The aim of this study was to evaluate the changes in the content of bioactive, nutritional and anti-nutritional factors in rapeseed meal that was fermented with Saccharomyces cerevisiae or Saccharomyces boulardii yeasts at two different periods of time, for improvement of nutritional characteristics in piglets’ feeding. The fermentation has reduced the content of two anti-nutritional factors, intact glucosinolates and 3-butyl isothiocyanate, by 51.60–66.04% and 55.21–63.39%, respectively, by fermentation with either Saccharomyces cerevisiae or Saccharomyces boulardii for 24 h. The fermentation by these yeasts also lowered the content of total polyphenolic compounds by 21.58–23.55% and antioxidant activity (DPPH) by 17.03–21.07%. Furthermore, the content of carbohydrates and organic acids has dramatically decreased between 89.20 and 98.35% and between 31.48 and 77.18%, respectively. However, the content of some individual phenolic acids (gallic, p-coumaric, sinapic) and crude protein content (10–13%) has been increased. Thus, the results showed that fermentation with Saccharomyces cerevisiae or Saccharomyces boulardii has reduced the content of antinutritive factors and increased the protein content of the rapeseed meal, without major adverse effects on its overall nutritive value.

The aim of this work was to evaluate the influence of a diet containing 5% dried GP on the antioxidant status (total antioxidant status (TAS), antioxidant enzyme activity (catalase-CAT, superoxide dismutase-SOD, and gluthatione peroxidase-GPx), and lipid peroxidation) on the key organs of the liver, kidneys, and spleen in relation to health status as indicated by blood biochemical parameters and total polyphenol content in the blood, organs (liver, spleen, kidney, mesenteric lymph nodes, heart, and brain) and Longissimus dorsi muscle in piglets. The GP diet results in a significant increase of TAS in the liver, spleen, and kidneys, with increased CAT activity in the spleen and kidneys, increased SOD activity in the liver, kidneys, and spleen, and increased GPx activity in the kidneys, as well as a decrease in lipid peroxidation in the liver and kidneys. The GP included in the piglets’ feed contained polyphenols that showed antioxidant activity and were absorbed in the plasma, contributing to maintaining the good health of the animals. The inclusion of 5% GP inclusion in the diets of piglets is beneficial for overall normal blood constituent metabolism and helps to maintain piglet health by increasing the polyphenol content in blood plasma and antioxidant activity in the liver, spleen, and kidneys.

Having a complex fatty acid profile, milk is the subject of several oxidation processes that are different to those in other food matrices. Considering this, is important to appreciate the degradation status of milk using rapid and simple methods to quantify the main degradation products. The aim of this study was to adapt a simple and rapid method for determination of milk oxidative stability and to quantify malondialdehyde, one of the lipid oxidation products. Four parameters (trichloroacetic acid concentration—TCA, antioxidant type, incubation time, and thiobarbituric acid—TBA concentration) were modified to establish the best experimental sequence. It was concluded that the relevant results were obtained by precipitating milk proteins using 20% TCA; incubating samples for 90 min with 0.8% TBA, without adding antioxidant; and registering absorbance at three different wavelengths (450, 495, and 532 nm). This method was successfully applied to cow and sheep milk samples and the absorbance values obtained provided information about degradation of fatty acids for both milk types. The Pearson correlation showed a positive relationship between the fatty acid profiles of milk samples and the absorbance values that characterized their oxidation pattern during storage.

Agricultural waste from the fruit and vegetable industry is used as an alternative source of animal feed, but detailed investigations are required. The aim of this work was to conduct a physico-chemical characterization, through analytical techniques, of fruit and vegetable wastes such as those of golden apples, red apples, carrots, celery, beetroots, and red potato peels. The bioactive compounds in the samples indicated a high carbohydrate content of 50.38 g/100 g in golden apples and 59.38 mg/100 g of organic acids in celery. In addition, the total phenolic content (TPC, mg gallic acid equivalent/g dry weight) varied between 3.72 in celery and 15.51 in beetroots. The antioxidant capacity values were significant. A thermal analysis showed thermal stability and weight loss, underscoring the composition of the solid samples. An infrared spectroscopy (FTIR) analysis showed C-H, O-H, C=O, and N-H functional groups in non-starchy carbohydrates, organic acids, and proteins. Microscopic techniques revealed the microstructure, particle size, and semicrystalline profile of the samples. The ultrastructure (determined via atomic force microscopy (AFM)) of celery consisted of a smooth and uniform surface with a lignin and cellulose texture. These results highlight the importance of fruit and vegetable waste as an alternative source of essential nutrients and bioactive compounds for animal feed.

Brewer’s spent yeast (BSY) is a byproduct of the beer industry, rich in proteins and bioactive compounds. The effects of BSY were investigated through a 6-week feeding trial on 30 lactating dairy Blackhead sheep (54.7 ± 5.66 kg, 177.34 days in milk) distributed under a completely randomised design in two groups: a control group (with soybean meal and sunflower meal as protein sources), and a BSY group, where soybean meal was totally replaced by BSY (5.4% inclusion, DM basis). The inclusion of BSY led to a 25% decrease in ruminal propionate and in the acetate/propionate ratio. BSY influenced the milk fatty acid profile by significantly decreasing the omega 6: omega 3 ratio and increasing the contents of caproic, capric, and lauric acids. Also, the inclusion of BSY was associated with an increase in the milk’s total polyphenols. Consistently, determinations of the parameters of the milk fat’s oxidative stability revealed a decrease in conjugated diene contents. Moreover, the mineral contents of milk were influenced, with an increase in Ca content noted. Overall, these results indicate that BSY represents an alternative feedstuff for ruminants’ nutrition, which could have the potential to induce changes in ruminal fermentation and milk composition that are beneficial for consumers.

The food industry is intensifying its effort to enrich food composition in various nutrients through animal feeding, but these challenges can be limited by the costly feed resources, water scarcity, and pesticide pollution, making it crucial to explore alternative feedstuffs with fewer requirements. Blackthorns and hawthorns are characterized by their rich phytochemical and antioxidant profiles, suggesting their potential to enhance the performance of ruminants though the supply of bioactive substances. Our study revealed their rich composition of micronutrients; hawthorns showed a remarkable amount of polyunsaturated fatty acids (57.23 g FAME/100 g total FAME), particularly omega-3 and omega-6, while blackthorn presented higher concentration of monounsaturated fatty acids, specifically oleic acid (56.99 g FAME/100 g total FAME). In terms of lipo-soluble antioxidants, blackthorn exhibited higher levels of xanthophyll and vitamin E (123.83 mg/kg DM), including its isomers (alpha, gamma, and delta). Concerning the water-soluble antioxidants, hawthorns showed elevated composition of the total content of flavonoids and polyphenols, comparing with blackthorn. Moreover, hawthorns showed a high antioxidant capacity, as assessed through DPPH, ABTS, and TAC analyses. In terms of the scavenging capacity of blackthorn and hawthorn against superoxide radicals, blackthorn had higher radical scavenging potential against superoxide radicals, compared to hawthorn.