Public concern on the excessive use of synthetic food additives has raised a great interest to use natural products due to their potential in food and pharmacological industries. Nowadays, chemical food additives are questioned due to their contribution to the health risks and environmental impacts. Among natural additives, essential oils (EOs) are extracted from aromatic compounds and responsible for their biological activities namely antimicrobial and antioxidant capacity. Incorporation of bio-active compounds particularly EOs directly in food or edible/biodegradable food packaging seems to enhance the shelf life and quality characteristics of processed food and protect the consumers against oxidative and bacterial deterioration effects. However, inclusion of EOs in films/coatings for food packaging may put some effects on various properties (optic, tensile and etc.), which can affect the consumer acceptability. Their addition in food can cause some allergic and hypersensitivity reactions to the individuals who use them often. This paper aims to review the latest findings on the use of EOs incorporated with edible/biodegradable films and coatings to enhance the shelf life and quality of the food. Further investigations about essential oils are expected to clarify their exact action and build up their standard use in food industry.

Phytogenic feed additives have replaced the use of antibiotic growth promoters (AGP) in the diet of poultry particularly broiler chickens. Researchers are moving towards the use of natural products such as herbs, spices, plants and plant products, which possess influential effects on growth performance parameters, immune response and treatment of various diseases. Aloe vera is a well-known medicinal plant and is being used for commercial and therapeutic purposes such as antimicrobials, antitumor, anti-inflammatory, immunomodulator, wound healing, antioxidant and antiprotozoal agents. From a few last decades, the use of Aloe vera has been increased as a natural additive to broiler diet. Based on the review of literature, Aloe vera can improve immune response, growth performance in the broiler, as well as an excellent alternative of AGPs and anticoccidial drugs. It can be used for broiler diet in the form of gel, powder, ethanolic extract and aqueous extract. This review provides information about the use of Aloe vera in broiler production with reference to the effects on growth performance, immune system, intestinal microflora and coccidiosis in broiler chickens.

Recent studies designate feed additives, such as rumen-protected choline (RPC), were seen decreasing the health disorders and upsurges the milk yield. Choline is an endogenous agent and the insufficiency of choline is very problematic. The deficiency has been documented in ruminants for a while. The scale of choline production is affected by administered dose, lactation stage, and basal diet composition. Endogenous synthesis through a pathway (PEMT) signifies a precarious source of choline.  High occurrence of fatty liver disease happens in the dairy cows during lactation especially in the periparturient period and to lessen such incident high supply of choline is necessary. This supply is known to decrease the chances of hepatic fatty infiltration and upsurge the countenance of genes tangled in the transport of VLDL (very low-density lipoprotein). RPC typically provided as choline chloride is covered inside a shield of the fatty acid matrix. Therefore, to continue choline susceptibility on important mechanisms, like sparing of a methyl group (–CH3), supporting of animal metabolism, and remethylation of homocysteine via metabolite of betaine; choline must be provided in the rumen-protected form in the ration of dairy cows. Precisely concerning lactation, it is important to note that rumen-protected choline positively affects the performance of animals during the lactation period especially when supplementation started before calving and continues throughout the early lactation. But the difference of commercial products of rumen-protected choline in their rumen degradability and choline content is one of the big problems yet to be resolved.

Despite positive effects on nutrition, it has been reported that milk causes allergic reactions and many health problems. Allergic reaction to milk is called lactose intolerance, but it is estimated that this is not caused by lactose, but by the β -casein structure of milk, which varies depending on animal species. Although there are many fractions of β-casein in the structure of milk, especially A1 and A2 casein attract attention. A1 β -casein causes many health problems because it plays a role in the formation of the bioactive opioid peptide β-casomorphin-7 (β-CM-7). These health problems are allergic reactions, weakening of the immune system and slowing down of the gastro-intestinal system and some systemic diseases (cardiovascular disease, type 1 diabetes, autism, schizophrenia). The underdevelopment of gastro-intestinal system, especially in newborns, causes us to encounter these health problems more frequently. For this reason, the consumption of milk containing A1 β-casein, especially cow’s milk from culture breeds, is not recommended. Since BKM-7 (β-casomorphin-7) formed by A1 β-casein cannot occur in A2 β-casein, these health problems cannot be expected to be observed. However, A2 β-casein causes DPP4 (dipeptidyl peptidase 4) enzymes to be regulated in the body and a non-opioid effect is observed. It is recommended to consume goat’s milk and dairy products containing A2 β-casein in newborns, people with celiac disease and stomach disorders. Despite the lack of studies on the subject of A1 and A2 β-casein and the ongoing discussions, in this review, the importance and differences of A1 and A2 β-caseins in cow and goat milk were discussed and their effects on human health.