What and what not to eat and Where:
1) Not even water to be taken in the morning until the completion of Puja to Ayyappa,.
2) Eat any breaskfast in the morning made by yourself or any other Ayyappa or Matha, In case this is not feasible, elders above 50 years of age can cook for you, after they have had headbath.
3) Spices, foods with good amount of Chillies or Salts which may hamper maintaining moods or feelings. which should not override the saintly behavior one should have during the time of Deeksha. Harsh foods tend to have great impact on ones moods and normal food which is closer to nature (involving more of Fruits, Vegetables etc) helps in keeping anger and other feelings under control.
4) Tubers Grown under the soil should be avoided, Onions, Carrots, Garlic, Ginger, Grountnuts. etc.,
5) In case home made foods are not available or feasible devotees can rely on the other stalls that Ayyappa's maintain, But again at your discretion.
6) Do not eat or Drink in any other place.
7) Some temples offer Annadanam for Ayyappa's during Karthika Masam. One can avail such opportunity to have Lunch and Dinner there.