richer in haem iron compared to the Hybrid. The sensory analysis conducted by a trained panel showed that the textural aspects and metallic flavor perception of PAD and POL meat differed from that of the Hybrid. These aspects were probably responsible for the lower overall acceptability of the PAD and POL meat compared to the Hybrid, as expressed by the consumer panel. A key step in making PAD and POL meat acceptable to consumers and stimulating its market seems thus the development of appropriate marketing strategies to transform product peculiarities in strength points.

Proximate Composition, Amino Acid Profile, and Oxidative Stability of Slow-Growing Indigenous Chickens Compared with Commercial Broiler Chickens

The increased demand for chicken meat products has led to chickens with increased growth rates and heavier slaughter weights. This has had unintentional negative effects on the genetics of these animals, such as spontaneous, idiopathic muscle abnormalities. There has also been a shift in customer preference towards products from alternative farming systems such as organic and free-range. Indigenous purebred chickens, such as the Polverara, show potential in these systems as they are adapted to more extensive systems. The aim of the present study was to characterize the meat quality traits of the Polverara, by comparing the proximate composition and amino acid profile with that of a commercial Hybrid. In addition, the lipid and protein oxidation was analyzed after eight days of storage. A total of 120 leg meat samples, 60 Polverara and 60 Hybrid were analyzed. Polverara exhibited higher protein content, lower lipid content, and a better amino acid profile. These results indicate that the Polverara has better nutritional meat quality. However, Polverara also showed higher levels of lipid and protein oxidation. Therefore, further research is needed, especially in regards to the fatty acid profile and mineral content of the meat, which is known to affect oxidative stability.

Effects of honeybush (Cyclopia subternata) extract on physico-chemical, oxidative and sensory traits of typical Italian salami

Honeybush (Cyclopia subternata Vogel) is an indigenous South African shrub enjoyed as hot brewed tea. "Unfermented" honeybush is also a potential antioxidant bioactive extract for foodstuffs due to its polyphenol content. The effect of "unfermented" honeybush extract (Hob; 0.5%) was evaluated in typical Italian salami and compared with nitrate (Nit; 100 mg/kg) and a control (Ctl; without nitrate or honeybush). After 35 days of ripening, Hob had a higher (p < .01) water activity (0.928), compared with Ctl (0.923) and Nit (0.924). Final pH (5.35-5.24) was not affected by treatments. Lower lipid oxidation was observed in Hob and Nit treatments (p < .001) compared with Ctl. Internal color and odor intensity were similar among treatments. Salami with honeybush extract had less spontaneous outer surface mold growth whereas the Ctl showed intermediate growth (p < .05). Honeybush extract seems a promising natural ingredient with antioxidant action.

Fat Inclusion Level, NaCl Content and LAB Starter Cultures in the Manufacturing of Italian-Type Ostrich Salami: Weight Loss and Nutritional Traits

The experiment studied the effect of two different fat inclusion levels (30% and 40%), NaCl contents (2.4 and 2.6%) and starter cultures (lactic acid bacteria (LAB) 6: L. curvatus/S. xylosus; LAB 8: L. sakei/S. xylosus) on the weight loss and nutritional composition of Italian-type ostrich salami. With this purpose, 8 batches of 9 salami each (n = 72) were prepared. Salami were ripened for 20 weeks: weight loss was monitored throughout the experiment, while salami nutritional composition was evaluated at 10 and 20 weeks of ripening. The lowest fat and highest salt inclusion levels provided the highest cumulative weight loss throughout the trial. At 10 weeks of ripening, salami with 40% fat were the richest in moisture and fat, whereas the leanest ones had the highest protein, ash and cholesterol contents. LAB 6 provided salami with the highest moisture and protein, while LAB 8 increased fat and cholesterol contents. At 20 weeks of ripening the proximate composition of ostrich salami was solely affected by fat inclusion level, with similar findings to those observed at 10 weeks. Overall, fat inclusion level had a great impact on the weight loss and nutritional composition of Italian-style ostrich salami. Reducing the NaCl inclusion from 2.6% to 2.4%, the weight loss of ostrich salami was retarded by approximately 1 week, without affecting the nutritional composition of the final product. Results of the study suggested that it is feasible to produce salami with lower fat and salt contents, while ensuring satisfactory product quality.

Research Note: Effect of chicken genotype and white striping-wooden breast condition on breast meat proximate composition and amino acid profile

The present experiment compared the proximate composition, the amino acid content, and profile of the breast meat of a commercial broiler hybrid (Hybrid-Normal) vs. a broiler hybrid affected by the simultaneous presence of white striping (WS) and wooden breast (WB) myopathies (Hybrid-WSWB) vs. the Italian purebred Polverara chicken (Polverara). To this purpose, a total of n = 30 breast meat cuts from male chickens/group were subjected to meat quality evaluations. Chickens were slaughtered at their commercial age. The meat of the Polverara breed showed the highest protein (P < 0.0001) and the lowest lipids (P < 0.0001) contents, whereas that of the Hybrid-WSWB broiler chickens had the lowest protein and ash (P < 0.0001) contents and the highest (P < 0.0001) amount of fat. Meat of Hybrid-Normal chickens displayed intermediate values. Polverara meat was the richest in most amino acids (g/100 g meat), whereas Hybrid-WSWB one had the lowest content (P < 0.0001). Taurine was not detected in the meat of the Polverara chicken. The meat of Hybrid-Normal chickens was the richest in valine and taurine amino acids (P < 0.0001). Results on the amino acids proportions (% of total amino acids) highlighted that lysine, arginine, leucine, glutamic acid, aspartic acid, alanine, and serine were the most representative essential and nonessential amino acids, respectively, in all 3 meat-types chickens. The study confirmed that WS and WB myopathies negatively affect the meat proximate composition and the amino acid content. The meat of the Polverara breed displayed a remarkable meat quality including a high protein content of very good quality. This may represent a tool to promote its meat among consumers and help the survival of this endangered breed. Furthermore, research efforts should be conducted to understand why taurine was absent in the breast meat of Polverara chicken.

The antioxidant effectiveness of liquorice (Glycyrrhiza glabra L.) extract administered as dietary supplementation and/or as a burger additive in rabbit meat

The present research studied the effect of liquorice extract (in feed and/or directly in burgers) on the shelf-life of rabbit meat. Before weaning, 28 individually caged rabbit does with their litters were divided in two dietary groups: Control, receiving a commercial diet, and Liquorice, receiving the Control diet supplemented with 6 g liquorice extract/kg (L). At 12 weeks of age, 15 fattened rabbits/treatment (one rabbit/cage) were slaughtered and their hindlegs dissected. Hindleg meat was trimmed, individually minced and divided into two parts: one of them was mixed with 0.25% (w/w) L. Storage time significantly reduced the amount of polyunsaturated fatty acids in the burger, to a different magnitude depending on the unsaturation level, experimental group and storage time. The α-tocopherol content showed higher levels during storage in the burgers from the Liquorice group. Also TBARs values showed a significant positive effect of dietary liquorice and a progressive increase at days 3 and 6 of storage.

Hermetia illucens Larvae Reared on Different Substrates in Broiler Quail Diets: Effect on Physicochemical and Sensory Quality of the Quail Meat

This research aimed at improving the fatty acid (FA) profile of Hermetia illucens larvae (HI) and evaluating the effects of their inclusion in growing broiler quails' diets on the meat physicochemical quality, including detailed amino acid (AA) and FA profiles, sensory traits, and retail display. HI larvae were reared on two different substrates: layer mash (HI1) and 50:50 layer mash/fish offal (HI2). A total of 300 10-day-old quails were allocated to the three dietary groups (five replicates/each): a soybean meal-based diet was formulated (Control), and two other diets were formulated that included either 10% HI1 or HI2. Quails were fed the experimental diets until slaughter. Diets were formulated to be isonitrogenous and isoenergetic. Breast meat quality was affected by the dietary treatments, which displayed different proximate compositions and AA and FA profiles. Meat physical quality, sensory profile, and retail display remained unaffected for the most part. Overall, results showed that it is possible to improve the FA profile of the HI-fed quails' meat and thus lipid quality through substrate modulation of the HI's diet.

The effects of dietary quercetin supplementation on the meat quality and volatile profile of rabbit meat during chilled storage

Thirty-four New Zealand White rabbits of both sexes were fed a control or supplemented (2 g/kg quercetin dihydrate) diet from weaning until slaughter (13 weeks). After post-mortem chilling, excised and minced Longissimus thoracis et lumborum muscles were stored at 3.2 °C under oxygen-permeable wrapping for 1, 3 or 5 days. Colour, pH, lipid oxidation (TBARS), antioxidant capacity (FRAP), volatile profile (day 1 and 5) and microbial count (day 5) were determined. Quercetin reduced alkane (day 5) and hexanal (day 1) concentrations, but otherwise had minimal antioxidant effect, and did not benefit microbial quality, and thus did not substantially improve the shelf-life. The sex effect was similarly limited. Overall, the pH increased and FRAP decreased during storage, but TBARS did not change and discolouration seemed delayed. The volatile profile was dominated by esters, alcohols and heterocyclic compounds, and while it changed during storage, lipid oxidation products did not increase as expected, suggesting that rabbit meat may have relatively active reducing mechanisms.

Meat Quality and Sensory Traits of Finisher Broiler Chickens Fed with Black Soldier Fly (Hermetia Illucens L.) Larvae Fat as Alternative Fat Source

At present, there is limited knowledge about the possible utilization of the fat fraction derived from Hermetia illucens (HI) larvae processing. The objective of the present study was to evaluate the replacement of soybean oil with HI larvae fat in broiler finisher diet, on the quality and sensory traits of their meat. At 21 days of age, 120 male broiler chickens were randomly allocated to three experimental groups (5 replicates and 8 birds/pen): a basal control diet (C), and two groups in which either 50% or 100% of the soybean oil was replaced with HI larvae fat (the HI50 and HI100 group, respectively). At day 48, 15 birds (3 birds/pen) per group were slaughtered, and breasts and legs were excised and used for meat quality evaluations. Breast and leg physical meat quality, nutritional composition and sensory profile remained substantially unaffected by the dietary treatments. In contrast, the dietary incorporation of HI larvae fat modified the fatty acid (FA) profile of both the breast and leg meat cuts: the proportion of saturated fatty acids increased (p < 0.0001) to the detriment of the polyunsaturated (PUFA) fraction (p < 0.0001). Moreover, the meat n-6/n-3 ratio increased in the HI50 and HI100 groups compared to the C group. HI larvae fat dietary inclusion decreased the monounsaturated fatty acids in the breast (p = 0.0012) but not in the leg meat. Further research should focus on the improvement of the FA profile of the larvae through substrate modulation, or by combining HI larvae with a PUFA-rich feedstuff in feed formulations.

Black Soldier Fly (Hermetia Illucens) as Dietary Source for Laying Quails: Live Performance, and Egg Physico-Chemical Quality, Sensory Profile and Storage Stability

Insects are promising candidates as alternative sustainable sources of protein for poultry species. The present research studied the effect of a dietary inclusion of a defatted black soldier fly (BSF) larvae meal as an alternative protein source in the diets of laying quails, on productive performance, egg physicochemical quality, fatty acid profile, sensory traits and storage stability. A total of 225 laying quails were divided into 3 dietary groups (5 replicates/each). A conventional soybean meal-based diet was formulated (Control group), and two other diets were formulated including either 10% (BSF10) or 15% (BSF15) defatted BSF larvae meal. Laying quails showed satisfactory productive performance throughout the trial. BSF10 and BSF15 eggs had the highest shape index (p < 0.01), shell weight and percentage (p < 0.001) and the most intense yolk color (p < 0.001). Defatted BSF larvae meal increased the eggs' saturated fatty acid content (p < 0.001) to the detriment of the polyunsaturated fraction (p < 0.001). Overall the eggs' sensory profile was not affected by the dietary treatment, but BSF15 eggs had a higher feed off-flavor vs Control group (p < 0.05). At day 28 of storage, oxidative stability was higher in BSF10 vs. Control eggs (p < 0.01). Defatted BSF larvae meal can be considered a possible alternative ingredient to soybean meal in laying quail diets, up to the 15% inclusion level.

Effects of three different stunning/slaughtering methods on physical, chemical, and sensory changes in rainbow trout (Oncorhynchus mykiss)

BACKGROUND

Electrical stunning (E) and asphyxia in the air (A) are two common stunning/killing methods for fish. However, they can stress the fish and affect flesh quality, so an alternative should be found. The present study aimed to evaluate the effects of carbon monoxide asphyxia (CO) compared to E and A on the evolution of post rigor mortis changes in rainbow trout (Oncorhynchus mykiss) fillets related to chemical, textural, and sensorial properties during storage time.

RESULTS

Fish fillets from the E group showed a higher pH (P < 0.05) than the A ones, both at time of rigor resolution (T_RR 0) and from T_RR 4 until T_RR 7 (7 days after rigor resolution, which corresponded to 10 days post mortem), with the CO group being always intermediate. The CO treatment ensured that the fillets showed the lowest yellowness index (b*), even if only at T_RR 2 and T_RR 5. Lipid oxidation and texture profile analyses were unaffected. Sensory analysis revealed that the CO fillets had the lowest odor intensity and the highest juiciness scores (P < 0.05). The sensory descriptors resulted the most discriminant variables of the fillets obtained from the differently stunned animals, as resulted by the canonical discriminant analysis.

CONCLUSION

The carbon monoxide stunning/slaughtering method could be applied to rainbow trout without detrimental effects on physical, chemical, or sensory characteristics of the fish flesh. © 2018 Society of Chemical Industry.

Rabbit meat production and consumption: State of knowledge and future perspectives

Since the 1970s, in some European countries rabbit meat production has progressively become a highly specialized industry, which has made Europe the second (after China) largest rabbit meat producer in the world. However, the industry is currently facing a critical period due to structural weaknesses, progressive and constant reductions in consumption, and raising criticism related to welfare conditions and other ethical issues. This trend is questioning the future of the rabbit meat industry, which could lead to the loss of knowledge and technical expertise acquired over decades of major investments and research efforts (a valuable cultural and professional heritage for future generations). In the present review, we provide an overview of the rabbit meat industry, market and value chain, we depict consumer's attitude towards rabbit meat, highlighting strengths and weaknesses, and factors driving their current purchase behavior. Finally, we will attempt to outline possible strategies to ensure a sustainable future for the production of rabbits for commercial meat purposes.

Effect of diet and packaging system on the oxidative status and polyunsaturated fatty acid content of rabbit meat during retail display

The aim of this study was to evaluate the combined effect of two dietary lipid sources (sunflower vs. linseed oil) and three packaging methods (PVC film - BAG vs. modified atmosphere CO₂ 20% + 80% O₂ - MAP vs. and vacuum - VAC) on the oxidative status and polyunsaturated fatty acid content of rabbit loins (Longissimus thoracis et lumborum muscle), at days 1, 4 and 10 of simulated retail display. The diet, storage time and packaging method affected the oxidative status of rabbit meat under retail display. As expected, storage time, independently on the other factors, significantly reduced the antioxidant content of loin meat. Accordingly, TBARs values significantly increased during storage, as well as the dietary supplementation of linseed. The fatty acid profile of the fresh loin closely respected that of the diets. At day 10, oxidative status and fatty acid profile of MAP samples could be yet considered optimal.

Carbon monoxide stunning of Atlantic salmon (Salmo salar L.) modifies rigor mortis and sensory traits as revealed by NIRS and other instruments

BACKGROUND

Methods of stunning used in salmon slaughter are still the subject of research. Fish quality can be influenced by pre-, ante- and post-mortem conditions, including handling before slaughter, slaughter methods and storage conditions. Carbon monoxide (CO) is known to improve colour stability in red muscle and to reduce microbial growth and lipid oxidation in live fish exposed to CO. Quality differences in Atlantic salmon, Salmo salar L., stunned by CO or percussion, were evaluated and compared by different techniques [near infrared reflectance spectroscopy (NIRS), electronic nose (EN), electronic tongue (ET)] and sensory analysis.

RESULTS

Thawed samples, freeze-dried preparates and NIRS devices proved to be the most efficient combinations for discriminating the treatments applied to salmon, i.e. first the stunning methods adopted, then the back-prediction of the maximum time to reach rigor mortis and finally to correlate some sensory attributes. A trained panel found significant differences between control and CO-stunned salmon: reduced tactile crumbliness, reduced odour and aroma intensities, and reduced tenderness of CO-treated fillets. CO stunning reduced radiation absorbance in spectra of thawed and freeze-dried fillets, but not fillet samples stored in ethanol, where it may have interacted with myoglobin and myosin.

CONCLUSIONS

The good results in a rapid discrimination of thawed samples detected by NIRS suggest suitable applications in the fish industry. CO treatment could mitigate sensory perception, but consumer tests are needed to confirm our findings. © 2015 Society of Chemical Industry.