ALTERNATIVE INGREDIENTS
Insects in aquaculture feed: Nutrition and beyond Bree Modica, EnviroFlight®
Insects, although natural food items for many animals, have only recently entered the commercial agriculture industry. The most common insects used in animal feeds and pet foods are crickets (Gryllidae), mealworms (Tenebrio molitor), and larvae of the black soldier fly (BSFL; Hermetia illucens). Commercially produced insect ingredients are available as whole dried insect, meal (partially defatted or full fat), oil, and frass (residue from rearing insects including leftover feed, feces, and sheddings). Insects are known for their high protein content and comparable amino acid profiles to those of traditional protein sources, including menhaden fishmeal and soybean meal (Table 1). However, they are also excellent sources of fats, vitamins and minerals. Nutrient composition of insects will vary depending on diet and life stage at harvest, increasing possibilities for
custom insect ingredient nutrient profiles, specifically regarding protein, omega-3 fatty acids, and calcium (Gligorescu et al., 2018; Oonincx et al., 2019). In addition to nutrient content, insects are also highly sustainable (Fig. 1). In comparison to the annual protein yield of soybean crops at 0.12 kg/m2, average insect protein yields (accounting for feedstock inputs) have been reported at 2.18, 4.06, and up to 7.93 kg/ m2 for crickets, mealworms, and black soldier fly larvae, respectively (Koutsos et al., 2019). Greater insect protein yields are due to the increased number of annual growth cycles that are yet unattainable with crops (Koutsos et al., 2019). These yields also require significantly less water, feed, and land while producing much less CO2. Phan Van PhI et al. (2020) demonstrated a 51% reduction in CO2 emissions
Table 1. Essential amino acids and associated digestibility (in parentheses) for three novel insect (BSFL, cricket, mealworm) and two traditional (soybean, menhaden fish) meals.
Nutrient (%) BSFL meal1 Cricket meal1 Mealworm meal1 Crude Protein
1
Soybean meal2
Menhaden fishmeal2
54.4
67.4
53.4
45.3
61.3
Arg
2.64 (92)
4.17 (88)
2.93 (94)
3.36 (94)
3.68 (92)
His
1.72 (87)
1.77 (78)
1.75 (91)
1.20 (91)
1.42 (89)
Ile
2.50 (90)
3.31 (83)
2.60 (91)
2.09 (90)
2.28 (92)
Leu
3.77 (90)
5.39 (84)
4.09 (92)
3.34 (89)
4.16 (92)
Lys
4.00 (87)
4.32 (81)
3.41 (89)
2.78 (90)
4.51 (88)
Met
0.90 (93)
1.13 (88)
0.76 (91)
0.64 (92)
1.63 (92)
Phe
2.36 (91)
2.54 (86)
2.26 (91)
2.28 (91)
2.21 (91)
Thr
2.18 (88)
2.63 (84)
2.24 (91)
1.77 (91)
2.46 (89)
Trp
0.79 (97)
0.70 (93)
0.62 (99)
0.59
0.49
Val
5.10 (74)
6.31 (70)
5.69 (74)
2.18 (88)
2.77 (91)
Cys
0.62 (72)
0.73 (69)
0.64 (76)
0.67 (86)
0.57 (73)
Tyr
3.34 (91)
3.69 (77)
4.00 (94)
1.25
1.80
Matin, 2019 2NRC, 1994
Aquafeed: Advances in Processing & Formulation Vol 14 Issue 1 2022
