Efeito de diferentes plastificantes na vida de prateleira de ovos revestidos com proteína concentrada do leite

O ovo é um alimento completo e funcional, consumido diariamente no mundo inteiro. Algumas tecnologias podem ser utilizadas para manter a qualidade deste produto e garantir sua inocuidade. Os revestimentos são uma dessas tecnologias, que podem prolongar a vida de prateleira do produto. Inúmeras substâncias já foram testadas como alternativas de revestimento, dentre elas está a proteína concentrada do leite. Os plastificantes também podem ser utilizados na confecção dos revestimentos para conferir mobilidade. Dentre a gama de plastificantes disponíveis, o glicerol, sorbitol e propilenoglicol são os mais utilizados para revestimentos a base de proteína. Contudo, o efeito destes plastificantes na qualidade dos ovos durante o armazenamento ainda é pouco conhecido. O objetivo deste trabalho foi avaliar o efeito de revestimentos a base de proteína concentrada do leite (PCL) e de diferentes plastificantes na qualidade de ovos comerciais durante o armazenamento. Foram utilizados 336 ovos produzidos por aves da linhagem ISA Brown de idades semelhantes. Os ovos foram aleatoriamente distribuídos em quatro tratamentos: controle, ovos sem revestimento; ovos revestidos com solução de PCL contendo glicerol; ovos revestidos com solução de PCL contendo sorbitol e ovos revestidos com solução de PCL contendo propilenoglicol. Os ovos foram condicionados em sala com controle de umidade por 42 dias. Perda de peso, Unidade Haugh, índice de gema, pH do albúmen e gema foram avaliados no dia zero e semanalmente durante o período de armazenamento. Os dados foram submetidos a análise de variância utilizando o software Minitab 18 e as eventuais diferenças entre as médias foram avaliadas através do teste de Tukey a 5% de probabilidade. Após 42 dias de armazenamento, os ovos que receberam revestimento apresentaram maiores (p<0,05) escores de Unidade Haugh e menor (p<0,05) perda de peso e pH do albumen quando comparados ao tratamento controle. O plastificante sorbitol foi o que apresentou a menor perda de peso (p<0,05) dentre os tratamentos com revestimento. No final do experimento, ovos revestidos com PCL + propilenoglicol apresentaram maior (p<0,05) Unidade Haugh (71,53) em comparação com sorbitol (68,70) e glicerol (66,58). Tais resultados indicam uma qualidade superior dos ovos com revestimento em relação aos não revestidos, mesmo após 42 dias de armazenamento. O sorbitol e o propilenoglicol são alternativas viáveis ao uso do glicerol para confecção de revestimentos.The egg is a complete and functional food, consumed daily worldwide. Some technologies can be used to maintain the quality of this product and ensure its safety. Coatings are the technologies that can extend the life of the product. Numerous substances have been tested as coating alternatives, and whey protein it is one of them. Plasticizers can also be used in the edible films to confer for mobility. There are many available plasticizer, glycerol, sorbitol and propylene glycol are most commonly used for films based on protein. The purpose of this study was to evaluate the effect of concentrated whey protein edible films (CWP) and different plasticizers in the quality of the commercial eggs during storage. There were used 336 eggs produced by Isa Brown laying hens of similar ages. The eggs were randomly distributed in four treatments: control, uncoated eggs; Eggs coated with glycerol-containing CWP solution; eggs coated with CWP solution containing sorbitol and eggs coated with CWP solution containing propylene glycol. The eggs were stored in a room with temperature control for 42 days. Weight loss, Haugh Unit, yolk index, albumen and yolk pH were evaluated at day zero and during the storage period. The data were submitted to an analysis of variance using the software Minitab 18 and the following differences between the averages were evaluated through the Tukey test at 5% probability. After 42 days of storage, the coating treatments had higher (p<0.05) Haugh Unit and yolk index and lower (p<0.05) weight loss and albumen pH when compared to the control eggs. The plasticizer sorbitol presented the lower weight loss (p<0.05) between the coating treatments. At the end of the experiment, eggs coated with CWP + propylene glycol had higher (p<0.05) Haugh Unit (71.53) compared to sorbitol (68.70) and glycerol (66.58). These results indicated a greater quality in the coated eggs when compared to uncoated eggs, even after 42 days of storage. Sorbitol and propylene glycol are viable alternatives to the use of glycerol for coating

Comparação de métodos de determinação de umidade: secagem em estufa e liofilização.

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Effects of rice protein coating enriched with essential oils on internal quality and shelf life of eggs during room temperature storage

The effectiveness of rice protein coatings enriched with essential oils on maintaining interior quality of fresh eggs was evaluated during storage at 20°C for 6 wk. Egg quality was assessed by weight loss, Haugh unit (HU), albumen pH, and yolk index (YI) in uncoated eggs (control treatment) and eggs coated with rice protein concentrate at 8% enriched or not with different essential oils (1%): tea tree (Melaleuca alternifolia), copaíba (Copaifera langsdorffii), or thymo (Thymus vulgaris). The HU and YI were higher in coated eggs (P < 0.001). Data were submitted to variance analysis, and the statistical models included the effects of treatments (coating types), storage periods (weeks), and interaction (treatments by storage periods). Weight loss increased (P < 0.001) during long-term storage. Uncoated eggs showed the highest weight loss (5.43%), whereas coatings of rice protein alone (4.23%) or enriched with tea tree (4.10%), copaiba (3.90%), and thymo (4.08%) solutions were effective in preventing weight lost (P < 0.001). The coating use preserved the internal quality of the eggs for up to 3 wk longer than uncoated eggs in terms of HU, YI, and pH. Uncoated eggs had the worst (P < 0.001) HU (58.46), albumen pH (9.48), and YI (0.33) after 6 wk of storage. In conclusion, the use of coatings based on rice protein concentrate enriched with different essential oils influences the internal quality of eggs during storage and may be an effective alternative for increasing the shelf life of commercial eggs

Changes in the ceca microbiota of broilers vaccinated for coccidiosis or supplemented with salinomycin

The objective of this study was to characterize differences in the cecal microbiota of chickens vaccinated for coccidiosis or receiving salinomycin in the diet. In this study, 140 male 1-day-old broiler chickens were divided in 2 groups: vaccine group (live vaccine) vaccinated at the first day and salinomycin group (125 ppm/kg since the first day until 35 d of age). Each treatment was composed for 7 replicates of 10 birds per pen. At 28 d, the cecal content of one bird per replicate was collected for microbiota analysis. The genetic sequencing was conducted by the Miseq Illumina platform. Vaccine group showed lower body weight, weight gain, and poorer feed conversion in the total period (P 0.05). The richness distribution in the salinomycin group was larger and more uniform than the vaccinated birds. Salinomycin group was related to the enrichment of Bacteroidetes, whereas Firmicutes and Proteobacteria phyla were in greater proportions in the vaccine group. The last phylum includes a wide variety of pathogenic bacteria. The vaccine did not decrease the species richness but decreased the percentage of Bacteroidetes, a phylum composed by genera that produce short-chain fatty acids improving intestinal health. Vaccine group also had higher Proteobacteria phylum, which may help explain its poorer performance

Using probiotics to improve nutrient digestibility and gut-health of weaned pigs: a comparison of maternal and nursery supplementation strategies

Maternal probiotic supplementation has been found to have a positive impact on the gut health of piglets, not only during the lactation period, but also after weaning. Providing probiotics to nursery pigs is also a common strategy for supplementation. The goal of this study was to evaluate which would be the most effective strategy to improve nutrient digestibility, energy metabolism, and intestinal health in weaned pigs considering the maternal or nursery options. A total of 32 newly weaned pigs were randomly split into a 2 × 2 factorial arrangement considering maternal probiotic supplementation (with or without) in gestation-lactation and probiotic supplementation in the nursery period (with or without). After weaning, experimental diets were provided for 22 days. Total fecal and urine collection was performed from day 15 to 21. Blood samples were collected from all pigs on days 3 and 22 of the experiment to assess serum biochemistry and intestinal permeability. All pigs were euthanized on day 22 for intestinal tissue collection. Pigs born from probiotic-fed sows had greater (p &lt; 0.05) total tract digestibility of dry matter (+1%) and gross energy (+1.3%), and greater (p &lt; 0.05) metabolizable energy coefficient (+1.3%), which resulted in a 46 kcal/kg increase (p &lt; 0.05) in the metabolizable energy content of the diet. Nitrogen intake (p = 0.035), uptake (p = 0.007), and retention (p = 0.012) were all increased in these pigs. Fecal moisture was reduced in pigs born from probiotic-fed sows and pigs fed the probiotic diet only in the nursery (p &lt; 0.05). Pigs born from probiotic-fed sows had reduced intestinal permeability by 16% (p &lt; 0.05), whereas pigs fed the probiotic diet in the nursery only tended to improve this response (p &lt; 0.10). The villus:crypt ratio of pigs born from probiotic-fed sows was greater compared to the control (p &lt; 0.05), while serum levels of alanine aminotransferase were lower (p &lt; 0.05). Pigs born from probiotic-fed sows had increased nutrient digestibility and improved gut health. Therefore, it is concluded that supplementing the sow diets with probiotics rather than just providing diets in the nursery phase is an advantageous strategy