KARAKTERISTIK BUAH DAN SAYUR UNIVERSITAS BRAWIJAYA 2013

Tujuan Matakuliah: Mahasiswa mengetahui dan memahami karakteristik BUAH DAN SAYUR serta mengetahui efek pengolahan terhadap karakteristiknya.

KARAKTERISTIK BUAH & SAYURAN

Tanaman Sebagai bhn pangan Akar Batang Daun Bunga Buah Biji Sayur dan Buah Sayur dan buah  secara anatomi tdk dpt dibedakan Dibedakan berdasarkan penggunaannya : - Sayur  biasa dimakan bersama makanan utama (nasi) -Buah  sebagai dessert ( dimakan segar )

BUAH = bagian tanaman hasil perkawinan putik dan benangsari mrpk tempat biji  mempunyai rasa manis asam, warna dan aroma yang khas SAYURAN = bagian tanaman (akar, daun, buah, biji, batang ) umumnya tanaman yang umurnya relatif pendek tdk berasa manis, warna dan tekstur yang beragam

KUALITAS SETELAH DIPANEN Tidak bisa dinaikkan Hanya bisa dipertahankan KUALITAS SETELAH DIPANEN Kualitas harus maksimal Penanganan baik  awet PADA SAAT DIPANEN INDIKATOR PANEN Kenampakan visual Indikator fisik Analisa kimia Indikator fisiologis

BUAH & SAYUR Kadar air tinggi > 70% - 85% Kadar protein : tidak lebih 3,5% Kadar lemak : tidak lebih 0,5% (kecuali alpokat) Sumber karbohidrat, 2 jenis : dapat dicerna (gula, pati) tidak dapat dicerna : dietary fiber (serat makanan) Sumber mineral dan vitamin Zat warna (pigmen)

BUAH

PENGGOLONGAN BUAH-BUAHAN MUSIM BERBUAH TIDAK musiman MUSIMAN IKLIM TEMPAT TUMBUH Buah tropis (iklim panas, suhu > 25°C) Buah sub tropis (iklim sedang, suhu maks 22°C) POLA RESPIRASI Buah KLIMAKTERIK Buah NON KLIMAKTERIK

Komposisi Buah Dipengaruhi beberapa faktor : Perbedaan varitas Keadaan iklim tempat tumbuh Pemeliharaan tanaman Cara pemanenan Tingkat kematangan waktu dipanen Kondisi selama pemeraman Kondisi penyimpanan

SAYUR Tanaman hortikultura Umur tanaman relatif pendek dibanding buah-buahan (< 1 th) Bukan tanaman musiman Setiap jenis/varitas : warna, rasa, aroma dan kekerasan berbeda Sumber mineral dan vitamin

PENGGOLONGAN SAYURAN BAGIAN DARI TANAMAN Akar Umbi Batang muda Tangkai daun Daun Bunga Buah Kecambah IKLIM TEMPAT TUMBUH Iklim panas (tropis). ≥25°C Iklim sedang (sub tropis) maks 22°C

TEKSTUR BUAH DAN SAYURAN Dipengaruhi turgor dari sel-sel yang masih hidup Turgor : tekanan dari isi sel terhadap dinding sel Dinding sel mempunyai sifat elastis Isi kandungan sel berkurang : sayuran lemas Isi kandungan sel bertambah melebihi kapasitas dinding sel, sel pecah, isi sel keluar, keteguhan sel hilang

FAKTOR-FAKTOR MEMPENGARUHI TURGOR Konsentrasi bahan-bahan di dalam sel yang akan menentukan tekanan osmosis Permeabilitas protoplasma Elastisitas dinding sel

Komposisi Buah dan Sayur Carbohydrates Represent more than 90 % of dry matter Sugar such as glucose, fructose, maltose and sucrose, all share the following characteristics : - supply energy for nutrition - readily fermented by …… - may used as a preservative - on heating they darken colour .. - combine with … to give dark colour as …

Starches - supply energy in nutrition - firming of plant tissues

Pectin and carbohydrates gums - in colloidal solution contribute to viscosity - in solution with sugar and acid are the basis of jelly

Cellulose and hemicellulose - act primarily as supporting structures - insoluble in cold and hot water - not digested, not yield energy

Mineral Substances 0,6 – 1,80 % ( K, Na, Ca, Mg, Fe, Mn, Al, P, Cl, S) salt of organic acid complex organic combination (chlorophyll, lecithin, etc) Ca and P essential for calcium fixation (Ca/P) : 0,7 for adults and 1,0 for children vegetable rich in P and Ca : green bean, cabbage and onion fruit rich in P and Ca : pears, lemon, oranges

Vitamins function as enzyme systems which facilitate the metabolism Divided into two major groups (fat soluble and wet soluble) Examples : Vitamin A/ Retinol found in the orange and yellow vegetables and green leafy vegetables Vit C / ascorbic acid and Vit E favours the absorption of iron and easily destroyed by oxidation at high temp.

Organic acids such as citric acid, malic acid, tartaric acid, etc these acids gives some function : 1. Fruit tartness and flavour 2. Slow down bacterial spoilage 3. Influence the colour of food

Pigment sources of colour classified into four major groups : Chlorophylls - oil soluble, bound to protein molecules - C alone is highly unstable (acid pH) - C changes becoming pheophytin (on heating), can be protected by addition alkali to the cooking or canning water

Carotenoids - fat soluble - fairly resistant to heat, change in pH and water leaching - very sensitive to oxidation

Flavonoids - water soluble 1. Anthocyanin shifting of color with pH violet/blue in alkaline or metal ions red in acid media 2. Anthoxanthin pH sensitives deeper yellow (in pH >8) and whiter yellow (in pH <6)

Enzymes Hidrolase (lipase, invertase, tannase, etc) biological catalyst promote biochamical reaction Hidrolase (lipase, invertase, tannase, etc) oxidoreductase (peroxide, catalase, etc) Some properties : control the reaction associated of ripening responsible for changing of flavor, color, texture and nutritional properties activity of enzyme is characterized by an optimal temp and pH

Major factors of fruit and vegetables deterioration Growth and activities of microorganism Activities of natural food enzymes Temperature, both heat and cold Moisture and dryness Air and in particular O2 Light

Methods of reducing deterioration The technical methods can be summarized as follow : Physical method Chemical method Biochemical method FOOD PROCESSING TECHNOLOGY

FRUIT AND VEGETABLE HANDLING GOALS STORAGE TRANSPORTATION MARKETING /DISTRIBUTION MAIN STEPS SORTING/GRADING WASHING PRE COOLING PACKING ADDITIONAL PROCESS CURING DE GREENING WAXING

Fresh fruit and vegetables - Possibilities of damage? - How to prevent?

Minimally processes Factors causing deterioration? How to prevent?

Fully processed food - Factors influencing the quality? - How to maintain the quality and retard the deterioration?