Zero discharge: Pilot project for biodegradation of cattle effluent by pyroclastic "lapilli" treatment for fodder irrigation.

Livestock effluents are a nutrient supply that is beneficial for crops, so their use is essential to guarantee the sustainability of the global management of farms. Zero discharge cattle effluent management to irrigate fodder crops is a mitigation option, so it is considered a key factor for adaptation to climate change. This paper presents the result of an "on site" pilot scale (three-stage, vertical flow filtration system using lapilli). This is a low-cost solution in terms of finance and energy, which does not require the addition of chemicals, to treat a cattle effluent. The effluent's quality obtained allowed it to be injected in a drip system with low risks of obstruction. And the pilot system allowed to obtain elimination values for the main parameters of effluent's quality (TSS and COD, 98% and 80% respectively) similar or greater than the ones obtained in other treatments of low cost and energy, and gives values contemplated in reclaimed water reuse guidelines of many countries. Furthermore, elimination rate for the BOD5 obtained 35 mgL-1 in treated effluent. High removal rates were obtained for N, P, K, Cu, Fe and Mn, medium for Ca, Mg and Zn and low for B and Na. These shows that the pilot system and fodder crop combination provide an optimal solution to small farms, controlling sanitary risks. The tested flow allows the use of this system by conventional small farms, which represented 94% of total cow farms in Canary Islands.

Lipolysis and proteolysis profiles of fresh artisanal goat cheese made with raw milk with 3 different fat contents.

The objective of this study was to describe the proteolysis and lipolysis profiles in goat cheese made in the Canary Islands (Spain) using raw milk with 3 different fat contents (0.5, 1.5, and 5%) and ripened for 1, 7, 14, and 28 d. ß-Casein was the most abundant protein in all cheeses and at all ripening times. Quantitative analysis showed a general decrease in caseins as ripening progressed, and degradation rates were higher for α(S1)-casein than for ß-casein and α(S2)-casein. Furthermore, the degradation rate during the experimental time decreased with lower fat contents. The α(S2)-casein and α(S1)-casein levels that remained in full-fat and reduced-fat cheeses were less than those in low-fat cheese. In contrast, ß-casein also showed degradation along with ripening, but differences in degradation among the 3 cheese types were not significant at 28 d. The degradation products increased with the ripening time in all cheeses, but they were higher in full-fat cheese than in reduced-fat and low-fat cheeses. The free fatty acid concentration per 100g of cheese was higher in full-fat cheese than in reduced- and low-fat cheese; however, when the results were expressed as milligrams of free fatty acids per gram of fat in cheese, then lipolysis occurred more rapidly in low-fat cheese than in reduced- and full-fat cheeses. These results may explain the atypical texture and off-flavors found in low-fat goat cheeses, likely the main causes of non-acceptance.